ASSAM POWER DISTRIBUTION COMPANY LIMITED
BID DOCUMENT
FOR
Strengthening & Upgradation of Sub-transmission
and Distribution works of project areas
Nagaon, Morigaon, Dhing, Doboka,
Jagiroad, Hojai & Lanka
UNDER
NAGAON ELECTRICAL CIRCLE,
APDCL (CAZ)
ON
“TURNKEY” MODE
VOLUME - II
SCHEME: R-APDRP (Part-B)
PACKAGE - II
NIT No: APDCL /CGM (PP&D) /R-APDRP/Part-B/NGN EC
MAY’2012
Technical Specification
PART-Y
STANDARD TECHNICAL SPECIFICATION
SECTION -I
GENERAL REQUIREMENTS
The bidder shall comply with the following general requirements along with other
specifications.
1.0
QUALITY ASSURANCE PLAN
1.1
The bidder shall invariably furnish the following information along with his offer
failing which the offer shall be liable for rejection. Information shall be separately
given for individual type of equipment offered.
i)
The structure of organization
ii)
The duties and responsibilities assigned to staff ensuring quality of work
iii)
The system of purchasing, taking delivery and verification of materials
iv)
The system for ensuring quality of workmanship
v)
The quality assurance arrangements shall confirm
requirement of ISO 9001 on ISO 9002 as applicable.
vi)
Statement giving list of important raw materials, names of sub-supplies for the
raw materials, list of standards according to which the raw material are tested,
list of tests normally carried out on raw material in the presence of suppliers
representative, copies of test certificates.
to
the
relevant
vii) Information and copies of test certificates as on (i) above in respect of
bought out items
viii) List of manufacturing facilities available
ix)
Level of automation achieved and list of areas where manual processing
exists.
x)
List of areas in manufacturing process, where stage inspections are
normally carried out for quality control and details of such test and
inspection.
xi)
List of testing equipment available with the bidder for final testing of
equipment specified and test plant limitation, if any vis-a-vis the type.
Special acceptance and routine tests specified in the relevant standards.
These limitations shall be very clearly brought out in "Schedule of
Deviations" from the specified test requirement.
1.2 The contactor shall within 30 days of placement of order, submit the following
information to the purchaser.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
i) List of the raw material as well as bought out accessories and the names of subsuppliers selected from those furnished along with the offer.
ii) Type test certificates of the raw material and bought out accessories if
required by the purchaser.
iii) Quality Assurance Plant (QAP) with hold points for purchasers inspection.
QAP and purchasers hold points shall be discussed between the purchaser and
contractor before the QAP is finalized.
The contractor shall submit the routine test certificates of bought out accessories
and central excise asses for raw material at the time of routine testing if required by
the purchaser and ensure that the quality assurance requirements of specification
are followed by the sub-contractor.
1.3
The Quality Assurance Programme shall give a description of the Quality System
and Quality Plans with the following details.
i) Quality System
 The structure of the organization.
 The duties and responsibilities assigned to staff ensuring quality of
work.
 The system of purchasing, taking delivery of verification of materials.
 The system of ensuring of quality workmanship.
 The system of control of documentation .
 The system of retention of records.
 The arrangement of contractor internal auditing.
 A list of administrator and work procedures required to achieve
contractors quality requirements. These procedures shall be made
readily available to the purchaser for inspection on request.
ii)
Quality Plans
 An outline of the proposed work and program sequence.
 The structure of contractor's organizations for the contract.
 The duties and responsibilities ensuring quality of work.
 Hold and notification points.
 Submission of engineering documents required by this pecification.
 The inspection of the materials and components on request.
 Reference to contractors work procedures appropriate to each activity.
 Inspection during fabrication/construction
 Final inspection and test.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
SECTION-2
TECHNICAL SPECIFICATIONS FOR 33/11kV POWER TRANSFORMER
1.0 SCOPE OF SPECIFICATION:
1.1. : This specification is intended to cover design, manufacture, assembly testing
at manufacturer‟s works, supply and delivery of three phase 50HZ, 33/11 KV
Delta/Star, Vector Group DY 11, two windings copper would outdoor type, oil
immersed, naturally air cooled Power Transformer with off load tap changer for
10MVA , 5 and 2.5MVA transformer.
1.2. The transformer offered shall be complete with all parts and accessories which
are necessary for their efficient and satisfactory operation The Transformer and
all associated oil filled Equipment shall be supplied complete with insulating
new oil required for first filling including 10% extra oil for future use during
commissioning. The Transformer tank shall be dispatched completely filled with
oil and the balance oil shall be supplied in non returnable sealed drums along
with the Transformers.
1.3. Such parts and accessories shall be deemed to be within the scope of this
specification whether specifically mentioned or not. Main tank body may be
delivered in unpacked condition, but delicate parts like indicating meter,
radiator, conservator, Pressure Relief Valve, equalizer pipe, buchholz relay etc.
shall be packed to avoid damage due to transportation.
1.4. It may be noted that the Power Transformer must meet the following minimum
criteria. Failure to comply with the requirements may results in rejection of the
BID as non-responsive:
1.5. The Manufacturer must have designed, manufactured, type tested and supplied
power transformers in at least two power utilities of similar rating which are in
successful operation for at least 5 (Five) years as on the date of bid opening.
Which should be substantiated by furnishing performance report by the official
of the rank of minimum DGM/SE
1.6. The Manufacturer should have in-house Auto Clave facility
1.7. Impulse Test, Temperature Rise and Loss Measurement shall be carried out at
CPRI / NABL accredited Laboratory.
.
2.0 : ISOCERAUNIC CONDITION:
2.1. For the purpose of designing, the following condition shall be considered:
1. Maximum temperature of air in shade
40°C
2. Minimum temperature of air in shade
2°C
3. Maximum temperature of air in sun
45°C
4. Maximum humidity
100%
5. Average number of thunder storm days
45 Days
per
annum
6. Maximum rainfall per annum
3500 mm
7. Average rainfall per annum
2200 mm
8. Wind pressure
97.8 Kg/m2
9. Altitude above MSL
100
to 1000 M
3.0 APPLICABLE STANDARDS
3.1. Unless otherwise stated, transformer shall be designed, constructed and tested
in accordance with provisions contained in latest revisions of following Indian
standards and Rules.
i) IS : 2026
ii) R.E.C. Manual 10/1976
iii) C.B. I.P. Manual on Transformer
Technical Report 1: Section : A.D. (Revised: 1987)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
iv) C.B.I.P. Technical Report No. 72 (June: 1989)
v) Indian Electricity Rules, 1956 (Amended up to date)
vi) IS : 2099 Bushing for alternating voltage above 1000 volt
vii) IS : 6600 Guide for loading of oil immersed transformer
viii) Specification for Transformer oil (IS-335 & IS-1866,1983)
ix) Other applicable Indian Standards.
4.0 GUARANTEES
4.1. The
bidder shall guarantee among other things the following:
a) Quality and strength of the material used.
b) Adequate factors of safety for all parts of equipment to withstand the
mechanical and on electrical stresses developed therein. These will be
stated in the tender.
c) Suitability of the design and workmanship of the equipment for the
conditions envisaged in the specification.
d) Efficiencies, Temperature rise and other performance data on
equipment which shall be furnished in the tender.
5.0 WARRANTEES
5.1. The bidder shall be responsible for replacing at site free of cost any part or parts
of the equipment that may prove faulty or fail manufacturing defects on one or
more of the reasons given in clause Error! Reference source not found. stated
above within 5 (five) years commencing from the date of commissioning
5.2. In case of failure of the transformer, the supplier shall take back the faulty
transformer from its plinth for repair at their own cost (or replace the
transformer with a new transformer) and deliver, at their own cost, unload at the
destination sub-station transformer plinth within 45 days, from the date of
intimation of defects to the satisfaction of the owner, at free of cost. If the
repair/replacement will not be completed within 45 days, then the supplier shall
pay penalty @ 0.5% of the contract price for each calendar week of delay from
the end of 45 days from the date of intimation of defects. Also, the Purchaser
reserves the right for forfeiture of the total Composite Bank Guarantee and all
the Securities, available with ASEB, in case the Supplier fails to pay the penalty
by one month before the expiry of the guarantee period. Also, this will be taken
as adverse in all future tenders.
5.3. The bidder shall furnish copies of test certificates of materials used for
manufacture and also the test certificates of the tests conducted on the
equipment after manufacture. The contractor shall also furnish the test
certificate of bought out components for approval by the purchaser.
6.0 MISCELLANEOUS
6.1. Padlocks along with duplicate keys as asked for various valves, marshalling box
etc. shall be supplied by the contractor, wherever applicable.
6.2. Foundation bolt for wheel locking devices of Transformer shall be supplied by
the bidder.
7.0 DELIVERY SCHEDULE:
7.1. The equipment shall be delivered FOR Destination as per schedule specified in
the BPS
8.0 CONFLICT IN CLAUSE:
8.1. In case of any conflict between the Specific Technical Requirements and
General Technical Requirements the requirements
indicated as Specific
Technical Requirement shall prevail over the General Technical Requirements
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
9.0 DEVIATION FROM SPECIFICATION
9.1. Normally the offer should be as per Technical Specification without any
deviation. But any deviation felt necessary to improve utility, performance and
efficiency of equipment or to secure overall economy shall be mentioned in the
„Schedule of deviations” with full justification, supported by documentary
evidence. Such deviations, suggested, may or may not be accepted. But
deviations, not mentioned in the “Deviation Schedule” will not be considered.
10.0 DRAWINGS INCORPORATING THE FOLLOWING PARTICULARS SHALL BE
SUBMITTED WITH THE BID:
10.1. The following drawings and details shall be furnished in triplicate along with the
bid :
10.2. General Arrangement outline drawing with plan, elevation and end views
showing various dimensions of transformer and its vital component including
height of the bottom most portion of bushing from the bottom of base channel
and also indicating thereon physical centre line and position of centre of gravity.
10.3. Details of various types of bushing.
10.4. Three copies of sketches for height of crane hook above ground for lifting and
untanking core, shipping dimensions, complete lists of fittings and devices, net
weights of core, winding, tank, radiator, oil, conservator and total weight, fixing
arrangement of transformer in foundation.
10.5. Illustrative & descriptive literature of the Transformer.
10.6. Maintenance and operation Instructions.
10.7. Type test certificates of similar transformers.
11.0
RATING AND GENERAL PARTICULARS:
Type: Core type, three phase, oil immersed, step down, two winding copper
wound transformer for outdoor installation.
11.2. Standard Rating:
11.1.
Continuous with off circuit taps as mentioned in the schedule of requirement.
11.3.
Continuous Maximum Rating and Overloads:
As regards maximum rating and temperature rise, all transformers shall comply with
the appropriate requirement of Indian Standards For the purpose of consideration
of maximum temperature rise of oil and winding, the following ambient
temperatures are assumed.
i) Cooling medium : Air
ii) Maximum Ambient Air temperature: 50 °C.
iii) Maximum daily average ambient Air temperature: 40 °C.
iv) Maximum yearly weighted average temperature: 32 °C .
The transformer may be operated without danger on any particular tapping at
the rated KVA provided the voltage does not vary by more than +10% of the voltage at
that tapping.
11.5.
The transformer should be suitable for continuous operation with a frequency
variation of +3% from normal 50Hz. Combined voltage and frequency variation should not
exceed the rated V/f ratio by 10%
11.4.
DUTY UNDER FAUALT CONDITION
It is to be assumed that normal voltage will be maintained on one side of the
Transformer when there is a short circuit between phases or to earth on the other side.
11.8.
The transformer may be directly connected to an underground or overhead
line and may be switched into and out of service together with or without its associated
incoming/outgoing line.
11.9.
The thermal ability to withstand short circuit shall be Two seconds (2 Sec.)
without injury for 3 phase dead short circuit at the terminals.
11.6.
11.7.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
12.0
GENERAL TECHNICAL PARAMETERS
SN
9.
10.
11.
12.
13.
Particulars
Rating
Number of Phases
Vector group
Type of installation
Frequency
Cooling Medium
Type of Cooling
Highest continuous system
Voltage
High Voltage
Low Voltage
Winding Connection
Material
High Voltage Winding
Low Voltage Winding
Method of System Earthing
14.
Type of Tap Changer
15.
Range of Tapping
16.
18.
19.
Type
of
Insulation
Insulation Level
a) Type of insulation
b) One
minute
power
frequency
withstand
Voltage(kV rms)
c) Lightning
Impulse
withstand voltage
Terminal Details
33kV Termination
20.
11 KV Termination
1.
2.
3.
4.
5.
6.
7.
8.
17.
10MVA
5MVA
Three
Dyn-11
Outdoor
50HZ ( +/- )3%
Insulating Oil
ONAN
2.5 MVA
:36kV
:12kV
Electrolytic Copper
DELTA
STAR
Solidly grounded on LV side
10 MVA 5 MVA
2.5 MVA
OFF
OFF
OFF Load
Load
Load
(+) 3% to (-) 9% in steps of 3%
on HV side
and 33kV
11kV
Uniform
70kV
Uniform
28kV
170
75
(i) ACSR/AAAC Wolf conductor, Bus,
(or IPs tube as
applicable) for
connecting to bushing terminals.
Cable 300/630 mm2, 1-core Al.
Armoured XLPE Cable
21. Maximum Temperature rise over
ambient of 50° C
a) Temperature rise of top oil 40° C (measured by Thermometer
b) Temperature rise of 45° C
winding
resistance)
C)
Maximum
Winding 105° C
temperature in Deg. C
d)
Maximum Permissible 250° C
value
of
Average
temperature of winding after
3 sec Maximum Permissible
short circuit:
(measured
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
12.1.
Over load capacity
12.2.
NOISE LEVEL AT RATED VOLTAGE & FREQUENCY: As per NEMA Pub TR-1.
13.0
:
As per IS: 6600
GUARANTEED LOSSES
1.
2.
3.
Impedance at rated MVA at 8.35%
75° C without (-) ve tolerance
No Load Loss
6.0KW
Load Loss at 75° C
44.0KW
7.15%
6.25%
4.0KW
24KW
2.1KW
14.0.0KW
13.1.
Tolerance of losses shall be guided by the relevant clauses of relevant IS standard.
The bidder shall state both no load loss and load loss at rated voltage and frequency and loss
figures shall be firm and guaranteed.
14.0
Evaluation of Losses:
For the purpose of comparison of bids, the capitalized cost of iron loss (KW)
and load losses (KW) shall be added to the quoted price of transformer at the following
rates.
14.1.
Iron loss per KW – Rs. 287 834.00
Copper loss per KW – Rs. 86349.00
14.2. If any or all actual losses after test are found to exceed the guaranteed value,
the penalty will be imposed on the excess loss over the corresponding guaranteed
loss (any or all). The penalty shall be calculated for the excess of no load loss and
for the excess of the load losses at rates specified above. For fraction of a KW the
penalty shall be applied prorate basis. If the test figure of. losses are less than the
guaranteed value, no bonus will be allowed. Any changes in the figure assigned for
transformer losses will not be permitted after opening of bids and bid evaluation will
be carried out on the basis of information made available at the time of bid opening.
15.0
SHORT CIRCUIT CALCULATIONS
15.1.
Manufacturer shall submit theoretical calculations in support of the ability to
withstand short circuit on consideration of highest value that may occur.
16.0
PERFORMANCE CERTIFICATES
Copies of performance certificates of sImilar Equipment supplied to various
utilities shall have to be furnished along with Tender
16.1.
17.0
LIST OF PAST SUPPLIES
The bidder shall furnish documents in support of Supply, Delivery of similar
Equipment indicating thereon names of the organization, quantity ordered, quantity
supplied along with tender.
17.1.
18.0
DESIGN, STANDARDIZATION AND GENERAL CONSTRUCTION FEATURES
18.1. .All material used shall be best quality and of the class most suitable for
working under the conditions specified and shall withstand the variations of
temperature and atmospheric conditions without distortion or deterioration or the
setting up of undue stresses which may impair suitability of the various parts for the
work which they have to perform.
18.2. Large parts, particularly removable ones, shall be interchangeable. Pipes and
pipe fittings, screws, studs, nuts and bolts used for external connections shall be as
per the relevant standards. Steel bolts and nuts exposed to atmosphere shall be of
hot deep galvanized
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
Nuts, bolts and pins used inside the transformers and tap changer
compartments shall be provided with lock washers or locknuts. Exposed parts shall
not have pockets where water can collect.
18.4. Internal design of transformer shall ensure that air is not trapped in any
location. Material in contact with oil shall be such as not to contribute to the
formation of acid in oil. Surface in contact with oil shall not be galvanized or
cadmium plated.
18.5. Labels, indelibly marked shall be provided for all identifiable accessories like
relays, switches, current transformers etc. All label plates shall be of in corrodible
material.
18.6. All internal connections and fastening shall be capable of operating under
overloads and over-excitation, allowed as per specified standard without injury.
18.7. Transformers and accessories shall be designed to facilitate proper
operation, inspection, maintenance and repairs. No patching, plugging, shimming or
other, such means of overcoming defects, discrepancies or errors will be accepted.
18.3.
19.0
CORES :
19.1. The Core shall preferably be boltless and step lap design and CRGO to be
procured directly from CRGO supplier or from their accredited agent supported by
necessary documentary evidence for.
19.2. Core shall have magnite coating as insulation. Successful bidder will offer the
core for inspection and/or approval by the purchaser during manufacturing stage.
19.3. Manufacturer’s call notice for the purpose should be accompanied with the
following documents as applicable as a proof towards use of prime core materials:
i)
ii)
iii)
iv)
v)
Invoice of the supplier
Mill‘s Test Certificate
Packing Lists
Bill of landing
Bill of entry Certificate to Customs Core materials shall be procured either
from the core manufacturer or through their accredited marketing
organisation of repute. Bidder should preferably have in-house Core cutting
facility for proper monitoring and Control on quality. The materials used for
insulation shall have high inter lamination resistance and rust inhibiting
property. It shall not have any tendency to absorb moisture or to react with
insulating oil.
19.4. The assembled core shall be securely clamped on the limbs and yoke with
uniform pressure so as to minimise noise emission form it.
19.5. The top main core clamping structure shall be connected to the tank body by
a copper strap. The bottom clamping structure shall be earthed by one or more of
the following methods
(i)
(ii)
(iii)
by connection through vertical tie rods to the top structure
by direct metal to metal contact with the tank base by the weight of
the core and windings,
by a connection to the top structure on the same side of core the main
earth connection to the tank.
19.6. All parts of the cores shall be robust design capable of withstanding any
shocks to which they may by subjected during lifting, transport, installation and
service.
19.7. Adequate lifting lugs shall be provided to enable the core and winding to be
lifted.
19.8. Adequate provision shall be made to prevent movement of the core and
winding relative to the tank during transport and installation or while in service.
19.9. The supporting frame work of the cores shall be so designed as to avoid the
presence of pockets which would prevent complete emptying of the tank through
the drain valve or cause trapping of air during filling.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
19.10. The insulation structure for the core to bolts and core to clamp plates shall be
20.0
such as to withstand a voltage of 2000 VAC at 50HZ for one minute
.
FLUX DENSITY OF CORE
20.1.
The maximum flux density in any part of the core and yokes at principal
(normal) tapping and at rated frequency shall not exceed 1.6 Tesla (16000 lines per
sq.cm) at normal voltage and 1.9 Tesla (19000 lines per sq.cm) under overvoltage
condition as specified in this specification.
20.2. Prior to inspection and testing of the Transformer the supplier shall submit
on request following curves of the core manufacturer.
i) Flux density vs Core loss.
ii) Flux density vs Excitatioin
21.0
WINDING:
21.1. All windings shall be fully insulated. 12.02 Power transformer shall be
designed to withstand the impulse and power frequency test voltages specified in
clause no. 9.01.
21.2.
The windings shall be designed to reduce to a minimum the out of balance
forces in the transformer at all voltage ratios.
21.3.
The insulation of Transformer winding and connections shall be free from
insulating material liable to soften, ooze out shrink or collapse and shall be noncatalytic and chemically inactive to transformer oil during service.
21.4. The stacks of windings shall receive adequate shrinkage treatment before
final assembly. Adjustable device shall be provided for taking up any possible
shrinkage of coils in service.
21.5.
All the insulating materials to be used in the transformer shall preferably be
of class- A insulation as specified in Indian Standards. The test certificate of the raw
materials shall be made available by the Transformer manufacturer on request
during inspection and testing.
21.6.
The coil clamping arrangement and the finished dimensions of any oil ducts
shall be such that it will not impede the free circulation of oil through the ducts.
21.7.
The windings and connection of transformer shall be braced to withstand
shocks which may occur during transport or due to switching short circuit and other
transient conditions during service.
21.8. Coil clamping rings, if provided shall be of steel or suitable insulating
material. Axially laminated material other than bakelised paper shall not be used.
22.0
INTERNAL EARTHING ARRANGEMENTS:
22.1.
General : All metal parts of the transformer with the exception of the
individual core laminations, core bolts and associated individual clamping plates
shall be maintained at fixed potential.
22.2.
Earthing of coil clamping rings : Where coil clamping rings are of metal at earth
potential, each ring shall be connected to the adjacent core clamping structure on
the same side of transformer as the main earth connection.
23.0
TANKS:
Construction : Conventional type tank shall be constructed. The Transformer
tank and cover shall be fabricated from good commercial grade low Carbon steel
suitable for welding and of adequate thickness. The tanks of all transformers shall
be complete with all accessories and shall be designed so as to allow the complete
transformer in the tank and filled with oil, to be lifted by crane or jacks, transported
by rail, road without overstraining any joint and without causing subsequent leakage
of oil.
23.2. The main tank body shall be capable of withstanding vaccum gauge pressure
68.0 KN per Sq, metres ( 500 mm. of HG).
23.1.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
The under carriage of the tank shall be made of channel of suitable size and
design. The base of each tank shall be so designed that it shall be possible to move
the complete transformer unit by skidding in any direction without injury when using
plate or rails.
23.4. Where the base is of a channel construction, it shall be designed to prevent
retention of water. Tank stiffeners shall be designed to prevent retention of water.
23.5. Wherever possible the Transformer tank and its accessories shall be
designed without pockets wherein gas may accumulate. Where pockets cannot be
avoided, pipes shall be provided to vent the gas into the main expansion pipe.
23.6. All joints other than those which may have to be broken shall be welded when
required they shall be double welded. All bolted joints to the tank shall be fitted with
suitable oil tight gaskets which shall give satisfactory service under the operating
conditions and guaranteed temperature rise conditions. Special attention shall be
given to the methods of making hot oil tight joints between the tank and the cover as
also between the cover and bushing and all other outlets to ensure that the joints
can be remade at site satisfactorily.
23.3.
24.0
TANK COVER
24.1. :Each tank cover shall be of adequate strength and shall not distort when
lifted. Inspection openings shall be provided as necessary to give easy access to
bushings or changing ratio or testing the earth connection. Each inspection opening
shall be of ample size for the purpose for which it is provided. The tank cover and
inspection cover shall be provided with suitable lifting arrangement.
24.2. The tank cover shall be fitted with pockets for thermometer and for the bulbs
of Oil and Winding temperature indicators. The thermometer pocket shall be fitted
with a captive screwed top to prevent the ingress of water. Protection shall be
provided, where necessary, for each capillary tube. The pocket shall be located in
the position of maximum oil temperature and it shall be possible to remove the
instrument bulbs without lowering the oil in the tank.
24.3. Turrets should provided on tank cover to house the bushings. The turrets of
both HV & LV bushings should be connected through pipes with main tank
Buchholtz Relay pipe to drive out trapped air or should have air release plug to drive
out trapped air as the case may be.
25.0
OFF LOAD TAP CHANGER.
25.1. The transformers shall be provided with voltage control equipment of the tap
changing type on the HV side for HV variation of +3% to (-) 9% in equal 5 steps of
3.0% for varying its effective transformation ratio whilst the transformers are offload. The tap changing device shall be off-circuit type. The tap changing shall be
carried out by means of an externally operated tapping switch capable of being
located and locked in any required position.
25.2. The location of tap changing device shall be such that an operator can very
easily change the tap, while standing on the ground without the aid of any climbing
platform. A warning plate indicating that switch shall not be operated in “ON”
position is to be provided.
25.3. The contact resistance between the contact points should be less than 20µΩ.
The manufacturer should show the resistance to the inspector at the time of
inspection.
26.0
CONSERVATOR VESSELS.
Conservator vessels : The conservator should be air cell/ atmoseal type to
prevent direct contact of Transformer oil with atmospheric air for retarding oxidation
contamination of oil. The Air cell shall be made from suitable material with inner
coating resistant to transformer oil & outer coating resistant to ozone & weathering.
26.2. The conservator shall be provided with necessary valves to drive out the air
in the space between conservator wall & air cell during filling of oil, drain valves for
complete draining of oil and cut off valves etc.
26.1.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
The conservator complete with necessary valves shall be provided in such a
position as not to obstruct the electrical connections to the transformer from H.V &
L.V SIDE.
26.4. The conservator shall be a capacity to meet the requirement of expansion of
the total cold oil volume in the Transformer & cooling equipment.
26.5. The conservator shall be designed so that it can drain oil completely by
means of the drain valve provided when mounted. One end of the conservator shall
be bolted into position so that it can be removed for cleaning purpose.
26.6. The conservator shall be provided with different valves for filling of oil
manually at site.
26.3.
27.0
OIL GAUGES
27.1.
Normally one Magnetic type oil gage shall be provided. The oil level at 30
Deg. C. shall be marked on the guage.
27.2. CONNECTION : The oil connection from the transformer tank to the
conservator vessel shall be arranged at a raising angle of 3 to 9 degrees to the
horizontal up to the Buchholtz Relay and shall consist of pipe with inside diameter
50 mm./80 mm. as per capacity of the Transformer and as per IS:3639.
27.3. Two valves shall be provided between the conservator & Transformer main
tank to cut off the oil supply to the transformer after providing a straight run of pipe
for at least a length of five times the internal diameter of the pipe on the tank side
ofthe Gas and Oil actuated Relay and at least three times the internal diameter of the
pipe on the conservator side of the Gas and Oil actuated Relay. The valves should
be fitted on both side of the Gas and Oil Actuated Relay.
28.0
BREATHER :
Each conservator vessel shall be fitted with a glass container type breather in
which silicagel is dehydrating agent and so designed that the passage of air through
the silicagel the external atmosphere is not continuously in contact with the oil.
28.1.
.
28.2. The moisture absorption indicated by a change in colour of the tinted crystals
can be easily observed from the distance.
28.3.
All breathers shall be mounted at approximately 1400 mm above ground level
and shall be connected to the air cell of the conservator through pipe for the
purpose of breathing during contraction or expansion of the air cell.
29.0
BUSHINGS
29.1.
Bushings for 36 KV and below shall be of solid porcelain type. These
bushings shall be suitable for bare ACSR conductor connections.
29.2. The bushing shall have sufficient insulation to avoid leakage to ground and
shall be so located as to provide adequate electrical clearance between bushing or
various voltages and between bushings and grounded parts. The insulation class of
the high voltages neutral bushing shall be properly co-ordinated with the insulation
class of the neutral of the high voltage winding.
29.3. Stresses due to expansion and contraction in any part of the bushing
insulator shall not lead to the development of defects. Outdoor insulators and
fittings shall be unaffected by atmospheric conditions due to weather, fuses, ozone,
acids, dust and rapid changes of air temperature. Any stress shield shall be
considered as integral part of the bushing assembly.
29.4. Porcelain shall not engage directly with hard metal and where necessary
gaskets shall be interposed between the porcelain and the fittings. All porcelain
clamping surface in contact with gasket shall be accurately grounded and free from
glaze
29.5. Fixing material used shall be of suitable quality and properly applied and
shall not enter into chemical action with the metal parts or cause fracture by
contraction expansion in service. Cement thickness shall be as small and even as
possible and proper care shall be taken to centre and locate individual parts
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Technical Specification
correctly during cementing. All porcelain insulators shall be designed to facilitate
clearance.
29.6. Each porcelain bushing or insulator, and paper bushing shall have marked
upon it the manufacturer‟s identification mark, and such other marks as may be
required to assist in the representative selection of batches for the purpose of the
sample tests.
29.7. Clamps and fittings shall be made of steel and galvanized. The bushing
flanges shall not be re-entrant type (shape) which may trap air.
29.8. Each bushing shall be so coordinated with the transformer insulation, that
the flashover will occur outside the tank.
29.9. All porcelain used in bushings shall be of wet process, homogeneous and
free from cavities or other flaws. The glazing shall be uniform in colour (brown) and
free from blisters, burns and other defects. Porcelain shall be thoroughly vitrified
and shall be impervious to moisture.
29.10. All bushing shall have puncture strength greater than dry flashover value.
29.11. Creepage distance will be kept 27 mm/KV. Bushings may be provided with
weather shield.
29.12. The bidder is requested to give the guarantee withstand voltage for the above
and also furnish a calibration curve with different settings of the co-ordination gap
to enable the purchaser to decide the actual gap settings. Tenderer‟s
recommendations are also invited to this respect. During spark gap flashover, the
arc shall remain away from the housing insulator.
29.13. Each terminal (including neutral) shall be distinctly marked and coloured for
phase voltage and phase rotation on the primary secondary and tertiary sides in
accordance with the diagram of connection supplied with the transformer, the
system of marking shall conform IS 2026-1962 amended upto date.
29.14. Stress due to expansion and contraction in any part of the bushing shall not
lead to deterioration.
29.15. Bushing shall be designed and tested to comply with the applicable
standards.
29.16. Bushings rated for 400A and above shall have non-ferrous flanges and
hardware.
29.17. Fittings made of steel or malleable iron shall be galvanized.
29.18. Bushing shall be so located on the transformer that full flashover strength
will be utilized. Minimum clearances as required for the BIL shall be realized
between live parts and live parts to earthed structures.
29.19. All applicable routine and type tests certificates of the bushings shall be
furnished for approval.
29.20. Bushings shall be supplied with bimetallic/terminal connectors/ clamp
suitable for fixing to bushing terminal and the PURCHASER‟S specified conductors.
The connectors/clamp shall be rated to carry the bushing rated current without
exceeding a temperature rise of 55° C over an ambient of 40° C. the connector/
clamp shall be designed to be corona free at the maximum rated line to ground
voltage.
29.21. Bushing of identical voltage rating shall be interchangeable.
29.22. Each bushing shall be so coordinated with the transformer insulation that all
flashover will occur outside tank.
30.0
FILTER AND DRAIN VALVES, SAMPLING DEVICES AND AIR RELEASE PLUGS :
30.1.
Each Transformer shall be fitted with the following :
30.2. The filter and drain valves as specified.
 A drain valve as below shall be fitted to each conservator. For diameter upto
650 mm : Size of the valve 15 mm : for diameter above 650 mm : Size of the
valve 25 mm.
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Technical Specification
 Suitable oil sampling device shall be provided at the top and bottom of the
main tank. The sampling device shall not be fitted on the filter valves
specified
above.
 One 15mm air release plug on the main tank of the Transformer.
30.3.
All other valves opening to atmosphere shall be fitted with blank flanges.
Valves shall be of forged carbon steel upto 50 mm size and of gun metal or of cast
iron bodies with gun metal fittings for sizes above 50 mm. They shall be of full way
type with screwed ends and shall be opened by turning counter clock wise when
facing the hand wheel. There shall be no oil leakage when the valves are in closed
position.
30.4. Each valve shall be provided with an indicator to show the open and closed
position and shall be provided with facility for padlocking in either open or closed
position. All screwed valves shall be furnished with pipe plugs for protection.
Padlocks with duplicate keys shall be supplied along with the valves.
30.5. All valves except screwed valves shall be provided with flanges having
machined faces drilled to suit the applicable requirements. Oil tight blanking plates
shall be provided for each connection for use when any radiator is detached and for
all valves opening to atmosphere. If any special radiator valve tools are required, the
Contractor shall supply the same. The main tank Valves shall be provided with suitable
Iron cage Gaurd so that the valve doesnot get damage during transportation and not easily
accesible to operate.
30.6. Each transformer shall be provided with following valves on the tank so
located as to completely drain the tank.


30.7.
30.8.
31.0
Two filter valves on diagonally opposite corners, of 50 mm size.
Oil sampling valves not less than 8 mm at top and bottom of main tank
Valves between radiators and tank.
Valve prior to and after the Buchholz Relay.
COOLING PLANT
31.1. General :Radiators shall be so designed as to avoid pockets in which
moisture may collect and shall withstand the pressure tests.
31.2. The radiator tubes / fins shall be seamless, made of mild steel having as
minimum wall thickness of approx. 1.2mm and a clean bright internal surface free
from dust and scale. They shall be suitably braced to protect them from mechanical
shocks, normally met in transportation and to damp the modes of vibration
transmitted by the active part of the transformer in service.
31.3.
Each cooler unit shall have a lifting eye.
31.4. Radiator Valves: The butterfly or similar metal valves shall be provided for
isolating detachable radiator assembly.
31.5. One cock each at the bottom of radiator stack shall be provided for draining
oil from radiator stacks.
31.6. Air release plug each at the top of radiator stack shall be provided for
release of air from radiator stack.
31.7. Removable blanking plates shall be provided to permit the blanking off the
main oil Connection of each cooler.
31.8. Radiator fixing bands in top & bottom of radiators are to be provided to
minimise the vibration of the same.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
32.0
33.0
LIFTING AND HAULAGE FACILITY :
32.1.
Each tank shall be provided with Lifting lugs suitable for lifting of transformer
complete with oil.
32.2. A minimum of four jacking lugs, in accessible positions to enable the
transformer complete with oil to be raised or lowered using hydraulic or screw jacks
32.3. The minimum height of the lugs above the base shall be as follows
(a) for transformers up to and including 10 tones weight-300mm
(b) for Transformers above 10 tones weight – 500 mm
32.4. Suitable haulage holes shall be provided.
INSULATING OIL :
33.1. The Transformer and all associated oil filled Equipment shall be supplied
complete with insulating new oil required for first filling including 10% extra oil for
future use during commissioning. The Transformer tank shall be dispatched
completely filled with oil and the balance oil shall be supplied in non returnable
sealed drums along with the Transformers.
33.2. The Insulating oil shall conform to the requirement of IS:335.
34.0
PRESSURE RELIEF DEVICE :
34.1. Pressure relief device shall be provided of sufficient sizes for rapid release of
pressure that may by generated within the tank, and which might result in damage
to the equipment. The device shall operate at a static pressure of less than the
hydraulic test pressure for transformer tank. Means shall be provided to prevent
ingress of rain.
34.2. It shall be mounted on the cover of the main tank and shall be designed to
prevent gas accumulation.
34.3. Spring loaded setting type Pressure Relief Valve having suitable opening
Port hole according to the capacity of the transformers should be provided.
34.4. The pressure relief valve should have provision of visual indication for
opening of the valve and also Contract/Micro Switch arrangement for
alarm/Tripping Function.
35.0
AXLES AND WHEELS :
35.1. The Transformer shall be provided with flanged bi-directional wheels as
mentioned below :
Flanged wheel suitable for use on a 1435 mm / 1676 mm guage track.

.
The wheels shall be suitable for being turned through an angle of 90 Deg.
and locked in that position when the tank is jacked up.
35.3. All wheels shall be detachable and shall be made of Cast Iron or Steel.
Suitable locking arrangement shall be provided to prevent the accidental movement
of the transformer.
35.2.
36.0
CLEANING & PAINTING
36.1. Before painting or filling with oil all galvanised parts shall be completely
cleaned and free from rust, scale and grease and all external surface cavities on
castings shall be filled by metal deposition.
36.2. The interior of all transformer tanks and other oil filled chambers and internal
structural steel work shall be thoroughly cleaned of all scale and rust by sand
blasting or other approved method. These surfaces shall be painted with hot oil
resisting varnish or paint. Unexposed welds need not be painted.
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Technical Specification
36.3. Except for nuts, bolts and washers, which may have to be removed for
maintenance purposes, all external surfaces shall receive a minimum of three coats
of paint.
36.4. The primary coat shall be applied immediately after cleaning. The second
coat shall be of oil paint of weather resisting nature and preferably of a shade or
colour easily distinguishable from the primary and final coasts shall be applied after
the primarycoats have been touched up where necessary.
36.5. The final coat shall be of glossy oil and weather resisting non fading paint of
Dark Admiralty Grey shade no. 632 of IS:5.
36.6. Primer paint shall be ready made zinc chrome as per IS: 104: Intermediate
and final costs of paint shall be as per IS: 2932.
36.7. All interior surfaces of mechanism chambers and kiosks except those which
have received anti-corrosion treatment shall receive three coats of paint applied to
the thoroughly cleaned metal surface as per procedure mentioned above. The final
coat shall be of a light coloured anti-condensation mixture.
36.8. Any damage to paint work incurred during delivery shall be made good by
the manufacturer by thoroughly cleaning the damage portion and applying the full
number of coats of paint that had been applied before the damage was caused.
37.0
EARTHING TERMINAL
37.1. Two earthing terminals capable of carrying the full amount of lower voltage
short circuit current of transformer continuously for a period of 5 Second Provision
shall be made at positions close to each of the bottom two corners of the tank for
bolting the earthing terminals to the tank structure to suit local condition.
38.0
TEMPERATURE INDICATING DEVICE:
38.1. Oil temperature indicator with two electrical contacts for alarm and trip
purposes, shall be provided with anti vibration mounting. The oil temperature
indicator shall be housed in the marshalling box.
38.2.
The winding temperature indicator with two electrical contacts for alarm &
trip purposes shall be provided with anti vibration mounting. The winding
temperature indicator shall be housed in the marshalling Box.
38.3. The Oil and Winding temperature indicator should be of renowned make
preferably of ―Perfect Control‖ or ―Precimeasure‖. The scale on the dial of the
thermometer should be 0°C to 150°C. The angular displacement of thermometer
should be 270 Deg.
38.4. The signaling contact of WTI & OTI shall be set to operate at the following
temperature:
OIL :
Alarm-85 °C, Trip – 95 ° C
WINDING : Alarm-100 °C, Trip – 110 °C
The tripping contacts of indicator shall be adjustable to close the winding
temperature indicator between 60 Deg.C and 120 Deg.C. The alarm contacts of
indicator shall be adjustable to close between 50 deg.C & 100 Deg.C.
38.6.
All contacts shall be adjustable on a scale and shall be accessible on
removal of the cover. The Temperature indicators shall be so designed that it shall
be possible to check the operation of contacts and associated Equipments.
38.7.
For measuring winding temperature a heater coil fed from a C.T. has to be
provided on the pocket for winding temperature indicator bulb. The connection from
C.T. to heater should be through a link arrangement on the tank cover suitably
housed in a weather proof box so that C.T. current and heater coil resistance can
be checked. WTI C.T. secondary should be of 5 Amps, rating.
38.8.
Accuracy class of both OTI and WTI shall be ±1% or better.
38.5.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
39.0
MARSHALLING BOX
39.1.
A sheet steel 3.15mm thick vermin proof, well ventilated and weather
proof marshalling box of a suitable construction shall be provided for the
transformer ancillary apparatus. The box shall have domed or sloping roofs
and the interior & exterior painting shall be in accordance with painting
clause specified. The degree of protection shall be IP-55.
39.2. The marshalling box shall accommodate.
 Winding and oil temperature indicator.
 Terminal Blocks and gland plates for incoming and outgoing Cables.
 One space heater operated by 220 V.A.C. Aux. Supply, Cubicle illuminating
lamp with door switch.
39.3. All incoming cables shall enter the kiosk from the bottom and the gland
plate shall not be less than 450 mm from the base of the box. The gland plate
and associated compartment shall be sealed in suitable manner to prevent
the ingress from the cable trench
39.4. All the above equipment shall be mounted on panels and back of panel
wiring shall be used for Interconnection. The temperature indicators shall be
so mounted that the dials are visible by standing at ground level.
39.5. Door of the compartment shall be provided with glass window of
adequate size. Ventilation louvers shall be provided.
39.6. The schematic diagram of the circuitry inside the marshalling box be
prepared and fixed inside the door
40.0
GAS AND OIL ACATUATED RELAYS
40.1. Each transformer shall be provided with gas and oil actuated Relay
(Buchholtz Relay) equipment conforming of IS:3637 double float type with one set
of alarm contacts, one set of trip contacts and a testing pet cock. The contacts shall
be wired with a P.V.C. armoured cable.
40.2. A machined surface shall be provided on the top of Relay to facilitate the
setting of Relay and to check the mounting angle in the pipe and cross level of the
Relay.
40.3. The pipe work shall be so arranged that all gas arising from the Transformer
shall pass into the gas and oil actuated Relay. The oil circuit through the Relay
shall not form a delivery path in parallel with any circulating oil pipe.
RATING DIAGRAM AND PROPERTY PLATES :
41.1. The following plates shall be fixed to the transformer tank at a suitable height
so that the particulars could be read by standing at ground level.
41.2.
A rating plate bearing the data specified in the relevant clauses of IS:2026
including figures of temperature rise of oil and winding and high voltage test values.
that the equipment belongs to APDCL with reference of purchase order is also to
be indicated.
41.3.
A diagram plate showing the internal numbering of taps, tapping switch
connection of windings and also the voltages vector relationship in accordance with
IS:2026 and in addition a plan view of the transformer giving the correct physical
relationship of the terminals. No load voltage shall be indicated for each tap. Details
of C.T particulars w.r.o phase, Neutral &WTI CT.
41.0
42.0
CENTRE OF GRAVITY :
42.1. : The centre of gravity of the assembled transformer shall be low and as near
the vertical centre line as possible. The transformer shall be stable with or without
oil.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
42.2.
If the centre of gravity is eccentric relative to track either with or without oil,
its location shall be shown on the outline drawing.
.
43.0
44.0
FOUNDATION :
43.1. The tenderer shall furnish foundation plan of the transformer showing the
fixing arrangement of the transformer so that the purchase may be able to finalise
the foundation drawings.
TEST AND INSPECTION :
44.1. Routine Tests :
44.2. All transformers shall be subjected to the following routine tests at the
manufacturer‘s works. The tests shall be carried out in accordance with the details
specified in IS:2026.
i) Measurement of winding resistance.
ii) Measurement of turns ratio for all sets wndings on each tap
iii) Polarity and phase vector relationship.
iv) Measurement of no load loss and no load current.
v) Measurement of impedance voltage at normal , maximum and minmum
tap
vi) Measurement of insulation resistance between windings and between
windings and earth
vii) Measurement of load loss.
viii) Induced over voltage withstand test.
ix) Separate source voltage withstand test.
x) Oil Leakage gas collection, oil surge and voltage test on gas and oil actuated
relay for on load tap changer.
xi) Magnetic balance test.
xii) Testing of Phase & Neutral C.T., as applicable, in accordance with provisions
in the relevant I.S.
xiii) Oil leakage test of tnansformer tanks at a pressure equals to the normal
pressure plus 35 KN/ sq.M measured at the base of tank.
44.3. Type Test
44.4. In addition to routine Tests mentioned above the transformer shall be
subjected to all kinds of Type and Acceptance Test in accordance with Relevant
I.S. (IS:2026) with latest amendment if any.
44.5.
Bidder should submit Type Test report from NABL/Govt. approved
Laboratories along with their offer having identical technical parameters as
that of the tendered item failing which their offer may not be technically
accepted.
44.6.
However, if it is found that the bidder has submitted Type tests Report
but those have not been conducted on identical Design of equipment/material
as per specification of APDCL, the same may be accepted subject to the
following conditions: APDCL at his discretion request the successful bidders
to conduct Type Tests on identical design as per specification
44.7. . Such Type tests/special tests, if required to be carried out at
NABL/Govt. approved Laboratories in presence of APDCL engineers for
which no extra cost shall be charged to the APDCL.
44.8.
However, the bidders who have not submitted such Type Test/Dynamic
Short Circuit Test report but if their offer is considered technically acceptable by the
purchasers on the basis of other credentials, they will have to carry out such tests
at NABL/Govt. approved Laboratories in presence of APDCL engineers before
effecting physical delivery against Purchase Order for which no extra cost shall be
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
charged to the APDCL. Routine Test have to be carried out in presence of
APDCL engineers before carrying out type test.
45.0
46.0
47.0
INSPECTION AND TESTING
45.1. Inspection and testing as already mentioned the equipment shall be
subjected to routine and other acceptance tests as per provisions in the relevant
I.S.
45.2. The APDCL reserves the right to send its Engineers if so desires to witness
manufacturing process and to reject either raw materials or finished products found
to be not complying with the requirement of the specification and also shall have
the right to select any/all equipment from the lot offered for tests.
45.3. The manufacturer shall give at least (21) twenty one days’ advance notice
regarding readiness of such inspection and testing and shall submit six sets of the
works test certificates of the materials/equipment offered for inspection and testing
indicating probable date of inspection and testing.
45.4. The manufacturer shall arrange all possible facilities for such inspection and
testing at any time during the course of manufacture free of cost.
TEST CERTIFICATE
46.1. Five copies of the approved Test Certificates as mentioned above are to be
furnished to the APDCL before dispatch of the equipment.
DRAWINGS AND MANUALS TO BE SUBMITTED BY SUCCESSFUL BIDDER
47.1. The bidder shall furnish, within fifteen days after issuing of letters Award, six
copies each of the following drawings/documents incorporating name of project and
transformer rating for approval.
i. Detailed overall general arrangement drawing showing front and side
elevations and plan of the transformer and all accessories including
radiators and external features with details of dimension, spacing of wheels
in either direction of motion, net weights and shipping weights, crane lift for
untanking, size of lugs and eyes, bushing lifting dimensions, clearances
between HV and LV terminals and ground, quantity of insulating oil etc.
ii. Foundation plan showing loading on each wheel and jacking points with
respect to centre line of transformer.
iii. GA drawing/details of bushing and terminal connectors.
iv. Name plate drawing with terminal marking and connection diagrams.
v. Wheel locking arrangement drawing.
vi. Transportation dimension drawings.
vii. Interconnection diagrams.
viii. Over fluxing withstand time characteristics of transformer.
ix. GA drawing of marshalling box.
x. Control scheme/wiring diagram of marshalling box.
xi. Technical leaflets of major components and fittings.
xii. As built drawing of schematic, wiring diagrams etc.
xiii. Setting of oil temperature indicator, winding temperature indicator.
xiv. Completed technical data sheets.
xv. HV/LV conductor bushing.
xvi. Bushing assembly.
xvii. Bi-metallic connector for connection to ―Wolf‖/PANTHER ACSR/AAAC
conductor
xviii. Radiator type assembly.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
47.2.
All drawings/documents, technical data sheets and test
certificates/results/calculations shall be furnished.
47.3.
Any approval given to the detailed drawings by the purchaser shall not
relieve the contractor of the responsibility for correctness of the drawing and
in the manufacture of the equipment. The approval given by the purchaser
shall be general with overall responsibility with contractor.
47.4.
Installation, operation and maintenance manual of transformer,
associated equipment like buchholtz Relay, temperature indicators, oil level
indicator etc. The manual shall clearly indicate the installation method,
check-ups and tests to be carried out before and after commissioning of the
transformer.
47.5.
One copy of manual, set of approved drawings shall be submitted to
the CGM(PPD)/APDCL before dispatch of the Transformer.
47.6.
In addition one set of approved drawing, manual for transformer shall
be send to the respective consignee officer in water proof folder at the time of
delivery of the transformer.
48.0
GUARANTEED TECHNICAL PARTICULARS
48.1. Bidder shall furnish guaranteed technical particulars of equipment offered as
per Schedule ‗B‘ To be provided along with final NIT specification),
49.0
ACCESSORIES
49.1. All accessories as specified in the schedule A are to be provided. Any other
part necessary for smooth operation of the transformer if omitted it is the
manufacturers responsibility to include the same.
SPARE PARTS:
50.1. The Tenderer shall submit a recommended list of spare parts for five years
of operation along with item wise price for each item of spares as stated in
Schedule B
50.0
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
SCHEDULE – A
FITTINGS & ACCESSORIES
The following fittings and accessories shall be supplied with each Transformer :
1. Outdoor type bushing – 11KV-3 Nos. and LV-4 Nos.
2. Conservator with aircell and supporting bracket or structure as the case may
be.
3. Isolating valve for conservator in between conservator and Buchholtz Relay
and in between Buchholtz relay and main tank..
4. Conservator valves for driving out air between air cell & wall of conservator &
connection to breather.
5. Conservator drain valve.
6. Dial type oil level indicator complete with alarm contact.
7. Silica gel breather with oil seal and connecting pipe. The breather shall be
accessible for inspection from ground.
8. Spring loaded setting type pressure relief Valve having suitable opening Port.
Hole & provision of visual indication for opening of the valve & Alarm/Trip contact
arrangement.
9. Access/inspection holes with bolted cover for access to inner ends of bushing.
10. Cover lifting eyes.
11. Lifting eyes for core frame with windings.
12. Tap changing arrangement with hand wheel for Off-Load tap13. Air release plugs on top of cover and pressure equalizer pipe for bushing
turret.
14. Upper filter valve and bottom filter valve with cage valve guard..
15. Drain valve with cage gaurd.
16. Top and bottom oil sampling devices. Provision for oil sample collection
during process of filtration should be made.
17. Lifting lugs.
18. Jacking pads with handling holes at four corners.
19. Transport lugs.
20. Under carriage base channel.
21. Tank earthing terminals – 2 Nos.
22 Buchholtz relay double float type with one set of alarm contacts, one set of trip
contacts and testing pet cock. The contacts should be wired with a PVC
armoured cable.
23. Dial thermometer for winding temperature with alarm contacts and Trip
contacts.
24. Dial thermometer for oil temperature with alarm contacts and Trip Contacts.
25. An additional pocket for inserting thermometer for oil temperature indication.
26. Weather proof control cabinet for marshalling terminal connections from
protective and indicative devices. The cabinet shall be provided with
incandescent filament lighting, heater and plugs etc.
28. Rating plate, as per I.S.S.
29. Diagram Plate : As per clause 28.
30. Property label.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
SCHEDULE – B
SPARE PARTS:
The mandatory spare parts shall include but not be limited to the following for each
rating of transformer.
(i)
Bushings:
a. High Voltage
- 1 No.
b. Low Voltage
- 1 No.
c. Neutral Bushing
- 1 No.
(ii)
Complete set of gaskets for all
- 1 Set
openings on the tank requiring gasket.
(iii)
Magnetic oil level gauge with low oil
- 1 No.
level alarm contacts.
(iv)
Oil temperature indicator with alarm
- 1 No.
and trip contacts and maximum reading pointer.
(v)
Winding temperature indicator with alarm and trip
- 1 No.
contacts and maximum reading pointer
(vi)
Set of all types of valves comprising one in each type. - 1 Set
(vii) Silicagel breather
- 1 No.
(viii) Buchholz Relay
- 1 No.
Note: The quantities indicated above are for each transformers.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
Section – 3
3.1
GENERAL TECHNICAL SPECIFICATIONS
1.0 Part A General:
1.1. It is not the intent to specify herein complete details of design and construction
of the plant/equipment/material. The plant offered shall conform to the relevant
standards and shall be of high quality, sturdy, robust and of good design and
workmanship complete in all respects and capable to perform continuous and
satisfactory operations in the actual service conditions at site and shall have
sufficiently long life in service. The dimensional drawings attached with the
technical Specification in Volume II are generally of illustrative nature. In actual
practice, not withstanding any anomalies, discrepancies, omissions,
incompleteness, etc. in these specifications and attached drawings, the design
and constructional aspects, including materials and dimensions, will be subject
to good engineering practice in conformity with the required quality of the
product and to such tolerances, allowances and requirements for clearances
etc. as are necessary by virtue of various stipulation in that respect in the
relevant Indian Standards, IEC standards, I.E. Rules and other statutory
provisions.
1.2. The plant/equipment/material offered shall be complete with all parts necessary
for their effective and trouble free operation. Such parts will be deemed to be
within the scope irrespective of whether they are specifically indicated in the Bid
documents or not.
2.0 Quality Assurance Programme:
2.1. Bidder must establish that a proper quality assurance program is being followed
by them for manufacture of plant/equipment. Quality Assurance Program must
have a structure as detailed in following paragraphs.
2.2. Quality assurance and failure prevention starts with careful study and scrutiny of
our technical specifications and requirements. Bidder/manufacturer shall
carefully study all the technical parameters and other particulars and the
Bidder/manufacturer shall categorically give his confirmation that these
requirements shall be met in a satisfactory manner.
2.3. Bidder/manufacturer shall furnish the checks exercised in design calculations.
The salient features of design shall be made available to the Employer.
2.4. Bidder/manufacturer shall indicate the various sources of the items being
procured. Type of checks, quantum of checks and acceptance norms shall be
intimated and random test and check results should be made available for
inspection whenever so desired.
2.5. The Bidders shall invariably furnish following information.
1. Statement giving list of important raw materials, names if subBidder/manufacturers for the raw material, list of standards according to
which the raw material is purchased and copies of test certificates thereof.
2. Information and copies of test certificates as in (i) above in respect of
bought out items.
3. List of machines and manufacturing facilities available.
4. Levels of automation achieved and list of areas where manual
processing exists.
5. List of areas in manufacturing process, where stage inspections are
normally carried out for quality control and details of such tests and
inspections.
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Technical Specification
6. List of testing equipment available with the Bidder for final testing of
materials specified and test plant limitation, if any, vis-a-vis type, special,
acceptance and routine tests specified in the relevant standards. These
limitations shall be very clearly brought out in schedule of deviations from
specified test equipments.
3.0 Pre Dispatch Inspection:
3.1. The Employer‘s representative may carry out stage inspection of the
plant/equipment during manufacturing/ assembling stage. The Employer shall
have absolute right to reject the raw material/ component/ sub assemblies or
complete equipment not found to be conforming to the specification or being of
poor quality/ workmanship. The stage inspection will particularly include tests
specified for any particular plant or equipment in the technical specification,
general routine tests and physical measurements to be conducted during
manufacturing stages as per manufacturer‘s standard practice.
3.2. The Bidder/manufacturer shall give fifteen (15) days advance notice to enable
the Employer to arrange for inspection. Inspection and testing shall be
conducted at the place of manufacture. Inspection and testing of any material
under this specification by the Employer shall not relieve the
Bidder/manufacturer of his obligation to supply the plant/equipment in
accordance with the specification and shall not prevent subsequent rejection if it
is found to be defective.
3.3. The Bidder/manufacturer shall afford the Employer‘s representative all
reasonable facilities, without charge, to satisfy him that the plant/ equipment is
being manufactured in accordance with the specifications. The
Bidders/manufacturer must have adequate set of instruments for conducting
tests as per ISS specification. Instruments shall be duly calibrated and
calibration certificate should not be older than one year on the date of
inspection. Calibration shall be done by NABL accredited laboratories. A
comprehensive list of testing equipment/ instruments indicating make, Sr.No.,
type, class of accuracy, calibrating agency, calibration date etc. should be
furnished, as and when desired. Calibrated instruments shall be duly sealed by
calibrating agency to avoid any tampering with calibration and the details
thereof shall be clearly mentioned in the calibration certificate(s).
4.0 Defect Liability:
4.1. The defect liability period of plants/ equipments shall be as indicated in GCC
of the bid document Vol. I.
SPECIAL TECHNICAL SPECIFICATIONS FOR NEW SUBSTATION CIVIL WORKS
& SWITCHGEAR
1.0
GENERAL
The intent of specification covers the following:
Design, engineering, and construction of all civil works at sub-station. All civil works shall
also satisfy the general technical requirements specified in other Section of this
Specification and as detailed below. They shall be designed to the required service
conditions/loads as specified elsewhere in this Specification or implied as per
National/International Standards.
All civil works shall be carried out as per applicable Indian Laws, Standards and Codes. All
materials shall be of best quality conforming to relevant Indian Standards and Codes.
The Contractor shall furnish all design, drawings, labour, tools, equipment, materials,
temporary works, constructional plant and machinery, fuel supply, transportation and all
other incidental items not shown or specified but as may be required for complete
performance of the Works in accordance with approved drawings, specifications and
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Technical Specification
direction of Employer.
The work shall be carried out according to the design/drawings to be developed by the
Contractor and approved by the owner based on Tender Drawings Supplied to the
Contractor. by the Owner. For all buildings, structures, foundations, etc., necessary layout
and details shall be developed by the Contractor keeping in view the functional
requirement of the substation facilities and providing enough space and access for
operation, use and maintenance based on the input provided by the Owner. Certain
minimum requirements are indicated in this specification for guidance purposes only.
However, the Contractor shall quote according to the complete requirements.
1.2 GEO-TECHNICAL INVESTIGATION
1.3 The Contractor shall perform a detailed soil investigation to arrive at sufficiently accurate,
general as well as specific information about the soil profile and the necessary soil
parameters of the Site in order that the foundation of the various structures can be
designed and constructed safely and rationally.
A report to the effect will be submitted by the contractor for Owner's specific approval
giving details regarding data proposed to be utilized for civil structures design.
2.0 SCOPE OF WORK
This specification covers all the work required for detailed soil investigation and
preparation of a detailed report. The work shall include mobilization of necessary
equipment, providing necessary engineering supervision and technical personnel, skilled
and unskilled labour, etc., as required to carry out field investigation as well as, laboratory
investigation, analysis and interpretation of data and results, preparation of detailed GeoTechnical report including specific recommendations for the type of foundations and the
allowable safe bearing capacity for different sizes of foundations at different founding
strata for the various structures of the substation. The Contractor shall make his own
arrangement for locating the co-ordinates and various test positions in field as per the
information supplied to him and also for determining the reduced level of these locations
with respect to the benchmark indicated by the Owner.
All the work shall be carried out as per latest edition of the corresponding Indian Standard
Codes.
2.1 Bore Holes
Drilling of bore holes of 150 mm dia, in accordance with the provisions of IS: 1982 at the
rate of minimum two number of bore holes per bay to 15 m depth or to refusal which ever
occur earlier. (By refusal it shall mean that a standard penetration blow count (N) of 100 is
recorded for 30 cm penetration). However, in case deep pile foundations are envisaged
the depths have to be regulated as per codel provisions. In cases where rock is
encountered, coring in one borehole per bay shall be carried out to 3 M in bedrock and
continuous core recovery is achieved.
Performing Standard Penetration Tests at approximately 1.5 m interval in the borehole
starting from 1.5 m below ground level onwards and at every change of stratum. The
disturbed samples from the standard penetrometer shall also be collected for necessary
tests.
Collecting undistributed samples of 100/75 mm diameter 450 mm long from the boreholes
at intervals of 2.5 m and every change of stratum starting from 1.0 m below ground level
onwards in clayey strata.
The depth of Water Table shall be recorded in each borehole.
All samples, both disturbed and undisturbed, shall be identified properly with the borehole
number and depth from which they have been taken.
The sample shall be sealed at both ends of the sampling tubes with wax immediately after
the sampling and shall be packed properly and transported to the Contractor's laboratory
without any damage or loss.
The logging of the boreholes shall be compiled immediately after the boring is completed
and a copy of the bolero shall be handed over to the Engineer-in - Charge,
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Technical Specification
2.2 Dynamic Cone Penetration Test
Dynamic cone penetration tests of two numbers shall be carried out with the circulation of
bentonite slurry at specified locations and a continuous record of penetration resistance
(NG) upto 15.00 meter from natural ground level or the refusal shall be maintained by the
Contractor IS: 4968 (Part-2) shall be followed for carrying out the test and reporting
results.
The location for tests shall be as directed by the Owner. On completion of the test, the
results shall be presented as a continuous record as the numbers of blows required for
every 300 mm penetration of the cone into the soil.
2.3 Trial Pits
Trial pits shall be carried at specified one locations of per bay as directed by the Owner.
The trial pits shall be 2m x 2m in size extending to 4 m depths, or as specified by the
Owner. Undisturbed samples shall be taken from the trial pits as per the direction of the
Owner.
2.4 Electrical Receptivity Test
This test shall be conducted to determine the Electrical receptivity of soil required for
designing safe grounding system for the entire station area. The specifications for the
equipments and other accessories required for performing electrical receptivity test, the
test procedure, and reporting of field observations shall confirm to IS: 3043. The test shall
be conducted using Wagner's four electrode method as specified in IS: 1892, AppendixB2. Unless otherwise specified at each test location, the test shall be conduced along two
perpendicular lines parallel to the co-ordinate axis. On each line a minimum of 8 to 10
readings shall be taken by changing the spacing of the electrodes from an initial small
value of 0.5 m upto a distance of 10.0 m.
2.5 Plate Load Test
Plate load test shall be conducted to determine the bearing capacity, modulus of subgrade reaction and load/settlement characteristics of soil at shallow depths by loading a
plane and level steel plate kept at the desired depth and measuring the settlement under
different loads, until a desired settlement takes place or failure occurs. The specification
for the equipment and accessories required for conducting the test, the test procedure,
field observations and reporting of results shall conform to IS: 1888. Modulus of sub-grade
reaction shall be conducted as per IS: 9214. The location and depth of the test shall be as
given below:
1) One at Control Building location at the proposed foundation depth below finished
ground level for bearing capacity.
2) One test at Transformer foundation location at proposed foundation depth below
FGL.
Undisturbed tube samples shall be collected at 1.0 m and 2.5 m depths from natural
ground level for carrying out laboratory tests.
The size of the pit in plate load test shall not be less than five times the plate size and shall
be taken upto the specified depth. All provisions regarding excavation and visual
examination of pit shall apply here.
Unless otherwise specified the reaction method of loading shall be adopted. Settlement
shall be recorded from dial gauges placed at four diametrically opposite ends of the test
plate.
The load shall be increased in stages. Under each loading stage, record of time Vs.
Settlement shall be kept as specified in IS: 1888.
Backfilling of the pit shall be carried out as per the directions of the Owner. Unless
otherwise specified the excavated soil shall be used for this purpose. In cases of gravelboulder or rocky strata, respective relevant codes shall be followed for tests.
2.6 Water Sample
Representative samples of ground water shall be taken when ground water is first
encountered before the addition of water to aid drilling of boreholes. The samples shall be
of sufficient quantity for chemical analysis to be carried out and shall be stored in airtight
containers.
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Technical Specification
2.7 Back Filling Bore Holes
On completion of each hole, the Contractor shall backfill all boreholes as directed by the
Owner. The backfill material can be the excavated material.
2.8 laboratory Test
The laboratory tests shall be carried out progressively during the field work after sufficient
number of samples have reached the laboratory in order that the test results of the initial
boreholes can be made use of in planning the later stages of the field investigation and
quantum of laboratory tests.
All samples brought from field, whether disturbed or undisturbed shall be
extracted/prepared and examined by competent technical personnel, and the test shall be
carried out as per the procedures laid out in the relevant I.S.Codes.
The following laboratory tests shall be carried out:
i) Visual and Engineering Classification.
ii) Liquid limit, plastic limit and shrinkage limit for CΦ soils.
iii) Natural moisture content, bulk density and specific gravity.
iv) Grain size distribution.
v) Swell pressure and free swell index determination.
vi) California bearing ratio.
vii)
Consolidated un-drained test with pore pressure measurement.
viii) Chemical tests on soil and water to determine the carbonates, sulphates, nitrates,
chlorides, Ph value, and organic matter and any other chemicals harms to the
concrete foundation.
ix) Rock quality designation (ROD), RMR in case of rock is encountered.
2.9 Test Results and Reports
1.
The Contractor shall submit the detailed report in two (2) copies wherein information
regarding the geological detail of the site, summarized observations and test data, bore
logs, and conclusions and recommendations on the type of foundations with supporting
calculations for the recommendations. Initially the report shall be submitted by the
Contractor in draft form and after the draft report is approved, the final report in four (4)
copies shall be submitted. The test data shall bear the signatures of the Investigation
Agency, Vendor and also site representative of POWERGRID.
2.
The report showing the locations of the exploration work i.e., bore holes, dynamic cone
penetration tests, trial pits. Plate load test, etc.
a) A plan showing the locations of the exploration work i.e., bore holes, dynamic cone
penetration tests, trial pits. Plate load test, etc.
b) Bore Logs: Bore logs of each bore holes clearly identifying the stratification and the type of
soil stratum with depth. The values of Standard Penetration Test (SPT) at the depths where
the tests were conducted on the samples collected at various depths shall be clearly shown
against that particular stratum.
Test results of field and laboratory tests shall be summarized strata wise as well in
combined tabular form. All relevant graphs, charts tables, diagrams and photographs, if
any, shall be submitted along with report. Sample illustrative reference calculations for
settlement, bearing capacity, pile capacity shall be enclosed.
3.0 Recommendations
The report should contain specific recommendations for the type of foundation for the
various structures envisaged at site. The Contractor shall acquaint himself about the type
of structures and their functions from the Owner. The observations and recommendations
shall include but .not limited to the following:
a) Geological formation of the area, past observations or historical data, if available,
for the area and for the structures in the nearby area, fluctuations of water table,
etc. slope stability characteristics and landslide history of the area shall be
specifically highlighted. Remedial measures to be adopted shall also be given.
b) Recommended type of foundations for various structures. If piles are
recommended the type, size and capacity of pile and groups of piles shall be
given after comparing different types and sizes of piles and pile groups.
c) Allowable bearing pressure on the soil at various depths for different sizes of
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Technical Specification
the foundations based on shear strength and settlement characteristics of soil
with supporting calculations. Minimum factor of safety for calculating net safe
bearing capacity shall be taken as 3.0 (three). Recommendation of liquifaction
characteristics of soil shall be provided.
d)
Recommendations regarding slope of excavations and dewatering
schemes, if required. Required protection measures for slope stability for
cut and fill slopes of switchyard and approach road with stone
pitching/retaining walls shall be clearly spelt out. Calculation shall also
be provided for stability adequacy.
e)
Comments on the Chemical nature of soil and ground water with due
regard to deleterious effect of the same on concrete and steel and
recommendations for protective measures.
f)
If expensive soil is met with, recommendation on removal or
retainment of the same under the structure, road, drains, etc.,
shall be given. In the later case detailed specification of any
special treatment required including specification or materials to
be used, construction method, equipments to be deployed, etc.,
shall be furnished. Illustrative diagram of a symbolic foundation
showing details shall be furnished.
g) Recommendations for additional investigations beyond the scope of
the present work, if considered such investigation as necessary.
4.0
SITE PREPARATION
The Contractor shall be responsible for proper leveling of switchyard site as per layout and
levels of switchyard finalized during detailed engineering stage. The Contractor at his own
cost shall make the layout and levels of all structure, etc., from the general grids of the plot
and benchmarks set by the Contractor and approved by the Owner. The Contractor shall
give all help in instruments, materials and personal to the Owner for checking the detailed
layout and shall be solely responsible for the correctness of the layout and levels. Site
leveling shall be in the scope of the contractor. Bidder may decide the level of the sites.
However, the level shall be such that it is 300 mm higher than the highest flood level (HFL)
of the site.
5.0
SCOPE OF WORKS
This clause covers the design and execution of the work for site preparation, such as
clearing of the site, the supply and compaction of fill material, slope protection by stone
pitching/retaining walls depending on the site location/ condition, excavation and
compaction of backfill for foundation, road construction, drainage, trenches and final
topping by stone (broken hard stone).
5.1
General
1) The Contractor shall develop the site area to meet the requirement of the intended
purpose. The site preparation shall conform to the requirements of relevant sections
of this specification or as per stipulations of standard specifications. Necessary
protection of slope of switchyard area and approach road shall also be carried out
by contractor.
2) If fill material is required, the fill material shall be suitable for the above
requirement. The fill shall be such a material and the site so designed as to
prevent the erosion by wind and water of material from its final compacted
position or the in-site position of undisturbed soil.
3) When embankments are to be constructed on slopes of 15% or greater, benches or
steps with horizontal and vertical faces shall be cut in the original slope prior to
placement of embankment material. Vertical faces shall measure not more than 1 m in
height.
4) Embankments adjacent to abutments, culverts, retaining walls and similar structures shall
be constructed by compacting the material in successive uniform horizontal layers not
exceeding 15 cm in thickness. (Of loose material before compaction). Each layer shall be
compacted as required by means of mechanical tampers approved by the Owner. Rocks
larger than 10 cm in any direction shall not be placed in embankment adjacent to
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Technical Specification
structures.
5) Earth embankments of roadways and site areas adjacent to buildings shall be placed in
successive uniform horizontal layers not exceeding 20 cm in thickness in loose stage
measurement and compacted to the full width specified. The upper surface of the
.embankment shall be shaped so as to provide complete drainage of surface water at all
times.
6) The pitching shall be designed and provided for slope protection as per approved
drawings. The stone used shall be sound, hard, durable and fairly regular in shape.
Stones subjected to marked deterioration by water or weather shall not be used. Suitable
measures shall be provided to prevent erosion by seepage of water. Largest stone
procurable shall be used as approved by owner for the work. Random rubble masonry
(1:6) retaining walls shall be provided wherever required as per site condition.
5.2 Compaction
1. The density to which fill materials shall be compacted shall be as per relevant IS and as
per direction of Owner. All compacted sand filling shall be confined as far as practicable.
Backfilled earth shall be compacted to minimum 95% of the Standard Proctor's density at
OMC. The sub-grade for the roads and embankment filling shall be compacted to 70%
relative density (minimum).
2. At all times unfinished construction shall have adequate drainage. Upon completion of
the road's surface course, adjacent shoulders shall be given a final shaping, true
alignment and grade.
3. Each layer of earth embankment when compacted shall be as close to optimum moisture
content as practicable. Embankment material, which does not contain sufficient moisture
to obtain proper compaction, shall be wetted. If the material contains any excess
moisture then it shall be allowed to dry before rolling. The rolling shall begin at the edges
overlapping half the width of the roller each time and progress to the center of the road or
towards the building as applicable. Rolling will also be required on rock fills. No
compaction shall be carried out in rainy weather.
5.3
Requirement for fill material under foundation
The thickness of fill material under the foundations shall be such that the maximum
pressure from the footing, transferred through the fill material and distributed onto the
original undisturbed soil will not exceed the allowable soil bearing pressure of the original
undisturbed soil. For expansive soils the fill materials and other protections, etc., to be
used under the foundation is to be got approved by the Owner.
6.0
6.1
ANTI-WEED TREATMENT AND STONE SPREADING
Scope of Works
The Contractor shall furnish all labour, equipment and materials required for complete
performance of the work in accordance with the drawings specification and direction of the
Owner.
Stone spreading shall be done in the areas of the switchyard wherever equipments and or
structures are to be provided under present scope of work. The stone spreading in future
areas shall also be provided in case potential without stone layer is not well within safer
limits.
7.0
GENERAL REQUIREMENT
7.1 The material required for site surfacing/stone filling shall be free from all types of organic
materials and shall be of standard quality, and as approved by the Owner.
The material to be used for stone filling/site surfacing shall be uncrushed/ crushed/broken
stone of 20 mm nominal size (upgraded single size) conforming to Table 2 of IS:383-1970.
Hardness, Flakiness shall be as required for wearing courses are given below:
a) Sieve Analysis Limits (Gradation)
(IS: 383 - Table 2)
Sieve Size
% passing by weight
40mm
100
20 mm
85 - 100
10 mm
0-20
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Technical Specification
4.75 mm
0-5
b) Hardness
Abrasion value (IS: 2386 Part-IV) - not more than 40%
Impact value (IS: 2386 Part-IV) - not more than 30% and frequency shall be one test per
500 cum with a minimum of one test per source,
c) Flakiness Index
One test shall be conducted per 500 cum of aggregate as per IS: 2386 Part-I and
maximum value is 25%,
7.2 After all the structures/equipments are erected and anti-weed treatment is complete, the
surface of the switchyard area shall be maintained, rolled/ compacted to the lines and
grades as decided by Engineer-in-Charge. Deweeding including removal of roots shall be
done before rolling is commenced, Engineer-in-Charge shall decide final formation level so
as to ensure that the site appears uniform devoid of undulations, The final formation level
shall however be very close to the formation level indicated in the drawing using half ton
roller with suitable water sprinkling arrangement to form a smooth and compact surface.
7.3 A base layer of uncrushed/crushed/broken stone of 20 mm nominal size (ungraded single
size) shall be spread and rolled/compacted by using half ton roller with 4 to 5 passes and
water sprinkling to form a minimum 50 mm layer on the finished ground level of the
specified switchyard area excluding roads, drains, cable trench and tower and equipment
foundations as indicated in the drawing.
7.4 Over the base layer of site surfacing material, a final surface course of minimum 50 mm
thickness of 20 mm nominal size (single size ungraded) broken stone as specified above
shall be spread and compacted by light roller using half tones steel roller (width 30" and
24" diameter) with water sprinkling as directed by he Engineer-in-Charge. The water shall
be sprinkled in such a way that bulking does not take place.
7.5 In areas that are considered by the Engineer-in-Charge to be too congested with
foundations and structures for proper rolling of the site surfacing material by normal rolling
equipments, the material shall be compacted by hand, if necessary. Due care shall be
exercised so as not to damage any foundation structures or equipment during rolling
compaction.
7.6 Before taking up stone filling, anti-weed treatment shall be applied in the switchyard area
wherever gravel filling is to be done, and the area shall be thoroughly de-weeded including
removal of roots. The recommendation of local agriculture or horticulture department shall
be sought wherever feasible while choosing the type of chemical to be used. Nevertheless
the effectiveness of the chemical shall be demonstrated by the Contractor in a test area of
10M x 10M (approx.) and monitored over a period of two to three weeks by the Engineerin-Charge. The final approval shall be given by Engineer-in-Charge and final approval
given based on the results.
7.7
The anti-weed chemical shall be procured from reputed manufacturers.
The dosage and application of chemical shall be strictly followed as per manufacturer's
recommendation. The contractor shall be required to maintain the area free of weeds for a
period of 1 year from the date of application of 1st dose of anti-weed chemicals.
8.0
SITE DRAINAGE
1. Adequate site drainage system shall be provided by the Contractor. The Contractor shall
obtain rainfall data and design the storm water drainage system, (culverts, ditches, drains,
etc.) to accommodate run off due to the most intense rainfall that is likely to occur over the
catchment area in one hour period on an average of once in tem years. The surface of the
site shall be sloped to prevent the ponding of water.
2. The maximum velocity for pipe drains and open drains shall be limited to 2.4m/sec and
1.8m/sec respectively. However, minimum non-slitting velocity of 0.6 m/sec shall be
ensured. Longitudinal bed slope not milder than 1 in 1000 shall be provided.
3. For design of RCC pipes for drains and culverts, 18:456 and 18:783 shall be followed.
4. The Contractor shall ensure that water drains are away from the site area and shall
prevent damage to adjacent property by this water. Adequate protection shall be given to
site surfaces, roads, ditches, culverts, etc., to prevent erosion of material by water.
5. The drainage system shall be adequate without the use of cable/pipe trenches. (Pipe
drains shall be provided in areas of switchyard where movement of crane will be
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Technical Specification
necessary in operating phase of the substation).
Open surface drains shall be provided with the Cement Concrete 1:2:4 of minimum
thickness of 100 mm or more as per design condition.
7. Pipe drains shall be connected through manholes at an interval of max. 30m. Effluents
shall be suitably treated by the Contractor to meet all the prevalent statutory requirements
and local pollution control norms and treated effluents shall be conveyed to the storm
water drainage system at a suitable location for its final disposal.
8. Invert of the drainage system shall be decided in such a way that the water can easily be
discharged above the High Flood Level (HFL) outside substation boundary at suitable
location upto a maximum 50M beyond boundary wall ot substation or actual whichever
occurs earlier and approved by Owner. Pumps for drainage of water (it required) shall be
provided by Contractor.
9. All internal site drainage system, including the final connection/disposal to owner
acceptance points shall be pat of Supplier's scope including all required civil work,
mechanical and electrical systems. The Contractor shall connect his drain(s) at one or
more points to outfall points as feasible at site.
10. The drainage scheme and associated drawings shall be got approved.
6.
9.0
ROADS AND CULVERTS
1. The main approach road including modification of existing road to meet the site conditions,
roads for access to equipment and building within substation are in the scope of bidder.
Layout of the roads shall be based on General detail and Arrangement drawing for the
substation.
2. All substation roads be constructed so as to permit transportation of all heavy equipment.
The roads shall have min.3.75 black topping. Moorum shoulder shall be provided on either
side of the road. The width of the shoulder shall be as per approved drawing depending
upon the site conditions.
3. Road construction shall be as per IRC standards.
4. Adequate provision shall be made for road drainage. Protection of cut and embankment
slopes of roads as per slope stability requirement shall be made.
5. All the culverts and its allied structure (required for road/rail, drain trench crossings, etc.)
shall be designed for Class-AA loading as per IRC standards code and should be checked
for loading.
6. All roads shall be designed for Class-'E' of traffic as per IRC-37 Guidelines for the design
of flexible pavements.
10.0
TRANSFORMER FOUNDATION
The Contractor shall provide a road system integrated with the transformer foundation to
enable installation and the replacement of any failed unit by the spare unit located at the
site. This system shall enable the removal of any failed unit from its foundation to the
nearest road. If trench/drain crossings are required the suitable R.C.C. culverts shall be
provided in accordance with I.R.C. Code & relevant IS.
11.0
FIRE PROTECTION WALLS
11.1 General
Fire protection walls shall be provided in accordance with Tariff Advisory Committee (TAC)
recommendations.
11.2 Application Criteria
A firewall shall be erected between the transformer to protect each one from the effects of
fire on another as per TAC guidelines.
Also, if the free distance between the transformer and auxiliary services transformer is
less.
11.3 Fire resistance
The firewall shall have a minimum fire resistance of 3 hours. The partitions, which are
made to reduce the noise level, shall have the same fire resistance where the partitions
are also used as firewalls. The walls of the building, which are used as firewalls, shall also
have a minimum fire resistance of 3 hours.
The firewall shall be designed in order to protect against the effect of radiant heat and
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Technical Specification
flying debris from an adjacent fire.
11.4 Mechanical resistance
The firewall shall have the mechanical resistance to withstand local atmospheric
conditions. If this wall shall serve as a support for equipment such as insulators, etc., its
mechanical rigidity must be increased. Connecting the walls by steel or other structures,
which may produce a reversing torque if overheated, shall be avoided.
11.5 Dimensions
The firewall shall extend at least 2 m on each side of the transformer and at least 1 m
above the conservator tank or safety vent.
These dimensions might be reduced in special cases, and if T AC permits so, where there
is lack of space. A minimum of 2 meter clearance shall be provided between the
equipments e.g., transformer and fire walls.
The building walls, which act as firewalls, shall extend at least 1 m above the roof in order
to protect it.
11.6 Materials
The firewall may be made of reinforced concrete (M-20 grade), as per the system
requirements. Materials used must conform to the standards of the National Fire
Prevention Association and T AC norms.
12.0
CABLE AND PIPE TRENCHES
1. The cable trenches and precast removable RCC cover (with lifting arrangement)
2. The cable trench wall shall be designed for the following loads.
i) Dead load of 155 Kg/m length of cable support + 75 Kg on one tier at the end.
ii) Triangular earth pressure + uniform surcharge pressure of 2 T/m2.
3. Cable trench covers shall be designed for self-weight of top slab + UDL of 2000 Kg/ m2 +
concentrated load of 200 Kg at centre of span on each panel.
4. Cable trench crossing the road/rails shall be designed for class AA. Loading of
IRC/relevant IS Code and should be checked for transformer loading.
5. Trenches shall be drained. Necessary sumps be constructed and sump pumps if
necessary shall be supplied. Cable trenches shall not be used as storm water drains.
6. The top of trenches shall be kept at least 100 mm above the finished ground level. The
top of cable trench shall be such that the surface rainwater does not enter the trench.
7. All metal parts inside the trench shall be connected to the earthing system.
8. Cables from trench to equipments shall run in hard conduit pipes.
9. Trench wall shall not foul with the foundation. Suitable clear gap shall be provided.
10. The trench bed shall have a slope of 1/500 along the run and 1/250 perpendicular to the
run.
11. All the construction joints of cable trenches i.e., between base slab to base slab and the
junction of vertical wall to base slab as well as from vertical wall to wall and all the
expansion joints shall be provided with approved quality PVC water stops of approx. 230
x 5 mm size for those sections where the ground water table is expected to rise above
the junction of base slab and vertical wall of cable trenches.
12. Cable trenches shall be blocked at the ends if required with brick masonry in cement
sand mortar 1:6 and plaster with 12 mm thick 1:6 cement sand mortar.
13. Cable trenches shall be provided with suitable hangers to support the running cables.
13.0 FOUNDATION I RCC CONSTRUCTION
13.1 General
1. Work covered under this Clause of the Specification comprises the design and
construction of foundations and other RCC constructions for switchyard structures,
equipment supports, trenches, drains, jacking pad, control cubicles, bus supports,
transformer, marshalling kiosks, auxiliary equipments and systems, buildings, tanks,
boundary wall or for any other equipment or service and any other foundation required to
complete the work. This clause is as well applicable to the other ECC constructions.
2. Concrete shall conform to the requirements mentioned in IS: 456 and all the tests shall
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Technical Specification
be conducted as per relevant Indian Standard Codes as mentioned in Standard field
quality plan appended with the specification.
A minimum grade of M20 concrete (1:5:3 mix) shall be used for all structural/load bearing
members as per latest IS 456.
3. If the site is sloppy, the foundation height will be adjusted to maintain the exact level of
the top of structures to compensate such slopes.
4. The switchyard foundation's plinths and building plinths shall be minimum 300 mm and
500 mm above finished ground level respectively.
5. Minimum 75 mm thick lean concrete (1:4:8) shall be provided below all underground
structures, foundations, trenches, etc., to provide a base for construction.
6. Concrete made with Portland slag cement shall be carefully cured and special
importance shall be given during the placing of concrete and removal of shuttering.
7. The design and detailing of foundations shall be done based on the approved soil data
and sub-soil conditions as well as for all possible critical loads and the combinations
thereof. The Spread footings foundation or pile foundation as may be required based on
soil/sub-soil conditions and superimposed loads shall be provided.
8. If pile foundations are adopted, the same shall be case-in-situ driven/bored or precast or
under-reamed type as per relevant parts of IS Code 2911. Only RCC piles shall be
provided. Suitability of the adopted pile foundations shall be justified by way of full design
calculations. Detailed design calculations shall be submitted by the bidder showing
complete details of piles/pile groups proposed to be used. Necessary initial load test shall
also be carried out by the 'bidder at their cost to establish the piles design capacity. Only
after the design capacity of piles has been established, the Contractor shall take up the
job of piling. Routine tests fro the piles shall also be conducted. All the work (design &
testing) shall be planned in such a way that these shall not cause any delay in project
completion.
13.2 Design
All foundation shall be of reinforced cement concrete. The design and construction of RCC
structures shall be carried out as per IS: 456 and minimum grade of concrete shall be M20. Higher grade of concrete than specified above may be used at the discretion of
Contractor without any additional financial implication to the Owner.
Limit state method of design shall be adopted unless specified otherwise in the
specification.
For detailing of reinforcement IS: 2502 and SP: 34 shall be followed. Cold twisted
deformed bars (Fe=415 N/mm2) conforming to IS: 1786 shall be used as reinforcement.
However, in specific areas, mild steel (Grade-I) conforming to IS: 432 can also be used.
Two layers of reinforcement (on inner and outer face) shall be provided for wall and slab
sections having thickness of 150 mm and above. Clear cover to reinforcement towards the
earth face shall be minimum 40 mm.
RCC water retaining structures like storage tanks, etc., shall be designed as uncracked
section in accordance with IS: 3370 (Part I to IV) by working stress method. However,
water channels shall be designed as cracked section with limited steel stresses as per IS:
3370 (Part I to IV) by working stress method.
The procedure used for the design of the foundations shall be the most critical loading
combination of the steel structure and or equipment and or superstructure and other
conditions, which produces the maximum stresses in the foundation or the foundation
component and as per the relevant IS Codes of foundation design. Detailed design
calculations shall be submitted by the bidder showing complete details of piles/pile groups
proposed to be used.
Design shall consider any sub-soil water pressure that may be encountered following
relevant standard strictly.
Necessary protection to the foundation work, if required shall be provided to take care of
any special requirements for aggressive alkaline soil, black cotton soil or any other type of
soil which is detrimental/harmful to the concrete foundations.
RCC columns shall be provided with rigid connection at the base.
All sub-structures shall be checked for sliding and overturning stability during both
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Technical Specification
construction and operating conditions for various combinations of loads. Factors of safety
for these cases shall be taken as mentioned in relevant IS Codes or as stipulated
elsewhere in the Specifications. For checking against overturning, weight of soil vertically
above footing shall be taken and inverted frustum of pyramid of earth on the foundation
should not be considered. E
Earth pressure for all underground structures shall be calculated using coefficient of earth
pressure at rest, co-efficient of active or passive earth pressure (whichever is applicable).
However, for the design of substructures of any underground enclosures, earth pressure at
rest shall be considered.
ln addition to earth pressure and ground water pressure etc., a surcharge load of 2T/Sq.m
shall also be considered for the design of all underground structures including channels,
sumps, tanks, trenches, sub-structure of any underground hollow enclosure, etc., for the
vehicular traffic in the vicinity of the structure.
Following conditions shall be considered for the design of water tank in pumps house,
channels, sumps, trenches and other underground structures:
a) Full water pressure from inside and no earth pressure and ground water pressure and
surcharge pressure from outside (application only to structures, which are liable to be
filled up with water or any other liquid).
b) Full earth pressure, surcharge pressure and ground water pressure from outside and
no water pressure from inside.
c) Design shall also be checked against buoyancy due to the ground water during
construction and maintenance stages. Minimum factor of safety of 1.5 against
buoyancy shall be ensured ignoring the superimposed loadings.
The foundations shall be proportioned so that the estimated total and differential
movements of the foundations are not greater than the movements that the structure or
equipment is designed to accommodate.
The foundations of transformer and circuit breaker shall be of block type foundation.
Minimum reinforcement shall be governed by IS: 2974 and IS: 456.
The tower and equipment foundations shall be checked for a factor of safety of 2.2 for
normal condition and 1.65 for short circuit condition against sliding, overturning and
pullout. The same factors shall be used as partial safety factor overloads in limit st 1te
design also.
13.3 Admixtures & Additives
Only approved admixtures shall be used in the concrete for the Works. When more than
one admixture is to be used, each admixture shall be batched in its own, batch and added
to the mixing water separately before discharging into the mixer. Admixtures shall be
delivered in suitably labeled containers to enable identification.
Admixtures in concrete shall conform to IS: 9103. The water proofing cement additives
shall conform to IS: 2645. Owner shall approve concrete Admixtures/Additives.
The Contractor may propose and the Owner may approve the use of a water-reducing setretarding admixture in some of the concrete. The use of such an admixture will not be
approved to overcome problems associated with inadequate concrete plant capacity or
improperly planned placing operations and shall only be approved as an aid to overcoming
unusual circumstances and placing conditions.
The water reducing set-retarding admixture shall be an approved brand of Lignosulphonate type admixture.
The water proofing cement additives shall be used as required/advised by the owner.
14.0 GATES AND BOUNDARY WALL
The Gate frame shall be made of medium duty MS pipe conforming to relevant IS with
welded joints.
The gates shall be fabricated with welded joints to achieve rigid connections. The gate
frames shall be painted with one coat of approved steel primmer and two coats of
synthetic enamel paint.
Gates shall be fitted with approved quality iron hinges, latch and latch catch. Latch and
latch catch shall be suitable for attachment and operation of pad lock from either side of
gates. Hinges shall permit gates to swing through 180 degree back against fence.
Gates shall be fitted with galvanized chain hook or gate hold back to hold gates open.
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Technical Specification
Double gates shall be fitted with centre rest and drop bolt to secure gates in closed
position.
Gates shall be installed in locations shown on drawings. Next to the main gate, a men gate
(1.25 m wide, single leaf) shall also be provided.
Bottom of gates shall be set approximately 40 mm above ground surface and necessary
guiding mechanism shall be fitted.
The Contractor shall design and& construct boundary wall around substation area as per
requirements. The boundary wall shall be of height 3.0M and shall be made of RCC frame
construction with RCC column and plinth beam arrangement and panels filled with one
brick thick wall in cement sand mortar 1 :6. The boundary wall shall be plastered on both
external and internal faces with cement and sand plaster 1:6 of thickness18 mm and 12
mm respectively. An additional barbed Y -shaped arm of M8 angle 50x50x6 with 3-rows (6
nos) barbed wire A-4 18:278. Expansion joints shall be provided as per codal
requirements. M8 grating shall be provided at required locations for drainage purposes.
The boundary wall shall be painted with minimum two coats of color wash over a base
coat of white wash with line. The front portion of boundary wall shall however be with a RC
jail and 12 mm square MS bar top above brick work and pebble dash plaster finish with
colour pigment. The steel work shall be given two coats of synthetic enamel paint of
approved make over one coat of primer. A tentative drawing is enclosed for guidance
purpose.
A Security room shall be provided at the entrance of switchyard. The minimum dimension
of the room shall be 3.0 m length and 3.0 m width. The roof shall be at RCC and
aesthetically pleasing.
15.0 BUILDINGS - GENERAL REQUIREMENTS
15.1
General
The scope include the design, engineering and construction including anti-termite
treatment, plinth protection, DPC of Building including sanitary, water supply,
electrification, false ceiling etc., of control room building, and DG set building. The
buildings shall be of RCC framed structure of concrete of M20 grade (Min.)
15.2 Control Room Building
Minimum floor area requirements shall be 120 Sq. Meter which may be increased at the
time of detailed engineering to suit project requirements. The layout of the control room
shall be finalized as per detailed engineering to suit project requirements.
An open space of 1 m minimum shall be provided on the periphery of the rows of panel
and equipment generally in order to allow easy operator movement and access as well as
maintenance.
Any future possibility of annexed building shall be taken care of while finalizing the layout
of the control room building.
Minimum head room of 3 M below soffit of beams/false ceiling shall be considered for
rooms. The roof shall have four side sloping roof or flat roof as finalized during detailed
engineering.
15.2.1 Design
The buildings shall be designed:
i. To the requirements of the National Building Code of India, and the standards quoted
therein.
ii. For the specified climatic and loading conditions
iii. To adequately suit the requirements of the equipment and apparatus contained in the
buildings and in all respects to be compatible with the intended use and occupancy
iv. With a functional and economical space arrangement.
v. For a life expectancy of structure, systems and components not less than that of the
equipment, which is contained in the building, provided regular maintenance is carried
out
vi. Be aesthetically pleasing. Different buildings shall show a uniformity and consistency in
architectural design.
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Technical Specification
vii. To allow for easy access to equipment and maintenance of the equipment.
viii. With, wherever required, fire retarding materials for walls, ceilings and doors, which
would prevent supporting or spreading of fire.
ix. With materials preventing dust accumulation.
b) Suitable expansion joints shall be provided in the longitudinal direction wherever
necessary with provision of twin columns.
c) Individual members of the buildings frame shall be designed for the worst combination of
forces such as bending moment, axial force, shear force, torsion, etc.
d) Permissible stresses for different load combinations shall be taken as per relevant IS
Codes.
e) All cable vaults shall be located above ground levels i.e., cable vaults shall not be
provided as basements in the buildings.
f) The building lighting shall be designed in accordance with the requirements.
g) One emergency exit shall be provided in control room building.
15.2.2 Design loads
Building structures shall be designed for the most critical combinations of dead loads,
super-imposed loads, equipment loads, crane load, wind loads, seismic loads, and
temperature loads.
Dead loads shall include the weight of structures complete with finishes, fixtures and
partitions and should be taken as per IS: 1911.
Super-imposed loads in different areas shall include live loads, minor equipment loads,
cable trays, small pipe racks/hangers and erection, operation and maintenance loads.
Equipment loads shall constitute, if applicable, all load of equipments to be supported on
the building frame.
For crane loads an impact factor of 30% and lateral crane surge of 10% (lifted weight +
trolley) shall be considered in the analysis of frame according to provisions of IS: 875.the
horizontal surge shall be 5% of the static wheel load.
The wind loads shall be computed as per IS 875, Seismic Coefficient method shall be
used for the seismic analysis as per IS 1893 with importance factor 1.5.
For temperature loading, the total temperature variation shall be considered as 2/3 of the
average maximum annual variation in temperature. The average maximum annual
variation in temperature for the purpose shall be taken as the difference between the mean
of the daily minimum temperature during the coldest month of the year and mean of daily
maximum temperature during the hottest month of the year. The structure shall be
designed to withstand stresses due to 50% of the total temperature variation.
Wind and Seismic forces shall not be considered shall not be considered to act
simultaneously.
Floors/slabs shall be designed to carry loads imposed by equipment, cables piping travel
of maintenance trucks and equipment and other loads associated with building. Floors
shall be designed for live loads as per relevant IS. Cable and piping loads shall also be
considered additionally for floors where these loads are expected.
In addition, beams shall be designed for any incidental point loads to be applied at any
point along the beams. The floor loads shall be subject to Owner's approval.
For consideration of loads on structures, IS: 875, the following minimum superimposed live
loads shall, however, be considered for the design.
a) Roof
1.5 KN/M2
For accessible roofs
0.75 KN./M2
For in- accessible roofs
b) RCC- Floor
i) 5 KN/M2
For offices
2
ii) 10 KN/M
For equipment floors or
( Minimum)
actual requirement, if higher than
10 KN/M2, based on equipment
component weight and layout plans
c) Toiler Room
2 KN/M2
d) Chequered plate floor
4 KN/M2
e) Walkways
3 KN/M2
Any additional load coming in the structure shall be calculated as per IS: 875.
15.2.3 Submission
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Technical Specification
The following information shall be submitted for review and approval to the Owner:
Design criteria shall comprise the codes and standards used, applicable climatic data
including wind loads, earthquake factors maximum and minimum temperatures applicable
to the building locations, assumptions of dead and live loads, including equipment loads,
impact factors, safety factors and other relevant information.
Structural design calculations and drawing (including constructions / fabrication) for all
reinforced concrete and structural steel structures.
Fully, dimensioned concept plan including floor plans, cross-sections, longitudinal
sections, elevations and perspective view of each building. These drawings shall be drawn
at a scale not smaller than 1 :50 and shall identify the major building components.
Fully dimensioned drawings showing details and sections drawn to scales of sufficient size
to clearly show sizes and configuration of the building components and the relationship
between them.
Product information of building components and materials, including walls partitions
flooring ceiling, roofing, door and windows and building finishes.
A detailed schedule of building finishes including colour schemes.
A door and window schedule showing door types and locations, door lock sets and latch
and other door hardware.
Approval of the above information shall be obtained before ordering materials or starting
fabrication or construction as applicable.
15.2.4 Finish Schedule
The finishing schedule is given in subsequent clauses.
15.2.5 Flooring
Flooring in various rooms of control room building shall be as for detailed schedules given
in Table-1. High Voltage insulating mat conforming to IS 15652:2006 are to be provided in
front of Indoor Switchgear Control panels inside the Control Room.
15.2.6 Walls
Control room buildings shall be of framed superstructure. All walls shall be non-load
bearing walls. Min. thickness of external walls shall be 230 mm (One brick) with 1:6
cement sand mortar.
15.2.7 Plastering
All internal walls shall have minimum 15 mm thick 1:6 cement sand plaster. The ceiling
shall have 6mm thick 1:4 cement sand plaster.
15.2.8 Finishing
All external surfaces shall have 18 mm cement plaster in two coats, under layer 12 mm
thick cement plaster 1:5 and finished with a top layer 6 mm thick cement plaster 1:6 (DSR
(13.19) with water proofing compound. The paint shall be anti-fungal quality of reputed
brand suitable for masonry surfaces for high rainfall zone. White cement primer shall be
used as per manufacturer's recommendation.
INTERNAL FINISH SCHEDULE IS GIVEN TABLE - 1
SI
Location
No.
1.
Control Room
&
Relay room
Flooring &
Skirting
150 mm High
Homogeneous
PVC /Vetrified
tiles 2 mm
thick
over 25 mm
thick
1 :2:4 under
bed
neat cement
Wall Internal
Ceiling
Plastic 7.3 mm False
thick
Ceiling
ceramic tiles
&
(DSR
Under deck
11.41 A.2.1)
insulation
Doors, Windows Ventilators
Anodised aluminium Jindal
or
equivalent extruded
sections as
per IS 733 & 1285 Glazing
Flat
(DSR 97-11.64.2 drawn
sheet &
11.4.1) glass (Min 5.5 mm
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Technical Specification
finished
flooring
2.
Sub-Station incharge,
officers,
corridor, staff,
rooms
3.
Battery room
4.
Cable vault
double sheet
(if
required)
5.
Toilet
6.
Other
areas
not
specified
Oil bound
plastic paint
washable
distemper on
smooth
surface
applied with
POP
putty
Smooth
surface
(DSR-97)
applied with
(11.48.1)
POP
putty.
DADO acid
resistant title
2.1 M
high Acid
resistant
paint above
Acid Resistant
2.1 M
Tiles
high acid
25 mm thick
resistant
(DSR
paint above
9711.36 C 12)
2.1 m
upto ceiling
(DSR
97.11.36 C
2.2) &
13.96.1)
Oil bound
IPS flooring
distemper
(DSR 97
White wash
11.4.3)
(DSR 97
13.72.1)
DADO glazed
tile
Non-solid/
2.1 M high for
vetrified
toilet for pantry
Terrazzo tiles
above working
with
platform upto
White cement
750
(DSR97,11.29
mm
a.1)
(DSR 97
11.36B)
Vetrified
Plastic/O.B.
Terrazzo tiles
distemper Dry
with
distemper
white cement
(DSR
(DSR 97 29
97.13.75)
A.1)
Vetrified
Terrazzo tiles
with
white cement
(DSR97) (11.29
A.1)
thick)
double glazing with 12 mm
gap
hermetically sealed.
(DSR097,
24.1, 24.3, 24.4
False
ceiling
&
under deck
insulation
Teak wood frame flush
doors
shutter (DSR 97 9.1.3 &
9.4 A.2.2)
Windows, Ventilators
Aluminium
as at 1.
For entrance with glazing
Steel door 45 mm thick
double
Acid
sheet 18 G steel suitably
resista
reinforced and filled with
nt
mineral
paint (DSR
wool. Hot rolled steel
97
framed
1372.1)
glazed window and
ventilators.
White
wash
Steel door double sheet as
above.
Ventilators as at 5.
White
wash
Weather
coat
Teak wood frame flush
door
shutter with anodized
Aluminium
fixtures best quality
(DSR 97 9.1.3 & 9.4 a 2)
Windows, ventilators
aluminium as at 1.
White wash
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Technical Specification
Note : DSR item references to be read with CPWD specifications are only for material and
workmanship guidance of the Contractor.
15.2.9 Roof
Roof of the CR. Building shall consist of Cast-in-situ RCC slab treated with a water
proofing system which shall be an integral cement based treatment conforming to CPWD
specification (item NO.25.8 of DSR 1997) the water proofing treatment shall be of following
operations.
a) Applying and grouting a slurry coat of neat cement using 2.75 kg/m2 of cement
admixed with proprietary water proofing compounds conforming to IS:2645 over the
RCC slab including cleaning the surface before treatment.
b) Laying cement concrete using broken bricks/bricks brick bats 25 mm to 100 mm size
with 505 of cement mortar 1:5 (1 cement: 5 coarse sand) admixed with proprietary
water proofing compound conforming to IS: 2645 over 20 mm thick layer of cement
mortar of min 1:5 (Cement: 5 coarse sand) admixed with proprietary water proofing
compound conforming to IS:2645 to required slope and treating similarly the adjoining
walls upto 300 mm height including rounding of junctions of walls and slabs.
c) After two days of proper curing applying a second coat of cement slurry admixed with
proprietary water proofing compound conforming to IS:2645.
d) Finishing the surface with 20 mm thick joint less cement mortar of mix 1:4 (1 cement:
4 course sand) admixed with proprietary water proofing compound conforming to
IS:2645 and finally finishing the surface with trowel with neat cement slurry and
making of 300 x 300 mm square.
e) The whole terrace so finished shall be flooded with water for a minimum period of two
weeks for curing and for final test. All above operations to be done in order and as
directed and specified by the Engineering-in-charge.
With average thickness of 120 mm and minimum thickness at khurra at 65 mm.
15.2.10
Glazing
Minimum thickness of glazing shall be 5.5 mm as per IS:2835 sun film shall be provided
for all window/doors of AC rooms.
15.2.11
Doors and Windows
The details of doors and windows of the control room building shall be as per finish
schedule Table-1 and tender drawing with the relevant IS, code. Rolling steel shutters and
rolling steel grills shall be provided as per layout and requirement of buildings. Paints used
in the work shall be of best quality specified in CPWD specification.
15.2.12
Plumbing & Sanitation
i) All plumbing and sanitation shall be executed to comply with the requirements of the
appropriate bye-laws, rules an regulations of the Local Authority having jurisdiction over
such matters. The Contractor shall arrange for all necessary formalities to be met in
regard to inspection, testing, obtaining approval and giving notices etc.
ii) PVC syntax or equivalent make Roof water tank of adequate capacity depending on the
number of users for 24 hours storage shall be provided. Minimum 2 Nos 500 litres
capacity shall be provided.
iii) Galvanized MS pipe of medium class conforming to IS: 1239 shall be used for internal &
external piping work for potable water supply.
iv) Sand CI pipes with lead joints conforming to IS:1729 shall be used for sanitary works
above ground level.
v) Each toilet shall have the following minimum fittings.
a) WC (Western type) 390 mm high with toilet paper roll holder and all fittings
or
WC (Indian Type) Orissa Pattern (580 x 440 mill) with all fittings. (Both types of WCs
shall be provided at alternate locations)
b) Urinal (430 x 260 x 350 mm size) with all fittings.
c) Wash basin (550 x 400 mm size) with all fittings.
d) Bathroom mirror (600 x 450 x 6 mm thick) hard board backing.
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Technical Specification
e) CP brass towel rail (600 x 20 mm) with CP brass brackets.
f) Soap holder and liquid soap dispenser.
vi) Water cooler for drinking water with adequate water storage facility shall be provided and
located near control room instead of near toilet block.
vii) An Eye & [ace fountain conforming to IS:1052 shall be provided for battery room
viii) 1 No. stainless steel kitchen sink with Drain board (510 x 1040 x 178 mm bowl depth)
for pantry shall be provided.
ix) All fittings, fastener, grating shall be chromium plated.
x) All sanitary fixtures and fittings shall be of approved quality and type manufactured by
well known manufacturers. All items brought to site must bear identification marks of the
type of the manufacturer.
xi) Soil, waste and drain pipes, for underground works shall be stone ware for areas not
subject to traffic load. Heavy-duty cast iron pipes shall be used otherwise.
16.0 SECURITY FENCING
Security fencing shall be provided for 1.5 meter above the ground at the switchyard.
Security fencing shall be provided with barbed wire mesh of 5 rows connected with the
PSCC poles at 2 meters interval.
17.0 MISCELLANEOUS GENERAL REQUIREMENTS
17.1
Dense concrete with controlled water cement ratio as per IS-code shall be used for all
underground concrete structures such as pump-house, tanks, water retaining structures,
cable and pipe trenches etc. for achieving water tightness.
17.2
All joints including construction and expansion joints for the water retaining structures
shall be made water tight by using PVC ribbed water stops with central bulb. However,
kicker type (externally placed) PVC water stops shall be used for the base slab and in
other areas where it is required to facilitate concreting. The minimum thickness of PVC
water stops shall be 5 mm and minimum width shall be 230 mm.
17.3
All steel sections and fabricated structures which are required to be transported on sea
shall be provided with anti corrosive paint to take care of sea worthiness.
17.4
All mild steel parts used in the water retaining structures shall be hot-double dip
galvanized. The minimum coating of the zinc shall be 750 gm/sq. m for galvanized
structures and shall comply with IS:2629 and IS:2633. Galvanizing shall be checked and
tested in accordance with 18:2633.The galvanizing shall be followed by the application of
an etching primer and dipping in black bitumen in accordance with B8:3416.
17.5
A screed concrete layer not less than 100 mm thick and of grade not weaker than M10
conforming to IS:456-1978 shall be provided below all water retaining structures. A sliding
layer of bitumen paper or craft paper shall be provided over the screed layer to destroy the
bond between the screed and the base slab concrete of the water retaining structures.
17.6 Bricks having minimum 75 kg/cm2 compressive strength can only be used for masonry
work. Contractor shall ascertain himself at site regarding the availability of bricks of
minimum 75 kg/cm2 compressive strength before submitting his offer.
17.7
Doors and windows on external walls of the building (other than areas provided, with
insulated metal claddings) shall be provided with RCC sun-shade over the openings with
3000 mm projection on either side of the openings. Projection of sunshade from the wall
shall be minimum 450 mm over window openings and 750 mm over door openings.
17.8
All stairs shall have maximum riser height of 150 mm and a minimum tread width of 300
mm. Minimum width of stairs shall be 1500 mm. Service ladder shall be provided for
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Technical Specification
access to all roofs. RCC fire escape staircase shall be provided in control buildings.
17.9
Angles 50 x 50 x 6 mm (minimum) with lugs shall be provided for edge protection all
round cut outs/openings in floor slab, edges of drains supporting grating covers, edges of
RCC cable/pipe trenches supporting covers, edges of manholes supporting covers,
supporting edges of manhole precast cover and any other place where breakage of
corners of concrete is expected.
17.10 Anti termite chemical treatment shall be given to column pits, wall trenches, foundations
of buildings, filling below the floors etc. as per IS:6313 and other relevant Indian
Standards.
17.11 Hand-railing minimum 900 mm high shall be provided around all floor/roof openings,
projections/balconies, walk ways, platforms, steel stairs etc. All handrails and ladder pipes
shall be 32 mm nominal bore MS pipes (medium class) and shall be galvanized (mediumclass as per IS:277). All rungs for ladder shall also be galvanized as per IS:277 medium
classes.
For RCC stairs, hand railing with 20 mm square MS bars, balustrades with suitable MS
flats shall be provided with black PVC sheathing.
17.12 For all civil works covered under this specification, nominal mix by volume batching as
per CPWD specification is intended. The relationship of grade of concrete and ratio of
ingredients shall be as below:
S.No.
Mix
Cement
Sand
Coarse Aggregate of 20 mm Down
Grade as per IS 383
1.
M 10
1
3
6
2.
M 15
1
2
4
3.
M 20
1
1.5
3
The material specification, workmanship and acceptance criteria shall be as per relevant
clauses of CPWD specification and approved standard Field Quality Plan.
17.13 The details given in tender drawings shall be considered along with details available in
this section of the specification while deciding various components of the building.
17.14 Items/components of buildings not explicitly covered in the specification but required for
completion of the project shall be deemed to be included in the scope.
18.0
INTERFACING
The proper coordination & execution of all interfacing civil works activities like fixing of
conduits in roofs/walls/floors, fixing of foundation bolts, fixing of lighting fixtures, fixing of
supports/embedment, provision of cutouts etc. shall be the sale responsibility of the
Contractor. He shall plan all such activities in advance and execute in such a manner that
interfacing activities do not become bottlenecks and dismantling, breakage etc. is reduced
to minimum.
19.0 WATER SUPPLY
i) Contractor shall make its own arrangement for construction water.
ii) The contractor shall carry out all the plumbing/erection works required for supply of water
in control room building.
iii) The details of tanks, pipes, fittings, fixtures etc for water supply are given elsewhere in
the specification under respective sections.
iv) A scheme shall be prepared by the contractor indicating the layout and details of water
supply which shall be got approved by the Owner before actual start of work including all
other incidental items not shown or specified but as may be required for complete
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Technical Specification
performance of the works.
v) Bore wells with Min 100mm dia casing pipe & 1HP submersible pump to get a discharge
of at least 1000 Litre/Hr. with zealete make iron removed filter to get iron free water.
Water purifier with UV mechanism is to be provided and pumps for water supply are in
the scope of contractor meeting the day-to-day requirement of the water supply.
20.0 SEWERAGE SYSTEM
i) Sewerage system shall be provided for control room building.
ii) The contractor shall construct septic tank and soak pit suitable for 20 users.
iii) The system shall be designed as per relevant IS Codes.
21.0 STATUTORY RULES
21.1
Contactor shall comply with all the applicable statutory rules pertaining to factories act
(as applicable for the State). Fire Safety Rules of Tariff Advisory Committee. Water Act for
pollution control etc.
21.2
Provisions for fire proof doors, no. of staircases, fire separation wall, plastering on
structural members (in fire prone areas) etc. shall be made according to the
recommendations of Tariff Advisory Committee.
21.3
Statutory clearance and norms of State Pollution Control Board shall be followed as per
Water Act for effluent quality from plant.
21.4
Requirement of sulphate resistant cement (SRC) for sub-structural works shall be
decided in accordance with the Indian Standards based on the findings of the detailed soil
investigation to be carried by the bidder.
21.5
Foundation system adopted by the Bidder shall ensure that relative settlement and
other criteria shall be as per provision in IS:1904 and other Indian Standard.
21.6
All water retaining structures designed as an un-cracked section shall also be tested for
water tightness at full water level in accordance with clause No. 10 of IS:3370 (part-I)
21.7
Construction joints shall be as per IS:456
21.8
All underground concrete structures like basements, pumps houses, water retaining
structures etc. shall have plasticizer cum water proofing cement additive conforming to
IS:9103. in addition, limit on permeability as given in IS:2645 shall also be met with. The
concrete surface of these structures in contact with earth shall also be provided with two
coats of bituminous painting for water/damp proofing. In case of water leakage in the
above structures, Injection Method shall be applied for requiring the leakage.
2.12
1.0
TECHNICAL SPECIFICATIONS FOR 36 KV VACUUM CIRCUIT BREAKER
SCOPE
1.1
This section of specification covers the design, manufacture, assembly
under stringent quality control at every stage of manufacturing, testing at
manufacturer's works before dispatch, supply and delivery at destination
store and supervision of erection, testing and commissioning of 36 KV
outdoor type vacuum circuit breakers at various substations in SEB.
1.2
The scope of supply shall also include necessary special tools and plants
required for erection, maintenance and necessary spares, required for
normal operation and maintenance of the circuit breakers for a period of
five years.
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Technical Specification
1.3
The circuit breakers should be complete in all respects with insulators,
bimetallic connectors, interrupting chamber, operating mechanism control
cabinet, interlocks, auxiliary switches indicating devices, supporting
structures, accessories, etc., described herein and briefly listed in the
schedule of requirements. The spares/attachments which are meant
necessary for the smooth functioning of the equipment and specifically are
not mentioned here shall be assumed to be included the scope of supply.
1.4
It may be noted that the Vacuum Circuit Breaker must meet the following
minimum criteria. Failure to comply with the requirements may results in
rejection of the BID as non-responsive:
1.4..1 The Manufacturer must have designed, manufactured, type tested and supplied
vacuum circuit breaker in at least two power utilities of similar rating which are
in successful operation for at least 5 (Five) years as on the date of bid opening
which should be substantiated by furnishing performance report from the official
of the rank not below DGM/SE
1.5
The manufacturer of the VCB must use their own make Vacuum
Interrupters and must have in-house manufacturing facility for Vacuum
Interrupter & Breaker (including mechanism)
1.6
Design and construction of Vacuum Circuit Breaker shall be such that there
is no possibility for entry of moisture. There should not be any condensation
or accumulation of moisture on the internal insulating surfaces and
operating rod of the circuit breaker. For this purpose complete interrupter
housing and support insulator should be filled either with SF6 gas or with
Nitrogen or some other dielectric medium pressurized to avert
condensation. For monitoring positive gas pressure monitoring device shall
be provided by supplier for each pole. Bidder may please note that any
other device like heater, fan etc. which requires operation monitoring on
continuous basis are not acceptable to the purchaser.
2.0
STANDARDS
2.1
The circuit breaker shall conform in all respects to the requirements of
latest issue of IS/IEC specifications except for modifications specified
herein. The equipment manufactured according to any other authoritative
standards which ensure an equal or better quality than the provision of
IS/IEC specifications shall also be acceptable. The salient point of
difference between the proposed standard and provision of these
specifications shall be clearly brought out in the tender. A copy of English
version of such specifications shall be enclosed with the tender.
2.2
The list of standards mentioned in this specification and to which the circuit
conform is given below:
1.
IEC-56
High Voltage A.C. Circuit Breakers
2
IEC-137
Bushing for alternating voltage above 1000 volts
3.
IEC-71
Insulation Co-ordination
Common clauses for high voltages switchgear and control
4.
IEC-694
gear
standards
5.
IEC-815
Specification
for Creepage distance
Specifications for high voltage alternating current
6.
IS-13118
circuit
breakersporcelain bushings
7.
IS-2099
High voltages
8.
IS-4379
Identification of the contents of industrial gas cylinders
9.
IS-3072
Installation and maintenance of switchgear
Guide for testing of circuit breakers with respect to out
10.
IEC-267
of phase
switching
Code
of practice
for use of structural steel in overhead
11.
IS-802
transmission
lines
IEC-17A
12.
Sealing of interrupters I breakers
5tudy
Group
13.
IS-1554
PVC insulated cables upto and including 1000 volts
Dec.1981
14.
IS-5
Colors for ready mixed paints and channels
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Technical Specification
3.0
CLIMATIC CONDITONS
The breakers and accessories to be supplied against this specification shall be suitable
for satisfactory continuous operation under the tropical conditions specified in this
bidding document.
4.0
AUXILIARY POWER SUPPLY
4.1
Auxiliary electrical equipment shall be suitable for operation on the following
supply system.
a. Power Devices (like drive motors) 415 V, 3 phase 4 wire 50 hz, neutral grounded
AC supply
b. DC Alarm, Control and Protective Devices 110 V DC,
c. Lighting 240 V, single phase 50 Hz AC supply
4.2
5.0
5.1
5.2
Each of the foregoing supplies shall be made available by the Purchaser at the
terminal point for each circuit breaker for operation of accessories and auxiliary
equipment. Bidder's scope includes supply of interconnecting cables, terminal
boxes, etc. The above supply voltage may vary as indicated below and all
devices shall be suitable for continuous operation over the entire range of
voltages
1) AC Supply
415V (+ 10% /-- 15%)
2) Frequency
50Hz (± 5%)
2) DC Supply
110V ( - 15% to + 10%)
GENERAL REQUIREMENT OF 36 KV/OUTDOOR VACUUM CIRCUIT
BREAKERS
The vacuum type circuit breaker shall have vacuum interrupters, designed to
provide a long contact life at all currents upto rated making and breaking current during
switching operation: The vacuum interrupters sealed for life shall be encapsulated by
porcelain insulators for out door installation requirement of the circuit breakers. The
offered breakers shall be suitable for out door operation under climatic conditions
specified without any protection from sun, rain and dust storm.
The vacuum interrupters of each phase shall be housed in a separate porcelain
insulator. The three identical poles shall be mounted on a' common base frame and the
contact system of three poles should be mechanically linked to provide three pole gang
opening/closing for all type of faults.
i. The performance of breakers shall be adequately proven by type tests for the
designed rating at internationally reputed independent testing station.
ii. The offered equipment shall be practically maintenance free over a long period.
iii. All mechanical parts and linkages shall be robust in construction and
maintenance free, over at least 30,000 switching operations except for
lubrication of pins/articulated joints at interval of 5 years or 5000 operations.
iv) Similar parts shall be strictly interchangeable without special adjustment of
individual fittings. Parts requiring maintenance shall be easily accessible,
without requiring extensive dismantling of adjacent parts.
v) The operating mechanism will be self maintained and of proper operation
endurance not less than the mechanical life of circuit breaking unit. It shall be
spring operated type described hereinafter.
vi) The circuit breaker shall be supplied complete with all auxiliary equipment meant
necessary for the safe operation, routine and periodic maintenance. All internal
wiring including those of spare auxiliary contact.
vii)
viii) s shall be complete and wired upto terminal blocks situated near cable gland
plate.
ix) The breaker shall be totally restrike free under all duty conditions and shall be
capable of performing the duties without opening resistor. The details of any
device incorporated to limit or control the rate of rise of restriking voltage across
the circuit breaker contacts shall be stated.
x) The breaker shall be reasonably quiet in operation and the noise level shall not
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Technical Specification
exceed 140 decibels.
xi) The breaker shall be suitable for three phase reclosing operation.
xii) An operation counter, visible from the ground level even with the mechanism
housing closed shall be provided.
6.0
VACUUM INTERRUPTER ASSEMBLY
6.1
Each pole of the circuit breaker shall be provided with vacuum interrupter, one
for each phase, hermetically sealed for life and encapsulated by ceramic
insulators. The interrupter shall be provided with steel chromium are chamber to
prevent vaporized contact material being deposited on the insulating body. A
further shield giving protection to the metal bellows shall also follow the travel of
the moving contacts to seal the interrupter against the surroundings atmosphere.
6.2
It shall have high and consistent dielectric strength of vacuum unaffected by
environment and switching operations. Bronzed joints should ensure retention of
vacuum for life time. It shall have low and stable contact resistance due to
absence of oxidation effects and shall ensure low power loss. The arcing voltage
shall be low with minimum contact erosion.
6.3
The manufacturer of VCB should use their own Vacuum interrupter so that the
drive mechanism is matched perfectly with that of the requirement of Vacuum
Interrupter.
6.4
The vacuum bottles should be capable of withstanding minimum 100 full short
circuit operations as per test duty 1 to 5 of IEC-56. The vacuum bottles, capable
of withstanding less than 100 full short circuit faults, would not be considered
and therefore should not be offered.
6.5
A manufacture‘s type test reports / literature for vacuum bottles, may, therefore
be supplied along with tender in duplicate.
6.6
Vacuum Interrupters of China make should not be offered.
7.0
FIXED AND MOVING CONTACT
7.1
The fixed and moving contacts of the breaker have to ensure permanent full
contact during closing without unusual maintenance. All making and breaking
contacts shall be hermetically sealed and free from atmospheric effects.
7.2
The contacts metallurgy and geometry shall be such that there is minimum
contact burning and wear. Main contact shall have ample area and contact
pressure for carrying the rated current and rated short time current without
excessive temperature rise which may cause pitting or welding of the contacts.
7.3
7.4
8.0
The main contacts should have low contact resistance. The contact should be
self cleaning type, i.e., the layer of copper oxide should be cleaned during
rubbing of contacts. The contact area should be well defined, spring used for
contact shall be of gradually rising characteristic i.e., they should be soft. The
contacts should not provide contact grip, ie., electro-magnetic forces should not
grip the contacts and oppose the opening process. It would be desirable to have
separate main contacts and arcing contacts in order to have longer life of the
contacts. The contours of the energized metal parts of the breaker shall be such
as to eliminate areas or points of high electrostatic flux concentration. Surfaces
shall be smooth with no projection or irregularities which may cause visible
corona. No corona shall be visible in complete darkness when the equipment is
subjected to the specified test voltage.
The circuit breaker units shall be suitable for installation on outdoor R.C.C.
foundations. Ground clearance of the live parts of the breakers should be 3700
mm from foundation. The circuit breakers shall be spring operated.
RECOVERY VOLTAGE AND POWER FACTOR
8.1
The circuit breaker shall be capable of interrupting rated power with recovery
voltage equal to the rated maximum line to line service voltage at rated
frequency and at a power factor equal to or exceeding 0.15.
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Technical Specification
9.0
RESTRIKING RECOVERY and LINE CHARGING INTERRUPTING CAPACITY
9.1
9.2
9.3
The complete data for the phase factor, amplitude factor, etc., for rate of rise of
restriking voltage shall be furnished in the tender.
The circuit breaker shall be designed so as to be capable of interrupting line
charging currents without undue rise in the voltage on the supply side without
restrike and without showing sign of undue strains.
The maximum permissible switching over voltage shall not exceed 2.5 p.u. The
guaranteed over voltage, which will not be exceeded while interrupting the rated
line charging current for which the breaker is designed to interrupt shall also be
stated. The results of the tests conducted along with the copies of the
oscillographs to prove ability of the breakers to interrupt the rated as well as
lower values of the line charging current shall be furnished with the tender.
10.0
TRANSFORMER CHARGING CURRENT BREAKING CAPACITY
10.1 The breaker shall be capable of interrupting inductive currents, such as those
occurring while switching off unloaded transformers, without giving rise to undue
over voltage and without restrikes. The maximum over voltage value, which will
not be exceeded under such conditions, shall be stated in the tender.
11.0
BREAKING CAPACITY FOR SHORTLINE FAULTS
11.1 The interrupting capacity of the breaker for short line faults shall be stated in the
tender. The details of the test conducted for proving the capability of the breaker
under a short line fault occurring from one phase to earth conditions shall also be
stated in the tender. The rated characteristics for short line faults shall be in
accordance with stipulation contained in clause 8.0 of IEC-56(2)-1971.
12.0
AUTOMATIC RAPID RECLOSING and OUT OF PHASE SWITCHING
12.1
12.2
36 KV circuit breaker shall be suitable for 3 pole rapid reclosing. The dead time
of the breaker shall be adjustable and the limits of the adjustment shall be stated
in the tender.
The circuit breaker shall be capable of satisfactory operation even under
conditions of phase opposition that may arise due to faulty synchronization. The
maximum power that the breaker can satisfactorily interrupt under "Phase
Opposition" shall be stated in the bid".
13.0
TEMPERATURE RISE
13.1 The maximum temperature attained by any part of the equipment when in
service at side and under continuous full load conditions and exposed to the
direct rays of the sun shall not exceed the permissible limits fixed by IEC. When
the standards specify the limits of temperature rise these shall not be exceeded
when corrected for the difference between ambient temperature specified in the
approved specification.
13.2 The limits of temperature rise shall also be corrected for altitude as per IEC and
stated in the bid.
14.0
INSULATORS SUPPORTS AND HOUSING
14.1 The basic insulation level of the external insulator supporting shall be as stated
in the "Technical Parameters" and these shall be suitable for use under climatic
conditions as stated elsewhere in the specification. The porcelain used shall be
homogenous, free from cavities and other flaws.
14.2
The insulators shall be designed to have ample insulation, mechanical strength
and rigidity for satisfactory operation under conditions specified above.
14.3 All bushings of identical rating shall be interchangeable. The puncture strength of
bushing shall be greater than the flash over value. The design of bushing shall
be such that the complete bushing in a self-contained unit and no audible
discharge shall be detected at a voltage upto a working voltage (Phase Voltage)
plus 10%. The support insulator shall conform to IEC-137.
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Technical Specification
14.4
14.5
Minimum clearance between phases, between live parts and grounded objects
shall be as per IS-3072-1975 and should conform to Indian Electricity Rules1956. The minimum creepage distance for severely polluted atmosphere shall be
27 mm/KV.
. The air clearance of bushing should be such that if the bushings were tested at
an altitude of less than 1000 meters, air clearance would withstand the
application of higher voltages (IS-2099-1973 para 6.1). In order to avoid
breakdown at extremely low pressures the support insulators should not be
covered by moisture and conducting dust. Insulators should therefore be
extremely clean and should have anti-tracking properties. Sharp contours in
conducting parts should be avoided for breakdown of insulation. The insulators
shall be capable to withstand the seismic acceleration of 0.5 g in horizontal
direction and 0.6g in vertical direction.
15.0
OPERATING MECHANISM GENERAL REQUIREMENTS
15.1 The operating mechanism shall be stored energy type and capable of giving
specified duty of the breaker The breaker shall also pass the operational test
which ascertain the capabilities of operating mechanism. The operating
mechanism shall be capable to perform the following functions efficiently.
i) To provide means where the circuit breaker can be closed rapidly, without
hesitation at all currents from zero to rated making current capacity.
ii) To hold the circuit breaker in closed positions by toggles or latches till the
tripping signal is received.
iii) To allow the circuit breaker to open without delay immediately on receiving
tripping signal.
iv) Operating mechanism should also be suitable for three phase auto reclose duty.
The closing spring shall be automatically charged by motor immediately after
closing operation.
v) In case of failure of supply to the spring charging motor, the spring shall be
chargeable by hand crank.
vi) The contact pressure spring and tripping spring shall be chargeable during
closing operation to ensure the breaker is ready to open.
vii) Mechanically ON/OFF indicator, spring charged indicator and operation counter
shall be provided on the front of the control cubicle. For tripping, the spring
provided shall ensure the trippings.
16.0
Tripping/Closing Coils
16.1 The circuit breakers shall be provided with two trip coils and one closing coil per
breaker. First trip coil shall be utilized for tripping the breaker on main protection
fault detection. Whereas second trip coil shall be used to trip the breaker when
first trip coil fails to trip the breaker and backup protection comes into operation
and shall also be used to trip the breaker on command.
16.2 The trip coils shall be suitable for pre-closing and after closing trip circuit
supervision. All the breakers shall have provision for independent electrical
operation of trip coils from local as well as remote through local/remote selector
switch. The breaker shall be provided with suitable protection device against
discrepancies in the operation of individual pole.
16.3 Closing coil shall operate correctly at all value of voltage between 85% and
110% of the rated voltage. Shunt trip coils shall operate correctly under all
operating conditions of the circuit breaker upto the rated breaking capacity and
at all values of supply voltage between 70% and 110% of rated voltage.
16.4 Trip Free Features
a.
When the breaker has been instructed to close by manual instructions by
pushing of push button, the operating mechanism will start operating for
closing operations. If in the mean time a fault has taken place, the relay
provision shall be such that it should close the trip circuit simultaneously
interrupting the live circuit of closing coil which has been instructed for close
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Technical Specification
command.
b.
The trip free mechanism shall permit the circuit breaker to be tripped by
the protective relay even if it is under the process of closing. An antipumping
device to prevent the circuit breaker from reclosing after an automatic opening
shall be provided to avoid the breaker from pumping i.e., anti pumping relay
should interrupt the closing coil circuit.
17.0
Controls
17.1 The circuit breaker shall be controlled by a control switch located in the control
room. The control arrangement shall be such as to disconnect the remote control
circuits of the breaker, when it is under test.
17.2
Local control devices, selector switch and position indicator shall be located in
weather and vermin-proof cabinet.
17.3 The circuit breaker control scheme shall incorporate trip circuit supervision
arrangement. Local/remote selector switch shall be provided for all breakers for
selection of "Local" control/remote control. Provision shall be made for local
manual, electrical and spring controls. Necessary equipment's for local controls
shall be housed in the circuit breaker cabinet of weather-proof construction. In
addition to this, a hand closing device for facilitating maintenance shall also be
provided.
17.4 Each circuit breaker shall have a mechanical open/closed and spring charge
indicator in addition to facilities for provisions for semaphore indicators for
breakers which are required for the mimic diagram in the control room.
17.5 Lamps for indicating, 'close/open' position of the breaker shall also be provided.
17.6
Mechanical indicator, to show the 'open' and 'close' position of the breaker shall
be provided in a position where it will be visible to a man standing on ground with
mechanism housing open. An operation counter, visible from the ground even
with the mechanism housing closed, shall be provided. Electrical tripping of the
breaker shall be performed by shunt trip coils.
17.7 Operating mechanism and all accessories shall be enclosed in control cabinet. A
common marshalling box for the three poles of the breaker shall be provided,
along with supply of tubing, cables from individual pole operating boxes to the
common marshalling box, local.
18.0
SPRING OPERATED MECHANISM and MOTOR
18.1 The motor compressed spring mechanism shall consist of a closing spring which
is wound or compressed by an electric motor immediately after the breaker
closes. The closing action shall also wind or compress a tripping springs shall be
wound.
18.2 After the breaker has tripped, the tripping spring shall remain in the released
position as long as the breaker is open, but the closing spring shall remain
wound and ready for closing operation. Spring charging motor shall be standard
single phase universal motor suitable for 220 volts supply.
i) Operating voltages for closing/tripping coils shall be 110 Volts DC.
ii) Operating voltages for heater elements shall be 220V AC 50 HZ. Other features
of the spring operated mechanism shall be as follows.
18.3 The spring operating mechanism shall have adequate energy stored in the
operating to close and latch the circuit breaker against the rated making current
and also to provide the required energy for tripping mechanism in case the
tripping energy is derived from the operating mechanism.
18.4 The mechanism shall be capable of performing the rated operating duty cycle of
0-0.3Sec-CO-3 Min-CO as per IEC-56.
18.5 The spring charging motor shall be AC/DC operated and shall not take more than
30 sec., to fully charge the closing spring made for automatic charging. Charging
of spring by the motor should not - interfere with the operation of the breakers.
18.6 The motor shall be adequately rated to carry out a minimum of one duty cycle.
Also provision shall be made to protect the motor against overloads.
18.7 In case of failure of power supply to spring charging motor, the
mechanism shall be capable of performing one open-close-open operation.
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Technical Specification
18.8
18.9
19.0
19.1
19.2
19.3
19.4
19.5
19.6
19.7
19.8
Mechanical interlocks shall be provided in the operating mechanism to prevent
discharging of the closing springs when the breaker is already in closed position.
Provision shall be made to prevent a closing operation to be carried out with the
spring partially charged.
Facility shall be provided for manual charging of closing springs.
CONTROL CABINET
The switchgear operating mechanism, the control equipment such switch for
closing and tripping the breakers, various control relays, antipumping device, timer for
adjusting breaker reclosing, a set of terminal blocks for wiring connections, MCB's for
disconnecting the control auxiliary power supplies. Including relays, etc., shall be
enclosed in a cabinet to 'be mounted on a suitable structure at a convenient working
height at the end of the breaker in the outdoor switchyard. The supporting structure and
the enclosure shall be capable of withstanding the typical tropical climatic conditions,
change of ambient temperature, severe dust-storms, very high relative humidity those
are prevailing at the site of location of switchgear .
The enclosure shall be made out of stretched level steel plates not less than
3.15 mm thick and of light section structural steel. It should be weather proof as well as
vermin proof and conforming to IP: 55 degree of protection.
Each cabinet section shall have full width and full length hinged doors mounted
on the front that swing fully open. The doors shall be provided with latches to securely
hold it with the cabinet. Doors shall be of sturdy construction, with resilient material
covering, to provide dust protection and prevent metal to metal contact except at the
latch points. Filtered ventilation shall be provided along with the rigid supports for
control and other equipment, measuring instruments, mounting cabinet members and
equipment shall not restrict easy access to terminal blocks for terminating and testing
external connection or to equipment for maintenance.
All screws and bolts used for assembling and mounting wire and cable
termination, supports, devices and other equipment shall be provided with lock washers
or other locking devices. All metal parts shall be clean and free of weld splatter, rust and
mill scale prior to application of double coat of zinc chromate primer which should be
followed by an Polyurethane paint to serve as base and binder for tile finishing coat.
The exterior of the cubicle shall be painted matty grey to shade NO.692 of IS-5 or shade
No.631 and interior to white shade. Sufficient quantity of paints shall also be supplied
along with the cubicle to restore at site any damage during transportation. The mounting
structure shall be galvanized and shall be as per IS-802-11-1978.
Suitable heaters shall be mounted in the cabinet to prevent condensation.
Heaters shall be controlled by thermostat ON/OFF switches and fuses shall be
provided. Heaters shall be suitable for 240 V AC supply voltage.
At least one 20 watts fluorescent tube fixture and lamp holder working on 240V,
50 c/s AC supply shall be provided in each switchgear control cubicle section and shall
be located to provide adequate interior lighting of the cubicle. Ballasts shall be rated at
not less than 0.90 power factor. A single pole 20 Amp. ‗T‘ rated lighting switch shall be
provided for each cubicle, flush-mounted on the left end. One duplex 220 volt
convenience outlet shall be provided inside each door or pair of doors inside each
cubicle. The lighting and convenient outlet circuits shall be completely wired in conduit
and terminated on cubicle terminal blocks.
Unless otherwise specified control wire shall be stranded tinned copper stranded
wire with 1.1 KV PVC insulation conforming to the requirements of IS-1554.
All the control circuit and secondary wiring shall be wired completely and brought out
preferably to a vertical terminal block ready for external connections in the control
cabinet. The control wire shall not be of cross-section less than 2.5 mm2 copper.
All spare auxiliary contacts of the circuit breaker shall be supplied wired upto
terminal block.At least 20 number spare terminals shall be provided over and above the
number required. All wiring termination on terminal blocks shall be made through lugs.
For current and DC supply circuits disconnecting sturdy type terminal blocks will be
provided. For other control circuits, non-disconnecting snap on type terminal blocks shall
be provided.
All wires shall be identified with non-metallic sleeve or tube type markers at each
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
terminations.
Terminal blocks shall be made up of molded non-inflammable plastic material
with blocks and barriers molded integrally have white marking strips for circuit
identification and moulded plastic covers.
19.10
A ground bus of copper bar not less than 6 mm by 25 mm shall be provided
along the inside of the front or rear of the each cubicle and equipment rack. The ground
bus shall be bolted to the frame of each panel in such a way as to make good electrical
contact with each panel or section. Lugs shall be provided for connection of the ground
bus to the station ground bus/earth mat.
19.9
20.0
20.1
ACCESSORIES
Each circuit breaker assembly shall be supplied with the following accessories.
i)
Line and earthing terminals and terminal connectors.
ii)
Control housing with:
a)
One auxiliary switch with adequate number of auxiliary contacts, but not less
than 12 nos. (6 No + 6 NC) for each breaker. These shall be over and above the
No. of contacts used for closing, tripping and 'reclosing' and interlocking circuit of
the circuit breaker. All auxiliary contacts shall be capable of use as "Normally
closed" or "Normally open" contacts. Special auxiliary contacts required for the
reclosing circuit if any, shall also be provided. There shall be provision, to add
more auxiliary contacts at a later date, if required.
b)
Operation counters
c)
Position indicator (Close/Open)
d)
Necessary cable glands
e)
Fuses
f)
Manual trip device and local test push buttons
g)
Terminal blocks and wiring for all control equipment and accessories
h)
Adequate number of heaters for continuous operation to prevent moisture
condensation in the housing of operating mechanism
i)
Selector switch for local/remote control.
21.0
SUPPORTING STRUCTURE
21.1 The circuit breakers shall be supplied complete with necessary galvanized steel
supporting structures, foundation and fixing bolts, etc., the galvanizing shall be
as per IS. The mounting of the breaker shall be such as to ensure the safety of
the operating staff and should conform to Indian Electricity Rules, 1956.
Minimum ground clearance of live part from ground level shall be 4000 mm
inclusive of foundation (300mm above GL).
21.2 The bidder shall submit detailed design calculations and detailed drawings in
respect of supporting structures suitable for the equipment offered. The tenders
shall specify the loads which shall be transmitted to the equipment foundation
under most adverse operating conditions of the breaker.
21.3 Facility to earth the circuit breaker structure at two points shall be provided.
22.0
GALVANISING
All ferrous parts including all sizes of nuts, bolts, plain and spring washers, support
channels, structures, shall; be hot dip galvanized conforming to latest version of
18:2629 or any other equivalent authoritative standard.
23.0
CABLE TERMINATION
Suitable cable glands for terminating the multi-core cable shall be provided wherever
required.
24.0
TERMINAL CONNECTIONS AND EARTH TERMINALS
24.1 Each circuit breaker connected with incoming and outgoing feeders shall be
provided with solder less clamp type bimetallic connectors suitable for
ACSR/AAAC conductor mentioned in 'Technical Parameter'
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
25.0
INTERTERLOCKS
25.1 Necessary interlocks to prevent closing or opening of the breaker under low
pressure of the contact spring and devices for initiating alarm shall be provided.
Provision shall also be made to enable electrical interlocking with the isolators
associated with the breaker to prevent opening or closing of the isolators.
26.0
TYPE TESTS
26.1 Type test certificates for the following tests, as per IS:13118 or IEC 62271-100
with latest amendment thereof, from any of the NABL accredited Laboratory shall
invariably be furnished
a. Short circuit duties test
b. Short time withstand current and peak withstand current tests
c. Temperature rise test
d. Mechanical endurance test
e. Lightning impulse voltage withstand test
f. Power Frequency withstand voltage test (dry & wet)
g. Single Capacitor bank switching test
h. Degree of protection IP-55 as per IS:13947:93(Part-I)/IEC 60529:89
26.2
26.3
26.4
27.0
Type test certificates must accompany drawing of type tested equipment, duly
sealed & signed by type testing authority.
Type tests conducted on the equipment should not be earlier than 3 years from
the date of opening of bids.
In case of any change in design/type of breaker already type tested and the one
being offered against this specification, the Employer reserves the right to
demand repetition of some or all tests without any extra-cost at NABL accredited
lab.
ACCEPTANCE AND ROUTINE TEST :27.1 Employer shall have access at all times to the works and all other places of
manufacture where the Circuit Breakers are being manufactured and the Bidder
shall provide all facilities for unrestricted inspection of the Bidder/manufacturer‘s
works, raw materials, manufacture of all the accessories and for conducting
necessary tests as detailed herein. The Employer reserves the right to insist for
witnessing acceptance/routine testing of the bought out items. The
Bidder/manufacturer shall submit the routine test certificates of bought out items
and raw material also, at the time of routine testing of the fully assembled
breaker
27.2 No material shall be dispatched from its point of manufacture unless the material
has been satisfactorily inspected and tested.
27.3 Bidders shall indicate the inspections and checks carried out at various stages of
manufacture of the circuit breakers. Complete record of stage inspection would
be kept by the Bidder/manufacturer and this record should be made available for
inspection by the representative of the Employer. Bidder/manufacturer should
indicate the manufacturing programme and the The Employer will have a right to
depute inspecting officers during the manufacture of the equipment. The
Employer reserves the right to carry out stage inspections at all stages, for which
advance intimation shall be given and all necessary cooperation shall be
rendered by the manufacturer.
27.4 At the time of inspection, Bidder/manufacturer shall identify each and every
item/accessories of the particular Circuit Breaker under testing. Unless all the
items are identified, the manufacture will not be treated as complete. Various
tests stipulated in IS/IEC shall be performed in the presence of the Employer‘s
engineers or when the inspection waiver has been given, in such a case, testing
shall be done at the manufacturer's works as per IS/IEC stipulations and same
should be confirmed by documentary evidence by way of Test Certificate which
shall be got approved by the Employer.
27.5
It is expected that before circuit breaker is finally offered for inspection, internal
testing of the same for various important parameters are already done. Routine
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
27.6
27.7
test report for such tests shall also accompany the letter of inspection call so that
the Inspecting Officer at the time of inspection may verify the parameters brought
out in the preliminary report. Details of all tests should be clearly brought out.
In case for any reason, inspection is not completed or equipment is not found to
be complete with all accessories as per confirmation given with the letter of
inspection call, the Employer will reserve the right to recover complete cost of
deputation of inspecting team to the works of the manufacturer.
Acceptance of any quantity of circuit breaker & its accessories shall in no way
relieve the successful bidder of his responsibility for meeting all the requirement
of this specification and shall not prevent subsequent rejection if such
equipments are later found to be defective.
28.0
RATING PLATES & SURFACE FINISH PAINTING & GALVANISING:28.1 Each circuit breaker shall be provided with a detailed rating plate. Details on the
rating plate shall be as per ISS and shall also indicate manufacturer name, serial
no., order no. and month & year of dispatch and Name of Project--RAPDRP.
28.2 All interiors and exteriors of tanks, mechanism, enclosures, cabinets and other
metal parts shall be thoroughly cleaned to remove all rust, scales, corrosion,
greases or other adhering foreign matter. All steel surfaces in contact with
insulating oil, as far as accessible, shall be painted with not less than two coats
of heat resistant, oil insoluble, insulating paint.
28.3 All metal surfaces exposed to atmosphere shall be given two primer coats of zinc
chromate and two coats of epoxy paint with epoxy base thinner or hot dip
galvanized or two packs of aliphatic polyurethane finished paint. All metal parts
not accessible for painting shall be made of corrosion resistant material. All
machine finished or bright surfaces shall be coated with a suitable preventive
compound and suitably wrapped or otherwise protected. Paints shall be carefully
selected to withstand tropical heat and extremes of weather within the limits
specified.
28.4 Paint shall not scale off or wrinkle or be removed by abrasion due to normal
handling. All external paintings shall be as per shade no. 697 or any other
suitable shade of IS:5 or polyurethane paint
28.5 All ferrous parts & steel structure including all sizes of nuts, bolts, plain and
spring washers, support channels, structures, etc. shall be hot dip galvanized or
stainless steel or electro-galvanized.
29.0
DOCUMENTATION:
29.1 List of Drawings and Documents: Bidders shall furnish four sets of relevant
descriptive and illustrative published literature, pamphlets and following drawings
for preliminary study;
(a) General outline drawings showing dimensions and shipping weights.
(b) Sectional views showing the general constructional features of the
circuit breaker including operating mechanism, arcing chambers, contacts
with lifting dimensions formaintenance.
(c) All drawings & data typical and recommended schematic diagram for
control
supervision & reclosing shall be annotated in English. .
(d) Schematic diagrams of breaker offered for control supervision and
reclosing.
(e) Structural drawing, design calculations and loading data for support
structures.
(f) Short circuit oscillogram & certificates for similar type tested breakers.
General
arrangement of foundation and structure mounting plan including weights of
varnish
components and impact loading data for foundation design.
(g) Type test reports.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
29.2
29.3
29.4
29.5
30.0
Successful bidders shall, within two weeks of placement of order, submit four
sets of final version of all the above drawings for the Employer's approval. The
Employer shall communicate his comments/approval on the drawings to the
Bidder/manufacturer within two weeks. Bidder/manufacturer shall, if necessary,
modify the drawings and resubmit four copies of the modified drawings for the
Employer's approval within two weeks from the date of comments. After receipt
of the Employer's approval, the Bidder/manufacturer shall, within three weeks,
submit 4 prints per breaker and two set of good qualities reproducible of the
approved drawings for the Employer's use.
Successful bidders shall also furnish two sets each of bound manuals covering
erection, commissioning, operation and maintenance instructions and all relevant
information and drawings pertaining to the main equipment as well as auxiliary
devices along with each breaker. Marked erection drawings shall identify the
component parts of the equipment as shipped to enable erection by the
Employer‘s own personnel. Each manual shall also contain one set of all the
approved drawings, type test reports as well as acceptance reports of the
corresponding consignment dispatched.
Manufacturing of equipments shall be strictly in accordance with the approved
drawings and no deviation shall be permitted without the written approval of the
Employer.
Approval of drawings/work by the Employer shall not relieve the bidders of any of
his responsibility and liability for ensuring correctness and correct interpretation
of the drawings for meeting the requirements of the latest revision of the
applicable standards rules and codes of practices. Equipment shall conform in all
respects to high standards of engineering, design, workmanship and latest
revisions of relevant standards at the time of supply and the Employer reserves
the right to reject any equipment or material which, in his judgment, is not in full
accordance therewith.
PACKING AND FORWARDING:
30.1 Equipment shall be prepared for ocean shipment (foreign equipment) or rail road
transport (local equipment). Equipment shall be packed in suitable crates in such
a manner to protect it from damage and withstand handling during transit.
Bidder/manufacturer shall be responsible for and make good at his own expense
any or all damage to the equipment during transit, due to improper and
inadequate packing and handling. Easily damageable materials shall be carefully
packed and marked with the appropriate caution symbols. Wherever necessary,
proper arrangement for lifting such as lifting hooks etc. shall be provided. Any
material found short inside the packing cases shall be supplied by the
Bidder/manufacturer without any extra cost. Each consignment shall be
accompanied by a detailed packing list containing the following information:
(a) Name of the consignee.
(b) Details of consignment.
(c) Destination.
(d) Total weight of consignment.
(e) Sign showing upper/lower side of the crate.
(f) Handling and unpacking instructions.
(g) Bill of material indicating contents of each package and spare material.
31.0
COMPLETENESS OF EQUIPMENT AND BOUGHT OUT ITEMS:
31.1 Bidders must furnish following information along with technical bid. A list of all
the accessories which will be supplied with the breakers should be furnished.
While furnishing the list of accessories, items which will be manufactured by the
Bidders and balance items, which will be procured from subBidder/manufacturers should be clearly identified and stipulated in the bid.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
32.0
SN
1.
GUARANTEED TECHNICAL PARTICULARS:
32.1 It is obligatory on the part of bidders to furnish Guaranteed Technical Particulars
enclosed with the bid document duly filled in complete in all respects. In case
Guaranteed Technical Particulars duly filled in complete in all respects is not
furnished, the bid may be treated as non-responsive.
32.2 The salient technical particulars of the VCB should be as follows:
Type of Circuit Breaker
Standards Applicable
2.
Nominal System Voltage (KVrms)
3.
Highest system voltage
4. Rated continuous current at design temperature of 50 deg.C
(Amps)
Rated Frequency (Hz)
5.
Design ambient temperature
6.
Maximum temperature rise for main contacts over desugn
7.
ambient temperature of 50 deg.C
Short time current rating (kA)
8.
Rated Operating Duty
9.
Operating Mechanism
10.
a) Type of operating mechanism for
i) Closing
11.
ii) Opening
Dielectric withstand voltage
12.
i) One minute dry & wet power frequency withstand voltage
a) Between live terminal and ground (kVrms)
b) Between terminals with breaker contacts open (kVp)
13.
ii) 1.2/50 micro second impulse withstand test voltage
a) Between live terminal and ground (kVp)
b) Between terminals with breaker contacts open (kVp)
Vacuum ,Outdoor
IEC 62271-100 & IS
13118
33 kV
36kV
1250A
50
50 deg
40 deg.C
25 kA for 3 sec
0-0.3 sec-CO-3 min-CO
Spring Charging
Spring Charging
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70
70
170
170
53
Technical Specification
TECHNICAL SPECIFICATION OF 33 KV & 11KV
2.13
1.0
TECHNICAL SPECIFICATION FOR 33 KV and 11 KV AUTO RECLOSER WITH
COMMUNICATION MODEM
SCOPE
The specification covers the design, manufacturing, testing, supply, installation,
testing and commissioning of 33/11kV Un-manned substation made with outdoor
pole mounted auto-recloser that have programmable protection features and
integrated remote operation capability and that are intended for distribution
networks at nominal A.C. voltages of 36/12 kV.
A primary objective of this specification is to foster modularity and a maximum
level of interchangeability and integration to central SCADA system by
supporting MODBUS/DNP3/IEC-103 and IEC60870-5-101/ IEC60870-5-104
communications protocols.
2.0
APPLICABLE STANDARDS
The following standards contain provisions that, through reference in the text,
constitute requirements of this specification at the time of publication the
revisions indicated were valid. All standards are subject to review and parties to
purchasing agreements based on this specification are encouraged to
investigate the possibility of applying the most recent revisions of the standards
listed below.
ANSI/IEEE C37.60-1981: Requirements for overhead, pad mounted, dry vault,
and submersible automatic circuit reclosers and fault interrupters for AC
systems (RI993)
IEC 60255, Electrical relays
IEC 60056:1987, High-voltage alternating-current circuit breakers. Amendment
No. 1:1 992.
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code).
UNIPEDE NORM (SPEC) 13 (1995): Automation and Control Apparatus for
Generating Stations and Substations: Electromagnetic Compatibility Immunity
Requirements.
2.1 CLIMATIC CONDITIONS
The Substation shall be suitable for satisfactorily working under the following
climatic conditions: Max. Ambient Temperature
Min. Ambient Temperature
Max. Relative Humidity
Min. Relative Humidity
Altitude
550 C
20 C
100 %
56 %
Below 1000 meters above mean
sea level.
The switch Switchgears and Auto-reclosers used shall be suitably designed and
treated for normal life and satisfactory operation under the hot and hazardous
tropical climate conditions and shall be dust and vermin proof. All interior and
exterior ferrous surfaces of auto-reclosers and control cabinets shall be
manufactured from marine grade stainless steel. All support structures and
associated bolts and nuts with these parts, shall be hot-dip galvanized.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
3.0
TECHNICAL DATA SHEET FOR AUTO RECLOSER
Sl.
No.
1
Particulars
2
No of poles
3
4
5
6
Service
Rated System Voltage
Highest System Voltage
System earthing
7
8
12
13
Rated Voltage of AR
kV
Rated Continuous Current
Amps
a) For lines
b) For Transformers
Rated Frequency
Hz
Rated Short Circuit breaking
kA RMS
current ( I )
- 3secs – symmetrical
Rated Short Circuit making current
kA
PEAK
Interrupting medium
Insulation medium
14
15
16
17
Closing mechanism
Opening mechanism
Mounting type
Enclosure
18
19
Duty cycle
20
Insulation level
21
i) Power Frequency with Stand
kV RMS
Voltage
ii) Impulse withstand Voltage
kV Peak
Minimum clearance between
mm
phases
Minimum clearance between phase
to earth
9
10
11
22
23
Unit
Type
Minimum Creepage Distance
(Total)
Operating mechanism:
kV
kV
Data for
33kV AR
SF6
Data for
11kV AR
Solid
3
(3 Phase Ganged
Unit)
3
(3 Phase
Ganged Unit)
Outdoor
33
38
Solidly earthed
system
36
Outdoor
11
15.5
Solidly earthed
system
12
800
400
50
16
630
630
50
12.5
2.5*I
2.5*I
Vacuum
SF6 /Solid Dielectric
LV Solenoid
Springs
Single pole
316 grade
stainless steel
Vacuum
Solid dielectric
LV Solenoid
Springs
Single pole
316 grade
stainless steel
O-1strt-CO-2ndrt-CO-O-1strt-CO-2ndrt-CO3rd
3rd
rt-CO
rt-CO
CO
CO
mm
70
60
170
400
110
375
400
295
1100
780
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
Sl. Particulars
No.
a) Type
Unit
Data for
Data for
33kV AR
11kV AR
Solenoid-Spring Solenoid-Spring
.c) Rated voltage of Shunt trip coil
& operating range
V. DC
110[50% - 110%]
d) Rated voltage of Closing coil &
operating range
e) No. of trip coils
f) No. of closing coils
g) Nos of expandable auxiliary I/O
contacts & contact rating
(Required for transformer &
Incomer AR)
V. DC 110 [80% - 110%]
110 [50% 110%]
110 [80% 110%]
No
2 per AR
2 per AR
No
1 per AR
1 per AR
Nos
12 I/P+8 O/P 12 I/P+8 I/P (per
AMPS
(per AR)
CB)
10 A at 240V AC 10 A at 240V AC
& 10A at 110V DC & 10A at 110V
DC
h) Minimum thickness of sheet steel mm
3
3
for control cabinet
i) Enclosure Protection
IP55
IP55
24
Reclosing
Three Phase
Three Phase
auto reclosing
auto reclosing
25
Support structure
Galvanised
Galvanised
(Painted / Galvanised)
26
All other parts (Painted /
Synthetic enamel
Synthetic
Galvanised)
shade
enamel shade
631 of IS5
631 of IS5
(125 microns)
(125 microns)
27
28
29
Minimum size of control wiring
(Copper)
Protection
a) For transformer
b) For line
30
Measurement
31
Communication Protocol
32
Communication Port
33
Supervisory
Sq. mm
2.5
Numeric O/C, E/F, SEF,
relay Differential, OTI,
WTI, PRV,
Buchholz, OSR
with Backup
-doScheme
O/C, E/F, SEF
2.5
O/C, E/F, SEF
Differential,
REF, with
Backup
Scheme
O/C, E/F, SEF
Digital Real time current,
Real time
voltage, PF
current, voltage,
PF
IEC60870-5-101/ IEC60870-5-101/
IEC60870-5-104 IEC60870-5-104
and IEC
and IEC
103/DNP
103/DNP
3/MODBUS for 3/MODBUS for
meters & Relays meters & Relays
RS 232, RS 485 RS 232, RS 485
& Ethernet
& Ethernet
RTU
RTU
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
4.0
DEFINITIONS AND ABBREVIATIONS
4.1
Auto-recloser (AR): A mechanical switching device that, after opening, closes
automatically after a predetermined time. Several reclosures could occur before
lockout.
4.2
Cold load pick-up (CLP) feature: A feature that allows modification of the overcurrent protection characteristics in order to prevent relay maloperation under
conditions of system energisation.
Dead time: The time between the instant that the current is interrupted by the
AR and the instant the contact of the AR closes as a result of an automatic
reclose operation. [IEC 50-448-04-09]
Definite time lag (DTL) protection element: A protection element with a
settable time delay that is constant above the pick-up current setting.
Delayed protection operation: The protection functionality enabling delayed
circuit-breaker operation, whether this is due to an IDMTL or DTL protection
element.
Disc reset time: The time required for the disc of an electromechanical IDMTL
protection relay to turn back to its original position after it has turned to the
position where a protection operation was initiated.
Effectively earthed system: An earthed system in which the healthy phase
power frequency phase-to-earth over voltages associated with earth faults are
limited to 80% of the highest phase-to-phase voltage of the system.
Fast curve protection element: A family of curves with operating times
approximately constant (slightly inverse) relative to the multiple of pick-up
setting.
Instantaneous protection element: An element with no intentional time delay
active above a pre-determined pick-up current setting.
Inverse definite minimum time (IDMT) protection element: A protection
element the minimum operating time of which is adjustable and is inversely
proportional to the fault current.
Pole-mounted remote terminal unit (PMRTU): A remote terminal unit that is
designed for pole mounting and that operates specific pole-mounted equipment
remotely.
Rapid protection operation: The protection functionality enabling rapid circuitbreaker operation, whether this is due to an instantaneous, fast curve, or a
definite time delay protection element with relatively short definite time delay.
Reset time: The time duration after a circuit-breaker close operation for which
the measured currents are below a fault detecting level. On the expiry of this
time the protection sequence resets.
Secure control: A single mechanically non-latching switch that effects one state
of a control function only. An example of which is either a non-latching switch or
two separate push buttons that effect one state of a control function only in each
position. If a control is activated repeatedly it only effects that state and does not
change the state of the control.
Sensitive earth fault (SEF) relay: A relay that is sensitive to very low earth fault
currents and in which the operating settings are for current magnitude and
definite time delay.
Supervisory: Remote control and indications of an AR or a PMRTU by means
of a telecommunications link.
Toggled control: A single mechanically non-latching switch/push-button that
enables a single control function on the first operation of the switch/push-button
and disables the function on the second operation of the same switch/push
button.
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
4.15
4.16
4.17
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
4.18 Zone sequence co-ordination (ZSC): The feature that allows protection
devices to maintain sequence co-ordination for combinations of rapid and
delayed protection operations.
5.0
Mounting
5.1
The AR shall be suitable for single pole mounting.
5.2
Adequately rated lifting eyes shall be provided and they shall be designed to
allow the completely assembled AR (surge arresters fitted) to be lifted without
recourse to a sling spreader. The diameter of the eyes shall be a minimum of
30mm.
Suitable mounting brackets for surge arresters shall be provided on the line side
and on the load side of the AR, adjacent to the bushings.
The AR shall be fitted with an external M12 earthing stud, complete with a nut,
lock nut and spring washer.
The AR shall have laser cut markings on each bushings marked U1 V1 W1 for
the normal line side and U2 V2 W2 for normal load side.
A detailed drawing of the single pole AR mounting arrangement with surge
arresters fitted shall be provided. The minimum phase-to-earth clearances shall
be as per relevant IS and is to be indicated on the drawing.
The mass of the mounting hardware, the AR and the control cabinet and cable
shall be stated in the tender documentation.
Bushings
5.3
5.4
5.5
5.6
5.7
6.0
6.1 Terminals
a)
For 33KV AR, the preferred arrangement for bushing is a fully insulated
bushing arrangement achieved by using cyclo aliphatic epoxy resign
bushings and silicone rubber bushing boots together with 3 meters 185
mm2, single core, XLPE insulated aluminum water blocked cable tails to
provide a fully insulated bushing arrangement.
b)
For 11 KV AR, the preferred arrangement for connection to overhead
conductor is using crimp lugs with holes.
6.2 Material
The following bushing materials are acceptable:
a)
Outdoor Cyclo aliphatic epoxy resin and/or Silicone rubber
b)
Porcelain bushings and EPDM rubber are not acceptable.
c)
Minimum acceptable creepage is 1100 mm for 33 KV AR and 780 mm for
11KV AR..
7.0
Finish
a)
All interior and exterior ferrous surfaces of auto-reclosers and control
cabinets shall be manufactured from 316 marine grade stainless steel.
All support structures and associated bolts and nuts with these parts, shall
be hot-dip galvanized.
b)
Suitable precautions shall be implemented to prevent corrosion due to the
use of dissimilar materials.
8.0
Control equipment
8.1 Control cabinet
a)
b)
c)
Cabinets that house equipment for protection and control shall be mounted
independently of the AR.
Suitable ultraviolet-resistant cable, shall be provided to connect the AR to
the control cabinet.
It shall be possible to disconnect the cable at the AR while the AR is
connected to the power system, without causing damage or mal-operation:
care shall be taken that CTs are not open circuited. A robust, multi-pin
weatherproof connector shall be supplied. The female part of the
connector shall be mounted on the AR and the male part shall be mounted
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Technical Specification
on the cable. Preference will be given to products supplying connectors at
both the AR and the control cabinet.
d)
Cabinets shall be adequately sealed and dust protected and shall be
internally treated to prevent moisture condensation. The degree of
protection shall be IP 55.
e)
The supplier shall ensure that the equipment housed in the control cabinet
can withstand the heating effect of direct solar radiation without causing
failure and/or mal-operation. Details shall be provided in the tender
documentation.
f)
The cabinet shall make provision for bottom entry of three cables. This
shall be done with a pre-punched suitable sized diameter holes. The holes
shall be suitably blanked off.
g)
The cabinet shall be fitted with an external M12 earthing stud with a nut,
lock nut and a serrated washer.
h)
The door of the cabinet shall be fitted with a robust fastening arrangement
that is capable of being secured by a padlock that has a shackle of 8 mm
diameter.
i)
The cabinet shall be easily removable for workshop repair purposes.
8.2 Electronic control equipment
8.3
The controls shall not suffer any damage if one or more poles of the circuit
breaker fail to respond to either a trip or a close command.
8.4 Electronic modules shall perform continuous diagnostic monitoring and shall
contain hardware and software watchdog checking.
9.0
Protection characteristics
9.1
General
9.2
The ratio of drop-off current to pick-up current shall be at least 95 % for all
protection functions.
The E/F and SEF functions shall be equipped with harmonic filtering to prevent
operation when harmonics are present in the primary residual earth currents. A
low pass filter with:
a) 2nd harmonic rejection > 6 1; and
b) 3rd harmonic rejection > 50
1 shall be supplied. Both the
SEF function and its filter shall be described in the tender
documentation
All protection functions, i.e. over-current (O/C), earth fault (E/F) and sensitive
earth fault (SEF) shall have elements with characteristics that comply with IEC
255.
The sequence of trip and auto-reclose characteristics for O/C, E/F and SEF shall
be programmable to enable:
a) the selection of any combination of the available elements for each trip in
the trip-and-reclose sequence; and
b)
separate trip-and-reclose sequences for O/C, E/F and SEF.
In case of IDMTL protection elements the AR shall preferably be provided with a
disc reset timer that simulates the resetting functionality of an upstream
electromechanical induction disc relay by implementing a disc reset timer.
The length of the time delay shall preferably be settable to be able to simulate
the upstream device (settable between 5s and 20 s), however, if a fixed time
delay is provided it should be between 4s and 5s.
A zone sequence co-ordination (ZSC) feature shall be provided to ensure tripclose sequence co-ordination for combinations of rapid and delayed
protection operations applied to series ars. ZSC functionality shall be such
that:
9.3
9.4
9.5
9.6
9.7
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Technical Specification
a) an AR senses the presence of an over-current or earth fault, as well as the
clearance of that fault by another device and proceeds to the next
protection operation in its own sequence; and
b) it proceeds in its sequence of rapid protection operations only, allowing the
full number of delayed operations to be executed for in-zone conditions.
9.8 Loss of Phase (LOP) protection shall be provided to ensure the protection
functionality of AR as below:
a) AR should trip with no auto-reclose in case if there is a loss of voltage on one
or two phases on the upstream part of the line. Loss of supply on all three
phases shall not generate the protection trip.
b) Facility to turn LOP ON or OFF without affecting other protection functions of
the device. Pass-word or other form of access control shall be provided
c) The parameters of configuration of LOP shall include the voltage level (phase
to ground) and time of loss of supply on one or two phases. The voltage level
shall be configurable from 5000 to 19000 Volts (for 33KV) and 5000 to 9000
(for 11KV) with steps not greater then 250 V. Time range shall be configurable
from 1 to 60 sec with steps not greater then 1 sec.
9.9 The information about LOP operation in case of the protection trip shall be
recorded accordingly with indication of the phase(s) causing the trip of AR. The
information about LOP operation shall be easily assessable.
d) Rapid protection operation shall be possible by selecting a fast curve or
instantaneous protection element.
Co-ordination of the fast curves or instantaneous protection elements between
two devices in series shall be possible either by selecting suitable curves from a
family or by addition of a selectable time increment, typically 0,05s to 3s, in 0,05s
steps, or any other acceptable solution.
9.10 Long protection operating times associated with fault levels marginally above the
pick-up setting of the IDMTL protection element shall be avoided by the
provision of a Low Set Definite Time element with the following features:
a) it shall be possible to enable or disable the element. When enabled it shall
be active simultaneously as an overlay with all selected elements;
b) the element shall have the same pick-up current setting as the IDMTL
element; and
c) the time delay shall be selectable from 2s to 10s, in 1s steps. The time
delay shall be independent of any curve manipulation.
9.11 A High Set Instantaneous element with a selectable time delay shall be provided,
with the following features:
a) it shall be possible to enable or disable the element. When enabled it
shall be active simultaneously as an overlay with all selected elements;
b) circuit-breaker lock-out as a result of an operation due to the High Set
Instantaneous element shall be selectable;
c) the pick-up setting range of this element shall be at least 100 % to 1500
% of the over-current setting and shall be independent of any curve
manipulation; and
d) the time delay shall be selectable from instantaneous to 1s, in 0,05 s
steps. The time delay shall be independent of any curve manipulation.
9.12 A cold load pick-up (CLP) feature shall be provided that allows user selectable
modification of protection element characteristics under conditions of system
energization. The CLP function may be provided in one of the following two
ways:
a) The instantaneous O/C element and the Low Set Definite Time O/C
element could be blocked for the CLP time duration; and
b) The pick-up current setting of the IDMTL O/C element and the Low Set
Definite Time O/C element may be modified with a settable factor to
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Technical Specification
increase the pick-up current of these elements for the CLP duration.
The instantaneous O/C element should be blocked for this time. This is
the preferred method.
The CLP function shall have the following characteristics:
i. the CLP function shall not in any way interfere with any of the other
functions'/elements' pick-up current settings except as mentioned above;
ii. the CLP functionality shall be such that the active duration of the CLP is
selectable from 0 min to 20 min in 1 min steps; and
iii.
the modification factor should be settable from 1 to 2 in steps of 0,1.
9.13 Earth fault function
9.14 The earth fault setting range shall detect primary earth fault currents down to
20 A.
9.15 Delayed protection operation shall be possible by selecting an IDMTL element
with NI, VI or El curve, or a definite time protection element with time delay from
0.05s to 10s, in 0,05s steps.
9.16 Rapid protection operation shall be possible by selecting a fast curve or
instantaneous protection element.
Co-ordination of the fast curves or instantaneous protection elements between
two devices in series shall be possible either by selecting suitable curves from
a family or by addition of a selectable time increment, typically 0.05s to 3s, in
0.05s steps, or any other acceptable solution.
9.17
A High Set Instantaneous element with a selectable time delay shall be
provided with the following features:
a) it shall be possible to enable or disable the element. When enabled it shall
be active simultaneously as an overlay with all selected elements;
b) circuit-breaker lockout as a result of an operation due to the High Set
Instantaneous element shall be selectable;
c) he pick-up setting range of this element shall be at least 100 % to 1500 %
of the earth fault setting and shall be independent of any curve
manipulation; and
d) he time delay shall be selectable from 0,05s to 1s, in 05s steps. The time
delay shall be independent of any curve manipulation.
9.18 Sensitive earth fault (SEF) function
9.19 A primary earth fault current of 4A to 20A in steps not exceeding 1A shall be
detectable.
9.20 Delayed protection operation shall be possible by selecting a definite time
protection element with time delay from 3s to 25s, in 1s steps.
10.0 Auto-reclose operation parameters
10.1
The number of sequential trips to reach lockout shall be selectable to be either
1,2,3 or 4.
10.2
Reset times shall ideally be separately selectable for SEF and the combination
of over-current and earth fault functions. The reset time shall be selectable
from 5s to 120s in 1s steps.
10.3 Dead times shall ideally be separately selectable for SEF and the combination of
over-current and earth fault functions. The dead time between each successive reclosure shall be independently selectable from instantaneous
to 5s for the first reclosure and from a minimum of 2s up to a maximum of
120s for subsequent reclosures.
10.4 A close instruction initiated locally or remotely during a dead time shall result in
lockout if the fault is still present upon closure.
11.0 Statistical measurement functions
11.1 The characteristics of the statistical measurement functions shall be as
follows
11.2 Measurement shall be done with three-phase-4-wire method.
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Technical Specification
11.3 Quantities to be measured / calculated with class 0.5 accuracy are:
a) r.m.s. phase-to-phase and phase-to-neutral voltage of all three phases:
b) r.m.s current per phase
c) three phase active power in kW
d) three phase reactive power in kvars
e) total three-phase active energy in kWh
f) Power factor
g) Maximum demand
h) Harmonic analysis
i) Wave form capture
j) Fault stimulator
11.4 The real power energy, reactive energy and apparent energy measurement
should be cumulative. While maximum demand measurement shall be
integrated with respect to time. With selectable time integration periods of
5 min, 15 min, 30 min or 60 min. The data buffer shall work on the FIFO
principle and a minimum size for the data buffer shall store values for 4
months.
11.5 The voltage factor of the voltage transformers shall be a minimum of 1.9 for 8
hours.
11.6 CB and Control element shall have the facilities to record the number and
duration of outages. The information shall be assessable locally or remotely
using SCADA system. The following parameters shall be recorded:
a) Cumulative total number of outages
b) Cumulative total outage duration
c) Time and duration of each outage
12.0 Local control and indication:
12.1 The local control and indication shall be as given in Table-1:
Table-1- Minimum specification of local controls ad indications:
Item
Features
Remarks
Local control
Local/Remote
2 position key switchable
(See note 1)
Circuit-breaker open
(see note 3)
Circuit-breaker close
Secure control
ARC ON/OFF
Secure control
SEF ON/OFF
Secure or toggled control
Secure or toggled control
Local indication
Local/Remote
(see note 3)
(See note 1)
Circuit-breaker open
Circuit-breaker close
Circuit-breaker lock-out
ARC ON/OFF
SEF ON/OFF
Protection operation
See 12.7
Controller not healthy
(see note 2)
SF , Alarm
See 12.9
AC fail
DC abnormal
See 17.7
DC fail
Charger fail
Local Analog indication
(See note 1)


r.m.s phase-to-phase
to neutral voltage of all
three phases
r.m.s
current
per
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Technical Specification




phase
three phase active
power in KW three
phase reactive power
in kvars
total
three-phase
active energy in kWh
Power factor
Maximum demand
NOTES:
Note 1: The local control and the local indication features on the control panel shall be
labeled as presented in column 2, where applicable. The type of switch used for local
control shall not allow for a conflict to exist between the switch position and the function
status.
Note 2: The Controller not healthy indication shall indicate the control equipment not
healthy (watchdog) function operated. It shall not operate during the normal pole
mounted switch operating cycle. This indication should remain active until the unhealthy
state that initiated it returns to normal.
Note 3: The three-position switch (labeled as below) shall allow the AR controller to be
set in the following modes:
Remote: In this mode a local operator can trip the AR and change the mode.
A remote operator can trip or close the AR and change configuration
parameters. All reporting functions are active.
Local: In this mode a local operator can trip and close the AR and change
configuration parameters. All reporting functions are active.
12.2 All local controls and indications shall be accessible in adverse weather
condition.
12.3 The AR shall be provided with external levers to permit manual operation, using
an insulated operating stick, to open, close, lock-out and reset the AR from
ground level . Where these operations can be performed at the control
cabinet, it shall only be necessary to provide a mechanical means to open
and lockout the circuit breaker using an insulated operating stick.
12.4 The AR status shall be clearly visible from ground level. ―Opened‖ shall be
indicated with a green ―O‖. ―Closed‖ shall be indicated by a red ―I‖. Alternative
indications shall be subject to approval by the purchaser.
12.5 Pressure relief facilities shall be provided to enable the AR to withstand safely
the effects of excessive pressure rise due to an internal fault.
12.6 Malfunction of the AR shall not pose a safety hazard to the operator due to the
recoil or backlash of items such as external operating rods, ranks and levers.
12.7 Easily available (i.e maximum of one keystroke) local indication of protection
operation shall be provided for at least the last operation of the AR. The
function, phase involved and the current magnitude shall be indicated.
12.8 Switches used for local control shall offer the type of control described in table 1
i.e. secure or toggled control. Electronic keypad controls shall offer ‗quick key‘
(maximum of one keystroke) access to the controls in table1 if not
implemented with switches
12.9 ARs using SF, as an arc extinguishing/Insulating medium shall:
a) Provide a low gas pressure indication at a gas pressure that enables
safe operation of the AR
b) Prevent closing of the AR after it has opened under the abovedescribed condition
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Technical Specification
c) Be provided with a method of inhibiting any operation of the AR in the
event of the gas pressure dropping below a safe pressure.
13.0 Remote control and indication
13.1 The remote controls and indication shall be as given in table 2
Table 2- Minimum specification of remote controls and indications
1
2
3
Item
Features
Remarks
Remote control
Circuit-breaker open
Secure control
Circuit-breaker close
Secure control
ARC On
Secure control
ARC OFF
Secure control
SEF ON
Secure control
SEF OFF
Secure control
Remote indication Local/Remote
(See note 2)
(See note 3)
Circuit-breaker open
Circuit-breaker close
ARC On
ARC OFF
SEF ON
SEF OFF
IDMTL O/C Trip
Low Set DTL O/C Trip
Rapid E/F Trip
High Set E/F Trip
SEF Trip
ARC
(see note 4)
Controller not healthy
(see note 1)
SF, Alarm
See 8.9
AC fail
DC abnormal
DC fail
See 17.7
Charger fail
Analog indication
 r.m.s phase-to-phase and phase to
(See note 3)
neutral voltage of all three phases
 r.m.s current per phase
 three phase active power in KW
 three phase reactive power in kvars
total three-phase active energy in kWh
 Power factor
 Maximum demand
Note 1: The Controller not healthy indication shall indicate the control equipment not
healthy (watchdog) function operated. It shall not operate during the normal pole
mounted switch operating cycle. This indication should remain active until the unhealthy
state that initiated it returns to normal.
Note 2: The two-position switch (labeled as below) shall allow the AR controller to be
set in the following modes:
Remote: In this mode a local operator can trip the AR and change the mode. A remote
operator can trip or close the AR and change configuration parameters. All reporting
functions are active.
Local: In this mode a local operator can trip and close the AR and change configuration
parameters. Only monitoring functions are available to remote operators. The local and
remote positions shall be indicated separately.
Note 3: The ARC indication shall give alarm with any ARC attempt.
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Technical Specification
14.0 Local Engineering
14.1 The AR controller shall contain a real time clock (with leap year support) that can be set
both locally and remotely. It shall be possible to synchronise the clock with the control
center SCADA using ant of the time synchronising standards (IEC-101/IEC-104 or
SNMP protocol.
14.2 A facility for selecting all the protection, operating and communications
characteristics shall be locally available in the control cabinet. Optional
password protection against unauthorized changes shall be available.
14.3 Non-Volatile memory storage shall be sized to store the following minimum
data:
All operating , protection and communications parameters.
a) An event record containing at least 3000 events (a protection event is
defined as all operations in a sequence until successful sequence reset or
lockout). The actual number available shall be stated in the tender
documentation.
14.4 Refer to clause 11.4
Maximum demand information Maximum demand shall have the facilities to
be configured for weekly or monthly demand.
14.5 A pointer shall be provided to indicate up to where the data was last read. This
will enable regular uploading of the data without re-loading of previously read
data.
14.6 All events shall be time and date stamped with a resolution of at least loms
relative to the onboard real time clock.
15.0 Tele-control requirements
15.1
The AR controller shall detect and report disconnection of the control cable between the
controller and AR.
15.2
It shall be possible to operate AR, change the active protection group, turn AutoRecloser capabilities ON/OFF and turn E/F and SEF ON/OFF remotely using
the protocol specified in 16.6 This functionality shall be subject to the
limitations of the selected protocol. Details shall be provided in the tender
documentation.
Communications
16.0
16.1 Communication Overview
16.1.1 Technical Requirement for Unmanned Substation Communication.
16.1.2 A local control room in the substation shall have all the controls from local PC
connected to
a) All VCB Control Cubicles having RTUs, Datalogger and Numerical relays
over IEC 104 Protocol
b) All meters (TVMs) should be with DLMS protocolover IEC 104 through
suitable Data Concentrator to conver Modbus port on meters to IEC 104.
c) RTCC panel with modbus port through suitable Data Concentrator to
convert Modbus to IEC 104.
(Note : As per the norms of PFC for R APDRP, all the base line
information of the substation shall be available to the divisional
staff on a Web based tool through internet including Meter Data,
Feeder state and Tap position etc. This will be independent of the
Local or Remote PC. The communication media Modems/routers
etc. shall be made available by the employer when the remote
access function will be utilized. Until then web access on the local
PC shall be demonstrated and commissioned.)
16.1.3 The proposed substation will be connected in future to the remote control station
with SCADA/DMS and all other software tools for the relay configuration,
meter data reading etc . The hardware & software supplied should be
complete in all respects regardless of the location of the PC. When employer
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Technical Specification
decides to implement remote control, this PC shall be shifted to the remote
control center. In such situation, employer will provide only the Modems/other
Communication media with Ethernet port only at each end.
16.1.4 The bidder is responsible for the compatibility of the equipment installed for
future communication with SCADA For any communication problem that may
arise in future connectivity with SCADA, the bidder is fully responsible to make
SCADA communication operative at free of cost.
16.1.5 The bidder is to supply, install, testing & commissioning including training, of
Base computer system along with software for remote control & data
collection from 33/11 KV s/s and its analysis and Possibility to Integrate the
same with a State-Of-The-Art latest SCADA for substations in future.
16.1.6 The entire sub station shall be linked to the remote control & Monitoring station
through a single communication tunnel using GPRS Routers/any other TCP/IP
based network communication media. The s/s will be ready to be hooked to
the SCADA / EMS / DMS Software in future
16.1.7 For the Local & Remote control, monitoring and adjustments software solutions
shall be provided to carryout following tasks as minimum
o ON/OFF Operations
o Change the protection and control settings
o Up-Load the Event / Data and Demand Log
o Monitor Contact wear and Breaker health
o Monitor VCB Battery and Battery Charger
o Communications settings
o Apply Work-Tags for maintenance
o Call-out configuration (In the event of pre-programmed alarm for call-out,
the device calls back the remote station to log the alarm)
o Send messages to the concerned field staff, in case of a call-out, by
means of SMS, Voice Call, E-Mail etc. (Depending on the local resources
available, GSM Service, LAN Administrator etc.)
16.1.8 Event Logging, configured History & Demand Reports
The system is capable of logging very comprehensive data in three different
categories
a) Event Logging
This log should have all the events observed by the device including
ON/OFF operation, Local commands, protection element pick-up and trip,
change of settings, Aux supply, fault level (Interrupted current valus)
Battery low etc.
b) Demand Logging
Should upload from the devices all records of weekly and monthly
demand, which can be uploaded by the software from any remote location
and used for analysis of load behavior on each feeder including the total
no of outages and duration of outages
c) Configured History
Should be able to up-load recorded user defined parameters periodically
at user defined frequency ie. 15/30/60 min. This data can be up-loaded
from local or remote software
d) Alarms / Call-outs
There are several type of alarms, that can be configured to initiate an
emergency call-out. If any of the user defined alarm occurs in any of the
substation feeders, the device immediately calls up the Remote Control
Center which in turn initiates a alert system by sending SMS messages,
Pre-recorded Voice Messages and E-Mails etc. to user configured
locations
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Technical Specification
e) Provision for GPRS Routers with built-in Modbus/IEC Gateways for data
transmission, connecting cords/cables, antenna etc. shall be kept. The
utility in its discretion may also ask for commissioning and
training/handholding, troubleshooting from the supplier
f) Computer System
The firm will also offer a Xeon Server and a node of the good quality
suitable computer system (IBM, HP or Dell make) with latest
configurations
g) Specification of Server
a.
Intel Xeon processor (Dual CPU) Upgradeable
b.
3.2 GHz or higher speed
c.
2 MB or higher L2 ECC Cache
d.
Ultra fast Throughput with 800 MHz FSB
e.
2 GB of DDR2 RAM operating at 400 MHz or higher expendable up
to 16GB
f.
Server works/Intel server class chipset
g.
3x73 GB Ultra Wide SCSI-III Disk(15000rpm) Hot Swap
h.
Dual Channel Ultra-III SCSI Controller (320MBPS) with RAID(0,1,5)
having 128MB RAM
i.
Minimum 5 PCI/PCI-X Slot
j.
Auto-sensing full duplex 10/100/1000 MBPS Ethernet Card
k.
Minimum 6 Hot Swap 1.0‖ drive bays & two 5.25‖ bays free
l.
DVD Writer
m.
17‖ LCD Color Monitor
n.
1.44MB FDD
o.
PS/2 104Keys Keyboard
p.
Server Management features
q.
Server Configuration and Software Loading Facility
r.
Windows 2000/2003 Server
s.
UPS 1 KVA battery with 1 hrs backup
t.
GSM Modem for SMS
u.
Multimedia Speakers for alarm annunciation
h) Specification of Laptop
a)
HP/Compac/Acer
b)
Windows XP
c)
Intel Core 2 Duo, 60 GB HDD, 1 GB RAM, DVD R/W
d)
Internal Modem
The firm shall also offer Computer room furniture (two computer desks &
Six chairs) of reputed make and ACs of standard make to be installed, at
Central Stations.
16.2 As a minimum, following independent communication ports will be provided,
that allow for simultaneous operation
1. RS 232 (Configurable for Modbus, DNP3, IEC 101
2. RS 485 (Configurable for Modbus, DNP3, IEC 101
3. Ethernet.(Configurable for IEC 104)
4. USB Port for Local connection of Laptop PC
16.3 To upload the non-volatile data to and from a personal computer. The
requirements of the personal computer shall be stated in the tender
documentation.
16.4 To interface to remote communications equipment (e.g. GSM / CDMA / GPRS /
PSTN modems, radio-modems and Fiber Optic Modems).
16.5 One of the RS-232 port shall support full asynchronous V.24 functionality.
16.6 The protocol to be supported by the AR controller for remote communications
shall be as follows:
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Technical Specification
a) Support of IEC 870-5-101 & IEC 870-5-104 protocol for Remote SCADA
b) MODBUS protocol over RS 485 to communicate with the External
Numerical Relays/Energy meters/RTCC Panels
The communication interface should be designed in such a way that the
RTU can communicate both local remote station as well as SCADA. The
controller should include on board RTU and a radio power supply user
programmable between 5-15 V dc and rated for 3 A continuous, or 5 A
for 30 seconds with a 20 % duty cycle.
17.0 Power supplies
17.1
The AR system shall provide power for the electronics, operation of the AR and
operation of the communications equipment (e.g. radio or GSM-modem).
17.2
Primary supply: Preference will be given to the ability to obtain primary power
directly from the HV power system requiring no additional primary supply
connection.
Test supply: The AR shall accept an external AC 230 V 50 Hz supply.
Auxiliary supply: An auxiliary supply with the following minimum characteristics
shall be provided
17.3
17.4
17.5
17.6
17.7
17.8
18.0
18.1
One battery and constant voltage charger with current limiting shall be part of the
AR. Battery standby time shall not be less than 24 h, allowing for ten AR
operations and a Transmit: Receive: Standby duty cycle of 5:5:90 from a 5 W
output ratio. The battery shall recharge to 80 % of its capacity in a maximum of
15 h. The total number of circuit-breaker operations under the above
communications scenario shall be at least 10 AR operations preventing closing if
the battery will not have enough stored energy to open the circuit- breaker for a
protection trip condition. Details will be stated in the tender documentation.
Batteries shall be disconnected at the manufacturer's specified minimum voltage.
Battery Low' indication shall be available locally and remotely and shall include a
battery test. The indication of "Battery Low" status shall allow for a further ten
AR operations.
The minimum battery life expectancy shall be 5 years. Details of the guaranteed
life expectancy of the battery shall be stated in the tender documentation.
Maintenance and commissioning
All the communications equipment shall be easily accessible in the control
cabinet. Wiring of "communications links in the control cabinet shall permit the
connection of a temporary protocol-Monitor. It shall be possible to perform
secondary injection testing while the AR is communicating with the center.
It shall be Possible to disconnect the AR circuit breaker and connect a simulated
breaker to the control cabinet for testing purposes.
18.2
The AR shall not malfunction while the radio is transmitting via an antenna in
close proximity and the control cabinet door is open.
18.3 Provision shall be made in the control cabinet for individually isolating the power
supply to/from the following:
a)
battery;
b)
battery charger;
c)
radio; and
d)
primary supply to the control cabinet electronics.
19.0 Rating plate
Each AR shall bear a rating plate of an intrinsically corrosion-resistant material,
indelibly marked with the sea-level rating for which the equipment has been type
tested. The rating plate shall be indelibly marked with:
a.
the manufacturer's name;
b.
the equipment type designation and serial number of the ar;
c.
the mass, in kilograms;
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Technical Specification
d.
the date of manufacture;
e.
the voltage transformer ratio, class and burden.
auxiliary supply voltage (if applicable); and
20.0 Additional information
The following shall be submitted with the tender.
20.1 Circuit breaker details
20.2
20.3
20.4
20.5
20.6
20.7
20.8
20.9
20.10
20.11
20.12
20.13
20.14
20.15
20.16
20.17
21.0
a)
manufacturer;
b)
type designation;
c)
place of manufacture;
d) short circuit breaking capacity; 3s 1s
e)
asymmetrical breaking current;
f)
peak making current; and
g)
critical current (maximum instantaneous peak).
A schematic-wiring diagram of the AR offered.
A general-arrangement drawing of the AR offered.
Details of the maintenance and operating equipment and procedures needed
and a detailed parts list of the various components.
A description of the AR operation, with instruction and maintenance manuals,
including maintenance schedules, protection characteristics, communications
facilities, the method of applying settings to relays and controls, together with
any software required and the cost thereof. The software requirements shall be
stated in the tender documentation.
Details and the cost of any available portable calibration and diagnostic test set
that may be used to perform the functionality described in clause 18.1, 18.2 and
18.3. Details of the test set shall be given in the tender document.
A list of recommended spares and tools, quoting the prices of each item and its
availability.
If protection setting changes are accomplished by resistors, electronic cards or
modules or computer programs, the price and range of such items. The method
of changing protection settings shall be stated in the tender documentation.
Details of technical back-up facilities available. These details shall be stated in
the tender documentation.
Details of the class, ratio(s) and burden of the protection current transformer and
voltage transformer, if supplied, shall be stated in the tender documentation.
The supplier shall include the following details of measurement current
transformers (not internal to the AR) that can be supplied with the AR. The
following details shall be provided:
a)
available ratio(s) and accuracy class;
b)
method of fitting; and
c)
effect on creepage distance and BIL
Where applicable details of the low gas pressure alarm/lock-out philosophy;
Details of AR service history:
a) how many in service, where and for what period; and
b) contact names and numbers.
Details of LV trip/close coil if available as an option
Power requirements for a close operation
The maximum achievable separation between the control unit and the circuit
breaker.
Full details of the protocol implementation and the complete point database.
TESTS
21.1 Type tests
a) The AR shall have been type tested in accordance with, and found to comply
with, the requirements of either IEC 60056 or ANSI/IEEE C37.60-1981 for the
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Technical Specification
following, and the appropriate values shall be stated in the tender
documentation:
b) Interrupting performance (automatic operation).
c) Interrupting performance (manual operation).
d) Operating duty.
e) Making current.
f) Minimum tripping current.
g) Insulation (dielectric tests).
h) Radio interference voltage.
i) Temperature rise.
j) Mechanical operations.
k) Control equipment surge withstand capability.
21.2 The control cabinet and associated electronics shall have been type tested in
accordance with UNIPEDE NORM (SPEC) 13 (1995): Automation and Control
Apparatus for Generating Stations and Substations: Electromagnetic
Compatibility Immunity Requirements. The environment shall be considered as
failing in the HV substation category, according to NORM (SPEC)13.
21.3 Test records (on identical equipment) in the form of validated copies of test
certificates issued by a recognized testing authority shall be submitted with the
tender documentation.
21.4 Routine tests
Routine tests, as required in the relevant standards, shall be carried out as a
normal requirement of the contract and, unless otherwise agreed upon, shall be
witnessed by the purchaser or by his appointed representative. No additional
charge shall be levied for such tests or for the production or presentation of
documentation related to routine tests.
Duplicate copies of routine test certificates shall be supplied together with the
equipment when the latter is delivered to the final destination stated in the order.
22.0 PACKING/DOCUMENTATION
22.1
Packing
All equipment shall be carefully packed to prevent damage or deterioration
during normal transportation, handling and storage.
Each container shall bear the following information on the outside of the
container:
a) The address of the destination
b) The gross mass, in kilograms
c) The name of the manufacturer
d) The purchaser's order number and port of destination
23.0 Documentation
Each AR shall be supplied complete with the documentation specified in Items
as per clause 20.1 20.2 . 20.3 and 20.4, together with the routine test certificates
specified in clause 21.4.
24.0 SPECIAL TOOLS AND TACKLES
24.1
The Bidder shall furnish a list of any special tools and tackles required for maintenance
and operation purposes with recommended quantities for each substation.
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Technical Specification
2.14
1.0
TECHNICAL SPECIFICATION OF 33 KV & 11KV SELF
POWERED AUTO RECLOSER
SCOPE
The specification covers the design, manufacturing, testing, supply, installation,
testing and commissioning of 33/11kV Un-manned substation made with outdoor
pole mounted auto-recloser that have programmable protection features and
integrated remote operation capability and that are intended for distribution
networks at nominal A.C. voltages of 36/12 kV.
2.0
APPLICABLE STANDARDS
The following standards contain provisions that, through reference in the text,
constitute requirements of this specification at the time of publication the
revisions indicated were valid. All standards are subject to review and parties to
purchasing agreements based on this specification are encouraged to
investigate the possibility of applying the most recent revisions of the standards
listed below.
ANSI/IEEE C37.60-1981: Requirements for overhead, pad mounted, dry vault,
and submersible automatic circuit reclosers and fault interrupters for AC
systems (RI993)
IEC 60255, Electrical relays
IEC 60056:1987, High-voltage alternating-current circuit breakers. Amendment
No. 1:1 992.
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code).
UNIPEDE NORM (SPEC) 13 (1995): Automation and Control Apparatus for
Generating Stations and Substations: Electromagnetic Compatibility Immunity
Requirements.
2.1 CLIMATIC CONDITIONS
The Substation shall be suitable for satisfactorily working under the following
climatic conditions: Max. Ambient Temperature
Min. Ambient Temperature
Max. Relative Humidity
Min. Relative Humidity
Altitude
550 C
20 C
100 %
56 %
Below 1000 meters above mean
sea level.
The switch Switchgears and Auto-reclosers used shall be suitably designed and
treated for normal life and satisfactory operation under the hot and hazardous
tropical climate conditions and shall be dust and vermin proof. All interior and
exterior ferrous surfaces of auto-reclosers and control cabinets shall be
manufactured from marine grade stainless steel. All support structures and
associated bolts and nuts with these parts, shall be hot-dip galvanized.
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Technical Specification
3.0
TECHNICAL DATA SHEET FOR AUTO RECLOSER
Sl.
No.
34
Particulars
35
No of poles
36
37
38
39
Service
Rated System Voltage
Highest System Voltage
System earthing
40
41
45
46
Rated Voltage of AR
kV
Rated Continuous Current
Amps
c) For lines
d) For Transformers
Rated Frequency
Hz
Rated Short Circuit breaking
kA RMS
current ( I )
- 3secs – symmetrical
Rated Short Circuit making current
kA
PEAK
Interrupting medium
Insulation medium
47
48
49
50
Closing mechanism
Opening mechanism
Mounting type
Enclosure
51
52
Duty cycle
53
Insulation level
54
i) Power Frequency with Stand
kV RMS
Voltage
ii) Impulse withstand Voltage
kV Peak
Minimum clearance between
mm
phases
Minimum clearance between phase
to earth
42
43
44
55
56
Unit
Type
Minimum Creepage Distance
(Total)
Operating mechanism:
kV
kV
Data for
33kV AR
SF6
Data for
11kV AR
Solid
3
(3 Phase Ganged
Unit)
3
(3 Phase
Ganged Unit)
Outdoor
33
38
Solidly earthed
system
36
Outdoor
11
15.5
Solidly earthed
system
12
800
400
50
16
630
630
50
12.5
2.5*I
2.5*I
Vacuum
SF6 /Solid Dielectric
LV Solenoid
Springs
Single pole
316 grade
stainless steel
Vacuum
Solid dielectric
LV Solenoid
Springs
Single pole
316 grade
stainless steel
O-1strt-CO-2ndrt-CO-O-1strt-CO-2ndrt-CO3rd
3rd
rt-CO
rt-CO
CO
CO
mm
70
60
170
400
110
375
400
295
1100
780
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Technical Specification
Sl. Particulars
No.
a) Type
Unit
Data for
Data for
33kV AR
11kV AR
Solenoid-Spring Solenoid-Spring
.c) Rated voltage of Shunt trip coil
& operating range
V. DC
110[50% - 110%]
d) Rated voltage of Closing coil &
operating range
e) No. of trip coils
f) No. of closing coils
g) Nos of expandable auxiliary I/O
contacts & contact rating
(Required for transformer &
Incomer AR)
V. DC 110 [80% - 110%]
110 [50% 110%]
110 [80% 110%]
No
2 per AR
2 per AR
No
1 per AR
1 per AR
Nos
12 I/P+8 O/P 12 I/P+8 I/P (per
AMPS
(per AR)
CB)
10 A at 240V AC 10 A at 240V AC
& 10A at 110V DC & 10A at 110V
DC
h) Minimum thickness of sheet steel mm
3
3
for control cabinet
i) Enclosure Protection
IP55
IP55
57
Reclosing
Three Phase
Three Phase
auto reclosing
auto reclosing
58
Support structure
Galvanised
Galvanised
(Painted / Galvanised)
59
All other parts (Painted /
Synthetic enamel
Synthetic
Galvanised)
shade
enamel shade
631 of IS5
631 of IS5
(125 microns)
(125 microns)
60
61
62
Minimum size of control wiring
(Copper)
Protection
a) For transformer
b) For line
63
Measurement
Sq. mm
2.5
Numeric O/C, E/F, SEF,
relay Differential, OTI,
WTI, PRV,
Buchholz, OSR
with Backup
-doScheme
O/C, E/F, SEF
2.5
O/C, E/F, SEF
Differential,
REF, with
Backup
Scheme
O/C, E/F, SEF
Digital Real time current,
Real time
voltage, PF
current, voltage,
PF
4.0
DEFINITIONS AND ABBREVIATIONS
4.1
Auto-recloser (AR): A mechanical switching device that, after opening, closes
automatically after a predetermined time. Several reclosures could occur before
lockout.
4.2
Cold load pick-up (CLP) feature: A feature that allows modification of the overcurrent protection characteristics in order to prevent relay maloperation under
conditions of system energisation.
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Technical Specification
4.3
Dead time: The time between the instant that the current is interrupted by the
AR and the instant the contact of the AR closes as a result of an automatic
reclose operation. [IEC 50-448-04-09]
4.4
Definite time lag (DTL) protection element: A protection element with a
settable time delay that is constant above the pick-up current setting.
4.5
Delayed protection operation: The protection functionality enabling delayed
circuit-breaker operation, whether this is due to an IDMTL or DTL protection
element.
4.6
Disc reset time: The time required for the disc of an electromechanical IDMTL
protection relay to turn back to its original position after it has turned to the
position where a protection operation was initiated.
4.7
Effectively earthed system: An earthed system in which the healthy phase
power frequency phase-to-earth over voltages associated with earth faults are
limited to 80% of the highest phase-to-phase voltage of the system.
4.8
Fast curve protection element: A family of curves with operating times
approximately constant (slightly inverse) relative to the multiple of pick-up
setting.
4.9
Instantaneous protection element: An element with no intentional time delay
active above a pre-determined pick-up current setting.
4.10 Inverse definite minimum time (IDMT) protection element: A protection
element the minimum operating time of which is adjustable and is inversely
proportional to the fault current.
4.11 Pole-mounted remote terminal unit (PMRTU): A remote terminal unit that is
designed for pole mounting and that operates specific pole-mounted equipment
remotely.
4.12 Rapid protection operation: The protection functionality enabling rapid circuitbreaker operation, whether this is due to an instantaneous, fast curve, or a
definite time delay protection element with relatively short definite time delay.
4.13 Reset time: The time duration after a circuit-breaker close operation for which
the measured currents are below a fault detecting level. On the expiry of this
time the protection sequence resets.
4.14 Secure control: A single mechanically non-latching switch that effects one state
of a control function only. An example of which is either a non-latching switch or
two separate push buttons that effect one state of a control function only in each
position. If a control is activated repeatedly it only effects that state and does not
change the state of the control.
4.15 Sensitive earth fault (SEF) relay: A relay that is sensitive to very low earth fault
currents and in which the operating settings are for current magnitude and
definite time delay.
4.16 Supervisory: Remote control and indications of an AR or a PMRTU by means
of a telecommunications link.
4.17 Toggled control: A single mechanically non-latching switch/push-button that
enables a single control function on the first operation of the switch/push-button
and disables the function on the second operation of the same switch/push
button.
4.18 Zone sequence co-ordination (ZSC): The feature that allows protection
devices to maintain sequence co-ordination for combinations of rapid and
delayed protection operations.
5.0
Mounting
5.1
5.2
The AR shall be suitable for single pole mounting.
Adequately rated lifting eyes shall be provided and they shall be designed to
allow the completely assembled AR (surge arresters fitted) to be lifted without
recourse to a sling spreader. The diameter of the eyes shall be a minimum of
30mm.
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Technical Specification
5.3
Suitable mounting brackets for surge arresters shall be provided on the line side
and on the load side of the AR, adjacent to the bushings.
5.4
The AR shall be fitted with an external M12 earthing stud, complete with a nut,
lock nut and spring washer.
5.5
The AR shall have laser cut markings on each bushings marked U1 V1 W1 for
the normal line side and U2 V2 W2 for normal load side.
5.6
A detailed drawing of the single pole AR mounting arrangement with surge
arresters fitted shall be provided. The minimum phase-to-earth clearances shall
be as per relevant IS and is to be indicated on the drawing.
5.7
The mass of the mounting hardware, the AR and the control cabinet and cable
shall be stated in the tender documentation.
6.0
Bushings
6.1 Terminals
c)
For 33KV AR, the preferred arrangement for bushing is a fully insulated
bushing arrangement achieved by using cyclo aliphatic epoxy resign
bushings and silicone rubber bushing boots together with 3 meters 185
mm2, single core, XLPE insulated aluminum water blocked cable tails to
provide a fully insulated bushing arrangement.
d)
For 11 KV AR, the preferred arrangement for connection to overhead
conductor is using crimp lugs with holes.
6.2 Material
The following bushing materials are acceptable:
d)
Outdoor Cyclo aliphatic epoxy resin and/or Silicone rubber
e)
Porcelain bushings and EPDM rubber are not acceptable.
f)
Minimum acceptable creepage is 1100 mm for 33 KV AR and 780 mm for
11KV AR..
7.0
Finish
c)
All interior and exterior ferrous surfaces of auto-reclosers and control
cabinets shall be manufactured from 316 marine grade stainless steel.
All support structures and associated bolts and nuts with these parts, shall
be hot-dip galvanized.
d)
Suitable precautions shall be implemented to prevent corrosion due to the
use of dissimilar materials.
8.0
Control equipment
8.1 Control cabinet
j)
k)
l)
m)
n)
Cabinets that house equipment for protection and control shall be mounted
independently of the AR.
Suitable ultraviolet-resistant cable, shall be provided to connect the AR to
the control cabinet.
It shall be possible to disconnect the cable at the AR while the AR is
connected to the power system, without causing damage or mal-operation:
care shall be taken that CTs are not open circuited. A robust, multi-pin
weatherproof connector shall be supplied. The female part of the
connector shall be mounted on the AR and the male part shall be mounted
on the cable. Preference will be given to products supplying connectors at
both the AR and the control cabinet.
Cabinets shall be adequately sealed and dust protected and shall be
internally treated to prevent moisture condensation. The degree of
protection shall be IP 55.
The supplier shall ensure that the equipment housed in the control cabinet
can withstand the heating effect of direct solar radiation without causing
failure and/or mal-operation. Details shall be provided in the tender
documentation.
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Technical Specification
o)
The cabinet shall make provision for bottom entry of three cables. This
shall be done with a pre-punched suitable sized diameter holes. The holes
shall be suitably blanked off.
p)
The cabinet shall be fitted with an external M12 earthing stud with a nut,
lock nut and a serrated washer.
q)
The door of the cabinet shall be fitted with a robust fastening arrangement
that is capable of being secured by a padlock that has a shackle of 8 mm
diameter.
r)
The cabinet shall be easily removable for workshop repair purposes.
8.2 Electronic control equipment
8.3
The controls shall not suffer any damage if one or more poles of the circuit
breaker fail to respond to either a trip or a close command.
8.4 Electronic modules shall perform continuous diagnostic monitoring and shall
contain hardware and software watchdog checking.
9.0
Protection characteristics
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
General
The ratio of drop-off current to pick-up current shall be at least 95 % for all
protection functions.
The E/F and SEF functions shall be equipped with harmonic filtering to prevent
operation when harmonics are present in the primary residual earth currents. A
low pass filter with:
c) 2nd harmonic rejection > 6 1; and
d) 3rd harmonic rejection > 50
1 shall be supplied. Both the
SEF function and its filter shall be described in the tender
documentation
All protection functions, i.e. over-current (O/C), earth fault (E/F) and sensitive
earth fault (SEF) shall have elements with characteristics that comply with IEC
255.
The sequence of trip and auto-reclose characteristics for O/C, E/F and SEF shall
be programmable to enable:
b) the selection of any combination of the available elements for each trip in
the trip-and-reclose sequence; and
b)
separate trip-and-reclose sequences for O/C, E/F and SEF.
In case of IDMTL protection elements the AR shall preferably be provided with a
disc reset timer that simulates the resetting functionality of an upstream
electromechanical induction disc relay by implementing a disc reset timer.
The length of the time delay shall preferably be settable to be able to simulate
the upstream device (settable between 5s and 20 s), however, if a fixed time
delay is provided it should be between 4s and 5s.
A zone sequence co-ordination (ZSC) feature shall be provided to ensure tripclose sequence co-ordination for combinations of rapid and delayed
protection operations applied to series ars. ZSC functionality shall be such
that:
c) an AR senses the presence of an over-current or earth fault, as well as the
clearance of that fault by another device and proceeds to the next
protection operation in its own sequence; and
d) it proceeds in its sequence of rapid protection operations only, allowing the
full number of delayed operations to be executed for in-zone conditions.
Loss of Phase (LOP) protection shall be provided to ensure the protection
functionality of AR as below:
e) AR should trip with no auto-reclose in case if there is a loss of voltage on one
or two phases on the upstream part of the line. Loss of supply on all three
phases shall not generate the protection trip.
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Technical Specification
f)Facility to turn LOP ON or OFF without affecting other protection functions of the
device. Pass-word or other form of access control shall be provided
g) The parameters of configuration of LOP shall include the voltage level (phase
to ground) and time of loss of supply on one or two phases. The voltage level
shall be configurable from 5000 to 19000 Volts (for 33KV) and 5000 to 9000
(for 11KV) with steps not greater then 250 V. Time range shall be configurable
from 1 to 60 sec with steps not greater then 1 sec.
9.9 The information about LOP operation in case of the protection trip shall be
recorded accordingly with indication of the phase(s) causing the trip of AR. The
information about LOP operation shall be easily assessable.
h) Rapid protection operation shall be possible by selecting a fast curve or
instantaneous protection element.
Co-ordination of the fast curves or instantaneous protection elements between
two devices in series shall be possible either by selecting suitable curves from a
family or by addition of a selectable time increment, typically 0,05s to 3s, in 0,05s
steps, or any other acceptable solution.
9.10 Long protection operating times associated with fault levels marginally above the
pick-up setting of the IDMTL protection element shall be avoided by the
provision of a Low Set Definite Time element with the following features:
d) it shall be possible to enable or disable the element. When enabled it shall
be active simultaneously as an overlay with all selected elements;
e) the element shall have the same pick-up current setting as the IDMTL
element; and
f) the time delay shall be selectable from 2s to 10s, in 1s steps. The time
delay shall be independent of any curve manipulation.
9.11 A High Set Instantaneous element with a selectable time delay shall be provided,
with the following features:
e) it shall be possible to enable or disable the element. When enabled it
shall be active simultaneously as an overlay with all selected elements;
f) circuit-breaker lock-out as a result of an operation due to the High Set
Instantaneous element shall be selectable;
g) the pick-up setting range of this element shall be at least 100 % to 1500
% of the over-current setting and shall be independent of any curve
manipulation; and
h) the time delay shall be selectable from instantaneous to 1s, in 0,05 s
steps. The time delay shall be independent of any curve manipulation.
9.12 A cold load pick-up (CLP) feature shall be provided that allows user selectable
modification of protection element characteristics under conditions of system
energization. The CLP function may be provided in one of the following two
ways:
c) The instantaneous O/C element and the Low Set Definite Time O/C
element could be blocked for the CLP time duration; and
d) The pick-up current setting of the IDMTL O/C element and the Low Set
Definite Time O/C element may be modified with a settable factor to
increase the pick-up current of these elements for the CLP duration.
The instantaneous O/C element should be blocked for this time. This is
the preferred method.
The CLP function shall have the following characteristics:
iv. the CLP function shall not in any way interfere with any of the other
functions'/elements' pick-up current settings except as mentioned above;
v. the CLP functionality shall be such that the active duration of the CLP is
selectable from 0 min to 20 min in 1 min steps; and
vi.
the modification factor should be settable from 1 to 2 in steps of 0,1.
9.13 Earth fault function
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Technical Specification
9.14 The earth fault setting range shall detect primary earth fault currents down to
20 A.
9.15 Delayed protection operation shall be possible by selecting an IDMTL element
with NI, VI or El curve, or a definite time protection element with time delay from
0.05s to 10s, in 0,05s steps.
9.16 Rapid protection operation shall be possible by selecting a fast curve or
instantaneous protection element.
Co-ordination of the fast curves or instantaneous protection elements between
two devices in series shall be possible either by selecting suitable curves from
a family or by addition of a selectable time increment, typically 0.05s to 3s, in
0.05s steps, or any other acceptable solution.
9.17
A High Set Instantaneous element with a selectable time delay shall be
provided with the following features:
e) it shall be possible to enable or disable the element. When enabled it shall
be active simultaneously as an overlay with all selected elements;
f) circuit-breaker lockout as a result of an operation due to the High Set
Instantaneous element shall be selectable;
g) he pick-up setting range of this element shall be at least 100 % to 1500 %
of the earth fault setting and shall be independent of any curve
manipulation; and
h) he time delay shall be selectable from 0,05s to 1s, in 05s steps. The time
delay shall be independent of any curve manipulation.
9.18 Sensitive earth fault (SEF) function
9.19 A primary earth fault current of 4A to 20A in steps not exceeding 1A shall be
detectable.
9.20 Delayed protection operation shall be possible by selecting a definite time
protection element with time delay from 3s to 25s, in 1s steps.
10.0 Auto-reclose operation parameters
10.1
The number of sequential trips to reach lockout shall be selectable to be either
1,2,3 or 4.
10.2
Reset times shall ideally be separately selectable for SEF and the combination
of over-current and earth fault functions. The reset time shall be selectable
from 5s to 120s in 1s steps.
10.3 Dead times shall ideally be separately selectable for SEF and the combination of
over-current and earth fault functions. The dead time between each successive reclosure shall be independently selectable from instantaneous
to 5s for the first reclosure and from a minimum of 2s up to a maximum of
120s for subsequent reclosures.
10.4 A close instruction initiated locally or remotely during a dead time shall result in
lockout if the fault is still present upon closure.
11.0 Statistical measurement functions
11.1 The characteristics of the statistical measurement functions shall be as
follows
11.2 Measurement shall be done with three-phase-4-wire method.
11.3 Quantities to be measured / calculated with class 0.5 accuracy are:
k) r.m.s. phase-to-phase and phase-to-neutral voltage of all three phases:
l) r.m.s current per phase
m) three phase active power in kW
n) three phase reactive power in kvars
o) total three-phase active energy in kWh
p) Power factor
q) Maximum demand
r) Harmonic analysis
s) Wave form capture
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Technical Specification
t) Fault stimulator
11.4 The real power energy, reactive energy and apparent energy measurement
should be cumulative. While maximum demand measurement shall be
integrated with respect to time. With selectable time integration periods of
5 min, 15 min, 30 min or 60 min. The data buffer shall work on the FIFO
principle and a minimum size for the data buffer shall store values for 4
months.
11.5 The voltage factor of the voltage transformers shall be a minimum of 1.9 for 8
hours.
11.6 CB and Control element shall have the facilities to record the number and
duration of outages. The information shall be assessable locally or remotely
using SCADA system. The following parameters shall be recorded:
d) Cumulative total number of outages
e) Cumulative total outage duration
f) Time and duration of each outage
12.0 Local control and indication:
12.1 The local control and indication shall be as given in Table-1:
Table-1- Minimum specification of local controls ad indications:
Item
Features
Remarks
Local control
Local/Remote
2 position key switchable
(See note 1)
Circuit-breaker open
(see note 3)
Circuit-breaker close
Secure control
ARC ON/OFF
Secure control
SEF ON/OFF
Secure or toggled control
Secure or toggled control
Local indication
Local/Remote
(see note 3)
(See note 1)
Circuit-breaker open
Circuit-breaker close
Circuit-breaker lock-out
ARC ON/OFF
SEF ON/OFF
Protection operation
See 12.7
Controller not healthy
(see note 2)
SF , Alarm
See 12.9
AC fail
DC abnormal
See 17.7
DC fail
Charger fail
Local Analog indication
(See note 1)






r.m.s phase-to-phase
to neutral voltage of all
three phases
r.m.s
current
per
phase
three phase active
power in KW three
phase reactive power
in kvars
total
three-phase
active energy in kWh
Power factor
Maximum demand
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Technical Specification
NOTES:
Note 1: The local control and the local indication features on the control panel shall be
labeled as presented in column 2, where applicable. The type of switch used for local
control shall not allow for a conflict to exist between the switch position and the function
status.
Note 2: The Controller not healthy indication shall indicate the control equipment not
healthy (watchdog) function operated. It shall not operate during the normal pole
mounted switch operating cycle. This indication should remain active until the unhealthy
state that initiated it returns to normal.
Note 3: The three-position switch (labeled as below) shall allow the AR controller to be
set in the following modes:
Remote: In this mode a local operator can trip the AR and change the mode.
A remote operator can trip or close the AR and change configuration
parameters. All reporting functions are active.
Local: In this mode a local operator can trip and close the AR and change
configuration parameters. All reporting functions are active.
12.2 All local controls and indications shall be accessible in adverse weather
condition.
12.3 The AR shall be provided with external levers to permit manual operation, using
an insulated operating stick, to open, close, lock-out and reset the AR from
ground level . Where these operations can be performed at the control
cabinet, it shall only be necessary to provide a mechanical means to open
and lockout the circuit breaker using an insulated operating stick.
12.4 The AR status shall be clearly visible from ground level. ―Opened‖ shall be
indicated with a green ―O‖. ―Closed‖ shall be indicated by a red ―I‖. Alternative
indications shall be subject to approval by the purchaser.
12.5 Pressure relief facilities shall be provided to enable the AR to withstand safely
the effects of excessive pressure rise due to an internal fault.
12.6 Malfunction of the AR shall not pose a safety hazard to the operator due to the
recoil or backlash of items such as external operating rods, ranks and levers.
12.7 Easily available (i.e maximum of one keystroke) local indication of protection
operation shall be provided for at least the last operation of the AR. The
function, phase involved and the current magnitude shall be indicated.
12.8 Switches used for local control shall offer the type of control described in table 1
i.e. secure or toggled control. Electronic keypad controls shall offer ‗quick key‘
(maximum of one keystroke) access to the controls in table1 if not
implemented with switches
12.9 ARs using SF, as an arc extinguishing/Insulating medium shall:
d) Provide a low gas pressure indication at a gas pressure that enables
safe operation of the AR
e) Prevent closing of the AR after it has opened under the abovedescribed condition
f) Be provided with a method of inhibiting any operation of the AR in the
event of the gas pressure dropping below a safe pressure.
12.10 Event Logging, configured History & Demand Reports
The system is capable of logging very comprehensive data in three different
categories
i)
Event Logging
This log should have all the events observed by the device including
ON/OFF operation, Local commands, protection element pick-up and trip,
change of settings, Aux supply, fault level (Interrupted current valus)
Battery low etc.
j)
Demand Logging
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Technical Specification
Should upload from the devices all records of weekly and monthly
demand, and used for analysis of load behavior on each feeder including
the total no of outages and duration of outages
13.0 Power supplies
13.1
13.2
13.3
13.4
14.0
14.1
Auxiliary supply for closing, tripping and normal functioning of the VCB must be derived
from a 48 volts dc, sealed-maintenance-free, valve regulated lead acid (VRLA)
battery, provided in outdoor control panel. The battery should be charged through the
charger circuit provided in the control panel. The charger input shall be derived from the
secondary of the potential transformer mounted on the same pole or from any other
auxiliary source within the range 85 to 265 volts ac or dc.
AC input auxiliary power supply interface with filter unit for impulse noise protection
48 volts rechargeable sealed-maintenance-free battery to provide uninterruptible dc
auxiliary power supply for numeric data processing, VCB numeric control & monitoring
and to the communication modem (when provided). Battery must have A-H capacity
rating suitable to provide back-up supply up-to 48 hours after loss of ac input auxiliary
supply (without communication). Battery should have an average life expectancy of
around 5 years.
A thermal sensor should continuously monitor the healthiness of the battery and
any battery unhealthy condition must be recorded as a malfunction event. The
battery shutdown capacity, ampere-hour capacity, RTU shutdown level / supply
voltage, should all be programmable through the recloser control module
Maintenance and commissioning
All the communications equipment shall be easily accessible in the control
cabinet. Wiring of "communications links in the control cabinet shall permit the
connection of a temporary protocol-Monitor. It shall be possible to perform
secondary injection testing while the AR is communicating with the center.
It shall be Possible to disconnect the AR circuit breaker and connect a simulated
breaker to the control cabinet for testing purposes.
14.2
The AR shall not malfunction while the radio is transmitting via an antenna in
close proximity and the control cabinet door is open.
14.3 Provision shall be made in the control cabinet for individually isolating the power
supply to/from the following:
e)
battery;
f)
battery charger;
g)
radio; and
h)
primary supply to the control cabinet electronics.
15.0 Rating plate
Each AR shall bear a rating plate of an intrinsically corrosion-resistant material,
indelibly marked with the sea-level rating for which the equipment has been type
tested. The rating plate shall be indelibly marked with:
f. the manufacturer's name;
g.
the equipment type designation and serial number of the ar;
h.
the mass, in kilograms;
i. the date of manufacture;
j. the voltage transformer ratio, class and burden.
auxiliary supply voltage (if applicable); and
16.0 Additional information
The following shall be submitted with the tender.
16.1 Circuit breaker details
h)
manufacturer;
i)
type designation;
j)
place of manufacture;
k) short circuit breaking capacity; 3s 1s
l)
asymmetrical breaking current;
m)
peak making current; and
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Technical Specification
n)
critical current (maximum instantaneous peak).
16.2 A schematic-wiring diagram of the AR offered.
16.3 A general-arrangement drawing of the AR offered.
16.4 Details of the maintenance and operating equipment and procedures needed
and a detailed parts list of the various components.
16.5 A description of the AR operation, with instruction and maintenance manuals,
including maintenance schedules, protection characteristics, communications
facilities, the method of applying settings to relays and controls, together with
any software required and the cost thereof. The software requirements shall be
stated in the tender documentation.
16.6 Details and the cost of any available portable calibration and diagnostic test set
that may be used to perform the functionality described in clause 14.1, 14.2 and
14.3. Details of the test set shall be given in the tender document.
16.7 A list of recommended spares and tools, quoting the prices of each item and its
availability.
16.8 If protection setting changes are accomplished by resistors, electronic cards or
modules or computer programs, the price and range of such items. The method
of changing protection settings shall be stated in the tender documentation.
16.9 Details of technical back-up facilities available. These details shall be stated in
the tender documentation.
16.10 Details of the class, ratio(s) and burden of the protection current transformer and
voltage transformer, if supplied, shall be stated in the tender documentation.
16.11 The supplier shall include the following details of measurement current
transformers (not internal to the AR) that can be supplied with the AR. The
following details shall be provided:
d)
available ratio(s) and accuracy class;
16.12
16.13
16.14
16.15
16.16
16.17
17.0
e)
method of fitting; and
f)
effect on creepage distance and BIL
Where applicable details of the low gas pressure alarm/lock-out philosophy;
Details of AR service history:
c) how many in service, where and for what period; and
d) contact names and numbers.
Details of LV trip/close coil if available as an option
Power requirements for a close operation
The maximum achievable separation between the control unit and the circuit
breaker.
Full details of the protocol implementation and the complete point database.
TESTS
17.1 Type tests
l) The AR shall have been type tested in accordance with, and found to comply
with, the requirements of either IEC 60056 or ANSI/IEEE C37.60-1981 for the
following, and the appropriate values shall be stated in the tender
documentation:
m)Interrupting performance (automatic operation).
n) Interrupting performance (manual operation).
o) Operating duty.
p) Making current.
q) Minimum tripping current.
r) Insulation (dielectric tests).
s) Radio interference voltage.
t) Temperature rise.
u) Mechanical operations.
v) Control equipment surge withstand capability.
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Technical Specification
17.2 The control cabinet and associated electronics shall have been type tested in
accordance with UNIPEDE NORM (SPEC) 13 (1995): Automation and Control
Apparatus for Generating Stations and Substations: Electromagnetic
Compatibility Immunity Requirements. The environment shall be considered as
failing in the HV substation category, according to NORM (SPEC)13.
17.3 Test records (on identical equipment) in the form of validated copies of test
certificates issued by a recognized testing authority shall be submitted with the
tender documentation.
17.4 Routine tests
Routine tests, as required in the relevant standards, shall be carried out as a
normal requirement of the contract and, unless otherwise agreed upon, shall be
witnessed by the purchaser or by his appointed representative. No additional
charge shall be levied for such tests or for the production or presentation of
documentation related to routine tests.
Duplicate copies of routine test certificates shall be supplied together with the
equipment when the latter is delivered to the final destination stated in the order.
18.0 PACKING/DOCUMENTATION
18.1
Packing
All equipment shall be carefully packed to prevent damage or deterioration
during normal transportation, handling and storage.
Each container shall bear the following information on the outside of the
container:
e) The address of the destination
f) The gross mass, in kilograms
g) The name of the manufacturer
h) The purchaser's order number and port of destination
19.0 Documentation
Each AR shall be supplied complete with the documentation specified in Items
as per clause 16.1, 16.2 . 16.3 and 16.4, together with the routine test certificates
specified in clause 17.4.
20.0 SPECIAL TOOLS AND TACKLES
20.1
The Bidder shall furnish a list of any special tools and tackles required for maintenance
and operation purposes with recommended quantities for each substation.
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Technical Specification
2.15 TECHNICAL SPECIFICATION OF 33 KV OUTDOOR SF6
CIRCUIT BREAKERS (AIS TYPE)
1.0 SCOPE
1.1 The intention of this Section of the Specification is to cover design, manufacture,
testing at manufacturer‟s works of 132 and 33 KV Circuit Breakers with all fittings
and accessories including mounting structures as specified hereunder.
2.0 GENERAL REQUIREMENTS
2.1 The circuit breaker shall be of three phase unit (gang operated) (or) three identical
single phase units (as said in data sheet), outdoor, single pressure puffer type. The
operating mechanism shall be electrically and mechanically trip/free with antipumping facility suitable for remote electrical closing, tripping as well as local
Operation facility as specified. The CBs are meant for installation with Transformers
& Lines.
2.2 The circuit breaker shall be so designed to withstand the effects of temperature,
wind load, short circuit conditions and other adverse conditions.
2.3 The circuit breaker shall be capable of switching transformer magnetizing currents
and shall be restrike - free.
2.4 All similar parts, particularly removable ones, shall be interchangeable with one
another.
2.5 All cable ferrules, lugs, tags, etc. required for cabling from equipment control
cabinet/operating mechanism to the central control cabinet of the breaker shall be
supplied loose as per approved schematics.
2.6 The SF6 breaker shall be designed to ensure that condensation of moisture is
controlled by proper selection of organic insulating materials having low moisture
absorbing characteristics.
2.7 The support structure of circuit breaker shall be hot dip galvanised. Sufficient
galvanising thickness shall be achieved with 615 gm/m². All other parts shall be
painted as per painting specification enclosed separately.
3.0 OPERATING MECHANISM
3.1 A power spring operated mechanism for closing and tripping shall be provided in the
breaker control cabinet. This device shall be so interlocked that while it is under
maintenance, the breaker cannot be operated from remote. A slow acting, manually
operated device shall be provided for inspection and maintenance purposes.
3.2 Circuit breaker operating mechanism shall be capable of storing energy for atleast
two complete closing and tripping operations.
3.3 Each mechanism shall have an operation counter.
3.4 The operating mechanism shall be mounted and enclosed in a weather proof,
vermin-proof, sheet steel cabinet conforming to IP: 55 degree of protection. Sheet
steel thickness shall be as specified in data sheet. The cabinet shall also house
relays, control and auxiliary equipment of each breaker and provision for terminating
all control, alarm and auxiliary circuits. It shall be provided with hinged doors with
provision for locking and removable gland plates to be drilled at site. Inspection
window shall be provided for observation of the instruments without opening the
cabinet. It shall be mounted so as to provide convenient access from ground level.
3.5 The cabinet shall be fitted with a thermostatically controlled anti-condensation
heater, a 15A, 1 phase, 5 pin socket outlet with switch and a cubicle illuminating
lamp suitable for operation on 240 V AC 50Hz supply.
3.6 Circuit breakers shall feature high repeatability of absolute closing time over a wide
range of parameters (ambient temperature, pneumatic pressure, control voltages,
etc).
3.7 Main poles shall operate simultaneously. There shall be no objectionable rebound
and the mechanism shall not require any critical adjustment. It shall be strong, rigid,
positive and fast in operation.
3.8 Disagreement circuit shall be provided which shall detect pole position discrepancy.
3.9 The design of the circuit breaker shall be such that contacts will not close
automatically upon loss of gas/ air pressure.
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Technical Specification
3.10 Closing release shall be capable of operating within the range of the rated
voltage as specified in the data sheet. Shunt trip shall operate satisfactorily under all
operating conditions of the circuit breaker up to the rated breaking capacity of the
circuit breaker with in the range of the rated voltages specified in the Data sheet.
3.11 Working parts of the mechanism shall be of corrosion resisting material.
Bearings which require grease shall be equipped with pressure type grease fittings.
Bearing pin, bolts, nuts and other parts shall be adequately pinned or locked to
prevent loosening or changing adjustment with repeated operation of the breaker.
3.12 All controls, gauges, relays, valves, hard drawn copper piping and all other
accessories as necessary shall be provided including the following:
3.13 Low pressure alarm and lock out relay with adjustable pressure setting suitable
for operation on DC system
3.14 A no-volt relay for remote indication of power failure for compressor motor/
Spring Charge motor.
3.15 As long as power is available to the motor, continuous sequence of closing and
opening operations shall be possible.
3.16 After failure of power supply to the motor, at least one open-close-open
operation of the circuit breaker shall be possible.
3.17 Motor rating shall be such that it requires only about 30 seconds for full charging
of the closing spring.
3.18 Closing action of the circuit breaker shall compress the opening spring ready for
tripping.
3.19 During closing, springs are discharged and after closing of breaker, springs shall
automatically be charged for the next operation. Facility for manual charging of
closing springs shall be provided. Mechanical interlocks shall be provided in the
operating mechanism to prevent discharging of closing springs when the breaker is
already in the closed position.
4.0 OPERATING MECHANISM CONTROL
4.1 The breaker shall normally be operated by remote electrical control. Two electrically
independent trip circuit including two trip coils per pole shall be provided. However,
provision shall be made for local electrical control. For this purpose a local/remote
selector switch, close and trip control switch/push button shall be provided in the
breaker central control cabinet.
4.2 The trip coils shall be suitable for trip circuit supervision during both open and close
position of the breaker. Necessary terminals shall be provided in the central control
cabinet of the circuit breaker by the Supplier.
4.3 The auxiliary switch of the breaker shall be positively driven by the breaker
operating rod.
4.4 A conveniently located manual tripping lever or button shall also be provided for
local tripping of the breaker and simultaneously opening the reclosing circuit. A local
manual closing device which can be easily operated by one man standing on the
ground shall also be provided for maintenance purpose. Direction of motion of
handle shall be clearly marked.
4.5 When the spring get fully charged either through motor or hand cranking, the
spring charging motor and the hand cranking device should get disengaged
mechanically from the charged spring and this should not be depended upon
only the limit switch.
5.0 SF6 GAS SYSTEM
5.1 SF6 gas shall serve as an arc-quenching medium during opening/closing operation
and as an insulating medium between open contacts of the circuit breaker.
5.2 The circuit breaker shall be single pressure type. The design and construction of the
circuit breaker shall be such that there is a minimum possibility of gas leakage and
entry of moisture. There should not be any condensation of SF6 gas on the internal
insulating surfaces of the circuit breaker..
5.3 All gasketted surfaces shall be smooth, straight and reinforced, if necessary, to
minimise distortion and to make a tight seal, the operating rod connecting the
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Technical Specification
5.4
5.5
5.6
5.7
operating mechanism to the arc chamber (SF6 media) shall have adequate seals.
The SF6 gas leakage should not exceed 1% per year
In the interrupter assembly there shall be an absorbing product box to minimise the
effect of SF6 decomposition products and moisture. The material used in the
construction of the circuit breakers shall be such as fully compatible with SF6 gas
decomposition products.
Each pole shall form an enclosure filled with SF6 gas independent of two other
poles and the SF6 density of each pole shall be monitored. For CBs of voltage class
of 36 kV, a common SF6 scheme/density monitor shall be acceptable.
The dial type SF6 density monitor shall be adequately temperature compensated to
model the pressure changes due to variations in ambient temperature within the
body of circuit breaker as a whole. The density monitor shall have graduated scale
and shall meet the following requirements:
It shall be possible to dismantle the density monitor for checking/replacement
without draining the SF6 gas by providing suitable interlocked non return valve
coupling.
6.0 BUSHINGS AND INSULATORS
6.1 Bushings and Insulators shall be of Porcelain, Solid core type. Porcelain used for
the manufacture of bushings and insulators shall be homogeneous, free from
defects, cavities and other flaws or imperfections that might affect the mechanical or
dielectric quality and shall be thoroughly vitrified, tough and impervious to moisture.
6.2 Glazing of the porcelain shall be of uniform brown colour, free from blisters, burns
and other similar defects. Bushings shall be designed to have sufficient mechanical
strength and rigidity for the conditions under which they will be used. All bushings of
identical ratings shall be interchangeable.
6.3 Puncture strength of bushings shall be greater than the dry flashover value. When
operating at normal voltage, there shall be no electric discharge between the
conductors and bushing which would cause corrosion or injury to conductors,
insulators or supports by the formation of substances produced by chemical action.
No radio interference shall be caused by the bushings when operating at the normal
rated voltage.
6.4 Bushings shall satisfactorily withstand the insulation level specified in data sheet.
.
7.0 FIXED AND MOVING CONTACTS
7.1 Main contacts shall have ample area and contact pressure for carrying the rated
current and the short time rated current of the breaker without excessive
temperature rise which may cause pitting or welding. Contacts shall be adjustable to
allow for wear, easily replaceable and shall have minimum moving parts and
adjustments to accomplish these results. Main contacts shall be the first to open and
the last to close so that there will be little contact burning and wear out.
7.2 Arcing contacts, if provided, shall be the first to close and the last to open and shall
be easily accessible for inspection and replacement. Tips of arcing and main
contacts shall be silver faced.
7.3 If multi-break interrupters are used, they shall be so designed and augmented that a
fairly uniform voltage distribution is developed across them.
7.4
8.0 INTERLOCKS
8.1 Key release mechanical interlocks shall be incorporated in the operating mechanism
for interlocking with the associated isolators, so that operation of the circuit breaker
is dependent on a "key-trapped" situation. In addition, electrical interlocks with
associated isolators shall be provided.
9.0 ADDITIONAL DUTY REQUIREMENTS
9.1 Circuit breakers shall be capable of clearing short line faults with the same
impedance behind the bus corresponding to the rated fault current.
9.2 Circuit breakers shall be capable of breaking 25% of rated fault current at twice
rated voltage under out of phase conditions.
9.3 The Bid shall highlight the design features provided to effectively deal with:
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Technical Specification
10.0
a) Breaking of inductive currents and capacitive currents.
b) Charging of long lines and cables.
c) Clearing developing faults within the full rating of the breaker.
d) Opening on phase opposition.
ACCESSORIES
10.1 Gas Pressure Detector
The circuit breaker shall be provided with gas pressure monitor with temperature
compensation for initiating alarm and locking the operating mechanism in the event
of abnormality. Gas pressure monitor shall be provided for each pole
individually for 33 kV Circuit Breakers.
10.2 Position Indicator
Each pole of the circuit breaker shall be provided with a position indicator.
10.3 Terminals
Each circuit breaker shall be provided with suitable terminal pads of high
conductivity aluminium alloy for connecting to the line.
10.4 Auxiliary Switches
Each circuit breaker shall be equipped with auxiliary switches with sufficient number
of contacts for control, indication and interlocking purposes. Ten normally open and
ten normally closed contacts shall be provided as spares. All contacts shall be rated
for the DC voltage specified in data sheet.
10.5 Terminal Blocks
All accessories and control devices shall be completely wired. All wirings which are
connected to external circuit shall be terminated on terminal blocks installed in the
control cabinet. The terminal blocks provided shall have twenty (20) percent spares
10.6 Operating mechanism housing shall be supplied with all required accessories
including the following:
11.0
12.0
13.0
a) Padlocks and duplicate keys.
b) Space heaters equipped with automatic thermostatic control.
c) Local/remote changeover switch.
d) Manually operated tripping push button/lever (mechanical) conveniently located
to trip all three phases simultaneously.
e) Control switches to cut off control power supplies.
f) Fuses as required.
g) Two earthing terminals.
h) Auxiliary relays required for satisfactory operation.
i) Motor contactor with thermal release
j) Provision for mechanical interlock with isolator.
SUPPORT STRUCTURES
11.1 The Circuit Breakers shall be suitable for mounting on steel structures.
11.2 The support structure shall be of steel hot dip galvanised type. The height of
support structure shall be designed to keep the bottom most live part and bottom of
insulators of circuit breakers at minimum clearance from the plinth as specified in
data sheet.
11.3 All necessary galvanised bolts, nuts and washers to complete the erection shall
be furnished including the embedded anchor bolts for securing the supporting
structure to the concrete foundations.
NAME PLATES
12.1 All equipment shall have non-corrosive name plates fix at a suitable position
indelibly mark with full particular there on in accordance with the standard adapted.
EARTHING
13.1 Two earthing pads shall be provided on each supporting structure. Each control
cabinet or terminal box mounted on the supporting structure shall also be connected
to an earthing pad. Separately mounted control cabinets shall be provided with two
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012 ………………… Assam Power Distribution Company Ltd.
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Technical Specification
14.0
15.0
16.0
earthing pads adjacent to the base of the cabinet. The earthing connection shall be
bolted type and suitable for receiving 65mm x 12mm MS strip.
TERMINAL CONNECTORS
14.1 The equipment shall be supplied with required number of terminal connectors of
approved type suitable for ACSR conductors. The type of terminal connector, size of
connector, material, and type of installation shall be approved by the Employer, as
per installation requirement while approving the equipment drawings.
TESTS
15.1 All routine tests shall be carried out in accordance with relevant IS. All
routine/acceptance tests shall be witnessed by the Employer/his authorised
representative. The tests shall include the following:
a) Routine/Acceptance Tests (all units)
i) Mechanical Operation tests
ii) Power frequency voltage withstand test (dry)
iii) Tests on auxiliary & control circuits
iv) Measurement of resistance of the main circuit.
b) Type Tests:
The bidder shall furnish type test certificates and results for the following tests
along with the bid for breaker of identical design.
i) Breaking and making capacity test
ii) Short-time current test
iii) Temperature rise tests
iv) Lightning Impulse voltage test
c) Test Certificates
Copies of routine/acceptance test certificates shall be produced with the
endorsement of the inspecting authority to the Employer before effecting
despatch. The test report shall contain the following information.
i) Complete identification data, including serial No. of the breaker.
ii) Method of application, where applied, duration and interpretation of results in
each test.
PRE-COMMISSIONING TESTS
16.1 Contractor shall carry out following tests as pre-commissioning tests. Contractor
shall also perform any additional test based on specialties of the items as per the
field instructions of the equipment Supplier or Employer without any extra cost to the
Employer. The Contractor shall arrange all instruments required for conducting
these tests along with calibration certificates and shall furnish the list of instruments
to the Employer for approval.
(a) Insulation resistance of each pole.
(b) Check adjustments, if any suggested by manufacturer.
(c) Breaker closing and opening time.
(d) Slow and Power closing operation and opening.
(e) Trip free and anti pumping operation.
(f) Minimum pick-up voltage of coils.
(g) Dynamic Contact resistance measurement.
(h) Functional checking of control circuits interlocks, tripping through protective
relays and auto reclose operation.
(i) Insulation resistance of control circuits, motor etc.
(j) Resistance of closing and tripping coils.
(k) SF6 gas leakage check.
(l) Dew Point Measurement
(m) Verification of pressure switches and gas density monitor.
(n) Checking of mechanical „CLOSE‟ interlock, wherever applicable.
(o) Testing of grading capacitor.
(p) Resistance measurement of main circuit.
(q) Checking of operating mechanisms
(r) Check for annunciations in control room.
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Technical Specification
17.0
SPECIAL TOOLS AND TACKLES
17.1 The Bidder shall furnish a list of any special tools and tackles required for
maintenance and operation purposes with recommended quantities for each
substation.
TECHNICAL DATA SHEET FOR CIRCUIT BREAKER
18.0
Sl.
No.
Particulars
Unit
Data for
1
2
Type
No of poles
SF6
3
4
5
6
Service
Rated System Voltage
Highest System Voltage
System earthing
7
8
9
kV
Amps
Hz
kA RMS
10
Rated Voltage of Breaker
Rated Continuous Current
Rated Frequency
Rated Short Circuit breaking current ( I )
- 3secs - symmetrical
11
12
Rated Short Circuit making current
Duty cycle
kA PEAK
13
14
First pole to clear factor
Opening time
i) Opening Time
2.5*I
0-0.3 Sec - CO -3
Min -CO
1.3
ms
ii) Closing Time
ms
Not exceeding 50
ms
Not exceeding 120
ms
33 kV CB
15
kV
kV
18
Insulation level
i) Power Frequency with Stand Voltage
ii) Impulse withstand Voltage
Minimum clearance between phases
Minimum clearance between phase to
earth
Minimum Ground clearance (from bottom
most live part to plinth level)
19
Minimum clearance from bottom
support insulator to plinth level
16
17
20
21
22
3
(3 Phase Ganged
Unit)
Outdoor
33
36
Solidly
earthed
system
36
1250
50
25
kV RMS
kV Peak
mm
mm
70
170
320
320
mm
4000
of mm
2500
i) Minimum Creepage Distance (Total)
mm
ii)
Minimum
Creepage
Distance mm
(Protected)
Arcing horn
Operating mechanism:
a) Type
b) Rated 3 Phase, 50Hz Voltage for Drive V
Motor
.c) Rated voltage of Shunt trip coil & V. DC
operating range
d) Rated voltage of Closing coil & V. DC
900
460
Yes
Spring Charged
415
220 or 110 [50% 110%]
220 or 132 [80% -
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Technical Specification
operating range
e) No. of trip coils
f) No. of closing coils
g) No of spare auxiliary contacts & contact
rating
No
No
Nos
AMPS
h) Minimum thickness of sheet steel for mm
control cabinet
i) Enclosure Protection
Reclosing
23
24
Support structure (Painted / Galvanised)
25
All other parts (Painted / Galvanised)
26
Minimum size of control wiring (Copper)
Sq. mm
110%]
2 per CB
1 per CB
10 N/O+10 N/C
(per CB)
10 A at 240V AC
& 2A at 220V/
110V DC
3
IP55
Three Phase auto
reclosing
Galvanised
Synthetic enamel
shade
631 of IS5
(125 microns)
2.5
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2.16 TECHNICAL SPECIFICATION FOR 33 KV CONTROL AND
RELAY PANELS FOR TRANSFORMERS & FEEDERS
1.0 SCOPE
1.1. This specification provides for design, engineering, manufacture, assembly,
shop testing, inspection and testing at works, transport to site, insurance,
storage, erection and commissioning of Control, Relay, Alarm and
Annunciation Panels for 33/11 KV, Substations.
1.2. It is not the intent to specify completely herein all details of the design and
construction of equipments. However, the equipment shall conform in all
respects to high standards of engineering, design and workmanship and
shall be capable of performing in continuous commercial operation
acceptable to the purchaser, who will interpret in a manner the meanings of
drawings and specifications and shall have the power to reject any material
which in his judgment is not in accordance therewith. The equipment offered
shall be complete with all components necessary for its effective and trouble
free operation. Such components shall be deemed to be within the scope of
Bidder's supply, irrespective of whether these are specifically brought out in
this specification and/or the commercial order or not.
1.3. It may be noted that the Control & Relay Panels must meet the following
minimum criteria. Failure to comply with the requirements may results in
rejection of the BID as non-responsive:
1.3.1. The Manufacturer must have designed, manufactured, type tested and
supplied Control 7 Relay Panels in at least two power utilities of similar
rating which are in successful operation for at least 5 (Five) years as on the
date of bid opening. Which should be substantiated by furnishing
performance report by the official of the rank of minimum DGM/SE
2.0 STANDARDS
All equipment provided under this specification shall in general conform to the latest
revision/amendment etc. of the following:
Sl No.
1
4
Standard
IS: 3231, IEC 255 Part-I to III,
BS: 89
IS: 1248; IS: 2419; BS: 89
IS-13010; IS: 722(Part-I to IX)
IEC 521; BS 3T
IS: 4237
5
IS: 375
6
7
IS: 8686, IEC-255 Part V &VI
IEC 801-4
IEC 337; IEC: 337-1; IS: 6875
8.
IS: 2516
9
10
11
IS: 4047
IS: 2208
IS: 2705; IEC-185
2
3
Title
Electrical relays for power system
protection.
Indicating instruments
Energy meters
General
requirement
of
switchgear and control gear for
voltages not exceeding 1 KV
Marking
arrangement
for
switchgear,
busbars,
main
connection & auxiliary wiring.
Specification for static protective
relays and tests
Control switches ( LV switching
devices for control and auxiliary
circuits)
MCCB sand load break switches
having a break capacity of 30
KVA rms at 415 V.
Fuse switching units
HRC fuse links
Current transformers
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Technical Specification
12
13
IS: 3156; IEC: 186
IS: 8623
14
IEC: 439
15
IS: 4237
16
IS: 2147
17
18
IS: 5028
IS: 1897
19
20
IS: 3618; IS : 6005
IS: 4064
21
22
IS: 9224 Part II
IS: 5578
23
IS: 2032
24
IEC
25
ISO
26
IS
Potential transformers
Factory built assemblies of
switchgear & control gear for
voltages upto & including 1000V
AC & 1200 V DC
Low voltage switchgear and
control gear assemblies
General
requirement
of
switchgear & control gear for
voltages not exceeding 1000V
Degree of protection provided by
enclosures for
low voltage
switchgear and control gear
Aluminium alloy bars
Copper strips for electrical
purpose
Code of practice for phosphate
Air break switches, air break
disconnectors,
air
break
disconnectors & fuse combination
units for voltages not exceeding
1000 V AC or 1200 V DC.
HRC cartridge fuses
Guide for making of insulated
conductors
Graphical symbols
Ref-abbreviations
Name and Address
Institution
Electro
Technical
Bureau. Central dale commission
Electro Technique International.
1. Rue de vermbe Geneva
Switzerland
International Organization for
standardization. Danish Board of
Standardization..Danish
Standardizating
Sruat
Aurehoeqvaj-12 DK- 2990, Heel
prup Denmark
Bureau of Indian Standard
Standards Manak Bhawan 9,
Bahadur Shah Zafar Marg, New
Delhi- 110 002, India.
2.1. Equipment meeting with the requirements of other authoritative Standards,
which ensure equal or better performance than the standards mentioned
above, shall also be considered. When the equipment offered by the Bidder
conforms to other standards, salient points of difference between standards
adopted and the standard specified in this specification shall be clearly
brought out in the relevant schedule. Four copies of such standards with
authentic translation in English shall be furnished along with the offer.
3.0 CLIMATIC CONDITIONS
3.1. The climatic and isoceraunic conditions at site under which the equipments
shall operate satisfactorily under the tropical conditions specified in this
bidding documents.
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3.2. The reference ambient temperature assumed for the purpose of this
specification are as follows:
i. Maximum ambient temperature
ii. Maximum average daily ambient temperature
iii. Maximum average yearly ambient temperature
: 40° C
: 35° C
: 30° C
4.0 PRINCIPAL PARAMETERS
4.1. The details of Current Transformer are given below:
Core
No.
1
2
3
Accuracy
Burden class Minimum knee
Purpose
point voltage as
per Formula
33 KV side Transformer CT Ratio: 200-100/5-5-5 A
5 P 20
20 VA
----O/L & E/F Protection
PS
---Min. Vk = 100 V
Transformer
Max. Im= 0.03 A differential protection
accuracy
15 VA
-----Metering
0.5,
Instrume
nt
security
factor < 5
33 KV side Feeder CTs Ratio: 400-200/5-5 A
11 KV side Transformer CT Ratio: 600-300/5-5 -2.89 A
1
2
5 P 10
PS
20 VA
----
3
Accuracy
0.5
15 VA
---Min. Vk = 200 V
Max. Im= 0.03 A
------
O/L & E/F Protection
Transformer
differential protection
Metering
11 KV side Feeder CT Ratio: 400-200/5-5 A
4.2. Breakers for HV & LV sides of transformer
HV side breaker
: VCB, Outdoor
LV (11KV ) side breaker
: Vacuum type, Indoor/Outdoor
Rating of closing coil & Trip coil : 110 V DC,
Number of auxiliary contact
: 6 N/O and 6 N/C
Both HV & LV breakers are provided with two sets of trip coils( Each set common to
all three phases)
5.0 Drawing, Manuals, Literatures etc.
5.1. The tenderer shall furnish along with his tender fully dimensioned drawings
of the equipments offered, along with illustrated and descriptive literatures,
for various component parts like relays, meters, control switches etc. to
enable the purchaser for proper evaluation of the offer. The tenders shall
also be accompanied with the schematic drawings showing protection,
indicating metering schemes etc
5.2. Soon after the award of the contract and before proceeding with the
manufacturing works, the successful tenderer shall furnish drawings in
quadruplicate which shall include but not limited to the followings for
approval of the purchaser:
i)
Principal layout drawings for the Boards showing the equipments on the
panels with dimensions. A list of the equipments mounted on each panel shall be
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Technical Specification
prepared and tabulated in the same drawings. The drawings shall also show the
constructional details, foundation details indicating foundation bolts, cable entries
etc.
ii)
Elementary control drawings and other schematics for the equipments
furnished, including protection, metering, annunciating and indicating circuit,
breaker control ,circuits etc. All wires terminals shall be clearly marked and
numbered as per general practice.
iii)
Single line and three line diagrams showing all AC and D.C power
connections and all secondary connectors for relays, meters etc.
iv)
Internal wiring diagrams of all the panels and boards giving internal wiring
connections for all the equipments in the panels. The drawings shall also clearly
indicate the connections to be made at site or to the external equipments or
between boards etc. with wires terminals marked properly.
v)
After approval of the drawings the tenderer shall furnish six copies of the
each of the final drawings along with the literatures, instruction manuals etc. for
purchaser's reference.
5.3. In addition to the above the successful bidders shall supply three sets each
of the following relevant equipments supplied to each substation:
a. All final drawings mentioned above.
b. Literature describing construction, operation, adjustment, testing, calibration,
maintenance of all protective and auxiliary relays, instruments, control switches
etc.
c. List of spare parts giving identification numbers of the parts.
6.0 GENERAL TECHNICAL REQUIREMENT
6.1. Control & Relay panels: Detailed Description
The control and relay panels shall be of Simplex type. Each Simplex panel shall consist
of a vertical front panel with equipment mounted thereon and having wiring access from
the rear. It shall have double leaf door with lift off hinges at the back for panels of width
more than 800 mm. Doors shall have handles with built-in locking facility.
7.0 Constructional Features
7.1. Panels shall be completely metal enclosed and shall be dust, moisture and
vermin proof. The enclosure shall provide a degree of protection not less
than IP-51 in accordance with IS:2147.
7.2. Panels shall be free standing, floor mounting type and shall comprise
structural frames enclosed completely with specially selected smooth
finished, cold rolled sheet steel of thickness not less than 3 mm for
weight bearing members of the panels such as bass frame, front sheet
and door frames, and 2.0 mm for sides, door top and bottom portions.
There shall be sufficient reinforcement' to provide level Surface resistance to
vibration and rigidity during transportation and installation.
7.3. All doors, removable covers and panels shall be gaskets all around with
neoprene gaskets. Ventilation louvers to be provided having screens and
filters. The screens shall be made of brass wire mesh.
7.4. Design, materials selection and workmanship shall be such as to result in
neat appearance inside and outside with no welds, rivets or bolt head
apparent from outside, with all exterior surfaces true and smooth.
7.5. All necessary anchor bolts and other materials required for foundation of
panels shall be supplied
7.6. Cable entries to the panel shall be from the bottom. The plates of the panel
shall be fitted with removable gland plates for fixing the cable glands.
Necessary number of cable glands of sizes to suit owner's external cables to
the panels shall be supplied by the bidder. Cable glands shall be screwed
type, and shall be suitable for PVC cables. Cable gland plate fitted in the
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Technical Specification
bottom of the panel shall be connected to the earthing Panel / Station
through a flexible braided copper conductor rigidly.
7.7. Relay panels of modern, modular construction would also be acceptable.
7.8. The total height of the panel shall be 2250 mm. The depth of the panel
shall be 600 mm. The panels shall have suitable width required for
mounting of all the equipments on the front panel.
7.9. The panels shall match with the existing panels in APDCL substations, the
details of which will be furnished to the successful bidder. Matching includes
height , depth of the panels, colour matching and mimic matching' and
arrangement of equipment on the front.
8.0 Mounting
8.1. All equipment on and in panels shall be mounted and completely wired to
the terminal blocks ready for external connection. The equipment on front of
panel shall be mounted flush.
8.2. Equipment shall be mounted such that removal and replacement can be
accomplished individually without interruption of service to adjacent devices
and are readily accessible without use of special tools. Terminal marking
shall be clearly visible.
8.3. The contractor shall carry out cutouts, mounting and wiring of the free issue
items supplied by others, if any which are to be mounted in this panel in
accordance with the corresponding equipment manufacturer's drawings.
Cutouts if any, provided for future mounting of equipment shall be properly
blanked off.
8.4. The center lines of switches, push buttons and indicating lamps shall be not
less than 750 mm from the bottom of the panel. The center lines of relays,
meters and recorders shall be not less than 450 mm from the bottom of the
panel.
8.5. The center lines of switches, push buttons and indicating lamps shall be
matched to give a neat and uniform appearance. Likewise the top lines of all
meters, relays and recorders etc., shall be matched.
8.6. No equipment shall be mounted on the doors.
8.7. All the equipment connections and cabling shall be designed and arranged
to minimize the risk of fire and damage which may be caused by fire.
9.0 Panel Internal Wiring and Other Accessory Equipment
9.1. Panels shall be supplied completely. with interconnecting wiring provided
between all electrical devices mounted and wired in the panels and between
the devices and terminal blocks for the devices to be connected to
equipment outside the panels. When panels are arranged to be located
adjacent to each other all inter panel wiring and connections between the
panels shall be furnished and the wiring shall be carried out internally. These
adjacent inter panel wiring shall be clearly indicated in the drawing furnished
by the contractor.
9.2. All wiring shall be carried out with 1100 V grade, single core, stranded
copper conductor wires with PVC insulation and shall be heat resistant grade
and vermin and rodent proof. The minimum size of the stranded copper
conductor used for internal wiring shall be as follows:
i) All circuits except current transformer and potential transformer circuits
one multi strand 2.5 Sq. mm per lead
ii) Current transformer circuit : one 4.0 Sq. mm per lead. The minimum
number of strands per conductor shall be three.
9.3. All internal wiring shall be securely supported, neatly arranged, readily
accessible and connected to equipment terminals and terminal blocks.
Wiring gutters and troughs shall be used for this purpose.
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9.4. Auxiliary bus wiring for AC and DC supplies, voltage transformer circuits,
annunciation circuits and other common services shall be provided near the
top of the panels running throughout the entire length of the panels.
9.5. Wire termination shall be made with solder less crimping type and tinned
copper ring type lugs which firmly grip the conductor and insulation. Insulted
sleeves shall be provided at all the wire terminations. Engraved core
identification plastic ferrules marked to correspond with panel wiring diagram
shall be fitted at both ends of each wire. Ferrules shall fit tightly on the wire
and shall not fall off when the wire is disconnected from terminal blocks
9.6. All wires directly connected to trip circuit of breaker or device shall be
distinguished by the addition or red coloured unlettered ferrule. Number 6
and 9 shall not be included for ferrule purposes.
9.7. Longitudinal troughs extending throughout the full length of the panel shall
be preferred for inter panel wiring. Interconnections to adjacent panel shall
be brought out to a separate set of terminal blocks located near the slots or
holes meant for taking the inter connecting wires. Arrangements shall permit
easy inter connections to adjacent panels at site and wires for this purposes
shall be provided by contractor looped and bunched properly inside the
panel.
9.8. The Successful bidder shall be solely responsible for the completeness and
correctness of the internal wiring and for the proper functioning of the
connected equipment.
10.0 Terminal Blocks
10.1. All internal wiring to be connected to the external equipment shall
terminate on terminal blocks preferably vertically mounted on the side of
each panel. Terminal blocks shall be 1100 V grade and have 10 amps
continuous rating ,complete with insulated barriers, stud type terminals,
washers, nuts and lock nuts. Terminal block design shall include a white
fibre markings strip with clear plastic slip-on terminal covers. Markings on the
terminal strips shall correspond to wire number and terminal numbers on the
wiring diagrams.
10.2. Terminal blocks for current transformer and voltage transformer
secondary leads shall be provided with test links and isolating facilities. Also
current transformer secondary leads shall be provided with short-circuiting
and earthing facilities.
10.3. At- least 20 % spare terminals shall be provided on each panel and these
spare terminals shall be uniformly distributed on all terminal blocks.
10.4. Unless otherwise specified. terminal blocks shall be suitable for
connecting the following conductors of purchasers cable on each side
i.
ii.
All circuits except current and potential transformer circuits : minimum of
one of 2.5 sq.mm copper.
All CT and PT circuits: minimum of two of 4.0 mm square copper.
10.5. There shall be a minimum clearance of 250 mm between the first row of
terminal blocks and associated cable gland plate. Also the clearance
between two rows of terminal blocks shall be minimum, of 150 mm.
10.6. Arrangement of the terminal block assembles and the wiring channel
within the enclosure shall be such that a row of terminal blocks is run parallel
and in close proximity along each side of wiring duct to provide for
convenient attachment of internal panel wiring. The side of the terminal block
opposite the wiring duct shall be reserved for purchaser's external cable
connection. An adjacent terminal block shall also share this fired wiring
corridor. A steel strip shall be connected between adjacent terminal block
rows at 450 mm intervals for support of incoming cables.
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Technical Specification
10.7. The number and sizes of the Purchaser's multi-core incoming cable will
be furnished to the Contractor after placement of the order. All necessary
cable terminating accessories such as gland plates, packing glands, crimp
type tinned copper lugs supporting clamps .and brackets, wiring troughs and
gutters etc., for purchaser's cable shall be included in contractor's scope of
supply.
11.0 Painting
11.1. All sheet steel work shall be phosphated, in accordance with the 18:6005
"Code of Practice for phosphating iron and steel". Oil, grease, dirt and sweat
shall be thoroughly removed by emulsion cleaning. Rust and scale shall be
removed by picking with dilute acid followed by washing with running water
rinsing with a slightly alkaline hot water and drying.
11.2. After phosphating thorough rinsing shall be carried out with clear water
followed by final rinsing with dilute dichromate solution and oven drying. The
phosphate coating shall be sealed with application of two coats of ready
mixed, stoved type zinc chromate primer. The first coat may be "flash dried"
while the second coat shall be stoved .
11.3. After application of the primer, two coats of finishing synthetic enamel
paint shall be applied, each coat followed by stoving. The second finishing
coat shall be applied after completion of tests. The exterior Colour of the
paint shall be selected by the purchaser at a later date.
11.4. Each coat of primer and finished paint shall be of a slightly different shade
to enable inspection of the painting. The powder coat paint shade should Air
Craft Grey (IS : 5) and thickness of 50-60 microns.
A small quantity of finished paint shall be supplied for minor touching up
required at site after installation of the panels.
11.5. In case the bidder proposes to follow any other established painting
procedure like electrostatic painting, the procedure shall be submitted along
with offer/bid for purchaser's review and approval.
12.0 Mimic Diagram
12.1. Coloured mimic diagram and symbols showing the exact representation of
the system shall be provided in the front of control panels.
12.2. Mimic diagram shall be made preferably of anodized aluminum or plastic
of approved fast Colour material which shall be screwed on to the panel and
can be easily cleaned. Painted overlaid mimic is also acceptable. The mimic
bus shall be 2 mm thick. The width of the mimic bus shall be 10 mm for bus
bars and 7 mm for other connections.
12.3. Mimic bus Colour will be decided by the Purchaser and shall be obtained
from the Purchaser by the successful Bidder.
12.4. When semaphore indicators are used for isolator position they shall be so
mounted in the mimic that the isolator closed position shall complete the
continuity of mimic.
12.5. Indicating lamp, one for each phase for each bus shall be provided on the
mimic to indicate bus charged condition.
13.0 Name Plates and Markings
13.1. All equipment mounted on front and rear side as well as equipment
mounted inside the panels shall be provided with individual nameplates with
equipment designation engraved. Also on the top of each panel, on front as
well as rear side, large and bold nameplates shall be provided for
circuit/feeder designation.
13.2. AlI front mounted equipment shall be also provided at the rear with
individual name plates engraved with tap numbers corresponding to the one
shown in the panel internal wiring to facilitate easy tracing of the wiring. The
nameplates shall be mounted directly by the side of the respective
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equipment in a visible manner and shall not be hidden by the equipment
wiring.
13.3. Nameplates shall be made of non-rusting metal or any other suitable
material. Nameplates shall be black with white engraving lettering. The
nameplates inscription and size of nameplates and letters shall be submitted
to the purchaser for approval.
13.4. Each instrument and meter shall be prominently marked with the quantity
measured e.g. kV, A, MW, etc. All relays and other devices shall be clearly
marked with manufacturer's name, manufacturer's type, serial number and
electrical rating data.
13.5. Each switch shall bear clear inscription, identifying its function e.g.
"BREAKER" ,"52 A‘‘, "AMMETER" etc. Similar inscriptions shall also be
provided on each device whose function is not otherwise identified. If any
switch device does not bear this inscription separate name plate giving its
function shall be provided for it. Switch shall also have clear inscription for
each position indicating e.g. "TRIP-NEUTRAL-CLOSE", "ON-OFF", "R-Y-BN:-OFF", etc.
14.0 Miscellaneous Accessories and Supporting Steel
14.1. Plug point- An AC 240 Volts, single phase, 5A, 50 HZ AC plug point shall
be provided in the interior of each cubicle with "ON-OFF" Switch for
connection of hand lamps.
14.2. Interior lighting: Each panel shall be provided with a CFL lighting fixture
rated for 240 volts, single phase, 50 HZ supply for the interior illumination of
the panel during maintenance. The fittings shall be complete with switch fuse
unit and switching of the lighting shall be controlled by the respective panel
door switch.
14.3. One DC emergency lamp is to be fitted and should be complete with
switch fuse unit.
14.4. Each control panel shall be provided with necessary arrangements for
receiving, distributing, isolating and fusing of DC and AC supplies for various
control signaling, lighting and space heater circuits. MCBs for the incoming
circuits and fuses for sub-circuits shall be provided. Selection of the main
and sub-circuit fuse rating shall be such as to ensure selective clearance of
sub-circuit faults. Potential circuit for relaying and metering shall be
protected by fuses. All fuses shall be HRC cartridge type conforming to IS :
2208 mounted on plug-in type fuse bases. All accessible live connection to
fuse bases shall be adequately shrouded. Fuses shall have operation
indicators for indicating blown fuse condition. Fuse carrier base shall have
imprints of the fuse rating and voltage.
14.5. Supporting Steel: All necessary foundation anchor bolts and other parts of
supporting and fastenings, of the panels shall be supplied by the contractor.
15.0 Earthing
15.1. All panels shall be equipped with an earth bus securely screwed. Location
of earth bus shall ensure no radiation interference for earth systems under
various switching conditions of isolators and breakers. The material and the
sizes of the bus bar shall be at least 25 x 6 mm copper flat.
15.2. When several panels are mounted adjoining each other, the earth bus
shall be made continuous and necessary connectors and clamps for this
purpose shall be included in the scope of supply of contractor. Provision
shall be made for extending the earth bus bars to future adjoining panels on
either side.
15.3. Provision shall be made on each earth bus bars of the end panels for
connecting purchaser's earthing grid. Necessary terminal clamps and
connectors for this purpose shall be included in the scope of supply of
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contractor. The wire or screens should be clearly bonded and earthed at the
gland plate.
15.4. All metallic cases of relays, instruments and panel mounted equipment
shall be connected to the earth bus preferably by independent copper wires
of size not less than 2.5 Sq.mm. The colour code of earthing wires shall be
green. Earthing wire shall be connected on terminals with suitable clamp
connectors and soldering shall not be permitted.
15.5. Looping of earth connections which would result in loss of earth
connection to other devices where the loop is broken shall not be permitted.
However, looping of earth connections between equipment to provide
alternative paths to earth bus shall be provided.
15.6. VT and CT secondary neutral or common lead shall be earthed at one
place only at the terminal blocks where they enter the panel. Such earthing
shall be made through links so that earthing may be removed from one
group without disturbing continuity of earthing system for other groups.
16.0 Metering Instruments: Instruments and Meters
16.1. All instruments, meters, recorders and transducers shall be enclosed in
dust proof, moisture resistant, black finished cases and shall be suitable for
tropical use. They shall be calibrated to read directly the primary quantities.
They shall be accurately adjusted and calibrated at works and shall have
means of calibration, check and adjustment at site. All accessories including
test switches and test plugs, where applicable shall be furnished. Their
elements shall be shock resistant and shielded from external magnetic fields.
16.2. . Ammeters:
16.2.1.
All ammeters shall be of analouge circular dial type and provided
with direct reading triple range scale. Scale value of ammeters shall be
equal to 1 to 1.3 times the rated primary current of the associated current
transformer feeding it. The rated current shall be 5.0 Amp. Accurate reading
of ammeter shall be possible at the lowest limit of 5 % of the rated current.
Accuracy class 1.0 or better as per IS: 1248
16.3. Voltmeter:
16.3.1.
All voltmeters shall be of analouge circular dial type . The
maximum scale value of voltmeters shall be 50% in excess of the primary
voltage of the associated PTs. The rated voltage of the voltmeter shall be
110 volts A.C., accuracy class 1.0 or better as per IS: 1248.
16.4. Watt meters
16.4.1.
Analouge circular dial type watt meters wherever specified shall be
3 phase, 4 wire three element type provided with direct reading scales. The
scale values of wattmeter shall be as per ratio of the measuring cores of
respective CTs and PTs. The current coils shall be rated for 5/1 ampere and
voltage coils for 110 volt continuous. The wattmeters shall be suitable for
circuits with unbalanced loads to be usually met with in commercial service.
Accuracy class will be 1.0 or better as per IS: 1248.
16.5. Energy Meters :
16.5.1.
Energy meters shall be static type conforming to IEC 687 and
suitable for bi-directional power flow. The static meter shall measure active
and reactive energy both import and export, by 3 phases 4 wire principle
suitable for ba1anced / unbalanced 3 phase load. Accuracy of meter shall.
be 0.5for active energy and 0.5 for reactive energy. THE METER SHALL
BE OF CATEGORY-A with DLMS protocol having RS 485 /232 &
Optical ports as per detail APDCL Specification. Each meter shall have
a unique identification code provided by purchaser and shall be marked
permanently on the front and also on the non-volatile memory. The voltage
monitoring of all the three voltages shall be provided.
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Technical Specification
16.5.2.
The meter shall normally operate with power drawn from VT
supplies. Power supply to the meter shall be healthy even with a single
phase VT supply. An automatic back up shall be provided by a built in life
time battery and shall not need replacement for at least ten years with a
continuous VT interruption of even two years. Date and time of VT
interruption and restoration shall be automatically stored in non-volatile
memory.
16.5.3.
The meter shall have an optical port at the front of the meter for
data collection by a hand held device. The meter shall have means to test
MWH accuracy and for connecting it to time of day tariff equipment.
16.5.4.
The meter should have optical port for local communication.
RS 232 and RS 485 port should be incorporated along with Ethernet
port.
16.5.5.
The bidder is to provide the software for meter for downloading and
up loading to base computer along with one hand held common meter
reading instrument along with software.
16.5.6.
The meter should preferably be either Secure or L & T make as
per APDCL‟s specification with DLMS protocol.For any other make
approval is to be obtained.
17.0 Relays:
17.1. All relays shall conform to the requirements of IS:3231 or other applicable
approved standards. Relays shall be suitable for flush or semi flush
mounting on the front with connections from the rear. Relays shall be
rectangular in shape and shall have dust tight, dull' black or egg shall black
enamel painted cases with transparent cover removable from the front.
17.2. All protective relays shall be in draw out or plug-in type / modular cases
with proper testing facilities. The testing facilities provided on the relays shall
be specifically stated in the bid. Necessary test plugs shall be supplied loose
and shall be included in Contractor's scope of supply. Test block and
switches shall be located immediately below each relay for testing. As an
alternative to test block and test plug arrangements the Bidder shall also
quote alternative testing facility of protective relays by providing a push
button which when pressed connects the testing equipment to the relay coils
and injects current in the coil and automatically disconnects the trip circuits
and on operation of relay gives a signal that the equipment and the circuits
are correct.
17.3. The purchaser reserves the right for accepting anyone of the above two
testing facilities. Unless otherwise specified all auxiliary relays and timers
shall be supplied in non-draw out cases/plug in type modular cases.
17.4. All AC relays shall be suitable for operation at 50 Hz AC Voltage operated
relays shall be suitable for 110 Volts VT secondaries and current operated
relays for 5 Amp CT secondaries as specified in this specification. DC
auxiliary relays and timers shall be designed for 110 V DC voltage and shall
operate satisfactorily between 70 % and 110% of rated voltage. Voltage
operated relays shall have adequate thermal capacity for continuous
operation.
17.5. The protective relays shall be suitable for efficient and reliable operation
of the protection scheme described in the specification. Necessary auxiliary
relays and timers required for interlocking schemes for multiplying of
contacts/suiting contact duties of protective relays and monitoring of control
supplies and circuits, lockout relay monitoring of circuits etc., and also
required for the complete protection schemes described in the specification
shall be provided.
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Technical Specification
17.6. All protective relays shall be provided with at least two pairs of potential
free isolated output contacts. Auxiliary relays and timers shall have pairs of
contacts as required to complete the scheme. Contacts shall be silver faced
with spring action. Relay cases shall have adequate number of terminals for
making potential free external connections to the relay coils and contacts
including spare contacts. Relay case size shall be so chosen as not to
introduce any limitations on the use of available contacts on the relay due to
in-adequacy of terminals. Paralleling of contacts, if any, shall be done at the
terminals on the casing of the relay.
17.7. All protective relays, auxiliary relays and timers except the lock out relays
and interlocking relays specified shall be provided with self-reset type
contacts. All protective relays and timers shall be provided with externally
hand reset positive action operation indicators, provided with inscription,
subject to purchaser's approval. All protective relays which do not have built
in hand reset operation indicators shall have additional auxiliary relays with
operating indicators for this purpose. Similar separate operating indicator
(auxiliary relays) shall also be provided in the trip circuits of protections
located outside the board such as bucholz relays, temperature protection,
fire protection. etc.,
17.8. Timers shall be done of the electromagnetic or solid state type. Pneumatic
timers are not acceptable. Short time delays in terms of milliseconds may be
obtained by using copper slugs on auxiliary relays. In such case it shall be
ensured that the continuous rating of the relay is not affected. Time delay in
terms of milliseconds obtained by the external capacitor resistor combination
is not acceptable.
17.9. No control relay which shall trip the power circuit breaker when the relay
is de-energized shall be employed in the circuits.
17.10. Provision shall be made for easy isolation of trip circuits of each relay for
the purpose of testing and maintenance.
17.11. All relays shall withstand a test voltage 2.5 kVrms voltage,50Hz for one
second.
17.12. Auxiliary seal-in-units provided on the protective relays shall preferably be
of shunt reinforcement type. If series relays are used the following, shall be
strictly ensured:
i. The operating time of the series seal-in-unit shall be sufficiently shorter than that
of the trip coil or trip relay in series with which it operates to ensure definite
operation of the flag indicator of the relay.
ii. Seal-in-unit shall obtain adequate current for operation when one or more relays
operate simultaneously.
iii. Impedance of the seal-in-unit shall be small enough to permit satisfactory
operation of the trip coil on trip relays when the DC supply voltage is minimum.
17.13. All protective relays and alarm relays shall be provided with one extra
isolated pair of contacts wired to terminals exclusively for purchaser's use.
17.14. For numeric relays the following requirements shall be met with :
17.14.1.
Numerical relay shall have both RS 485 and RS 232
communication ports. And ten numbers digital IO. Relay software is
required.
17.14.2.
The numerical relays shall be completely numerical with protection
elements realized using software algorithm.
17.14.3.
The relay should have high immunity to electrical and
electromagnetic interference. Relay should confirm to following mandatory
type test for safe operation of relay :
a.
b.
High frequency disturbance test as per IEC 610 – 4-1
Fast transient disturbance test as per IEC 61000 – 4-4
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Technical Specification
c.
d.
e.
18.0
Electrostatic discharge as per IEC 61000 – 4-2
Radio frequency interference as per ANSI C 37.90.2
Impulse test as per IEC 6100 – 4-3
Annunciation System:
18.1. Alarm annunciation system shall be provided for the control board by
means of visual and audible alarm in order to draw the attention of the
operator to the abnormal operating conditions or the operation of some
protective devices. The annunciation equipment shall be suitable for
operation with 110 V DC voltage.
18.2. The visual annunciation shall be provided by annunciation facia, mounted
flush on the top of the panels. The audible alarm shall be provided by alarm
buzzer and bell for trip and non-trip alarm respectively.
18.3. The annunciator fascia shall be provided with translucent plastic window
for alarm point with minimum size of 35 mm x 50 mm. The facia plates shall
be engraved in black lettering with respective inscriptions which will be
furnished to the Bidder by the purchaser.
Alarm inscriptions shall be engraved on each window in not more than three lines
and size of the let6tering shall not be less than 5 mm.
18.4. Each annunciation window shall be provided with two white lamps in
parallel to provide safety against lamp failure. Long life lamps shall be used.
The lamp circuit shall include series resistor of adequate rating. The cover
plate of the facia windows shall be flush with the panel and shall be capable
of easy removal to facilitate replacement of lamps. The transparency of
cover plates and wattage of the lamps provided in the facia windows shall be
adequate to ensure clears visibility of the inscriptions in the control room
having high illumination intensity (500 lux) from the location of the operator's
desk.
18.5. TRIP AND NONTRIP facia shall be differentiated. All TRIP facia shall
have red colour and all NONTRIP facia shall have white colour.
Sl.
No.
1
2
3
4
5
Alarm condition
Fault contact
Open
Close
Close
open
Close
Visual
Annunciation
Off
Flashing
Steady on
Steady on
On
Audible
Annunciation
Off
on
Off
Off
Off
Normal
Abnormal
Acknowledge
push
button is pressed
Reset push button is
pressed
Lamp test push button
pressed
Open
Steady on
Off
18.6. Visual and audible annunciation for the failure of DC supply to the
annunciation system shall also be provided and this annunciation shall
operate on 240 volts AC supply with separate fuses. On failure of the power
supply to the annunciation system for more than 3 seconds (adjustable
setting) an indicating lamp shall light up and a bell shall sound. A separate
push button shall be provided for cancellation of this audible alarm alone but
the indicating lamp shall remain steadily lighted till the supply to the
annunciation system is restored. The sound of the audible alarm (bell)
provided for this annunciation shall be different from the audible alarm
provided for this annunciation system.
18.7. A separate voltage check relay shall be provided to monitor the failure of
supply (240 V AC) to the scheme mentioned above. If the failure of supply
exists for more than 2 to 3 seconds, this relay shall initiate visual and audible
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Technical Specification
annunciation. The annunciation system described above shall meet the
following additional requirements.
18.8. The annunciation system shall be capable of catering to all simultaneous
signals at a time.
i) One self resetting push button shall be provided on each panel for testing in
fascia window lamps. Push buttons for testing flasher and audible alarm circuit
of annunciation supply failure· monitoring shall also be provided. These testing
circuits shall be so connected that while test is being done it shall not prevent
the registering of any new annunciation that may land during the test.
iii) One set each of the following push buttons shall be provided on each
panel.
a)
Reset push button for annunciation system;
b) Accept push button for annunciation system.
iv) The annunciation shall be repetitive type and shall be capable of registering the
fleeting signal. For fault contacts which open on a fault, it shall be possible at
site to change annunciators from "close to fault" and vice versa.
v) The annunciator shall be suitable for operation with normally open fault contacts
which close on a fault. For fault contacts which open a fault, it shall be possible
at site to change annunciators from "close to fault" and vice versa.
vi) Only electro-magnetic relay type alarm and annunciation relay schemes are
acceptable and static type annunciation schemes are not acceptable.
Contactors are not acceptable for annunciation system.
19.0
Switches
19.1. Control and Instrument switches shall be rotary operated type with
escutcheon plates clearly marked to show operating position and circuit
designation plates and suitable for flush mounting with only switch front plate
and operating handle projecting out. Handles of different shapes and
suitable inscriptions on switches aS per clause 6.8 shall be provided as on
aid switch identification.
19.2. The selection of operation handles for the different types of
switches shall be as follows:
1
2
3
4
Breaker & isolator switches
Selector switches
Instrument switches
Protection transfer switch
Pistol grip, black
Oval or knob, black
Round, knurled, black
Pistol grip, lockable & black
19.3. The control switch of breaker and isolator shall be of spring return to
neutral type. The spring return type shall be provided with target which shall
indicate the last operation of the switch. The control springs shall be strong
and robust enough to prevent inadvertent operation due to light touch. The
spring return type switch shall have spring return from close and trip
positions to "after close" and "after trip" positions respectively.
19.4. Instrument selection switches shall be of maintained contact (stay put)
type. Ammeter selection switches shall make-before-break type contacts so
as to prevent open circuiting of CT secondaries when changing the position
of the switch. They shall be of 5 position type viz R-Y-B-N-Off. Voltmeter
transfer switches for AC shall be suitable for reading all line-to-line and lineto neutral voltages for non-effectively earthed systems and for reading all
line to line voltages for effectively earthed systems .
19.5. Lockable type of switches which can be locked in particular positions shall
be provided when specified. The key locks shall be fitted on the operating
handles.
19.6. The contacts of all switches shall preferably open and close with snap
action to minimize arcing. Contacts of switches shall be spring assisted and
contact faces shall be with rivets of pure silver. Springs shall be used as
current carrying parts.
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Technical Specification
19.7. The contact combination and their operation shall be such as to give
completeness to the interlock and function of the scheme. The contact rating
of the switches shall be as follows:
Contact Rating in Amps
a) Make and carry continuously
b) Make and carry for 0.5 Sec.
c) Break
i) Resistive load
ii) Inductive load with L/R= 40
20.0
110 V DC
10
30
240 V AC
10
30
3
0.2
7
7
Indicating Lamps
20.1. Indicating lamps shall be panel mounting type with rear terminal
connections. Lamps shall be of LED type. Lamps shall have translucent
lamp covers to diffuse light coloured red, green, amber, dear white or blue as
specified. The lamp cover shall be of screwed type, un-breakable and
moulded from heat resisting material. 20% of lamps actually used on the
boards and 10% of the lamp bases of various colour actually used shall be
supplied in excess to serve as spares.
20.2. The wattage and resistance of the lamps shall be as follows:
110 V -5 to 7 W - 1000 to 2000 Ohms
21.0
22.0
20.3. Bulbs and lenses shall be interchangeable and easily replaceable from
the front of the panel. Tools, if required for replacing the bulbs and lenses
shall also be included in the scope of supply.
20.4. The indicating lamps with resistors shall withstand 120% of rated voltage
on a continuous basis.
Position Indicators
21.1. Position indicators of 'SEMAPHORE' type shall be provided when
specified as part of the mimic diagrams on panels for indicating the position
of circuit breakers, isolating/earthing switches etc. The indicator shall be
suitable for semi-flush mounting with only the front disc projecting out and
with terminal connection from the rear. Their strips shall be of the same
colour as the associated mimic.
21.2. Position indicator shall be suitable for either AC or DC operation as
specified. When the supervised object is in the closed position, the pointer of
the indicator shall take up a position in line with the mimic bus bars, and at
right angles to them when the object is in the open position. When the
supply failure to the indicator occur the pointer shall take up an intermediate
position to indicate the supply failure. The rating of the indicator shall not
exceed 2.5 W.
21.3. The position indicators shall withstand 120% of rated voltage on a
continuous basis.
Trip Circuit Supervision Relays
22.1. Trip circuit shall be supervised by means of relays. The scheme shall
continuously monitor each trip coil in both pre-close and post-close of the
breaker. The scheme shall detect. i) Failure of DC supply to each trip coil. il)
Open circuit of trip circuit wiring and iii) Failure of mechanism to complete
the tripping operation.
22.2. Also 2 Nos. indicating lamps to act in conjunction with trip circuit
supervision relays for healthy trip indication of 2 sets of trip coils shall be
supplied.
22.3. Necessary external resistors for trip circuit supervision relays shall be
supplied.
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Technical Specification
23.0 Flag Relays Shall Have
i) Hand reset flag indication
ii) Two elements
iii) Have necessary NO/NC contacts for each element/coil to meet scheme
requirements.
24.0 Detailed Description of Protections
The protection, auxiliary relay and timers and other equipment that are required to be
provided are included in the detailed equipment schedule of panels vide Annexure.-I of
this specification The detailed description of Back up protection and the associated
equipment is described below:
The setting ranges of relays given in specification are indicative. The setting ranges of
the equipment offered, if different from the ones specified, shall also be acceptable if
they met the functional requirements.
The bidder shall quote the protection equipment, meeting the following requirements.
33/11 KV, TRANSFORMER
a) Differential Protection
It shall have
i) Triple pole high speed percentage biased differential type.
ii) An operating time not more than 30 milli Secs. At 5 times operating
current setting of 20%.
iii) Three instantaneous high set over current units
iv) Second harmonic restraint feature and fifth harmonic by pass/restraint
feature and also be stable under normal over fluxing conditions.
v) an operating current setting of 20% or less,
vi) Suitable for rated current of 5A and 1 Ampere
vii) Adjustable bias setting range of 20% to 50%
viii) Two bias windings per phase
ix) Stable on heavy through faults
x) Include necessary separate interposing CTs for angle and ratio
correction or have internal features in the relay to take care of angle and ratio
correction.
xi) Shall be of numerical type.
a)
b)
c)
d)
e)
f)
b)
Over current and earth fault protection for transformer
The relay should be triple pole non-directional with IDMT characteristics. It
should either be numeric or electromagnet type, however offer for Areva make
Micom series of relay will be preferred.
c)
Auxiliary relays for transformer protection devices
Auxiliary relay required for bucholtz trip and alarm, HV winding temperature trip
& alarm, LV winding temperature trip & alarm, oil temperature alarm & trip and
low oil level alarm, PRV trip, shall be provided. Each auxiliary relay shall have 2
pairs of contacts and one hand reset flag indicators. The auxiliary relays may be
of non-draw out type
d)
Inter Tripping Relays
1 No. inter trip relay to trip HV and LV breakers of the transformer and to isolate
the transformer from supply shall be supplied. The inter trip relay shall be of
high speed and shall be provided with hand reset operation indicator and 4 NO
+ 2 N/C hand reset contacts for 33 KV breaker and 13 NO + 3 N/C hand reset
contacts for 11 KV breaker.
The protection scheme shall function as follows:
Differential relays operated: both HV, and LV breakers trip.
OIC & E/F on HV operated: both H.V and LV breakers trip.
Buchholz Relay Operated: both HV & L.V. breakers trip.
Winding temperature trip contact closed: both HV & LV. breakers
trip.
Oil temperature - alarm only.
PRV Operated: both HV & L.V. breakers trip.
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Technical Specification
24.1. Relay and Control Panels for 33 kV Feeders
Following meters, relays etc shall be provided in the feeder panel, However. any other
items which are not specifically mentioned in this specification but are required to
complete the scheme and for satisfactory operation of scheme shall also be deemed to
be included in this specification.
1)
PROTECTIVE RELAYS:
Over current relay
2 Nos
Earth fault relay
1 No
Relays for OIC and E/F protection shall
I.
be of numeric non-directional type
II.
be of triple pole type with two outer elements for O/C and the other forE/F protection.
b
III.
a)
b)
c)
d)
a)
b)
c)
d)
a)
b)
c)
d)
e)
25.0
e with IDMT characteristics with a definite minimum time of 3 sec at 10 times
settings.
IV. have a variable setting range of 50-200% for over current and 20-80% for
earch fault.
V.
be rated for 5/1 ampere
VI. include hand reset flag indicator
2)
INSTRUMENTS AND METERS
Following meters and instruments shall be provided in the panel:
One no. Ammeter Digital Type
One no. Voltmeter Digital Type
One no Watt meter of digital type
Electronic Trivector meter ( as per specification)
3)
CONTROLS
Following control switches shall be provided in the panel:
One no., three position (i.e. trip-neutral-close) breaker control switch.
One no. Ammeter- selector switch.
Push button for trip circuit healthy indication.
Selector switch for voltmeter
4)
INDICATION AND ALARMS
Following indicating arrangement shall be provided in the feeder panel:
Indicating lamps for CB ON/OFF positions
2 nos.
Indicating lamp for TRIP CIRCUIT HEALTHY CONDITION
2 No
Indicating lamp labeling Breaker Spring changed
1 No
Indicating lamp for Auto-trip indication
1 No.
Mimic diagram indicating the relevant position of the single
Line diagram of the sub-station incorporating the
Semaphore Indicators for circuit breakers
Semaphore indicator for Isolators
And for Earth switch
1 No.
2 Nos.
1 No.
AUXILIARY SUPPLY
Auxiliary supplies which shall be made available in substation are as follows:
a) A.C. supply 415 V/240 volts, 50Hz three/single phase
b) D.C. supply: 110 Volts
26.0 INSPECTION
Inspection may be carried out by the purchaser or third party nominee at any stage of
manufacture. The supplier shall grant free access to the purchaser's representative or
third party nominee at a reasonable time when the work is in progress. Inspection and
acceptance of any equipment under this specification by the purchaser shall not relieve
the supplier of his obligation of furnishing equipment in accordance with the
specification and shall not prevent subsequent rejection if the equipment is found
defective.
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Technical Specification
3.4
TECHNICAL SPECIFICATION FOR 11 kV VACUUM CIRCUIT
BREAKER (OUTDOOR).
1.0 SCOPE :1.1. This specification covers design, manufacturing, testing, of 11 KV Porcelain Clad
Vacuum Circuit Breakers complete with all accessories required for its satisfactory
operation for the Sub T transmission solidly grounded system. The Breaker shall be
used for Feeder Control/ protection in the system.
1.2. It may be noted that the 11 KV Outdoor Vacuum Circuit Breaker must meet the
following minimum criteria. Failure to comply with the requirements may results in
rejection of the BID as non-responsive:
1.2.1. The Manufacturer must have designed, manufactured, type tested and supplied
11 KV Outdoor Vacuum Circuit Breaker in at least two power utilities of similar
rating which are in successful operation for at least 5 (Five) years as on the date of
bid opening. Which should be substantiated by furnishing performance report by
the official of the rank of minimum DGM/SE
2.0 TYPE AND RATING :2.1. The circuit breaker shall be suitable for outdoor operation under the climatic
conditions as specified in Tender Specification without any protection from sun
and rain. The 11 KV circuit breakers shall have the following rating:-
SN
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
Particulars
Number of Poles
Nominal System Voltage
Highest System Voltage
Frequency
Interrupting capacity at nominal system
voltage
Rated continuous Current
Short Circuit current
Lightning Impulse Voltage
One min power frequency withstand voltage
Total break-time for any current up to the
rated breaking current
Control Circuit Voltage
Operating Duty for gang operation
Values
3
11kV
12kV
50 Hz
500MVA
630A
25kA for 3 sec
75 kVp
28kV rms
5 cycles
110Volt DC
O-0.3sec.-CO-3
CO
min-
Minimum Clearances
a) Phase to Phase
b) Phase to Earth
c) Live part to ground
Minimum Creepage distance
280mm
190mm
2750mm
300mm
2.2. The above is minimum requirement. The suppliers may offer their standard design
keeping in view the minimum requirements.
2.3. The circuit breakers shall comply with the requirements of IS:13118(1991) or IEC
62271-100 with latest amendment thereof
3.0 VACUUM INTERRUPTER
3.1. The design of the vacuum interrupter shall be such that it gives trouble free operation
under normal load and fault conditions throughout the life of the equipment. As the
efficiency of the breaker depends on the degree of vacuum inside, it has to be
ensured by the that manufacturer that the it is maintained consistently during service.
To know the residual life of vacuum interrupter, an indicator/means to indicate
status of contact erosion should be provided.
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Technical Specification
3.2. Insulating ceramic body of the interrupter should have high mechanical strength and it
should be capable of withstanding high temperature without any significant
deterioration in its mechanical and electrical properties.
3.3. The metal/alloy used for the fixed and moving contacts shall have very low resistivity
and low gas content. They should be resistant to arc erosion and the contact should
have no tendency to get cold welded under the high vacuum in the interrupter.
3.4. The interrupter design should ensure rapid de-ionization of the gap so that normal
electrical strength of the gap is restored instantaneously.
3.5. The metallic bellow or any other similar vacuum sealing arrangement should be
provided at the moving contact and should have a long fatigue life.
3.6. Vacuum interrupter is to be supplied from reputed manufacturer such BEL, CGL, ABB
or Areva.
3.7. . Manufacturer‘s catalogue of vacuum bottle, indicating all the details shall essentially
be submitted and supporting document to be submitted.
4.0 INSULATION OF THE CIRCUIT BREAKER
4.1. The insulation to ground, the insulation between open contacts and the insulation
between phases of the completely assembled circuit breaker shall be capable of
withstanding satisfactorily di-electric test voltage corresponding to specified basic
insulation level in the standard.
5.0 INSULATORS
5.1. Basic insulation level of the insulator and insulating porcelains shall be as specified
and porcelain shall be homogenous and free from cavities and other flaws. They shall
be designed to have ample insulation, mechanical strength and rigidity for satisfactory
operation under conditions specified above. All insulators of identical ratings shall be
inter-changeable. The puncture strength of the insulators shall be greater than the
flash over value.
6.0 OPERATING MECHANISM
6.1. The circuit breaker shall be designed for remote control from the control room and in
addition there shall be provision for manual operation of circuit breakers during
maintenance and for local tripping and closing by normal means.
6.2. The circuit breakers shall have operation counter and mechanical ―open‖ and ―closed‖
indicator, in addition to facilities for remote electrical indication. An operation counter
shall also be provided in the common operating mechanism. The mechanical
indicator and operation counter shall be located in a position where it shall be visible
to a man standing on the ground level with the mechanism housing doors are in
closed position.
6.3. The operating mechanism shall be of the spring charging type, by electric control
under normal operation. The mechanism shall be trip free electrically and
mechanically. Mechanism shall also be capable of performing satisfactorily, the reclosing duty cycles.
6.4. All working parts in the mechanism shall be of corrosion resistant materials and all
bearings which require greasing shall be equipped with pressured grease fittings. The
mechanism shall be strong, quick in action and removable without disturbing other
parts of the circuit breaker.
6.5. Mechanism and breaker shall be such that the failure of any spring will not prevent
tripping and will not cause tripping or closing.
6.6. Operating mechanism should be motor operated spring charged type preferably
without chain drive.
6.7. Motor for spring charging shall be suitable to perform satisfactorily for input supply
voltage of 230V AC 50 Hz with a variation of (+) 10 and (-)20 percent. A.C. motor
should have overload protection.
6.8. Provision should also be made for mounting of mechanism box at an adequate height
and gear ratios shall be so chosen that one man should be able to charge the spring,
without any additional efforts.
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Technical Specification
6.9. The mechanical arrangement should be provided to facilitate manual tripping of circuit
breaker for emergency trip under emergent condition i.e. failure of DC supply, trip coil
burnt, mechanism being defective while arc quenching media is healthy
7.0 MOTORS:
7.1. Motors shall be single phase self-starting induction motor of appropriate capacity for
satisfactory operation for the application and duty as required for driving equipment.
7.2. Motors shall be of self ventilated type having TEFC (totally enclosed fan cooled)
enclosure. Depending upon the capacity and loading conditions Bidder/manufacturer
shall design suitable grease lubricated or oil lubricated bearings for above motors.
Bearing shall be so constructed that the loss of grease and its creeping along with
shaft into motor housing is prevented. It shall also prevent dirt and water from getting
into the motor.
7.3. Continuous motor rating (name plate rating) shall be at least ten (10) percent above
the maximum load demand of the driven equipment at design duty point and the
motor shall not be overloaded at any operating point of driven equipment that will
arise in service.
7.4. Motors shall be capable of giving rated output without reduction in expected life span
when operated continuously in the system having the particulars as given in principle
parameters.
7.5. All induction motors shall be suitable for full voltage direct-on-line starting. These
shall be capable of starting and accelerating to the rated speed along with the driven
equipment without exceeding acceptable winding temperature even when supply
voltage drops down to 80% of the rated voltage.
8.0 CONTROL CUBICLE
8.1. A common control cubicle shall be provided to house electrical controls, monitoring
devices and all other accessories, except those which must be located on individual
poles. Cubicle shall be IP-55 of gasketed weather-proof construction, fabricated from
sheet steel of minimum 2.5 mm. thickness. The cubicle shall have front access door
with lock and keys. Space heater, internal illumination lamp, 3-pin 5A socket with
individual ON-OFF switches.
8.2. For local operation following shall be provided: a) LOCAL/REMOTE selector switch
b) TRIP/NORMAL/CLOSE control switches with pistol grip handle.
8.3. The control circuits shall be designed to operate on 110 DC and it shall be possible to
adopt to work on other voltages by simply changing the operating coils.
8.4. Shunt tripping coils shall be designed to operate satisfactorily within 70% to 110%
and shunt closing coil within 85% to 110% of the rated DC voltage.
8.5. AC Power supply for auxiliaries will be available at 230V single phase 50 Hz.
8.6. Necessary cable glands for the cables of the operating mechanism shall be provided.
The cables used for operation are un-armoured 2.5 sq. mm. copper control cables of
1100 V grade. Cable glands provided may therefore be suitable for 1 no. 7 core and 2
nos. 4 core unarmoured 2.5 sq. mm. copper control cable.
8.7. Circuit breaker shall be provided with trip free mechanism so that tripping instructions
could over-ride the closing instructions. An additional tripping coil shall also be
provided in the trip circuit. The second coil shall have separate tripping lever
arrangements in the mechanism, so as to avail full advantage of second trip coil. Also
the two trip coils shall have separate DC circuits, so that in the event of any short
circuit/ damage in any one of the trip coil, supply is available in the other one.
8.8. Circuit diagram of control circuit of VCB along with operating instructions (DO‘S/
DON‘T) shall be embossed on metallic plate duly laminated and the same shall be
fixed on the rear door of the control cubicle from inside.
9.0 WIRING
9.1. Wiring shall be completed in all respects to ensure proper functioning of the control,
protection, monitoring and interlocking schemes.
9.2. All wiring shall be carried out with 1100V grade PVC insulated stranded copper
conductor of 2.5 sq. mm.
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9.3. Each wire shall be identified at both ends with permanent markers bearing wire
numbers as per wiring diagram.
9.4. Wire termination shall be done with crimping type connectors with insulating sleeves.
Wires shall not be spliced between terminals.
9.5. All spare contacts of auxiliary switches etc. shall be wired up to terminal blocks in the
control cubicle.
10.0
TERMINAL BLOCKS
10.1.
Terminal blocks shall be of 1100V grade, box clamp type ELMEX 10 sq.mm or
approved equivalent. Not more than two wires shall be connected to any terminals.
Spare terminals, equal in number to 20% of active terminals, shall be provided.
10.2.
Terminal block shall be such located that it allows easy access. Wiring shall be
so arranged that individual wires of an external cable can be connected to
consecutive terminals.
11.0 TERMINAL CONNECTORS
11.1.
All circuit breakers shall be provided with 6 nos. terminal connectors suitable to
receive Wolf ACSR/AAA conductors. Clamps shall be designed adequately to take
care of any bimetallic effect. Terminal connectors shall be tested for short circuit
current capability, temperature rise.
11.2.
Terminal connector shall also meet the following requirements:
a) Terminal connectors shall be manufactured & tested as per IS:5561.
b) All castings shall be free from blow holes, surface blisters, cracks and cavities.
All sharp edges and corners shall be blurred and rounded off.
c) No part shall be less than 12 mm thick.
d) Nuts, bolts & washers used in the current path shall be stainless steel.
e) Bimetallic strips/sleeve copper alloy liner of minimum thickness of 2mm
shall be cast integral with Aluminum body.
f) All current carrying parts shall be designed and manufactured to have
minimum contact resistance.
g) Terminal connectors should be made of Aluminum Alloy and
manufactured by gravity die-casting process only. Sand die-casted
connectors are not acceptable.
h) Size of terminal connector for which the clamp is designed and also
rated current under site conditions shall be embossed/ punched on each
part of clamps, except hardware.
i) Conductor shall be tightened by at least four bolts. Conductor hold
length must not be less than 60 mm.
j) Surface of clamps to be tightened by bolts should be flat in shape, so that it
may be possible to open the nuts and bolts by normal spanners. Therefore, any
type of groove in the clamp body for fixing of nuts should be avoided.
k) Portion of clamp to hold the conductor should be flat and straight and
not zigzag in
construction at both the sides, so that heating of clamp by throttling action of
current may be avoided.
l) Space of at least 50% of diameter of nuts should be available after hole at both
the sides of conductor holding portion for better mechanical strength.
12.0 AUXILIARY CONTACTS
12.1.
Eight numbers each of auxiliary contacts both of the normally open and normally
closed types shall be provided in each circuit breaker for use in remote indication and
control scheme of the circuit breaker and for providing safety interlocking. Special
contacts for use with trip coils which permit for relative adjustment with respect to the
travel of the circuit breaker shall also be provided. Wherever required, there shall be
provision to add more auxiliary contacts at a later date, if required. All auxiliary
contacts shall be placed in a weather proof casing and current rating of the contacts
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shall be as mentioned in the bid. Provision shall be available to convert these spare
―normally-open‖ contacts to ―normally-closed‖ type and vice versa.
13.0 ACCESSORIES
13.1.
Circuit breaker shall be supplied as a complete unit with internal wiring installed
and terminated in mechanism box and equipped with the following accessories :(i) Motor operated spring charged mechanism : 1 No.
(Motor voltage - 230 V AC, 50 Hz)
(ii) Trip coil suitable for 110 V DC : 2 Nos.
(iii) Closing coil suitable for 110 V DC : 1 No.
(iv) Pistol grip C.B. Control switch having : 1 No.
Trip /normal /close position
(v) Local/remote selector switch : 1 No.
(vi) Spring Charged indicator: 1 No.
(vii) Manual operating handle for maintenance : 1 No.
(viii) Facility for manual charging of spring : 1 No.
(ix) Operation counter : 1 No.
(x) Auxiliary contacts (8 NO - 8 NC) : 1 Set
(xi) Anti pumping device suitable for 110 V DC : 1 No.
(xii) Bimetallic terminal connectors suitable for : 6 Nos.
connecting WOLF /RACCOON ACSR/AAA conductor.
(xiii) Cubicle illuminating lamp with protective : 1 No.
cage and on/off switch
(xiv) Spare terminals block : 20% of the Total active terminals
(xv) Mechanical ON/OFF Indicator : 1 No.
(xvi) MCB for both AC and DC supply : 1+1 No.
(xvii) Space heater with thermostat and : 1 No.
ON/ OFF switch
(xviii) 3-Pin 5 A socket with on/off switch : 1 Set
(xiv) Earthing terminals : 2 Nos.
(xx) Foundation Bolts : As per requirement
(xxi) Cable glands : As per requirement
13.2.
Other accessories which are not specified above, but are required for efficient
and trouble free operation of breaker, should also be provided without any extra cost.
14.0 MOUNTING OF CTs
14.1.
The offered steel structures for breakers should also have adequate strength to
accommodate 3 nos. CTs on it with provision of suitable supports from ground.
15.0 TEMPERATURE RISE
15.1.
The maximum temperature attained by any part of the equipment, when in
service at site, under continuous full load conditions, exposed to the direct rays of the
sun, shall not exceed 45˚ C above ambient temperature. The limits of temperature
rise shall be as per relevant standard.
.
16.0 TYPE TESTS
16.1.
Type test certificates for the following tests, as per IS:13118 or IEC 62271-100
with latest amendment thereof, from any of the NABL accredited Laboratory shall
invariably be furnished
a. Short circuit duties test
b. Short time withstand current and peak withstand current tests
c. Temperature rise test
d. Mechanical endurance test
e. Lightning impulse voltage withstand test
f. Power Frequency withstand voltage test (dry & wet)
g. Single Capacitor bank switching test
h. Degree of protection IP-55 as per IS:13947:93(Part-I)/IEC 60529:89
16.2.
Type test certificates must accompany drawing of type tested equipment, duly
sealed & signed by type testing authority.
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16.3.
Type tests should not have been conducted on the equipment earlier than 3
years from the date of opening of bids.
16.4.
In case of any change in design/type of breaker already type tested and the one
being offered against this specification, the Employer reserves the right to demand
repetition of some or all tests without any extra-cost at NABL accredited lab.
17.0 ACCEPTANCE AND ROUTINE TEST :17.1.
Employer shall have access at all times to the works and all other places of
manufacture where the Circuit Breakers are being manufactured and the Bidder shall
provide all facilities for unrestricted inspection of the Bidder/manufacturer‘s works,
raw materials, manufacture of all the accessories and for conducting necessary tests
as detailed herein. The Employer reserves the right to insist for witnessing
acceptance/routine testing of the bought out items. The Bidder/manufacturer shall
submit the routine test certificates of bought out items and raw material also, at the
time of routine testing of the fully assembled breaker
17.2.
No material shall be dispatched from its point of manufacture unless the material
has been satisfactorily inspected and tested.
17.3.
Bidders shall indicate the inspections and checks carried out at various stages of
manufacture of the circuit breakers. Complete record of stage inspection would be
kept by the Bidder/manufacturer and this record should be made available for
inspection by the representative of the Employer. Bidder/manufacturer should
indicate the manufacturing programme and the The Employer will have a right to
depute inspecting officers during the manufacture of the equipment. The Employer
reserves the right to carry out stage inspections at all stages, for which advance
intimation shall be given and all necessary cooperation shall be rendered by the
manufacturer.
17.4.
At the time of inspection, Bidder/manufacturer shall identify each and every
item/accessories of the particular Circuit Breaker under testing. Unless all the items
are identified, the manufacture will not be treated as complete. Various tests
stipulated in IS/IEC shall be performed in the presence of the Employer‘s engineers
or when the inspection waiver has been given, in such a case, testing shall be done
at the manufacturer's works as per IS/IEC stipulations and same should be confirmed
by documentary evidence by way of Test Certificate which shall be got approved by
the Employer.
17.5.
It is expected that before circuit breaker is finally offered for inspection, internal
testing of the same for various important parameters are already done. Routine test
report for such tests shall also accompany the letter of inspection call so that the
Inspecting Officer at the time of inspection may verify the parameters brought out in
the preliminary report. Details of all tests should be clearly brought out.
17.6.
In case for any reason, inspection is not completed or equipment is not found to
be complete with all accessories as per confirmation given with the letter of inspection
call, the Employer will reserve the right to recover complete cost of deputation of
inspecting team to the works of the manufacturer.
17.7.
Acceptance of any quantity of circuit breaker & its accessories shall in no way
relieve the successful bidder of his responsibility for meeting all the requirement of
this specification and shall not prevent subsequent rejection if such equipments are
later found to be defective.
18.0 RATING PLATES & SURFACE FINISH PAINTING & GALVANISING:18.1.
Each circuit breaker shall be provided with a detailed rating plate. Details on the
rating plate shall be as per ISS and shall also indicate manufacturer name, serial no.,
order no. and month & year of dispatch.
18.2.
All interiors and exteriors of tanks, mechanism, enclosures, cabinets and other
metal parts shall be thoroughly cleaned to remove all rust, scales, corrosion, greases
or other adhering foreign matter. All steel surfaces in contact with insulating oil, as far
as accessible, shall be painted with not less than two coats of heat resistant, oil
insoluble, insulating paint.
18.3.
All metal surfaces exposed to atmosphere shall be given two primer coats of zinc
chromate and two coats of epoxy paint with epoxy base thinner or hot dip galvanized
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or two packs of aliphatic polyurethane finished paint. All metal parts not accessible for
painting shall be made of corrosion resistant material. All machine finished or bright
surfaces shall be coated with a suitable preventive compound and suitably wrapped
or otherwise protected. Paints shall be carefully selected to withstand tropical heat
and extremes of weather within the limits specified.
18.4.
Paint shall not scale off or wrinkle or be removed by abrasion due to normal
handling. All external paintings shall be as per shade no. 697 or any other suitable
shade of IS:5 or polyurethane paint
18.5.
All ferrous parts & steel structure including all sizes of nuts, bolts, plain and
spring washers, support channels, structures, etc. shall be hot dip galvanized or
stainless steel or electro-galvanized.
19.0 DOCUMENTATION:
19.1.
List of Drawings and Documents: Bidders shall furnish four sets of relevant
descriptive and illustrative published literature, pamphlets and following drawings for
preliminary study;
(a) General outline drawings showing dimensions and shipping weights.
(b) Sectional views showing the general constructional features of the
circuit breaker
including operating mechanism, arcing chambers, contacts with lifting
dimensions for
maintenance.
(c) All drawings & data typical and recommended schematic diagram for
control
supervision & reclosing shall be annotated in English. .
(d) Schematic diagrams of breaker offered for control supervision and
reclosing.
(e) Structural drawing, design calculations and loading data for support
structures.
(f) Short circuit oscillogram & certificates for similar type tested breakers.
General
arrangement of foundation and structure mounting plan including weights of
varnish
components and impact loading data for foundation design.
(g) Type test reports.
19.2.
Successful bidders shall, within two weeks of placement of order, submit four
sets of final version of all the above drawings for the Employer's approval. The
Employer shall communicate his comments/approval on the drawings to the
Bidder/manufacturer within two weeks. Bidder/manufacturer shall, if necessary,
modify the drawings and resubmit four copies of the modified drawings for the
Employer's approval within two weeks from the date of comments. After receipt of the
Employer's approval, the Bidder/manufacturer shall, within three weeks, submit 4
prints per breaker and two set of good qualities reproducible of the approved
drawings for the Employer's use.
19.3.
Successful bidders shall also furnish two sets each of bound manuals covering
erection, commissioning, operation and maintenance instructions and all relevant
information and drawings pertaining to the main equipment as well as auxiliary
devices along with each breaker. Marked erection drawings shall identify the
component parts of the equipment as shipped to enable erection by the Employer‘s
own personnel. Each manual shall also contain one set of all the approved drawings,
type test reports as well as acceptance reports of the corresponding consignment
dispatched.
19.4.
Manufacturing of equipments shall be strictly in accordance with the approved
drawings and no deviation shall be permitted without the written approval of the
Employer.
19.5.
Approval of drawings/work by the Employer shall not relieve the bidders of any of
his responsibility and liability for ensuring correctness and correct interpretation of the
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drawings for meeting the requirements of the latest revision of the applicable
standards rules and codes of practices. Equipment shall conform in all respects to
high standards of engineering, design, workmanship and latest revisions of relevant
standards at the time of supply and the Employer reserves the right to reject any
equipment or material which, in his judgment, is not in full accordance therewith.
20.0 PACKING AND FORWARDING:
20.1.
Equipment shall be prepared for ocean shipment (foreign equipment) or rail road
transport (local equipment). Equipment shall be packed in suitable crates in such a
manner to protect it from damage and withstand handling during transit.
Bidder/manufacturer shall be responsible for and make good at his own expense any
or all damage to the equipment during transit, due to improper and inadequate
packing and handling. Easily damageable materials shall be carefully packed and
marked with the appropriate caution symbols. Wherever necessary, proper
arrangement for lifting such as lifting hooks etc. shall be provided. Any material found
short inside the packing cases shall be supplied by the Bidder/manufacturer without
any extra cost. Each consignment shall be accompanied by a detailed packing list
containing the following information:
(a) Name of the consignee.
(b) Details of consignment.
(c) Destination.
(d) Total weight of consignment.
(e) Sign showing upper/lower side of the crate.
(f) Handling and unpacking instructions.
(g) Bill of material indicating contents of
each package and spare material.
21.0 COMPLETENESS OF EQUIPMENT AND BOUGHT OUT ITEMS:
21.1.
Bidders must furnish following information along with technical bid. A list of all
the accessories which will be supplied with the breakers should be furnished. While
furnishing the list of accessories, items which will be manufactured by the Bidders
and balance items, which will be procured from sub-Bidder/manufacturers should be
clearly identified and stipulated in the bid.
22.0 GUARANTEED TECHNICAL PARTICULARS:
22.1.
It is obligatory on the part of bidders to furnish Guaranteed Technical Particulars
enclosed with the bid document duly filled in complete in all respects. In case
Guaranteed Technical Particulars duly filled in complete in all respects is not
furnished, the bid may be treated as non-responsive
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3.5
SPECIFICATION FOR INDOOR CONTROL PANELS for 11kV
OUTDOOR VCB
1.0 SCOPE
1.1. This section contains the technical specification for the multi circuit indoor control,
indication, relay and metering panels for control of associated line or transformer
through outdoor switchgear at various 33/11 KV sub-stations. The control and relay
panels and other requirements specified under this section shall be complete in
themselves with all main and auxiliary relays, annunciation relay, fuses, links, switches,
wiring, labels, terminal blocks, earthing terminals, base frame, foundation bolts,
illumination, cable glands etc.
2.0 PANEL FINISH AND COLOUR
2.1. The purchaser has standardized that the colour finish shall be opaline green as per
color no. 275 of BS:381C (1948). Equivalent colors as per relevant Indian Standards or
any other standard are also acceptable. This color finish shall be applied to all the
exterior steel work of the panels. The exterior finish shall be semi glossy only and shall
not be fully glossy. The interior of the panels shall be painted with egg shell white.
3.0 PROTECTIVE RELAYS AND INSTRUMENTS
3.1. The protective relays shall be manufactured, tested and supplied with the guaranteed
particulars, as per following Indian Standard Specifications with latest amendment
thereof :-
(i) IS-3842 (Part-I):1967 : Application guide for electric relays for A.C. Systems
over- current relays for Feeders and Transformers
(ii) IS-3842 (Part-IV):1967 : Application guide for electric relays for A.C.system
thermal protection relays
(iii) IS-3231 (1965) : Electric relay for power system protection
(iv) IS-1885 (Part-I&II) : Electro-technical vocabulary Electrical relays &
Electrical power
system protection
(v) IS-4483 : Preferred panel cut-out
(vi) IS-1248 : Indicating instruments
(vii) All indicating instruments shall conform to IS-722 or BS-89 or any
equivalent or better international standards...
The equipment meeting any other authoritative standards which ensures equal
or better quality than the standards mentioned above shall also be acceptable.
Equipment for which Indian Standards are not available the relevant British
Standards and IEC recommendations will be applicable. The bidder has to
submit copies of all applicable standards other than Indian along with the offer.
4.0 TYPE/ ACCEPTANCE TEST CERTIFICATES FOR RELAYS:4.1. Following type test certificates of relays as per IS: 3231 or any equivalent international
standard are required to be submitted by the bidder:-
(i) Performance test and operating characteristic tests
(ii) Thermal requirement test
(iii) Accuracy test
(iv) Re-set value test
(v) Re-set time test
(vi) Over shoot time test
(vii)Rated burden & impedance test
(viii)Insulation requirement test
(ix) Mechanical requirement test
(x) Contact performance test
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5.0 PANEL CUT OUT AND DIMENSIONS:5.1. The panels shall be fabricated from 2mm steel sheet free from all surface defects. The
panels shall have sufficient structural re-enforcement to ensure a plane surface to limit
vibration and to provide rigidity during dispatch and installation. All control panels and
switchgear cubicles shall be made absolutely vermin-proof. Pre-treatment & painting of
panels shall be done as per the procedure detailed in this schedule.
5.2. The panels shall have the following dimensions :-
Height 1475 mm
Depth 300 mm
Width 600 mm
No deviation in height and depth is permitted. However, to accommodate
instruments, relays, control and indication gadgets of different make, increase in
panel width alone is permitted, subject to specific approval of purchaser.
5.3. The preferred panel cut out dimensions for mounting of the relays shall be as per Indian
Standard Specification IS-4483 (Part - I & II).
5.4. Design, material selection and workman-ship shall be such as to present a neat
appearance, outside and inside with no works of welds, rivets, screw or bolts head
apparent from the exterior surface of the Control Panels.
6.0 PANEL LIGHTING:6.1. For interior illumination, 11/15 Watt CFL operating at 230V AC 50 Hz with On/Off switch
shall be provided in each panel. The lamp/tube shall be located at the ceiling and
guarded with protective cage. The On/Off switch shall be mounted on one of the
sidewalls and shall be easily accessible.
6.2. One 3 pin-5 Amp. receptacle socket with On/Off switch and fuse shall be provided in
each control panel.
7.0 INDICATING LAMPS:7.1. The indicating lamps should be supplied with low voltage protection circuit (LVGP) and
surge suppressor circuit having LED indication. Lamp assembly should be of fire
retardant glass epoxy PCB, industrial heat resistant, fire resistant, non- hygroscopic
DMC material, polycarbonate lens in desired color shades of Red, Green, Amber,
Yellow etc. the intensity of light should be minimum 100 mcd at 20 mA.
8.0 AUXILIARY SUPPLY:8.1. For each Control Panel, the purchaser will provide the following :-
i) 230V (+10% to -20%) single phase 2-wire, 50Hz neutral grounded
A.C.supply, frequency variation
±4%
ii) 110V (+ 10% to -15%) D.C. supply
9.0 CONTROL WIRING:9.1. The supplier shall provide complete wiring up to the terminal block for the equipment,
instrument devices mounted in the control panel strictly according to the wiring diagram
prepared by the supplier based on the purchaser‘s information and schematic diagram
and get approved from the purchaser.
9.2. The wiring shall be complete in all respects so as to ensure proper functioning of
control, protection and metering schemes. All unused potential free contacts of relays
and switches if any shall be wired up to the terminal block.
9.3. The Control Panels shall be supplied completely wired, ready for purchaser‘s external
connections at the terminal blocks.
9.4. For CT circuits, the wiring shall be carried out with 1100V grade PVC insulated
stranded copper conductor of size 2.5 sq.mm.
9.5. For PT and for control circuits the wiring shall be carried out with 1100 V Grade PVC
insulated stranded copper conductor of size 1.5 Sq.mm.
9.6. Color coded wires should be used to facilitate easy tracing, as under:-
i) Three Phase A.C. Circuit: - Red for R Phase, Yellow for Y Phase, Blue for B
Phase Black for Neutral,and Green for earthing.
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ii) Single Phase A.C. Circuit:-Red for Phase, Black for Neutral & Green for
Earthing.
iii) D.C. Circuit: - Red for Positive, Yellow for Negative.
iv) Control Wiring: - Gray for annunciation and other control circuits.
(f) Each wire shall be identified at both ends with wire designation number by
plastic ferrules, as per wiring diagram based on latest revision of IS-375 to
denote the different circuit functions.
(g) All wire termination shall be made with compression type connectors. Wires
shall not be tapped or spliced between terminal points. All wire shall have crimp
type termination and direct connection at any place is not at all required.
(h) All series connected devices and equipment shall be wired-up in sequence.
Loop-in/loop-out system of wiring shall be avoided, as far as possible and the
common buses shall normally be made through the terminal block for better
reliability of testing and maintenance.
(i) Fuses and links shall be provided for isolation of individual circuit from the
bus wires without disturbing the other circuits and equipments.
(j) The DC trip and DC voltage supplies and wiring to main protective gear shall
be segregated from these for back up protection and also for protective
apparatus for special purposes. Each such group shall be fed through separate
fuses, either direct from main supply fuses or the bus wires.
(k) Since, a number of wires will run from one point to another, it is desired that
the support arrangement should be adequate and neat. The conventional
method of bunching of wire should not be adopted, since the same may create
problems in case any wire is to be removed. The wires should be
accommodated in plastic channel with sliding plastic cover mounted inside the
panel, suitably. Inspection/removal of wires should be possible by sliding the
covers.
(l) Blank plastic channels should be provided by the sides of the panel to
accommodate the incoming cables from switchyard through the cable glands.
(m) The circuit diagram of control circuit along with operating instructions
(DO/DO‘NT) embossed on metallic plate duly laminated shall be provided on
rear side of the door.
10.0
TERMINAL BLOCKS:10.1.
Multi-way terminal blocks complete with necessary binding screws and washers
for wire connections and marking strips for circuit identification shall be provided for
terminating the panel wiring and outgoing cables. The terminal block shall be suitable
for receiving at least 2x2.5 sq.mm stranded copper conductor wire per terminal.
10.2.
Terminal blocks shall have shorting and disconnection facilities. The panel-side
and outgoing wires should be dis connectable just by opening the disconnecting links,
which slide up/down or left/right without dislodging the wires from their position.
However, disconnectable type terminal connectors with shorting facility may be limited
to CT & PT circuits only.
10.3.
Instrument transformer wires shall be terminated through suitably mounted test
terminal blocks for site testing facility.
10.4.
The terminal blocks shall be grouped according to circuit functions and each
terminal block group shall have at least 20% spare terminals. Adjacent rows of terminal
block shall be spaced not less than 100 mm apart. These shall be mounted vertically at
the sides of the cubicle and set obliquely towards rear doors to give easy access of
terminating end to enable ferrule number to be read without difficulty. The bottom of
terminal blocks shall be spaced at least 200 mm the cable gland of incoming multi-core
cables.
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11.0 CABLE ENTRY:11.1.
The control panel shall have provision of cable entry from the bottom. The box
base shall have 3 mm thick cover.
11.2.
The cover plate of base box for 11 KV and 33 KV MULTI CIRCUIT C&R panels,
shall be provided with 3 cable glands for 7 core, 5 cable glands for 4 core and 3 cable
glands for 2 core 2.5 sq.mm unarmored copper control cable.
11.3.
The gland plate shall be covered with dummy plate. The bidder has to provide all
required material to ensure IP55 protection. The purchaser will arrange for necessary
floor opening, below the panel and fixing of gland plate for control cable entry to suit the
supplier‘s requirement.
11.4.
The wiring through terminal blocks shall be such located so that it is convenient
for floor opening.
11.5.
For fixing cable glands on the box base cover, detachable gland plates of 4 mm
thick shall be mounted at least 100 mm above the floor level.
11.6.
The cable gland plate and rear door shall be properly rubber gasketted to ensure
IP-55 protection.
11.7.
Rigid supports shall be provided along the terminal block for holding plastic
channel. Suitable clamps shall also be provided in plastic channel for holding cables.
12.0 GROUNDING:12.1.
25mm x 6mm x 250mm copper ground bus shall be provided inside the panel for
effectively grounding all metal structures. Each continuous length of ground bus shall
have provision of two terminals at two separate points for connection to main ground
grid of the sub-station.
12.2.
Potential and current transformer neutrals shall be grounded only at the terminal
blocks where they enter the control panel from the instrument transformers.
12.3.
Wherever a circuit is shown grounded in the drawings, a single wire for the
circuit shall run independently to the ground bus and connected to it.
13.0 DOORS:13.1.
Each panel shall be complete with end enclosing sheets on both sides and door
in the rear. The rear door shall be fitted with handle and also turn twist locks at top and
bottom. Proper rubber sealing gasket shall be provided on the door. A type test report
from the recognized Government laboratory or NABL approved lab on degree of
protection test IP-55 shall be furnished by the supplier.
14.0 CONTROL AND RELAY PANELS:14.1.
The control panels required for installation at all the sub-stations shall be of
simplex type for multi circuit control. The control and indication apparatus, all meters
and relays shall be mounted in the front. The instruments and relays shall be flush
mounted pattern.
14.2.
The labeling for the circuits shall be provided at the front control panel, as well as
on the inside wall. All indicating instruments, meters and important components shall
have identification labels from inside also, in addition to outside. The terminal block
shall have identification labels attached to them, clearly indicating type of supply ‗AC &
DC identification circuits‘ control (metering/protection) and instruments identification.
For example, the terminal block shall have an identification indicating that is for CT
circuit, metering, protection etc.
14.3.
A mimic diagram showing single bus arrangement, with semaphore for breaker
position indicator etc. shall be provided for each circuit.
15.0 PROTECTION SCHEME:15.1.
The control panels are required for protection of 11 KV Overhead lines
The protection schemes are described in the following clause:15.2.
Feeder Protection :-
This will be in the form of a IDMT relay having 2 Nos. O/C and 1 No. E/F elements with
high set. The current settings of O/C relay element shall be from 2 % to 150% in equal
step of 1-2 % each and of E/F relay element from 2 % to 80%. They shall be suitable to
work on 110 Volt D.C. supply. The secondary rating of C.T. shall be 5 Amps. The
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numerical relays having programmable characteristics as per above requirements are
required. The relay shall be of draw out type with CT shorting facility. Further, the relay
shall have self re-set contacts and hand re-set flag arrangement. The tripping shall be
routed through a high speed master trip relay with hand reset facility and flag
relay.
16.0
CONTROL AND INDICATION CIRCUITS: -
11 KV feeders): 11 KV multi circuit control & relay panel for control of feeders shall
have
the following instruments, relays and accessories:1. Three pole 5 Amp Numeric IDMT relay 110 V DC with self-reset contacts and hand
reset flag (Flush pattern) shall be suitable for selecting following settings :a. O/C Element (2% to 200%) and E/F Element (2% to 80%) with high set
b. Operating Time plug setting With Multiple characteristics
2.Pistol grip Circuit Breaker Control switch T-N-C
3. Digital Ammeter of 96X96.mm size flush pattern CT operated sec 5 Amp with
Accuracy class 1.0.
4. Ammeter selector switch
5. Hand Reset Master trip Relay
6. Indicating Lamps as follows
a. CB-ON (RED)
b. CB-OFF (GREEN)
c. Trip ckt coil healthy (preclose and post close)- White
d. Auto trip (Amber)
e. Spring charged(Blue)
f. DC Fail relay
7.Push buttons for
a. Alarm accept
b. Alarm reset 2
c. Pre close Trip Circuit check coil-1
d. Pre close Trip Circuit check coil-2
8 Alarm Bell for DC fail
9 Alarm Buzzer AC fail
10. Cable glands with dummy cover suitable for 2.5 sq.mm Unarmored copper control
cable fitted on cover plate. For 2core, 4 core and 7 core.
11. Illumination CFL 11/15 Watt lamp with protective cage & On/Off Switch.
12 3 pin-5 A power socket with On/Off Switch. 1
13 MIMIC (10X3 mm) made of Aluminum strip painted black showing single bus and
breaker position semaphore indicator for isolator
14 Semaphore CB position indicator
3.15.4 The bidders are required to submit C&R panel general arrangement and
schematics indicating all relevant details of all relays and gadgets along with bill of
material.
.
NOTE: Any other indications or control equipments which are required for proper
protection/ operation of circuit breaker should be provided in control panel, without any
extra cost.
.
should organize services of their engineer at any site if any problem is reported either
by the purchaser
or field units.
13.18 TESTS:18.1 Each control panel shall be completely assembled, wired, adjusted and tested at
the factory, prior
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to dispatch.
18.2 The tests shall include wiring continuity tests, insulation tests and functional tests
to ensure
operation of the control scheme and individual equipment.
18.3 The test procedures shall have prior approval of the purchaser.
18.4 All instruments, meters and relays shall be tested and calibrated in accordance
with relevant
standards.
17.0
TEST CERTIFICATE:-
Each control & relay panel should be tested by the manufacturer at their works for all
routine and acceptance tests and copies of test certificate in duplicate giving results of
these tests shall be furnishedto the purchaser along with letter / offer for inspection.
18.0
WITNESSING OF TESTS
The routine/ acceptance tests results shall be witnessed by purchaser‘s representative,
if so desired by the purchaser, prior to dispatch of the equipment from the works. The
supplier shall give at least Fifteen (15) days advance notice of the date when the tests
are to be carried out.
19.0
TEST CERTIFICATE OF COMPONENTS:-
Test certificate for important components like Ammeter, Voltmeter, Relays and Control
Switch shall be produced at the time of inspection and shall be enclosed with the
inspection report.
20.0 PRE-TREATMENT AND PAINTING PROCESS:20.1.
The Control Panel sheet steel shall be subjected to pre-treatment process before
painting. The process shall be carried out as under. The procedure can broadly be
divided as ―Metal treatment‖ and ―painting‖.
(A) METAL TREATMENT:i) DEGREASING :This can be achieved either by immersing in hot alkaline degreasing bath or in
hot di-chloroethelene solution. In case degreasing is done by alkaline bath, rinse
with cold water thoroughly.
ii) PICKLING :This is to remove rust and metal scales by immersing in diluted sulphuric acid
(approximately 20%) at nearly 80 degree centigrade until scale and rust are
totally removed.
iii) Rinse in cold water in two tanks to remove traces of acids.
iv) Treat with phosphoric acid base neutralizer, for removal of chlorine from the
above acid pickling and again wash with running water.
v) PHOSPHATING :Immerse in grenadine Zinc phosphate solution for about 20 minutes at 80 to 90
degree centigrade. The uniform phosphate coating of 4 to 5 gms per sq. meter
shall be achieved.
vi) Swill in cold water.
vii) Rinse in deorylyte bath at 70 to 80˚C to neutralize any traces of salts.
viii) Seal the above phosphate coating with hot dilute chromate solution.
ix) Dry with compressed air.
(B) PAINTING:Sequence of process shall be as follows:
i) Spray one coat on wet surface by specially developed, ―High Luster‖ Zinc
chromate primer and stove at 150 to 160 degree centigrade for 25 to 30 minutes.
Alternatively, Red-Oxide primer with zinc chromate content may be used.
However, former process is preferred.
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ii) Rubbing and putting: - Apply putty to fill up scars, if any, to present smooth
surface and stove 15 to 20 minutes. Apply putty several times to get the perfectly
smooth finish.
iii) Surfacing:- Sand down with mechanical abrasive and stove for 20 minutes.
iv) Primer:- Spray second coat of primer as per (i) above or grey primer surface
on wet and stove for 30 to 40 minutes at 150 degree centigrade.
v) Finish Paint: - Rub down dry and spray first coat of synthetic enamel finish
paint on wet and stove for 30 minutes.
vi) Surfacing:- Sand down or rub dry to prepare for final finish. Spray 2 coats of
synthetic enamel finish paint on wet and stove it at 150 degree centigrade for 30
minutes.
NOTE:i) Necessary stiffeners may be welded between large cut outs to provide rigidity
before painting process.
ii) Painting process shall be done within 24 Hrs. of completion of metal
treatment.
iii) Small coating shall be supplied along with equipment for touching up at site.
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3.6
TECHNICAL SPECIFICATION FOR 11kV INDOOR VACUUM
SWITCHGEAR
1.0 SCOPE
1.1. This specification covers the manufacture, testing at manufactures works,
transport to site, insurance, storage, erection and commissioning of indoor 11
KV ,9 unit Panel switch boards which includes 11KV circuit breakers with
current transformers, voltage transformers, protective devices, protective
relays measuring instruments and meters etc. and wired complete with all
accessories as specified.
1.2. It may be noted that the 11 KV Indoor Vacuum Switchgear must meet the following
minimum criteria. Failure to comply with the requirements may results in rejection of
the BID as non-responsive:
1.2.1. The Manufacturer must have designed, manufactured, type tested and supplied
11 KV Indoor Vacuum Switchgear in at least two power utilities of similar rating
which are in successful operation for at least 5 (Five) years as on the date of bid
opening. Which should be substantiated by furnishing performance report by the
official of the rank of minimum DGM/SE
1.2.2. The manufacturer of the VCB must use their own make Vacuum Interrupter and
must have in-house manufacturing facility for Vacuum Interrupter & Breaker
(including mechanism)
1.2.3. Internal Arc Proof Panel – 25 kA for 0.1 sec with explosion vents on each HT
Compartment.
2.0 STANDARD
2.1.
Latest issues of the following standards shall be applicable.
I.S. 13118
I.S. 2705
I.S. 3156
I.S. 2099
I.S. 335
I.S. 1554
I.S. 3231
I.S. 1248
Circuit Breakers
Current transformers
Voltage transformers
Porcelain Bushing, High Voltage
Insulating oil
Cables
Electrical relays for power system protection
Electrical indicating instruments.
3.0 DRAWINGS, MANUALS, LITERATURES ETC.
3.1. The successful tenderer shall be required to submit to the purchaser for his
approval five copies of drawings and other details which include bue not
limited to the following:a) General out line drawings with full dimensions.
b) Detailed drawings showing the mounting arrangement of the switchboards,
provisions for cable entries etc.
c) Detailed drawings showing the provisions kept for extension of the
switchboards.
d) List of all component parts, fittings and accessories of the switchboards with
maker‘s name, type, ratings etc.
e) A.C. and D.C. schematic and wiring diagrams.
3.2. After approval of drawings the tender shall submit to the purchaser for the
reference and record five copies of the above drawings including the following
leaflets / manuals (in sic copies):
a) Instruction books / operation and maintenance manuals for circuit breaker
and other
component parts.
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Technical Specification
b) Descriptive literature/leaflets on construction and other details of circuit
breakers and other
component parts.
3.3. In addition to the above successful tenderer shall supply three sets of all the
above final drawings, literatures, manuals etc under a common cover with
each and every sets of switchboard. All the above drawings, literatures,
manuals etc. shall from a part of the contract.
4.0 TECHNICAL SPECIFICATION:
4.1. The switchboard shall be metal enclosed, floor mounting, single front self
supporting cubical type suitable for indoor. The switchgear shall be easily
extendable in future.
4.2. The switchgear assembly shall be designed for the power system having the
following parameters.
a). Nominal system voltage: 11KV
b). Highest system voltage: 12KV
c). Frequency: 50 Hz.
d). System earthing: Solidly earthed neutral
e). System fault level: 250 MVA
f). Degree of protection of switchgear assembly: 1PH3 as per IS: 3427
5.0 CONSTRUCTIONAL FEATURES:
5.1. The 11 KV switchgear panels shall be made of stretched leveled steel plates
of thickness not less than 3 mm and structural steel having light sections.
5.2. The steel panel and frame work shall have rigorous surface treatment before
application of suitable primer and two coats of paints, painting shall be a anticorrosive and anti-condensive type.
5.3. Each panel shall be divided into independent compartment completely
isolated from one another to house the circuit breaker, instruments, relay, bus
bar, cable boxes etc. The front compartment housing the breaker shall be
such that the breaker can be taken out only when it is in open condition.
5.4. The switchgear boards shall have a single front, single tier, fully
compartmentalized, metal enclosed construction, comprising of row of
freestanding floor mounted panels. Each circuit shall have a separate vertical
panel with distinct compartments for circuit breaker ,cable termination, main
busbar and auxiliary control devices. The adjacent panels shall be completely
separated by steel sheets except in busbar compartments where insulated
barriers shall be provided to segregate adjacent panels. However,
manufacturer‘s standard switchgear design without internal barriers in busbar
compartment may also be considered.
5.5. The circuit breakers and bus PTs shall be mounted on withdrawable trucks,
which shall roll out horizontally from service position to isolated position. The
breaker truck shall be floor mounted so that it can easily be pulled out on the
control room floor and the help of trolly etc. are not to be utilized.
5.6. The switchgear assembly shall be dust, moisture, rodent and vermin proof,
with the truck in any position SERVICE, ISOLATED, TEST or removed, and
all doors and covers closed. All doors, removable covers and glass windows
shall be gasketted all round with synthetic rubber or neoprene gaskets.
5.7. The bus VT/relay compartments shall have degree of protection not less than
IP : 52 in accordance with IS:2147. However, remaining compartments can
have a degree of protection of IP:42. All louvers if provided shall have very
fine brass or GI mesh screen, IPH-2 degree of protection as per IS: 3427 to
all live parts shall (whether isolated or removed from panel) even when the
breaker compartment door is open. Tight fitting garments / gaskets are to be
provided at all openings in rely compartment.
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5.8. Circuit breaker shall be vacuum; draw out type housed in a separate
cubicle of the switchboard and shall be enclosed from all sides. A sheet steel
hinged lockable door shall be at the front. It shall be possible to withdraw the
circuit breaker to ‗Test‘ and ―Isolated‘ position with the door closed. Door
interlock shall be provided such that the door can only be opened after
withdrawing the breaker to ‗Isolated‘ position and the breaker cannot be
racked into the ‗Service‘ position unless the door is closed. A visual
indication as to show when the breaker is in „Service‟, „Test‟ of „Isolated‟
position shall be provided in front of the door.
5.9. The switchgear shall be cooled by natural airflow and cooling by any other
method shall not be accepted.
5.10.
Total height of the switchgear panels shall not exceed 2600 mm. The
height of switches, pushbuttons and other hand-operated devices shall not
exceed 1800 mm and shall not be less than 700mm.
5.11.
Switchgear construction shall have a bushing or other sealing
arrangement between the circuit breaker compartment and the busbar / cable
compartments, so that there is no air communication around the isolating
contacts in the shutter area with the truck in service position.
5.12.
The breaker and the auxiliary compartments provided on the front side
shall have strong hinged doors, busbar and cabling compartments provided
on the rear side have bolted compartment covers with self retaining bolts.
Breaker compartment doors shall have locking facility.
5.13.
In the service position, the truck shall be so secured that it is not
displaced by short circuit. Busbars, jumpers and other components of the
switchgear shall also be properly supported to withstand all possible short
circuit forces corresponding to the short circuit rating specified.
5.14.
Suitable base frames made out of steel channels shall be supplied along
with necessary anchor bolts and other hardware, for mounting of the
switchgear panels. These shall be dispatched in advance so that they may be
installed and leveled when the flooring is being done, welding of base frame
to the insert plates as per approval installation drawings.
5.15.
The switchboard shall have the facility of extension on the both sides
Adopter panels and dummy panels required to meet the various busbar
6.0 CIRCUIT BREAKER RATING
6.1. FOR INCOMER(2 Nos.)
6.2. FOR BUS COUPLER(1 No.)
6.3. FOR OUTGOING FEEDER (6 Nos.)
7.0
CURRENT TRANSFORMER RATING
7.1. FOR TRANSFORMER INCOMING
(i) Accuracy class : a) Core -I
: 0.5 with ISF less than 5
b) Core –II
: 5 P with ALF 10
c) Core –III
: PS (for 3 core CT only)
(ii) Rated Burden
a) Core –I
: 30 VA
b) Core –II
: 15 VA
(iii) Knee point voltage :
100 volts (for core –III )
(v) Ratio:
: 600-300-150/5-5-2.89
7.2.
Current Transformers for outgoing (feeders)
(i) Ratio
: 400-200/5-5
(ii) Accuracy class : a) Core -I
: 0.5 with ISF less than 5
b) Core –II
: 5 P with ALF 10
(iii) Rated Burden : a) Core –I
:30 VA
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Technical Specification
7.3.
b) Core –I
: 15 VA
Current Transformers for Bus Section
(i) Ratio
: a) 600-300/5-5
(ii) Accuracy class
: a) Core -I
: 0.5 with ISF less than 5
b) Core –II
: 5 P with ALF 10
(iii) Rated Burden
: a) Core –I
: 15 VA
b) Core –I
: 15 VA
8.0 POTENTIAL TRANSFORMERS
8.1. . The tenderer shall quote for oil immersed or cast-resin type having the
following particulars for the purpose of metering:
1. Rated voltage ratio
: 11000/110
2. No. of phases
: 3 Phases / star - star connected
3. Rated Burden
: 100 VA per phase
4. Class of accuracy
: 0.5
5 Primary wiring of the PTs shall be protected by suitable H.R.C. fuse.
8.2.
Two sets of 11 KV/110 V PTs shall be provided
9.0 PROTECTIVE RELAYS:
9.1. All the incoming and outgoing switchgear units shall be provided protective
relays to disconnect the faulty circuits with speed and certainty without
interfering with healthy circuits.
9.2. The protective relays mounted on the panels shall be of the draw out type.
The relavs must be capable of resetting without necessity of opening the
case. The relays shall be provided with flag indicates to enable the type of
fault conditions to be identified.
9.3. Incoming and outing feeders units and the bus coupler panel shall be
provided with combined over current and earth fault relay with current range
of 50-200% for O/C with inverse characteristics and 20-80% for E/F relay of
time range 0.3 secs at 10 times current.
10.0
MEASURING INSTRUMENTS
10.1.
All instruments shall be switchboard type, back connected, suitable for
flush mounting and shall comply with the requirements of latent issues of
relevant Indian Standards. The instrument cases shall be dust proof, water
tight, vermin proof and specially constructed to adequately protect the
instruments against damage or deterioration due to high ambient temperature
and humidity.
10.2.
All instruments shall be access adjustable and calibrated before dispatch
and shall have means for calibration check and adjustment at site.
10.3.
All ammeters shall be digital type with direct reading scales. The scale
value of ammeters shall be as per the primary current ratings of the
associated current transformers. The rated current of ammeter elements shall
be 5 ampere and accuracy class 1.0 as per IS: 1248.
10.4.
All voltmeters shall be of digital type with direct reading scales. The
maximum scale value of voltmeters shall be 50% in access of the primary
voltage of associated PT. The rated voltage of the voltmeters shall be 110
volts A.C. and accuracy class shall be 1.0 as per IS: 1248.
10.5.
Indicating wattmeters shall be of digital type of accuracy class 1.
10.6.
Energy meters shall be digital type of accuracy class 0.5.and of
Secure make or L&T make preferably as per APDCL Spec
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11.0 SMALL WIRING AND TERMINAL BLOCKS
11.1.
All panels shall be furnished completely factory wired up to terminal
blocks ready for external connections. All wiring shall be switchboards type,
with annealed copper wires with PVC insulation for 1100 volts complying with
requirements of latest issue of IS: 1554 (Part-I). The sizes of the wiring for
different circuits shall be go chosen as to provide ample margin for the
purposes intended and shall be subjected to approval of the purchaser.
However minimum cross section of wires t be used shall not be less than 1.5.
sq.m. All the operating coils and small wires shall withstand a power
frequency ten voltage of 2 KV for one minute.
12.0
SAFETY EARTHING
12.1.
Earthing of current free metallic parts of metallic bodies of the equipment
on the panel and the switchboards shall be done with soft drawn single
conductor bare cooper. A copper ground bus extending the entire length of
the panels shall be provided. Suitable clamp type terminals shall be provided
for connecting both ends of the bus to the station earth system. The earth
connection of instrument transformers wherever necessary shall be
connected with the main earth wire of the panel earthing system. Multilpe
earthing of any instrument transformer circuit shall be avoided.
13.0
CABLE BOXES AND CABLE GLANDS:
13.1.
Cable boxes with cable glands shall be supplied with each of the panel. It
should be of adequate dimension for terminals of 11 KV cables of sizes 300
and 185 sqmm and 180 sq.mm.
13.2.
The 11 KV cable boxes shall preferably be located at the back of the
switchboards and shall be suitably mounted for cables rising from cable
trenches running at floor of the control room. The cable glands provided at the
entrance shall facility for earthing of amounting.
13.3.
All control/Wire entries should be by means of suitable cable glands such
glands should be of brass and tinned.
14.0
DETAILS OF FITTING AND ACCESSORIES
14.1.
The 11 KV switchboards shall consist of the following equipments for
each incoming outgoing and bus-coupler panels as per single line diagram
enclosed.
14.2.
Incoming panel (Transformer panel)
I. Circuit Breaker:
1 No.
: - Triple pole circuit breaker. With continuous current
rating of 800A. :Manually, charged independent spring
closing, mechanism fitted with mechanical ―ON‖ and ―OFF‖
indications.
1 No. : Hand trip device.
1 No. : Shunt trip coil suitable for 110 D.C.
II. Meters and Instrument:
1 No.
: Ammeter with selector switch.
1 No.
: Voltmeter with selector switch.
1 No.
: Electronic Tri-vector Meter
1 No.
: Test terminal block for meters.
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III. Relays:
1 Set
1 Set
Indication
: Over current and earth fault relay.
: Testing links and terminals for relays.
2 No.
: Indicating lamps for indication of „ON‟ and „OFF‟ position of breaker.
1 No.
: Indicating lamp labeled “trip Circuit healthy” with push button.
IV.
Annunciation:
Annunciation: No annunciation facia shall be provided for Outgoing panel
V. Other Equipments and fitting:
Same as for incoming panel but cable box shall be suitable for following size of cable:
1 No. : 3 core 11 KV cable of size up to 630 sq.mm.
14.3.
BUS SECTION PANEL:
Same as detailed for incoming panel in clause 7.16.1 but with following
modifications/additions/deletions:
I. Circuit Breaker: 800 A
II. Current and potential transformer
NO Potential transformer required, CT ratio as specified for bus section panel.
III.
Meters and Instruments:
All meters except the ammeter with selection switch shall be deleted.
IV.
Relays:
Only 1set O/C & E/F relay shall be provided.
V.
Indication:
Indicating lamp labeled “Auto trip” with accept push button associated with Auto trip alarm
shall be added.
VI.
Annunciation:
No annunciation facia shall be provided for bus section panel.
VII.
Other Equipments and Fittings:
Cable box shall be deleted.
14.4.
I.
COMMON ALARM AND ANNUNCIATION:
Each switchboard shall be provided with a suitable common alam system for:
a). D.C. Power supply failure.
b). A.C. Power supply failure.
c). Auto trip alarm.
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II.
III.
IV.
An AC operated relay with AC buzzer and AC indicating lamp shall be provided for
annunciation of DC failure.
A DC operated relay with DC buzzer and DC lamp shall be provided for AC failure.
Alarm and annunciation scheme shall be provided completed with horns, buzzers,
relays, alarm connection push buttons, alarm test push buttons etc.
15.0
CIRCUIT LABELING:
15.1.
Each switchgear shall be appropriately such as ‗INCOMING
TRANSFORMER‘, OUTGOING – FEEDER and BUS – SECTION‘,
Associated Circuit breaker ratings, CT & PT ratio and any other information,
manufacturer feels necessary shall also be included in the label.
16.0
PERFORMANCE GUARANTEE
16.1.
The bidder shall offer equipment performance guarantee for a
minimum period of 1 year from the date of commissioning.
17.0
.
SPECIAL TECHNICAL SPECIFICATIONS OF SWITCHGEAR:
17.1.
Switchgear shall be installed on finished surfaces, concrete or steel sills.
Contractor shall be required to install and align any channels sills, which form
part of foundations. Circuit breaker trolley wheels shall move on channels,
which shall form part of floor. The channel length shall be minimum of 1-meter
form the door of switchgear panel. Power bus enclosure, ground and control
splices of conventional nature shall be cleaned and bolted together with
torque wrench of proper size or by other approved means. Tape or compound
shall be spilled where called for in drawing Contractor shall take utmost care
in handling instruments, relays and other delicate mechanism. Wherever the
instruments and relays are supplied loose along with switchgear, they shall be
mounted only after the associated switchgear panels have been erected and
aligned. The blocking materials, employed for safe transit of instrument and
relays shall be removed after ensuring that panels have been completely
installed and no further movement of the same would be necessary. Any
damage shall be immediately reported to Engineer.
17.2.
Foundation work for all switchgear panels will be carried out by
contractor. For R&M of existing substation foundation work shall be done
wherever required as per site condition.
17.3.
Circuit breaker may be provided with inter pole barriers of insulting
materials, if the same is standard design of the manufacture. But use of
inflammable materials like Hylam shall not be acceptable.
17.4.
The control switch located on the switchgear would normally be used for
operation of circuit breaker in service/isolated position, and for tripping it in an
emergency.
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17.5.
Facilities shall be provided for mechanical tripping of the breaker.
17.6.
Auxiliary contacts of breaker may be mounted in the fixed portion or in
withdraw able truck as per the standard practice of the manufacture, and shall
be directly operated by the breaker operating mechanism.
17.7.
Auxiliary contacts mounted in the portion shall not be operable by
the operating mechanism, once the truck is withdrawn from the service
position, but remain in the position corresponding to breaker open position.
Auxiliary contacts mounted on the truck portion and dedicated for use shall be
wired out in series with a contact denoting breakers service position. With
truck withdrawn, the auxiliary contacts shall be operable by hand for testing.
17.8.
For Employer‘s use six (6) normally opened (NO) and six (6)
normally closed (NC) auxiliary contacts shall be wired out to the terminal
blocks. Contact multiplication, if necessary to meet the above contact
requirement, shall be done through suitable latch relay of English Electric type
VAJC-11 or equivalent.
17.9.
It shall be possible to easily insert breaker contractor of one feeder into
any one of the panel meant for same rating but at the same time shall be
prevented from inserting it into panels meant for a different type of rating.
17.10. All bus bar and jumper corrections shall be of high conductivity copper or
aluminium alloy. They shall be adequately supported on insulators to
withstand electrical and mechanical stresses due to specified short circuit
currents.
17.11. Busbar joints shall be bolted type.
17.12.
Busbar cross-section shall be uniform throughout the length of
switchgear. Busbar and other high voltage connection shall be sufficiently
corona free at maximum working voltage.
17.13.
Contact surfaces at all joints shall be silver plated or properly
cleaned and no oxide grease applied to ensure an efficient and trouble free
connection. All bolted joints shall have necessary plain and spring washers.
All connection hardware shall have high corrosion resistance. Suitable
bimetallic connectors shall be used for aluminium to copper connections.
17.14.
Busbar insulators shall be of arc and track resistant high strength,
non-hygroscopic, non-combustible type and shall be suitable to withstand
stresses due to over-voltages, and short circuit current. Busbar shall be
supported on the insulators such that the conductor expansion and
contraction are allowed without straining the insulators. In case of organic
insulator partial discharge shall be limited to 100 pico coulomb at rated
voltage x1.1/ 3. Use of insulators and barriers of inflammable material such as
Hylem shall not be accepted.
17.15.
All busbur shall be colour coded.
17.16.
The temperature of the busbars and all other equipment, when
carrying the rated current continuously shall be limited as per the stipulations
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of relevant India Standards, duly considering the specified ambient
temperature (50 deg. C). The temperature rise of the horizontal and vertical
busbars when carrying the rated current shall be in no case exceed 55 deg.C
for silver plated joints and 35 deg.C for all other type of joints. The
temperature rise at the switchgear terminals intended for external cable
termination shall not exceed 35 deg.C. Further the switchgear parts handled
by the operator shall not exceed a rise of 5deg.C.
18.0
PAINTING:
18.1.
Al sheet steel work shall be pretreated in tanks in accordance with
IS: 6005. Degreasing shall be done by alkaline cleaning. Rust and scale shall
be removed by pickling with acid. After pickling, the parts shall be washed in
running water. Then these shall be rinsed in slightly alkaline hot water and
dried. The phosphated coating shall be Class ‗C‘ as specified in IS: 6008. The
phosphated surface shall the rinsed and passivated prior to application of
stoved lead oxide primer coating. After primer application, two coats of
finishing synthetic enamel paint on panels shall be applied. Finishing paint on
panels shall be shade 692 (smoke grey) of IS: 5 unless specified otherwise by
the Owner. The inside of the panels shall preferably be glossily white. Each
coat finishing shall be properly stoved. The paint thickness shall not be less
than 50 microns. Finished surfaces from scratches, grease dirt‘s and oily
spots during testing, transporation, handling and erection.
19.0
SWITCHGEAR WIRING
19.1.
All switchgear panels shall be supplied completely wired internally upto
the terminal block ready to receive external cabing. All inter cubicle wiring and
connections between panels of same switchboard including all bus wiring for
AC and DC supplies shall be provided by the Contractor.
All internal wiring shall be carried out 650 grade, single core, 1.5 sq.mm, stranded copper wires
having minimum of seven strands per conductor and colour coded, PVC insulation. CT circuits
shall be wired with 2.5 sq.mm. wires which otherwise are similar to the above. Extra flexible
wires shall be used for wiring between fixed and moving parts such as hinged doors.
All wiring shall be properly supported neatly, readily accessible and securely connected to
equipment, terminals and termenal blocks. Wiring troughs or gutters be used for this purpose.
19.2.
Internal wire terminals shall be made with solder less crimping type
tinned copper lugs, which shall firmly grip the conductor. Insulation sleeves
shall be provided over the exposed parts of lugs. The lugs related to CT
secondary circuit wiring shall be hole type.
19.3.
Engraved core identification plastic ferrules marked to correspond with
panel wiring diagrams be fitted at both ends of each wire number 6 and 9
shall not be used for wire identification. Ferrules shall fit tightly on wires and
shall not fall off when wire is, disconnected from terminal. All wires directly
connected to trip the circuit breaker shall be distinguished by the addition of a
red coloured unlettered ferrule.
19.4.
Inter connection to adjacent panels shall be brought out to a separate set
of terminal blocks located near the slots or holes, meant for the
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interconnecting wires. Arrangement shall permit neat layout and easy inter
connections to adjacent panels at site and wires for this purpose shall be
provided by Contractor looped and bunched properly inside the panels. The
inter panel wires shall be cross ferruled i.e. it shall have details of emanating
terminal and also where it is terminated.
19.5.
Manufacturer shall be fully responsible for the completeness and
correctness of the internal wiring and for the proper functioning of the
connected equipment.
19.6.
The Manufacturer shall provided the necessary clamps wiring
troughs etc. for all wiring in side the switchgear enclosed including the power
and control cables.
20.0
POWER CABLE TERMINATION:
20.1.
The cable termination compartment shall received the stranded
aluminium conductor, XLPE insulated, shielded, armoured / unarmoured,
PVC jacketed, single core / three core unearthed / earthed grade power cable
(s).
20.2.
A minimum clearance of about 600 mm shall be kept between the cable
lug bottom ends and gland plates for stress cone formation for XLPE Cable.
Interphase clearance in the cable termination compartment shall be adequate
to meet electrical and mechanical requirement besides facilitating easy
connections and disconnections of cables. Dimensional drawing of cable
connected compartment showing the location of lug, glands, CTS, gland
plates etc. and the electrical clearances available shall be submitted
Employer approval during detailed engineering.
20.3.
Cable termination compartment shall be complete with power terminals,
power lugs and associated hardware and removable undrilled gland plates.
Fopr all single core cables grand plates shall be of nonmagnetic material.
20.4.
Supply of the cable termination kit and cable termination shall be in scope
of contractor.
21.0
TESTS:
21.1.
The Contractor shall submit the type test reports of following type tests
for approval of the Employer for circuit breaker, circuit breaker panels, of each
voltage class and current rating:
i). Short circuit duty test on circuit breaker, mounted inside the panel offered along with CTs,
bushing and separator.
ii). Short time withstand test – on circuit breaker, mount inside panel offered together with CTs,
bushing and separator.
iii). Power frequency withstand test on breaker and panel.
iv). Lighting impulse withstand test on breaker and panel.
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v)The indoor VCB switchgear should have internal arc test
conducted at CPRI
21.2.
Temperature rise test on breaker and panel together. For this test, the
test set up shall include three panels with breakers, the test breaker and
panel being placed in the center. The adjacent panels shall also be loaded to
their current capacity. Alternatively the test panel may be suitably insulated at
the sides, which will be adjoining to other panels in actual site configuration.
..
21.3.
. Switching over-voltage test as per clause 3.2(b) on each rating of
breaker.
a. Measurement of resistance of main circuit.
b. Mechanical eduranc4e test on breaker.
c. Mechanical operation test.
Viii). Short circuit withstand test of earthing device (Truck / Switch).
21.4.
For all the important components like instrument transformers, relays,
instruments, switches, bushing, wires, insulators, timers, annunciation,
terminal blocks and fuses etc. the contractor shall furnish satisfactory type
test reports for Employer‘s approval. Such reports cover all applicable type
test listed in relevant Indian Standards, for all components of type and rating
being supplied.
22.0
COMMISSIONING CHECKS / TESTS
22.1.
After installation of panels, power and control wiring and connect
contractor shall perform commissioning checks as listed below to proper
operation of switchgear / panels and correctness of all respects.
22.2.
GENERAL
a). Check name plate details according to specification.
b). Check for physical damage.
c). Check tightens of all bolts, clamps and connecting terminal.
d). Check earth connections.
e). Check cleanliness of insulators and bushings.
f). Check heaters are provided.
g). H.V. test on complete switchboard with CT & breaker / contractor lubricated in position.
h). Check all moving parts are properly lubricated.
i). Check all alignment of bus bars with the insulators to ensure alignment and fitness of
insulators.
j). Check for inter changeability of breakers.
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k). Check continuity and IR value of space heater.
l). Check earth continuity of the complete switchgear board.
22.3.
CIRCUIT BREAKER
a). Check alignment of trucks for free movement .
b). Check correct operation of shutters.
c). Check show closing operation (if provided).
d). Check control wiring for correctness of corrections, continuity and IR values.
e). Manual operation of breakers completely assembled.
f). Power closing / opening operation manually and electrically at extreme condition of control
supply voltage.
g). Closing and tripping time.
h). Trip free and anti-pumping operation.
i). IR values, resistance and minimum pick up voltage of coils.
j). Simultaneous closing of all the three phases.
k). Check electrical and mechanical inter locks provided.
l). Checks on spring charging motor, correct operation of limit switches and time of charging.
m). Check vacuum (as applicable).
n). All functional checks
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3.7
1.0
1.1.
1.2.
1.3.
2.0
2.1.
2.2.
2.3.
3.0
3.1.
3.2.
3.3.
3.4.
3.5.
3.6.
TECHNICAL SPECIFICATION FOR 33KV & 11 KV ISOLATORS
SCOPE
This section of the specification is intended to cover design specifications for
manufacture and testing of 33 KV and 11 KV gang operated switch (Isolators)
with all fittings and accessories.
The Isolators are for outdoor installation suitable for horizontal/vertical mounting
on mounting structures and for use at sub-stations.
Isolators shall be supplied with Earth Switch as and where specified.
GENERAL
The Isolators and accessories shall conform in general to IS 9921 (or IEC:
62271-102) except to the extent explicitly modified in specification.
All isolating switches and earthing switches shall have rotating blades and
pressure releasing contacts. All isolating and earth switches shall operate
through 90 angle from closed position to fully open position.
Complete isolator with all the necessary items for successful operation shall be
supplied including but not limited to the following:
(i). Isolator assembled with complete base frame, linkages, operating
mechanism, control cabinet, interlocks etc.
(ii). All necessary parts to provide a complete and operable isolator installation,
control parts and other devices whether specifically called for herein or not.
(iii). The isolator shall be designed for use in the geographic and meteorological
conditions as given in Section 1.
DUTY REQUIREMENTS
Isolators and earth switches shall be capable of withstanding the dynamic and
thermal effects of the maximum possible short circuit current of the systems in
their closed position. They shall be constructed such that they do not open under
influence of short circuit current.
The earth switches, wherever provided, shall be constructionally interlocked so
that the earth switches can be operated only when the isolator is open and vice
versa. The constructional interlocks shall be built in construction of isolator and
shall be in addition to the electrical and mechanical interlocks provided in the
operating mechanism.
In addition to the constructional interlock, isolator and earth switches shall have
provision to prevent their electrical and manual operation unless the associated
and other interlocking conditions are met. All these interlocks shall be of failsafe
type. Suitable individual interlocking coil arrangements shall be provided. The
interlocking coil shall be suitable for continuous operation from DC supply and
within a variation range as stipulated elsewhere in this specification.
The earthing switches shall be capable of discharging trapped charges of the
associated lines.
The isolator shall be capable of making/breaking normal currents when no
significant change in voltage occurs across the terminals of each pole of isolator
on account of make/break operation.
The isolator shall be capable of making/breaking magnetising current of 0.7A at
0.15 power factor and capacitive current of 0.7A at 0.15 power factor at rated
voltage.
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Technical Specification
4.0
CONSTRUCTIONAL DETAILS
4.1.
All isolating switches and earthing switches shall have rotating blades and
pressure releasing contacts. All isolating and earth switches shall operate
through 90 angle from closed position to fully open position.
4.2.
Contacts:
a) The contacts shall be self-aligning and self-cleaning and so designed that
binding cannot occur after remaining closed for prolonged periods of time in
a heavily polluted atmosphere.
b) No undue wear or scuffing shall be evident during the mechanical endurance
tests. Contacts and spring shall be designed so that readjustments in contact
pressure shall not be necessary throughout the life of the isolator or earthing
switch. Each contact or pair of contacts shall be independently sprung so
that full pressure is maintained on all contacts at all time.
c) Contact springs shall not carry any current and shall not lose their
characteristics due to heating effects.
d) The moving contact of double break isolator shall have turn-and -twist type
or other suitable type of locking arrangement to ensure adequate contact
pressure.
4.3.
Blades:
a) All metal parts shall be of non-rusting and non-corroding material. All current
carrying parts shall be made from high conductivity electrolytic
copper/aluminium. Bolts, screws and pins shall be provided with lock
washers. Keys or equivalent locking facilities if provided on current carrying
parts, shall be made of copper silicon alloy or stainless steel or equivalent.
The bolts or pins used in current carrying parts shall be made of noncorroding material. All ferrous castings except current carrying parts shall be
made of malleable cast iron or cast-steel. No grey iron shall be used in the
manufacture of any part of the isolator.
b) The live parts shall be designed to eliminate sharp joints, edges and other
corona producing surfaces, where this is impracticable adequate corona
shield shall be provided..
c) Isolators and earthing switches including their operating parts shall be such
that they cannot be dislodged from their open or closed positions by short
circuit forces, gravity, wind pressure, vibrations, shocks, or accidental
touching of the connecting rods of the operating mechanism.
d) The switch shall be designed such that no lubrication of any part is required
except at very infrequent intervals i.e. after every 1000 operations or after 5
years whichever is earlier.
4.4.
Insulators:
a) The insulator shall conform to IS: 2544 and/or IEC-60168. The insulators
shall have a minimum cantilever strength of 400 Kgs. for 33/11 kV insulators
respectively.
b) Pressure due to the contact shall not be transferred to the insulators after the
main blades are fully closed.
4.5.
Base:
Each isolator shall be provided with a complete galvanised steel base provided
with holes and designed for mounting on a supporting structure.
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Technical Specification
5.0
EARTHING SWITCHES
5.1.
Where earthing switches are specified these shall include the complete operating
mechanism and auxiliary contacts.
5.2.
The earthing switches shall form an integral part of the isolator and shall be
mounted on the base frame of the isolator.
5.3.
The earthing switches shall be constructionally interlocked with the isolator so
that the earthing switches can be operated only when the isolator is open and
vice versa. The constructional interlocks shall be built in construction of isolator
and shall be in addition to the electrical interlocks.
Suitable mechanical arrangement shall be provided for de-linking electrical drive
for mechanical operation.
5.4.
Each earth switch shall be provided with flexible copper/aluminum braids for
connection to earth terminal. These braids shall have the same short time
current carrying capacity as the earth blade. The transfer of fault current through
swivel connection will not be accepted.
5.5.
The frame of each isolator and earthing switches shall be provided with two
reliable earth terminals for connection to the earth mat.
5.6.
Isolator design shall be such as to permit addition of earth switches at a future
date. It should be possible to interchange position of earth switch to either side.
5.7.
The earth switch should be able to carry the same fault current as the main
blades of the Isolators and shall withstand dynamic stresses.
6.0
6.1.
6.2.
6.3.
7.0
7.1.
7.2.
7.3.
7.4.
OPERATING MECHANISM
The bidder shall offer manual operated Isolators and earth switches..
Control cabinet/operating mechanism box shall be made of aluminum sheet of
adequate thickness (minimum 3 mm).
Gear should be of forged material suitably chosen to avoid bending/jamming on
operation after a prolonged period of non-operation. Also all gear and connected
material should be so chosen/surface treated to avoid rusting.
OPERATION
The main Isolator and earth switches shall be gang operated.
The design shall be such as to provide maximum reliability under all service
conditions. All operating linkages carrying mechanical loads shall be designed
for negligible deflection. The length of inter insulator and interpole operating rods
shall be capable of adjustments, by means of screw thread which can be locked
with a lock nut after an adjustment has been made. The isolator and earth
switches shall be provided with ―over center‖ device in the operating mechanism
to prevent accidental opening by wind, vibration, short circuit forces or movement
of the support structures.
Each isolator and earth switch shall be provided with a manual operating handle
enabling one man to open or close the isolator with ease in one movement while
standing at ground level. Detachable type manual operating handle shall be
provided. Suitable provision shall be made inside the operating mechanism box
for parking the detached handles. The provision of manual operation shall be
located at a height of 1000 mm from the base of isolator support structure.
The isolator shall be provided with positive continuous control throughout the
entire cycle of operation. The operating pipes and rods shall be sufficiently rigid
to maintain positive control under the most adverse conditions and when
operated in tension or compression for isolator closing. They shall also be
capable of withstanding all torsional and bending stresses due to operation of the
isolator. Wherever supported the operating rods shall be provided with bearings
on either ends. The operating rods/ pipes shall be provided with suitable
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Technical Specification
universal couplings to account for any angular misalignment.
7.5.
All rotating parts shall be provided with grease packed roller or ball bearings in
sealed housings designed to prevent the ingress of moisture, dirt or other foreign
matter. Bearings pressure shall be kept low to ensure long life and ease of
operation. Locking pins wherever used shall be rustproof.
7.6.
Signaling of closed position shall not take place unless it is certain that the
movable contacts, have reached a position in which rated normal current, peak
withstand current and short time withstand current can be carried safely.
Signaling of open position shall not take place unless movable contacts have
reached a position such that clearance between contacts is atleast 80% of the
isolating distance.
7.7.
The position of movable contact system (main blades) of each of the Isolators
and earthing switches shall be indicated by a mechanical indicator at the lower
end of the vertical rod of shaft for the Isolators and earthing switch. The indicator
shall be of metal and shall be visible from operating level.
7.8.
The contractor shall furnish the following details along with quality norms, during
detailed engineering stage.
(i) Current transfer arrangement from main blades of isolator along with millivolt
drop immediately across transfer point.
(ii) Details to demonstrate smooth transfer of rotary motion from motor shaft to
the insulator along with stoppers to prevent over travel.
8.0 TEST AND INSPECTION
8.1.
The switches shall be subjected to the following type test in accordance to with
8.2.
8.3.
IS: 9920.
I)
Dielectric test (impulse and one minute) power frequency withstands
voltage.
II) Temperature rise test
III) Rated off load breaking current capacity
IV) Rated active load breaking capacity
V) Rated line charging breaking capacity
VI) Rated short time current
VII) Rated peak withstand current
VIII) Mechanical and Electrical Endurance
The equipment shall be subjected to the following routine test.
I)
Power frequency voltage dry test
II) Measurement of resistance of the main circuit
III) Operating test.
The porcelain will have pull out test for embedded component and beam strength
of porcelain base.
9.0 CONNECTORS
9.1.
Each isolator shall be provided with appropriate number of bimetallic clamping
type connectors as detailed in the schedule of requirement. The maximum length
of jumper that may be safely connected or any special instruction considered
necessary to avoid under loads on the post isolators should be stated by the
tenderer.
10.0
SUPPORTING STRUCTURES
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Technical Specification
10.1. All isolators and earthing switches shall be rigidly mounted in an upright position
on their own supporting structures. Details of the supporting structures shall be
furnished by the successful tenderer. The isolators should have requisite fixing
details ready for mounting them on switch structures.
11.0 PRE-COMMISSIONING TESTS
11.1. Contractor shall carry out following tests as pre-commissioning tests. Contractor
shall also perform any additional test based on specialties of the items as per the
field instructions of the equipment Supplier or Employer without any extra cost to
the Employer. The Contractor shall arrange all instruments required for
conducting these tests along with calibration certificates and shall furnish the list
of instruments to the Employer for approval.
(a) Insulation resistance of each pole.
(b) Manual operation and interlocks.
(c) Insulation resistance of control circuits and motors.
(d) Ground connections.
(e) Contact resistance.
(f) Proper alignment so as to minimise to the extreme possible the vibration
during operation.
(g) Measurement of operating Torque for isolator and Earth switch.
(h) Resistance of operating and interlocks coils.
(i) Functional check of the control schematic and electrical & mechanical
interlocks.
(j) 50 operations test on isolator and earth switch.
12.0
TECHNICAL DATA SHEET FOR ISOLATORS
SL
Technical Particulars
Isolators class
No.
33 kV
11kV
1
Nominal system voltage, kV
33
11
2
Highest system voltage, kV
36
12
3
Rated frequency, Hz.
50
50
4.
Type of Isolator
Double Break,
Double Break,
center pole
center pole
rotating
rotating
5
Rated continuous current, A
630
630/400 A
6
Rated short time current, kA
25
16
for 3sec
7
Rated duration of short time
3
3
current, Second
8
Rated lightning impulse
withstand voltage, kV (peak)
i) To earth & between poles
170
95
ii) Across isolating distance
170
95
9
Rated 1 minute power
frequency withstand voltage,
kV (rms)
70
28
i) To earth & between poles
80
40
ii) Across isolating distance
10
Minimum creepage distance
of insulators, mm
900
400
11
Temperature rise
As per relevant IS
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Technical Specification
3.8
TECHNICAL SPECIFICATION OF OUTDOOR CURRENT AND
POTENTIAL TRANSFORMERS
1.0 SCOPE OF CONTRACT
1.1.
This Section of the Specification covers general requirements for design,
engineering, manufacture, assembly and testing at manufacturer‘s works of
33kV and 11 kV outdoor Current and Potential Transformers.
2.0 STANDARDS
2.1.
The equipment covered by this specification shall, unless otherwise stated
be designed, constructed and tested in accordance with the latest revisions of
relevant Indian Standards and shall conform to the regulations of local statutory
authorities.
2.2.
In case of any conflict between the Standards and this specification, this
specification shall govern.
2.3.
The current transformer shall comply also with the latest issue of the
following Indian standard.
(i)
IS: 2705(Part- Current transformers: General requirement.
I)
(ii)
IS: 2705(Part- Current transformers : Measuring Current
II)
transformers
(iii)
IS: 2705(Part- Current transformers : Protective Current
III)
transformers
(iv)
IS: 2705(Part- Current transformers: Protective Current
IV)
transformers for special purpose application.
(v)
IS: 3156(Part- Potential transformers: General requirement.
I)
(vi)
IS: 3156 (Part- Potential transformers : Measuring Potential
II)
transformers
(vii) IS: 3156 (Part- Potential transformers : Protective Potential
III)
transformers
3.0 GENERAL REQUIREMENTS
3.1.
The cores of the instrument transformers shall be of high grade, non-aging
CRGO steel of low hysteresis loss and high permeability.
3.2.
Instrument transformers shall be of Dead Tank design or Live Tank design.
3.3.
The instrument transformers shall be truly hermetically sealed
POLYCRETE Type
3.4.
A complete leak proof secondary terminal arrangement shall be provided
with each instrument transformers, secondary terminal shall be brought into
weather, dust and vermin proof terminal box. Secondary terminal boxes shall be
provided with facilities for easy earthing, shorting, insulating and testing of
secondary circuits. The terminal boxes shall be suitable for connection of control
cable gland.
3.5.
All instrument transformers shall be of single phase unit.
3.6.
The instrument transformers shall be so designed to withstand the effects
of temperature, wind load, short circuit conditions and other adverse conditions.
3.7.
All similar parts, particularly removable ones, shall be interchangeable with
one another.
3.8.
All cable ferrules, lugs, tags, etc. required for identification and cabling shall
be supplied complete for speedy erection and commissioning as per approved
schematics.
3.9.
The instrument transformers shall be designed to ensure that condensation
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Technical Specification
of moisture is controlled by proper selection of organic insulating materials
having low moisture absorbing characteristics.
3.10.
All steel work shall be degreased, pickled and phosphated and then applied
with two coats of Zinc Chromate primer and two coats of finishing synthetic
enamel paint.
4.0 COMMON MARSHALLING BOXES
4.1.
The outdoor type common marshalling boxes shall conform to the latest
edition of IS 5039 and other general requirements specified hereunder.
4.2.
The common marshalling boxes shall be suitable for mounting on the steel
mounting structures of the instrument transformers.
4.3.
One common marshalling box shall be supplied with each set of instrument
transformers. The marshalling box shall be made of sheet steel and weather
proof. The thickness of sheet steel used shall be not less than 3.0 mm. It is
intended to bring all the secondary terminals to the common marshalling.
4.4.
The enclosures of the common marshalling boxes shall provide a degree of
protection of not less than IP 55 (As per IS 2147).
4.5.
The common marshalling boxes shall be provided with double hinged front
doors with pad locking arrangement. All doors and removable covers and plates
shall be sealed all around with neoprene gaskets or similar arrangement.
4.6.
Each marshalling box shall be fitted with terminal blocks made out of
moulded non-inflammable plastic materials and having adequate number of
terminals with binding screws washers etc. Secondary terminals of the
instrument transformers shall be connected to the respective common
marshalling boxes. All out going terminals of each instrument transformer shall
terminate on the terminal blocks of the common marshalling boxes. The terminal
blocks shall be arranged to provide maximum accessibility to all conductor
terminals.
4.7.
Each terminal shall be suitably marked with identification numbers. Not
more than two wires shall be connected to any one terminal. At least 20 %
spare terminals shall be provided over and above the required number.
4.8.
All terminal strips shall be of isolating type terminals and they will be of
minimum 10 A continuous current rating.
4.9.
All cable entries shall be from bottom. Suitable removable gland plate shall
be provided on the box for this purpose. Necessary number of cable glands
shall be supplied fitted on to this gland plate. Cable glands shall be screw on
type and made of brass.
4.10.
Each common marshalling box shall be provided with two numbers of
earthing terminals of galvanised bolt and nut type.
4.11.
All steel, inside and outside work shall be degreased, pickled and
phosphated and then applied with two coats of Zinc Chromate primer and two
coats of finishing synthetic enamel paint. The colour of finishing paint shall be as
follows: 4.12.
i) Inside:
Glossy White
4.13.
ii)
Outside:
Light Grey (Shade No. 697 of IS: 5)
5.0 TESTS
5.1.
Routine/Acceptance Tests (all units)
5.2.
All routine tests shall be carried out in accordance with relevant Standards.
All routine/acceptance tests shall be witnessed by the Employer/his authorised
representative.
5.3.
Type Tests: The bidder shall furnish type test certificates and results for the
all tests as per relevant Standards along with the bid for current and potential
transformers of identical design.
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Technical Specification
5.4.
Type test certificates so furnished shall not be older than 5 (five) years as
on date of Bid opening.
6.0
NAME PLATES
6.1.
All equipment shall have non-corrosive name plates fix at a suitable
position indelibly mark with full particular there on in accordance with the
standard adapted.
7.0
MOUNTING STRUCTURES
7.1.
All the equipment covered under this specification shall be suitable for
mounting on steel structures. Supply of mounting structures is also in the scope
of this tender.
7.2.
Each equipment shall be furnished complete with base plates, clamps, and
washers etc. and other hardware ready for mounting on existing steel
structures.
8.0
SAFETY EARTHING
8.1.
The non-current carrying metallic parts and equipment shall be connected
to station earthing grid. For this two terminals suitable for 40mm X 10mm GI
strip shall be provided on each equipment.
9.0 TERMINAL CONNECTORS
9.1.
The equipment shall be supplied with required number of terminal
connectors of approved type suitable for ACSR/XLPE cable. The type of
terminal connector, size of connector, material, and type of installation shall be
approved by the Employer, as per installation requirement while approving the
equipment drawings.
10.0 PRE-COMMISSIONING TESTS
10.1.
Contractor shall carry out following tests as pre-commissioning tests.
Contractor shall also perform any additional test based on specialties of the
items as per the field instructions of the equipment Supplier or Employer without
any extra cost to the Employer. The Contractor shall arrange all instruments
required for conducting these tests along with calibration certificates and shall
furnish the list of instruments to the Employer for approval.
10.2.
Current Transformers
(i) Insulation Resistance Test for primary and secondary.
(ii) Polarity test.
(iii) Ratio identification test - checking of all ratios on all cores by primary
injection of current.
(iv) Dielectric test of oil (wherever applicable).
(v) Magnetising characteristics test.
(vi) Tan delta and capacitance measurement
(vii) Secondary winding resistance measurement
(viii) Contact resistance measurement (wherever possible/accessible).
10.3.
11.0
Potential Transformers
(i)
Insulation Resistance test for primary (if applicable) and secondary
winding.
(ii) Polarity test.
(iii) Ratio test
(iv) Dielectric test of oil (wherever applicable).
(v) Tan delta and capacitance measurement of individual capacitor stacks.
(vi) Secondary winding resistance measurement.
TECHNICAL
DATA
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SHEET
FOR
CURRENT
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POTENTIALTRANSFORMERS
11.1.
For 33 kV/11kV CTs the instrument security factor at all ratios shall be less
than 2.5 for metering core.
11.2.
TYPE AND RATING:
All instrument transformer shall be outdoor type, single phase, polycrete type
suitable for mounting on steel structure. The instrument transformer shall have
the following ratings and particulars.
Item
SL
Ratings and Particulars
No
33 KV
11 KV
.
A
Nominal system voltage
33 kV
11 kV
B
Highest system voltage, kV
36
12
C
Rated frequency ,HZ
50
50
D
System earthing
Solidly earth
Solidly earth
E
Insulation level
a) Impulse withstand voltage: kVp
170
70
b) One minute p.f. Withstand voltage, kV
70
28
(r.m.s.)
F
Short time current for one second, kA
16
12.5
G Minimum creepage distance, mm
900
360
H
Temperature rise
As per ISS
As per ISS
J
TRANFORMER C.T.
(i) No. of Cores
3
3
(ii) Transformation ratio
200-100/5-5- 600-300/5-5-2.89A
5A
(iii) Rated out put
(a) Core-1
30 VA
30 VA
(b) Core-2
15 VA
15VA
(C) Core-3
(iv) Accuracy class
(a) Core-1
0.5
0.5
(b) Core-2
5P
5P
(C) Core-3
PS
PS
(v) Accuracy limit factor
(a) Core-1
(b) Core-2
10
10
(C) Core-3
(v) Instrument security factor
(a) Core-1
Less than 5
Less than 5
(b) Core-2
(C) Core-3
(v) Minimum Knee point voltage,
Volts
(C) Core-3
100 Volts
100volts
FEEDER CT
(i) No. of Cores
2
2
(ii) Transformation ratio
400-200/5-5-5
400-200/5-5
(iii) Rated out put
(a) Core-1
30 VA
30 VA
(b) Core-2
15 VA
15 VA
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Technical Specification
Item
SL
No
.
(iv) Accuracy class
(a) Core-1
(b) Core-2
(v) Accuracy limit factor
(a) Core-1
(b) Core-2
(v) Instrument security factor
(a) Core-1
(b) Core-2
POTENTIAL TRANSFORMER
(a) Core Burden
Ratings and Particulars
33 KV
11 KV
0.5
5P
0.5
5P
10
10
<=5
33kV/√3
/110V/√3
30 VA
<=5
11kV/√3 /110V/√3
30 VA
(b) Accuracy class
0.5
05
(c) Rated voltage factor
1.2
1.2
Note:
(i) It is intended to use different ratios of the same CT at the same time for
differential protections and metering cores. The CTS should therefore be
suitable for the above purpose by secondary tapings only. The ratio change
by secondary taps is acceptable as long as the required CT specifications
are achieved at all ratios.
(ii) The knee point voltage specified above shall be at higher ratio/ taps.
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Technical Specification
3.9
TECHNICAL SPECIFICATION FOR 33kV & 11kV LIGHTNING
ARRESTORS
1.0
2.0
SCOPE
This Section covers the specifications for design, manufacture, shop &
laboratory testing before despatch of 33 kV and 11 kV 10 kA, Station class heavy
duty, gapless metal (zinc) oxide Surge Arrestors complete with fittings &
accessories.
3.0
STANDARDS
 The design, manufacture and performance of Surge Arrestors shall comply with IS:
3070( Part-3 )/1993 unless otherwise specifically specified in this Specification
4.0
GENERAL REQUIREMENT
The surge arrestor shall draw negligible current at operating voltage and at the same
time offer least resistance during the flow of surge current.
The surge arrestor shall consist of non-linear resistor elements placed in series and
housed in electrical grade porcelain housing/silicon polymeric of specified creepage
distance.
The assembly shall be hermetically sealed with suitable rubber gaskets with effective
sealing system arrangement to prevent ingress of moisture.
The surge arrestor shall be provided with line and earth terminals of suitable size. The
ground side terminal of surge arrestor shall be connected with 25x6 mm galvanized
strip, one end connected to the surge arrestor and second end to a separate ground
electrode. The bidder shall also recommend the procedure which shall be followed in
providing the earthing/system to the Surge Arrestor.
The surge arrestor shall not operate under power frequency and temporary over
voltage conditions but under surge conditions, the surge arrestor shall change over to
the conducting mode.
The surge arrestor shall be suitable for circuit breaker performing 0-0.3sec.-CO-3minCO- duty in the system.
Surge arrestors shall have a suitable pressure relief system to avoid damage to the
porcelain/ silicon polymeric housing and providing path for flow of rated fault currents in
the event of arrestor failure.
The reference current of the arrestor shall be high enough to eliminate the influence of
grading and stray capacitance on the measured reference voltage.
The Surge Arrestor shall be thermally stable and the bidder shall furnish a copy of
thermal stability test with the bid.
The arrestor shall be capable of handling terminal energy for high surges, external
pollution and transient over voltage and have low losses at operating voltages.










5.0
ARRESTOR HOUSING
 The arrestor housing shall be made up of silicon polymeric housing and shall be
homogenous, free from laminations, cavities and other flaws of imperfections that
might affect the mechanical and dielectric quality. The housing shall be of uniform
brown colour, free from blisters, burrs and other similar defects.
Arrestors shall be complete with insulating bases, surge counters with leakage current
meters (33 KV LA) and terminal connectors.
 The housing shall be so coordinated that external flashover shall not occur due
to application of any impulse or switching surge voltage up to the maximum design
value for arrestor. The arrestors shall not fail due to contamination. The arrester
housings shall be designed for pressure relief class as given in Technical Parameters
of the specification.
 Sealed housings shall exhibit no measurable leakage.
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Technical Specification
6.0
FITTINGS & ACCESSORIES
 The surge arrestor shall be complete with insulating bases, surge counters with
leakage current meters (for 33 KV LA) and terminal connectors.
 The terminals shall be non-magnetic, corrosion proof, robust and of adequate size and
shall be so located that incoming and outgoing connections are made with minimum
possible bends. The top metal cap and base of surge arrestor shall be galvanized. The
line terminal shall have a built in clamping device which can be adjusted for both
horizontal and vertical takeoff.
7.0
SURGE MONITOR
 A self-contained discharge counter suitably enclosed for outdoor use and requiring no
auxiliary or battery supply for operation shall be provided for each single pole unit.
Leakage current meter with suitable scale range to measure leakage current of surge
arrestor shall also be supplied within the same enclosure. The number of operations
performed by the arrestor shall be recorded by a suitable cyclometric counter and
surge monitor shall be provided with an inspection window. There shall be a provision
for putting ammeter to record the current/alarm contacts in the control room if the
leakage current exceeds the permitted value. Similar provision shall be considered for
surge counter also.
 Surge monitor shall be mounted on the support structure at a suitable height so that the
reading can be taken from ground level through the inspection window and length of
connecting leads up to grounding point and bends are minimum.
 Surge monitor shall have to be provided for 33 KV class only.
8.0
TESTS
 Test on Surge Arrestors
The Surge Arrestors offered shall be type tested and shall be subjected to routine and
acceptance tests in accordance with IS: 3070 (Part-3). In addition, the suitability of the
Surge Arrestors shall also be established for the following:
-
Residual voltage test
Reference voltage test
Leakage current at M.C.O.V
P.D. test
Sealing test
Thermal stability test
Aging and Energy capability test
Watt loss test
Each metal oxide block shall be tested for guaranteed specific energy capability in
addition to routine/acceptance test as per IEC/IS.
 The surge arrestor housing shall also be type tested and shall be subjected to routine
and acceptance tests in accordance with IS: 2071.
 Galvanization Test
All Ferrous parts exposed to atmospheric condition shall have passed the type tests
and be subjected to routine and acceptance tests in accordance with IS: 2633 & IS
6745.
9.0
NAME PLATE
 The name plate attached to the arrestor shall carry the following information:
Rated Voltage
Continuous Operation Voltage
Normal discharge current
Pressure relief rated current
Manufacturers Trade Mark
Name of Sub-station
Year of Manufacturer
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Technical Specification
Name of the manufacture
Purchase Order Number along with date
10.0
11.0
PRE-COMMISSIONING TESTS
 Contractor shall carry out following tests as pre-commissioning tests. Contractor shall
also perform any additional test based on specialties of the items as per the field
instructions of the equipment Supplier or Employer without any extra cost to the
Employer. The Contractor shall arrange all instruments required for conducting these
tests along with calibration certificates and shall furnish the list of instruments to the
Employer for approval.
1. Operation check of LA counters.
2. Insulation resistance measurement.
3. Capacitance and Tan delta measurement of individual stacks.
4. Third harmonic resistive current measurement (to be conducted after energisation.
TYPE AND RATINGS
SL
No.
1
2
3
4
5
6
7
9
10
Particulars
Rated voltage of arrester, kV
Rated frequency, Hz
Nominal discharge current of arrester,
kA
Maximum residual voltage at nominal
discharge current, kV (peak)
Maximum steep current impulse
residual voltage at kV (kVP)
One minute power frequency withstand
voltage of arrester insulation, kV (rms)
1.2 / 50  second impulse withstand
voltage of arrester insulation, kV (peak)
Line discharge class
Insulator Housing
a) Power frequency withstand test voltage
(wet) (kV rms)
b) Lightning impulse withstand tests
voltage(KVp)
c) Pressure Relief Class
d) Creepage distance not less than (mm)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Voltage class
33 kV
11 kV
30
9
50
50
10
10
108
40
130
50
70
28
170
95
2
2
70
28
170
95
40
900
40
400
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Technical Specification
3.10 TECHNICAL SPECIFICATION OF 33 KV AND 11 KV GANG
OPERATED SWITCH
1.0
SCOPE
1.1. This specification is intended to cover design manufacture, testing at
manufacturer‟s works, transport to site, insurance, storage, erection and
commissioning of 33 KV and11 KV gang operated switch (Isolators) with
all fittings and accessories.
1.2.
The Isolators are for outdoor installation suitable for both vertically
and horizontally mounting on mounting structures or M.S. Channel and for
use at sectionalizing/tapping points of 33 KV lines and at 33/11 KV substations.
1.3.
33 KV isolators shall be supplied with Earth Switch as and where
specified
1.4.
The successful bidders shall supply the necessary drawings and
instructions for installation and commissionning of the Isolators.
2.0
CONSTRUCTIONAL DETAILS
2.1.
The vertically mounted gang switches shall be manually operated triple
pole type with single break operation. The operation of the equipment shall be
through forward and backward motion of the mid-pole post insulator. The
contacts shall be made of silver faced hard drawn copper.
2.2.
The horizontally mounted switches, with or without earth switches shall
have rotating blade features and pressure reliving features. Such isolators are
required to be double break; three posts per phase, single through, gang
operated three phase type. All isolators with/without earth switch shall operate
through 900 from their fully closed position to fully open position
2.3.
The switch shall be fitted with arcing horns and the horns shall be easily
replaceable.
All isolators shall be provided with suitably rated terminal connectors to directly
receive ACSR conductor of required size. The termination shall have at least 3
pairs of holes to hold the conductor tight with nuts & bolts The terminals shall
conform to all the test requirements of IS: 5561 and shall be designed as to
avoid bimetallic corrosion.
2.4.
The operating rod shall comprise of not less than 40 mm (nominal bore)
Galvanised steel pipe as per IS 1161-1979. The length of the operating rod shall
be suitable for operation as per installation methods. The rod shall be so
threaded that the length can be adjusted.
2.5.
The horizontal operation shaft shall be of solid Galvanised steel of square
section suitable for fitting the insulator base of the switch. Length of the rod shall
be such as to maintain the phase clearance as per I.S.
2.6.
The operating handle shall have OFF/ON locking arrangement and
provision for earthing the equipment.
2.7.
The gang operating switch shall be provided with three post insulators per
phase conforming to IS 5350 (Pt-III)-1971. The cast iron post shall be
embedded in the insulators with sulphur cement. For embedded components,
pull out strength should be such as to result in breakings of the porcelain
insulators, the beam strength shall be as per relevant T.S. Creepage distance
shall not be less than 900 mm and 300 mm for 33KV and 11 KV isolators
respectively.
2.8.
All similar materials and removable parts of similar equipments shall be
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Technical Specification
interchangeable with each other.
3.0
3.1.
APPLICABLE STANDARD
Unless otherwise stipulated in this specification, the Gang operated switch
shall conform to IS. 9920 (Pt-I to Pt-IV).
4.0
Failure to meet guarantees and requirement of specification
4.1.
If after installation, the operation of the switch proven to be unsatisfactory,
to the purchaser, the tenderer shall have to take back or replace.
5.0
TEST AND INSPECTION
5.1.
The switches shall be subjected to the following type test in accordance to
with IS: 9920.
IX) Dielectric test (impulse and one minute) power frequency withstands
voltage.
X) Temperature rise test
XI) Rated off load breaking current capacity
XII) Rated active load breaking capacity
XIII) Rated line charging breaking capacity
XIV) Rated short time current
XV) Rated peak withstand current
XVI) Mechanical and Electrical Endurance
5.2.
The equipment shall be subjected to the following routine test.
IV) Power frequency voltage dry test
V) Measurement of resistance of the main circuit
VI) Operating test.
5.3.
The porcelain will have pull out test for embedded component and beam
strength of porcelain base.
5.4.
The manufacturer shall afford the inspection representing the purchaser
or third party nominee all reasonable facilities, with charge, to satisfy him that
the material is being furnished in accordance with this specification.
The purchaser has the right to have the test carried out at his own cost by an
independent agency whenever there is dispute regarding the quality of supply.
6.0
GUARANTEE
The Bidder shall offer equipment performance guarantee for a minimum
period of year from the date of commissioning.
Any damaged part or defective part of the equipment, the bidder has to replace
at his cost.
7.0
TECHNICAL SPECIFICATION
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Technical Specification
1.0
1.1
1.2
1.3
SYSTEM DETAILS
Nominal system voltage, KV
Highest system voltage, KV
Nominal frequency, Hz
2.0
2.1
2.2
2.3
GENERAL SPECIFICATION
Rated voltage, KV
Rated frequency, Hz
Rated normal current, Amp
2.4
Rated lightning impulse withstand
voltage
i) To earth and between pole, KV 170
75
(Peak)
ii) Across the isolating distance, KV 195
(Peak)
Power frequency one minute
withstand voltage,
i) To earth and between pole, KV 70
28
(RMS)
80
ii) Across the isolating distance, KV
(RMS)
Temperature rise
-as per relevant
ISRated short time current 3 Sec, KA
25
16
Rated active load break capacity, 400
200
Amps
Transformer OFF-Load current
10
10
breaking capacity, Amps
Rated line changing breaking
6.3
6.3
capacity, A(rms)
Rated Peak withstand current
25 KA
16
Electrical endurance
20 operations for
400 A ,200
operation
for 200 A
Mechanical endurance
1000 operation
Minimum insulator creepage distance, 900
300
mm
2.5
2.6
2.7
2.8
2.9
2.10
2.11
2.12
2.13
2.14
33
36
50
11
12
50
36
50
400 A,
800
12
50
630,
3.11 TECHNICAL SPECIFICATION OF BATTERY BANK
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Technical Specification
1.0
SCOPE
This Section of the Specification covers the design, manufacture, and testing at
manufacturer‘s work, of stationary type sealed, Valve Regulated Lead Acid
Battery Bank, Battery Charger, complete with all required accessories for various
Sub-stations.
2.0
BATTERY BANK
2.1
TECHNICAL PARTICULARS OF BATTERY BANK
1.
Battery Rating
2.
Type of battery
3.
Battery specification
4.
5.
Manufacturers cell designation
No of Cells
6.
Cycle life of Battery @ 27⁰ C
7.
8.
9.
All efficiency
WH Efficiency
Self discharge/ Week
Max, allowable ambient temp at
10.
which cell can safely operate
11. Overall dimension of each cell
12. Overall weight of each cell
13.
Recommended Max period of
storage
14. Material of container
15. Type of separator
16. Type of +ve & -ve plates
17. Material of rack
Method of connection between
18.
cells
19. Recommended float charge
20. Recommended boost charge
Time required for boost charge
21. from fully discharged condition
at 27⁰ C
22. Voltage ripple allowable
23. Type of connectors
110 V-100 Ah to 1.75 ECV at C10 at 27⁰ C
Maintenance free valve regulated lead acid
(MF-VRLA) battery
Batteries conforms to IS 15549:2005
Also conforms to International
Standards (I) IEEE 1188 and 1189
(II) BS6290 Part 4/ IEC 896
F 100 P
55 Nos.
2000 cycles for 50 % depth of discharge or
1200 cycles for 80 % depth of discharge
Above 90%
Above 80 %
< 1% of rated capacity
55⁰ C continuously and 70⁰ C short time
(107.8 x 198.5 x 477)mm approx.
27 kg approx.
6 months from the date of manufacturing
and the batteries shall be stored in covered
area at 27⁰ C
Polypropylene co-polymer
Highly absorbent micro porous spun glass
matrix (AGM)
Flat pasted
Mild steel coated with acid resistance paint
Bolted
Batteries shall be charged in constant
potential mode with current limit
Voltage: 2.23-2.25 Volts per cell
Current: Recommended- charging current
is 45 amps
Voltage: 2.3 Volts per cell
Current: Recommended- charging current
is 45 to 90 amps
9 Hrs for 90 % state of charge
(or)
24 hrs for 100 % state of charge
< 2% of the RMS value
Lead coated heavy duty copper strips
2.1.1 PLATES
Positive plates shall be made of flat pasted type using lead-cadmium antimony
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Technical Specification
alloy for durability, high corrosion resistant, maintenance free, long life both in
cyclic as well as in ,float applications.
Negative plates shall be heavy duty, durable flat plate using lead calcium alloy
pasted box grid. Negative plates shall be designed to match the life of positive
plates and combination of negative and positive plates shall ensure long life,
durability and trouble free operation of battery.
PLC operated equipment should be deployed for preparation of paste to ensure
consistency in paste quality. Conventional / manual type of paste preparation is
not allowed.
2.1.2 CONTAINER AND LID
The containers and lids shall be made of a special grade polypropylene
copolymer plastic material. They shall be sufficiently robust and not liable lo
deformation under internal operating pressures and within the temperature range
naturally encountered, leak proof, non-absorbent and resistant to the acid with
low water vapour permeability.
2.1.3 VENT PLUGS :
Each cell shall be equipped with one-way safety valve with opening pressure of
5±1 psi and closing pressure 4±1 psi. The vent plug shall be made with suitable
grade of fire retardant plastic material. Each valve opening shall be covered with
flame barrier capable in preventing the ingress of flame into the cell interior when
the valve opens and hydrogen / oxygen gas mixture is released.
2.1.4 SEPARATORS :
Separator shall be made of spun glass, micro porous matrix and shall be
resistant to Sulphuric Acid. It shall be capable of keeping the entire electrolyte
and shall be electrically insulated. Sufficient separator overlap and PVC shield
protection to top and bottom edges of the plates is to be provided to prevent
short circuit formation between the edges of adjacent plates.
2.1.5 CONNECTORS :
The connectors shall be lead coated copper of suitable size to join the cells. The
connectors shall be suitably designed and coated to withstand corrosion due to
sulphuric acid. The coating should be adequate and tenacious. All the copper
inter cell connectors shall be provided with heal shrinkable sleeves except at the
connecting points.
2.1.6 ELECTROLYTE:
The electrolyte shall be prepared from the battery grade Sulphuric Acid
confirming to ISS: 266. The batteries shall be supplied in factory filled and
charged condition.
2.1.7 WATER
Water required for preparation of electrolyte shall conform to IS: I069.
2.1.8 PLATE CONNECTION
Lugs of plates of like polarity shall be connected by lead burning to a horizontal
strap having an upstanding terminal post adopted for connection to external
circuit. Strap and post shall be caste with lead alloy. The positive and negative
terminal posts shall be clearly marked for unmistakable identification.
2.1.9
BOLTS AND NUTS
Nuts and Bolts for connecting the cells shall be of superior grade passivated
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Technical Specification
Stainless steel.
2.1.10
TERMINALS
Terminals shall be of integral lead terminal with solid copper core with M6
threading for fastening. The junction between terminal posts and cover and
between the cover and container shall be hermetically sealed.
2.1.11
BATTERY RACKS
Batteries shall be installed on MS racks to be supplied by the Contractor to fit in
the battery room. Racks/Trays shall be powder coated with anti corrosive paint.
Rack shall accommodate 55 cells plus 2 spares. Racks/Tray shall be suitably
treated before painting for protection against fungus growth and other harmful
effects due to tropical environment.
The colour of the supporting racks shall conform to RAL 7032 shade.
a) cy H.V. test / Insulation tests.
3.12 ECHNICAL SPECIFICATION OF STEEL STRUCTURES RS JOIST
(GALVENISED)
1.0 SCOPE:
1.1. This specification calls for manufacture, stage testing, inspection and testing
before dispatch, packing and delivery of R.S. Joists (Galvenised), 175x85mm
and 150x80mm.
1.2. The materials shall conform, in all respect, to the high standard of design and
workmanship and shall be capable of performing duties specified herein.
Materials offered shall be complete in all respect.
2.0 STANDARDS:
2.1. Materials shall conform to the latest applicable Indian standards. In case bidders
offer Steel Section and supports conforming to any other international
specifications which shall be equivalent or better than IS, the same is also
acceptable.
sn
1
Standard
IS 2062
IS 2062
IS:1852
Title
Specification for R.S. Joists, M.S. Channels, M.S.
Angles & M.S. Flats
Chemical and physical composition of material
Rolling and cutting tolerances for Hot rolled steel
products.
2.2. In the paragraph above relevant Indian standards specification have been
mentioned. However, the material meeting any other authoritative international
standards, which ensures equal or better quality than the standards, mentioned
shall also be acceptable. Material for which Indian Standards are not available,
the relevant British standards and IEC recommendations will be applicable.
Photocopy of all such standards according to which the materials have been
offered should be attached.
:
3.0 CLIMATIC CONDITIONS:
The Steel Sections to be supplied against this specification shall be suitable for
satisfactory continuous operation under the following tropical conditions:4.0 LENGTH:4.1. The materials to be supplied shall be in the following lengths:
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Technical Specification
4.2. (i) R.S. Joists 175x85 mm 9 meters to 11 meters
(ii) R.S. Joists 150x80 mm 1.5 meters
Any tolerance on negative or positive side shall not be accepted.
5.0 CHEMICAL COMPOSITION AND PHYSICAL PROPERTIES OF R.S. JOISTS
5.1. C H E M I C A L C O M P O S I T I O N
SN
CHEMICAL COMPOSITION FOR
Fe 410 WA GRADE
C
0.23% MAX.
Mn
1.5% MAX
S .
0.050% MAX
P
0.050% MAX.
SI .
0.40% MAX
CE
0.42% MAX
(Carbon Equivalent)
.
5.2. M E C H A N I C A L P R O P E R T I E S
SN
Tensile strength (min.)
1.
2.
3.
4.
5.
6.
42 Kgf/mm2 or 410
N/mm2
Yield stress Min. for thickness/diameter
< 20 mm
- 26 kgf/mm2 OR 250
N/mm2
20 – 40 mm
- 24 kgf/mm2 OR 240
N/mm2
> 40 mm
- 23 kgf/mm2 OR 230
N/mm2
Elongation %( min.)
- 23%
Bend test (internal Dia)
Min-3 t
(t – is the thickness of
the material)
6.0 MARKING:6.1. It is desirable that the manufacture should put his identification marks on the
finished materials. The mark shall be in legible English letters given with
marking dies of minimum 18 mm size at the Interval of 3 meter mentioned as ―
APDCL‖
7.0 INSPECTION AND TEST CERTIFICATE:
7.1. The materials to be supplied will be subject to inspection and approval by the
representative of Employer. The Bidder is required to offer the finished material
for inspection well in advance to the Employer.
7.2. The BILLETS/INGOTS from which materials shall be re-rolled and supplied to
us shall be of tested quality as per IS: 2830/6914 (Latest revision) respectively
and shall be arranged from their own source. The chemical composition and
physical properties of the finished materials shall be as per relevant
specification.
7.3. The materials shall be tested in ISI approved Laboratory of the approved
Manufacturer having all facilities available for conducting all the tests as
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prescribed in relevant ISS. The Employer may get the material tested in the
accredited laboratory by NABL. The testing charges whatsoever shall be to the
Bidder‘s account.
7.4. The Bidder is required to specifically indicate that the approved manufacturer:(i) Holds valid ISI License against respective ISS.
(ii) That the materials offered shall bear ISI certification marks.
(iii)
Is required to submit a copy of the valid ISI License clearly indicating size
and range of roll-able product against respective ISS.
8.0 GUARANTEED TECHNICAL PARTICULARS OF R.S Joists
8.1. Guaranteed Technical Particulars are to be furnished along with the bid.
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3.13 TECHNICAL SPECIFICATION FOR EXECUTION OF WORK (FOR
33KV AND 11 KV LINES)
1.0
SCOPE : ERECTION OF 33 KV AND LINES WITH 9.75 M PSC POLES
The scope covers the survey of the proposed route, tree clearance wherever
necessary transport of materials to the locations, erection of the line testing of the
line and handing over to the APDCL as per specification. Materials such as steel,
cement, PSC Poles, top cleats, clamps, washers, earth wires, HBG metal, sand,
water, cost of bolts and nuts etc., as given in Annexure-1 are to be procured by the
contractor cost of which shall be included in the bid.
1.1
General :
The Contractor should be well acquainted with the IE Rules 1956 as amended from
time to time and with the Indian Telegraph Act 1889 so that necessary provisions
therein may be followed.
1.2
ELECTRICAL CLEARANCE
As per Indian Electricity Rules, 1956 ( amended version )
Sl. Particulars
33 KV line
No.
1
Minimum height of any
6.4 metres
conductor of an overhead line
across any street
2 Minimum
height
of
any
6.1 metres
conductor of an overhead line
along any street
3 Minimum height of any
5.2 metres
conductor (bare )of an
overhead line erected
elsewhere
4 Minimum height of any
4.0 metres
conductor (insulated )of an
overhead line erected
elsewhere
5 Minimum Clearance of an 3.7mtr. (vertical )
overhead line from building
2.0 mtr. (
horizontal)
6 Clearance between over-head
2.130 meters
line and communica-tion line
7 Minimum
Clearance
from
0.270 meters
another line
8 Phase to phase clearance (
1370 mm
min)
9 Span
50 m
10 Minimum clearance between
6.1
LT line with 11 KV & 33 KV
1.3
11 KV Lines
6.2
SURVEY OF THE ROUTE
The Tentative route map of the line to be erected will be furnished by the APDCL to
the Contractor along with the copy of the concluded agreement.
The Contractor is required to carry out the detailed survey of the route of the line
and fix up the locations at the average span indicated in the schedule and mark the
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locations and submit a detailed route map to the Engineer in charge of the work
within 30 days for approval. In the course of surveying by the contractor, any
conspicuous variations in the change and physical feature to those indicated in the
route map and as actually existing are noticed, the deviations must be brought to
the notice of the APDCL Engineer. The APDCL Engineer if considered necessary
shall make alterations, which shall be carried out accordingly and the APDCL after
inspecting the surveyed route and the revised route map shall be given for final
approval in writing. The contractor shall not commence the work until the final
approval of the route map is given by the Engineer in charge in writing to the
contractor.
1.4
WAY LEAVES AND TREE CUTTINGS
Proposals for way leaves and right of way shall be submitted by the contractor.
Permission will be obtained by the APDCL within reasonable time for which due
notice shall be given by the Contractor. The Contractor shall arrange for tree
cutting or tree branches cutting also.
The widths of tree clearance to be adopted for lines of various voltages are as
detailed below:
1.4.1
33 KV LINE (Trunk Line)
All growth within 6.096 M (20 ft) from the center line of support and all trees
which may fall and foul the line.
1.4.2 The Contractor shall take all possible steps to see that standing crops, etc. are
not damaged while attending to tree cutting. When such damage is inevitable the
compensation will be borne by the APDCL provided the damage is with the prior
concurrence of the Engineer. The Contractor shall bear the compensation for
damage caused by the gangs without prior concurrence of the Engineer
concerned.
1.4.3 No trees shall be cut until the APDCL has made necessary arrangement with the
authorities concerned and permission is given to the Contractor to fell such
trees. The contractor shall arrange to remove the obstacles as soon as possible.
1.4.4 At such times, when it may not possible for APDCL, to arrange right-of-way for
excavation of pole pits or erecting the poles of stringing the line, then at all such
times, the contractor shall shift his gangs to other areas. The rates quoted shall
cover all such contingencies and no extra payments shall be claimed for such
contingencies.
1.5
EXCAVATION OF POLE PITS, STAY PITS AND D.P. PITS
1.5.1 After the final survey of the line and after marking the pole locations with pegs,
excavation work has to be commenced in accordance to the approved route
map. Excavation is generally done by pick axes, crow V-bars and showers
although some times earth augers are used. Excavation of pole pits in very hard
or rocky soil or in rock beds, may involve blasting with suitable explosives. The
pits for the supports are excavated in the direction of the line as this will facilitate
the erection of support are excavated in the direction of the line as this will
facilitate the erection of support, in addition to giving greater lateral stability, the
depth of the foundation to be excavated for poles shall be in accordance with
relevant sketch for the erection of pole or stay of D.P. etc.
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1.6 ERECTION OF POLES :
1.6.1 PSC POLE :
PSC poles should be erected perpendicular to ground level including excavation
of earth pit having depth equal to 1/5 th the length of pole and cross-section 75
cm x 50 cm as directed by department including dragging and carrying of pole to
site as per soil condition as given below.
(i) earth filling with soil at bottom and surrounding with vigorous ramming;
(ii) earth filling with soil at bottom and surrounding with vigorous with boulder
packing including supply of boulder by contractor ( size of boulder 150mm x
200mm);
(iii) grouting and mufflering in proportion 1:2:4 RCC foundation and filling of
cement concrete as per specification including supply of cement , stone
chips, shuttering etc. as directed ]
1.6.2 POLE CLAMP:
The pole clamp is to be made of MS flat of size 40 mm x 6 mm with necessary
drilling of holes and painting with primer and anti corrosive paint suitable for
different size of steel tubular pole and PSC pole.
1.7
ERECTION OF SUPPORTS
After the excavation of pits is completed the supports to be erected may be brought
to the pits location. Then the pole may be erected inside the pit. Wooden support
may be utilized to facilitate lifting of the pole at the pit locations.
Before the pole is put into pit, RCC padding may be laid below the pole to increase
the surface contact between the pole and the soil. The padding will distribute the
weight of the pole uniformly on the soil.
Having lifted the pole, the same should be kept in a vertical position with the help of
manila rope of 25 mm dia using the rope as a temporary anchor.
As the poles are being erected say from the pole already erected to the next
location where the pole is being erected, the alignment of the poles are to be
checked and set right by visual check. The verticality‘s of the poles are to be
checked with a spirit level on both transverse and longitudinal directions.
Having satisfied that the verticality and alignment are all right, earth filling or
concreting is to be done.
In swampy and special locations, however, before earth filing, the poles are to be
concreted up to ground level of the pit.
After the poles have been set the temporary anchors are to be removed. The
supports shall be buried to a depth as per REC construction standard.
1.8
ERECTION OF D.P. STRUCTURES FOR ANGLE LOCATIONS (FOR 33
LINES):
Generally, for angles of deviation more than 20° double pole structures of spacing
1.2 mts (4.0 ft) may be erected. The pits are to be excavated as per bisection of the
angle of deviation.
After the poles are erected, the horizontal / cross bracing should be fitted and the
supports held in a vertical position with the help of temporary guys of manila rope of
at least 25 mm dia. Ensuring that the poles are held in a vertical position (this can
be checked with a spirit level) the concreting of the poles with cement, granite chips
of size 20/30 mm mesh and sand in the ratio M400 conforming to ISS is to be done
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from the bottom of the support to the ground level. Before lifting the pole in the pit,
concrete padding of not less than 75 mm thickness may be put for the distribution
of the load of the support on the soil.
After the concreting is done, the pit may be filled with earth after curing of the
concrete is completed.
Four stays along the line, two in each direction and two stays along the bisection of
angle of deviation are to be provided.
Stay concreting may be done with M 400 concrete mixture
The D.P. shall be erected as per the approved drawing.
1.9
ANCHORING AND PROVIDING GUYS FOR SUPPORTS
Fitting of stay set on overhead line including digging of earth pit of area 90cm x
60 cm and depth of 1.4 m placing the stay rod with G.I stay wire Guy insulator on
pole clamp , fixing of thimble bow etc with hard soil packing and ramming to fill up
pit to ground level.
Guys are to be provided to the supports at the following places (i) Angle locations,
(ii) Dead end locations, (iii) Tee-off points, (iv) Steep gradient locations to avoid
uplifted on the poles.
The installation of guy will involve the following works:
i) Excavation of pit and fixing of stay rod.
ii) Fastening guy wire to the support.
iii) Tightening guy wire and fastening to the anchor
The marking of the guy pit for excavation, the excavation of pits and setting of the
anchor rod must be carefully carried out. The stay rod should be placed in the
position such that the angle of inclination of the rod with the vertical face of the
point is 30°/45° as the case may be. The concreting of the stay at the bottom
should then be carried out. The back filling and ramming must be well done
thereafter, and allowed to set for at least 7 days. The free end of the guy wire is
passed through the eye of the anchor rod, bent back parallel to the main portion of
the guy and bound after inserting the G.I. Thimble. The loop is protected by the G.I.
Thimble, where it bears on the anchor rod. Where the existence of guy wire proves
hazardous, it should be protected with suitable asbestos pipe, filled with concrete of
about 2 mts length above the ground level, duly painted with white and black stripe
so that it may be visible at night. The turn buckle shall be mounted at the pole end
of the stay and guy wire so fixed that the eye bolt turn buckle is half way in the
working position, thus giving the maximum movement for tightening or loosening.
Guy insulators are placed to prevent the lower part of the guy from becoming
electrically energized by a contact of the guy when the conductors snap and fall on
them of due leakage. No guy insulator shall be located less than 2.6 mts. from the
ground.
The anchoring and providing guys for supports (Single guy Bow guy fly guy) shall
be done as per sketch enclosed. Bow guy and fly guy shall be provided as per field
conditions.
HT GUY INSULATOR
Power
line
Voltage
Designation
of Insulator
Dry one minute
Wet one
power
minute power
frequency
frequency
withstand
withstand
voltage
voltage
33 KV
C
27 KV ( r.m.s)
13 KV ( r.m.s)
[ for 33 KV , 2 insulators to be used in series]
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Minimum
failing load
88 KN
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Technical Specification
1.10 FIXING OF CROSS ARMS INSULATORS
After the erection of supports and providing guys, the next step would be to mount
the cross arms on the support erected. The lineman should climb the support having
requisite tools with him and the cross arm is then tied to a hand line and pulled up
by the ground man and should station himself well to one side so that if any
material drops from the top of the pole it may not strike him. All the materials
required should be lifted or lowered by means of the hand line. In no case, the
materials of the tools should be dropped or thrown from the pole top.
The fixing of 33 KV Cross arms shall be in accordance to spacing detailed in
Sketch. G.I. bolts and nuts and spring washers of good quality only shall be used
which will have to be procured by the contractor.
1.11 Back Clamps
The back clamps for fixing of the seating channels, ―V‖ cross arms, horizontal cross
arms and top cleats will have to be procured by the contractor and shall be in
accordance with sketch enclosed and the clamp shall be fabricated with 75 X 8 mm
M.S. Flat for 33 KV
1.12 Top Cleats
The top cleats shall be got fabricated with M.S. Channel of size 75 X 40 mm for 33
KV and shall be in accordance with REC construction standard
1.13 INSULATORS
The pins for insulators shall be fixed in the holes provided in the cross arms and the
pole top brackets. The insulators shall be mounted in their places over pins and
tightened. In the case of strain or angles supports, where strain fittings are provided
for this purpose, one strap of the strain fitting is placed over the cross arm before
placing the bolts in the hole of the cross arms. The nut of the strap is so tightened
that the strap can move freely in horizontal direction, as this is necessary to fix the
strain insulator.
The insulator shall be cleaned and examined for defects before fixing, it shall be
ensured that all the current carrying parts are smooth and without dirt, cracks or
chips.
Disc Insulator Strings
Each insulator string shall consist of following numbers of Disc Insulator units.
Sl .No
Type of
No of Disc Insulator Unit No of Disc Insulator Unit
String
for 33 KV
for 11 KV
1.
Suspension
3
2.
Tension
4
1.14 STRINGING OF THE LINE CONDUCTORS
For the guidance of the contractor certain do‘s and don‘ts are given below before
the workmen actually commence the stringing work.
1.14.1 Do‟s and Don‟ts
DO‟s
ii.
iii.
iv.
Use proper equipment for handling aluminum conductors at all
times.
Use skids, or similar method for lowering reels or coils from
transport or ground.
Examine reel before unreeling for presence of nails or any other
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object, which might damage the conductor.
v.
Rotate the reel or coil while unwinding conductor.
vi.
Grip all strands while pulling out the conductor.
vii.
Control the unreeling speed with suitable braking arrangement.
viii.
Use wooden guards of suitable braking arrangement.
ix.
Use long straight, parallel jaw grip with suitable liners when pulling
conductor thus avoiding nicking or kinking of the conductor.
x.
Use free running sleeves or blocks with adequate grooves for
drawing/paving conductors.
xi.
Use proper sag charts.
xii.
Mark conductors with crayons or adhesive tape of such (other)
material, which will not damage the strand.
xiii.
Make all splicing with the proper tools.
xiv.
Use a twisting wrench for twisting the joints.
xv.
Chromite or graphite conducting oxide-inhibiting grease should be
used before cleaning with wire brush.
DON‟Ts
i.
Do not handle conductors without proper tools at any stage.
ii.
Do not pull conductors without ensuring that there are no
obstructions on the ground.
iii.
Do not pull out excess quantity of conductor than is required.
iv.
Do not make jumper connections on dirty or weathered conductor.
v.
Do not handle aluminum conductors in a rough fashion but handle
it with care it deserves.
1.14.2
CONDUCTOR ERECTIONS
The erection of overhead line conductor is a very important phase in
construction. The erection of conductors can be sub-divided into 4 separate parts
as follows:
i.
Transport of conductors to work site.
ii.
Paving and stringing of conductors.
iii.
Tensioning and sagging of conductors.
iv.
Joining of conductors.
At the important crossing of roads, canals, navigable rivers, railways etc.,
flagmen should be in attendance to ensure that normal services are not unduly
interrupted. These crossing should only be carried out in conjunction with and
with the approval of the proper authorities concerned.
The conductor drums shall be transported to the tension point without injuring
the conductor, if, it is necessary to roll the drum on the ground for a small
distance, it should be slowly rolled in the direction of the marked on the drum.
The drum should be so supported that it can be rotated freely. For this purpose
the drum should either be mounted on the cable drum supports of jacks or hung
by means of chain pulley of suitable capacity, suspended from a tripod. In case if
it is not possible to raise the conductor drum by any of the above method, a
trench of suitable depth slightly bigger than the conductor drum may be dug, so
as to facilitate free rotation of the cable drum when it is suspended in the trench
by means of M.S. Shaft. While paving, care should be taken to see that
conductor does not rub against any metallic fitting of the pole or on the bad/rocky
ground. Wooden trusses should be used for this purpose to support the
conductor. The conductor should be passed over the poles on wooden or
aluminum snatch pulley blocks provided with low friction bearings. While
conductor is being paved out slowly, some braking arrangement should be made
so that the rotation of the drum may be stopped in emergency.
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In case the length of one piece of the conductor is less than the length of the
section in which conductor paving is being done, it is easy to stretch one length
of all phases from one end the remaining length from another end of the section
any part of the conductor shall be left at a height of less than that of 5 meters,
above the ground by rough sagging.
1.14.3 Mid Span Jointing of Conductors
The mid span jointing of conductors should be carried by sleeves and twisting
the joint at the ends and the wire should project a few centimeter, beyond the
end of the sleeves. The projected wires are given a sharp bend to keep them
from slipping out of the sleeve. The end of the sleeves are then held tightly by
twisting wrenches and then 4 to 5 turns in one direction generally anti-clock wise
direction. Crimping Tools are preferably to be used for joints and jumpers.
1.14.4 SAGGING AND TENSIONING
On the completion of the paving of the conductors and making mid span joints if
any, tensioning operations will commence. Temporary guys will have to be
provided for both the anchoring supports in the section where the stringing has
to be done. At the tensioning end, one of the conductors is pulled manually up to
a certain point and then come along clamp is fixed to the conductor to be
tensioned. The grip to the come along clamp is attached to double sleeve pulley
block or the pulley lift machine and gradually tensioned.
The conductor should then be sagged in accordance with the sag temperature
chart for the particular conductor and span. The sag should then be adjusted in
the middle span of the section. The sag chart is to be provided. The stretch of
the conductor has to be taken out before stringing in order to avoid the gradual
increase in sag due to the setting down of the individual wires. There are ways of
accomplishing this:
a) Pre-stressing
In this method the conductor is pulled up to tension considerably above the
correct figures, but never exceeding 50% of breaking load for a short period of
say twenty minutes. As this method requires more time and involves the use of
stronger tackle to secure the higher tension the other method of over tensioning
is commonly adopted.
b) Over-tensioning
This method consists of pulling up the conductor to a tension a little above the
theoretical tension for prevailing temperature and fixed it up at that tension with
correspondingly reduced sag. After a certain time the conductor will settle down
to the correct sag and tension. A tension of five to eight percent more than the
theoretical value has been found to be suitable for the sizes of ACSR and AAAC
conductors standardized by REC. The ambient temperature during sagging may
be recorded correctly.
Conductors can be sagged correctly only when the tension is the same in each
span throughout the entire length of section. Use of snatch blocks reduces the
friction and chances of inequality of tension in various spans.
Sagging can be accomplished by several different methods but most commonly
used method is ―Slighting‖. The slighting sag method of measuring sag is by the
use of targets placed on the supports below the cross arms. The targets may be
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light strip of wood clamped to the pole at a distance equal to the sag below the
conductor when the conductor is placed in snatch block. The lineman sees the
sag from the next pole. The tension of the conductor is then reduced or
increased, until the lowest part of the conductor in the span coincides with the
lineman‘s line of sight.
When sagging is completed, the tension clamps shall be fixed. The clamp can be
fitted on the conductor without releasing the tension. A mark is made on the
conductor at a distance from the cross-arm equal to the length of complete strain
insulator. Before the insulator set is raised to position, all nuts should be free.
Come along clamp is placed on the conductor beyond the conductor clamp and
attached to the pulling unit. The conductor is pulled in sufficiently to allow the
insulator assembly to be fitted to the clamp. After the conductor is clamped to
insulator, assembly unit may be released gradually.
If the tension is released with a jerk, an abnormal stress may be transferred to
conductor and support, which may result in the failure of the cross arm, stay or
pole in some cases. After the stringing is completed, all poles, cross arms,
insulators, fittings etc. are checked upto ensure that there have been no
deformities etc.
The next step is to place the conductor on the top of the pin insulator from the
snatch block and removing snatch blocks. Conductors are then fastened to
insulator by the use of aluminum wires. The following points should be observed:
i)
Proper size of the tie binding wire which can be readily handled and with
adequate strength is to be used.
ii)
The length of tie wire should be sufficiently long for making complete tie
including the end allowances for gripping with ends.
iii)
A good tie should provide a secure binding between the line conductor
and insulator and should reinforce the conductor on either side of the
insulator.
iv)
The use of cutting pliers for binding the tie wire should be avoided.
v)
The tie wire which has been used previously should be reused
Before tying the conductor to the insulator two layers of Aluminum tapes should
be wrapped over the conductor in the portion where it touches the insulator. The
width and thickness of aluminum tape to be used for a specific size of
conductors has been specified in hand books of aluminum conductor
manufacturers and the same be referred to. The Aluminum tapes should also be
used at the tension clamp and for proper grip.
Normally in straight runs of line, the conductors are run on the top of insulators.
When there is small of deviation the conductor is placed inside groove and
bound. Accordingly, there are two methods of tying the conductors to insulators.
The binding wire/tie wire has to be procured by the contractor and the bid price
shall include the cost of this.
The contractor shall be entirely responsible for any damage to the supports,
other accessories and conductor. He shall also be responsible for proper
distribution of the conductor drums to keep number and lengths of cut pieces of
the conductor to a minimum.
1.14.5 CONDUCTOR DAMAGE AND REPAIR
If the conductor is damaged for whatever reasons, and damage is not repaired
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by aluminum sleeves, etc., it shall be brought to the notice of the Engineer and
shall not be used without his approval. Even repairing of conductor surfaces
shall be done only in case of minor damages, scuff marks etc., which are safe
from both electrical and mechanical points of view. The final; conductor surface
shall be clean, smooth, without any projection sharp points, cut or abrasion etc.
giving satisfactory corona and R.I. performance.
No joints or splice be made in span‘s crossing over main roads, railways, small
rivers or intension spans. Not more than one joint per conductor shall be allowed
in one span. The strength of the joint shall conform to IE Rule 75.
1.14.6 STRINGING.
Whatever necessary ground clearances have to be measured to ensure obtaining
adequate line clearance as per IE Rule 77 (i)
GUARDING :
 When an overhead line crosses or is in proximity of any telecommunication
line arrangement shall be made to provide protective device or guarding.
 When an overhead line crosses or is in proximity of to another over head line
or overhead lines of different voltage on same supporting structure guarding
arrangement shall be provided so as to guard against the possibility of their
coming into contact with each other.
 Every guard-wire shall be an actual breaking strength of not less than 635 kg
and if made of iron or steel shall be galvanize.
 Every guard-wire shall be connected with earth at each point at which its
electricity continuity is broken.
1.15 EARTHING
1.15.1 PIPE EARTHING
At D.P Locations, Pits are to be excavated the steel and metal parts are to be
earthed by pipe earthing as per the drawing or sketch enclosed to this
specification. Duly filling the pits with finely broken coke having granule sizes not
more than 25 mm thick. The coke shall be maintained up to a distance of 300
mm for the pipe on all sides. The top edge of the pipe shall be at least 200 mm
below the ground level. The CI strips shall be fixed not less than 300 mm deep
from the ground level.
The tenders shall quote the charges for earthing inclusive of the cost of coke,
excavation and back filling.
1.15.2 Pole Earthing: All Supports shall be properly earthed.
1.16 CONCRETING
The cement concrete used for the foundations shall be of M 400 grade.
The full concreting for the poles if erected in excavated act shall be done so that
the complete block will be of dimensions( 0.6 X 0.6 X 1.6) + 0.2 X 0.2 Mtr. (0.6 X
0.6 X 1/35) + 0.2 X 0.2 X 0.2 Mtrs. so as to maintain as exposed portion for 0.2
Mtrs height above the ground level.
If augur is used for making pole pits, ramming shall be done after erection of
pole.
1.17 WORKMANSHIP
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The contractor shall entirely be responsible for correct erection of all support as
per the approved drawings, and their correct setting and alignment, as approved
by the engineer. If the supports and D.P. structures after the erection are found
to differ from approved route maps and drawings or to be out of alignment, the
contractor shall dismantle and re-erect them correctly at his own cost without
extension of time. The supports must be truly vertical and in plumb after erection
and no straining will be permitted to bring them to vertical position. Verticality of
each support shall be measured by the contractor and furnished to the Engineer.
1.18 Location numbers for each pole shall be painted on the pole.
1.19 Anti-climbing devices, and danger boards are to be provided at all railway
crossings and road crossings. No extra charges shall be admissible even though
separate gangs may have to be sent by the contractor for fitting these
accessories and attachments on the support at the appropriate time.
1.20 FINAL CHECKING, TESTING AND COMMISSIONING
After the completion of the work final patrolling and checking of the line shall be
done by the contractor to ensure that all foundations work, pole erection and
stringing have been done as approved by the Engineer, and also to ensure that
they are completed in all respects. Contractor shall prepare pole schedules and
hand it over to the Engineer. All works shall be thoroughly inspected keeping in
view of the following main points.
i)
Sufficient back filled earth is lying over each foundation pit and it is
adequately compacted.
ii)
Concreting and coping of poles are in good and finally shaped conditions.
iii)
All the accessories and insulators are strictly as per drawings and are free
from any defects or damages, what-so-ever.
iv)
All the bolts and nuts should be of G.I material and as per contractual
provisions.
v)
The stringing on the conductor has been done as per approved sag and
desired clearances are available.
vi)
No damage, minor or major to the conductor, earth wire, accessories and
insulator strings still unattended are noticed.
vii)
For all points double jumpers shall be provided to each phase. The
jumpers provided at the cut points are connected rigidly to the tension
hardware utilizing all the jointing bolts provided for the purpose.
The contractor shall submit a report to the above effect to the Engineer. In case,
it is noticed later that some or any of the above are not fulfilled the Engineer will
get such items rectified through other agencies and recover the cost of such
works from the bills payable to the contractor against that contract or any other
contract executed by him for APDCL.
After final checking, the lines shall be tested for insulation in accordance with
tests prescribed by the Engineer. All arrangements for such testing or any other
tests desired by the Engineer shall be done by the Contractor and necessary
labour, transport and equipment shall be provided by him. Any defects found out
as a result of such tests, shall be rectified by the Contractor, forthwith, without
any extra charges to APDCL,.
In addition to the above, the Contractor shall be responsible for testing and
ensuring that the total and relative sags of the conductors are within the
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Technical Specification
specified tolerance. Such tests shall be carried out at selected points along the
route as required by the Engineer and the Contractor shall provide all necessary
equipment and labour to enable the tests to be carried out.
The APDCL, will arrange statutory inspection of the line and indicate the defects
noticed. The Contractor has to rectify all such defects and intimate to APDCL,
Engineer.
After satisfactory tests on the line and an approval by the Engineer the line shall
be energized at full operating voltage before handing over.
1.21 SUPPLY OF CONSTRUCTION MATERIALS BY THE CONTRACTOR
The Contractor has to make his own arrangements for procurement, supply and
use of construction materials like cement, M.S. rounds, HBG metal and sand.
1.22 CEMENT
The contractor has to make his own arrangements for the procurement of
cement to require specifications required for the work subjected to the follows:
a) The contractor shall procure cement, required for the works only from reputed
cement factories (Man producer) acceptable to the Engineer-in-Charge. The
contractor shall be required to be furnished to the Engineer-in –Charge bills of
payment and test certificates issued by the manufacturers to authenticate
procurement of quality cement from the approved cement factory. The contractor
shall make his own arrangement for adequate storage of cement.
b) The contractor shall procure cement in standard packing of all 50 kg per bag
from the authorized manufactures. The contactor shall make necessary
arrangement at his own cost to the satisfaction of Engineer-in-Charge for actual
weighment of random sample from the available stock and shall conform to the
specification laid down by the Indian Standard Institution or other standard
foreign institutions as the case may be. Cement shall be got tested for all the
tests as directed by Engineer-in-Charge at least one month in advance before
the use of cement hags brought and kept on site Godown. Cement bags
required for testing shall be supplied by the contractor free of cost. However, the
testing charges for cement will be borne by the APDCL. If the tests prove
unsatisfactorily, then the charges for cement will be borne by the contractor.
c) The contractor should store the cement of 60 days requirement at least one
month in advance to ensure the quality of cement so brought to site and shall not
remove the same without the written permission of the Engineer-in-Charge.
The contractor shall forthwith remove from the works area any cement that the
Engineer-in-Charge may disallow for use, an account of failure to meet with
required quality and standard.
d) The contractor shall further, at all times satisfy the Engineer-in-Charge on
demand, by production of records and books or by submission of returns and
other proofs as directed, that the cement is being used as rested and approved
by Engineer-in-Charge for the purpose and the contractor shall at all times, keep
his records upto date to enable the Engineer-in-Charge to apply such checks as
he may desire.
e) Cement which has been unduly long in storage with the contractor or
alternatively has deteriorated due to inadequate storage and thus become unfit
for use in the works will be rejected by the department and no claim will be
entertained. The contractor shall forthwith remove from the work area, any
cement the Engineer-in-Charge may disallow for use on work and replace it by
cement complying with the relevant Indian Standards.
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1.23 STEEL
The contractor shall procure mild steel reinforcement bars, high yield strength
deformed(HYSD) bars, rods and structural steel etc. required for the works only
from the main or secondary producers manufacturing steel to the prescribed
specifications of Bureau of Indian Standards or equivalent and licensed to affix
ISI or other equivalent certification marks and acceptable to the Engineer-inCharge. Necessary ISI list certificates are to be produced to Engineer-in-Charge
before use on works. The unit weight and dimensions shall be as prescribed in
the relevant Indian Standard specification for steel. All steel materials shall be
Galvenised.
1.24 INFORMATION AND DATA
a) The information furnished is the best available however, the APDCL does not
guarantee the correctness of interpretations, deductions or conclusions which
are given as supplementary information in the Bid Documents or in any
reports, maps, drawings, diagrams or in other reference information available
to the bidder from APDCL of or otherwise.
The information has been produced as found, communicated to ascertained
or otherwise/learned by the APDCL.
b) it will be the Bidder‘s responsibility to satisfy himself from the ―Reference
Information‖ supplied and or inspection of the site that sufficient quantities of
construction materials required for the works shall exist in the designated
borrow areas or quarry sites.
The APDCL does not accept any responsibility either in handing over the
quarries or procuring the materials or any other facilities. The Tenderer will
not be entitled for any extra rate or claim for the misjudgment on his part for
the quantity and quality of materials available in the quarries.
Failure by the Bidder to have done all the timings which is in accordance with
this condition he is deemed to have done shall not relieve the successful
Bidder of the responsibility for satisfactorily completing the work as required
at the rates quoted by him.
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3.14 TECHNICAL SPECIFICATION FOR PSC POLES [9.75 M]
1.0 SCOPE
This covers design manufacturing, testing at works, transport to site, insurance, storage,
erection and commissioning of PSC poles shall be of solid rectangular with an overall
length of 9.75M suitable for use in overhead 33KV / 11 KV lines
2.0 Applicable Standards
The pre-stressed concrete pole (psc ) shall comply with the relevant provisions
mentioned' in the' following Indian Standards or the latest versions thereof.
a) IS: 1678, Specification for pre-stressed concrete poles for overhead power, traction
and telecommunication lines.
b) IS: 2905, Method of test for concrete poles for overhead power and
telecommunication lines.
c) IS: 7321, Code of Practice for selection, handling and erection of concrete poles for
overhead power and telecommunication lines.
REQUIRED TECHNICAL PARAMETERS FOR 9.75 M PSC POLES
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
4.0
4.1
4.2
5.0
6.0
7.0
Terminology
For the purpose of this specification, following definitions shall apply:
Average Permanent Load
That fraction of the working load which may be considered of long duration over a
period of one year.
Load Factor
The ratio of ultimate transverse load to the transverse load at first crack.
Transverse
The direction of the line bisecting the angle contained by the conductor at the pole. In
the case of a straight run, this will be normal to the run of the line.
Transverse Load at First Crack
For design, the transverse load at first crack shall be taken as not less than the value of
the working load.
Working Load
The maximum load in the transverse direction, that is ever likely to occur, including the
wind pressure on the pole. This load is assumed to act at a point· 600 mm below the
top with the butt end of the pole planted to the required depth as intended in the design.
Ultimate Failure
The condition existing when the pole ceases to sustain a load increment owing to either
crushing of concrete, or snapping of the pre-stressing tendon or permanent stretching of
the steel in any part of the pole.
Ultimate Transverse Load
The load at which failure occurs, when it is applied at a point 600 mm below the top and
perpendicular to the axis of the pole along the transverse direction with the butt end of
the pole planted to the required depth as intended in the design.
Application
9.75 M PSC Pole
These poles shall be used for 33 kV lines, and for special locations in 11 kV lines, such
as road crossings, etc.
Material
Cement
The cement used in the manufacture of pre-stressed concrete poles shall be ordinary or
rapid hardening Portland cement conforming to IS: 269 (Specification for ordinary and
low heat Portland cement) or IS: 8041 E (Specification for rapid hardening Portland
cement), or high strength ordinary Portland cement conforming to IS: 8112
(Specification of high strength ordinary Portland cement).
Aggregates
Aggregates used for the manufacture of pre-stressed concrete poles shall confirm to IS:
383 (Specification for coarse and fine aggregates from natural sources for concrete).
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The nominal maximum size of aggregates shall in no case exceed 10 mm (for poles
above 9.0 M) and 12 mm (for 7.5 and 8.0 M poles).
8.0
Water
Water should be free from chlorides, sulphates, other salts and organic matter, Potable
water will be generally suitable.
8.1
Admixture
Admixture should not contain Calcium Chloride or other chlorides and salts which are
likely to promote corrosion of pre-stressing steel.
8.2
Pre-stressing Steel
The pre-stressing steel wires including those used as un-tensioned wires (See
Annexure. I, II & III), should conform to IS: 1785 (part-I) (Specification for plain harddrawn steel wire for pre-stressed concrete. Part-I cold drawn stress relieved wire), IS:
1785 (part-II) (Specification for plain hard-drawn steel wire) or IS: 6003 (Specification
for indented wire for pre-stressed concrete). The type designs given in Annexure-I, II
and III are for plain wires of 4 mm diameter with a guaranteed ultimate strength of 175
kg/mm2.
The concrete mix shall be designed to the requirements laid down for controlled
concrete (also called design mix concrete) in IS: 1343 (Code of practice for prestressed concrete) and IS: 456 (Code of practice for plain and reinforced concrete),
subject to the following special conditions:
a) Maximum works cube strength at 28 days should be at least 400 kg/cm2 (for poles
above 9.0 M) and 420 kg/cm2 (for 7.5 and 8.0 M poles).
b) The concrete strength at transfer should be at least 200 kg/cm2 (for poles above 9.0
M) ·and 210 kg/cm2 (for 7.5 and 8.0 M poles).
c) The mix should' contain at least 380 kg of cement per cubic meter of concrete.
d) The mix should contain as Iowa water content as is consistent with adequate
workability. If it becomes necessary to add water to increase the workability, the
cement content also should be raised in such a way that the original value of water
cement ratio is maintained.
9.0
DESIGN REQUIREMENTS
The poles shall be designed for the following requirements:
a) The poles shall be planted directly in the ground with a planting depth as per IS:
1678.
b) The working load on the poles should correspond to those that are likely to come on
the pole during their service life. Designs given in Annexure I,ll and III are for 140 kg,
200 kg, 300 kg, and 400 kg., applied at 0.6 M from top.
c) The factor of safety for all poles above 9.5 M shall not be less than 2.0. For 7.5 M
and 8.5 M poles, the factor of safety shall not be less than 2.5.
d) The average permanent load shall be 40% of the working load.
e) The F.O.S. against first load shall be 1.0.
f) At average permanent load, permissible tensile stress in concrete shall be 30
kg/cm2.
g) At the design value of first crack load, the modulus of rupture shall not exceed 53.0
kg/cm2 for M-400 concrete and 55.2 kg/cm2 for M-420 concrete.
h) At the design value of first crack load, the modulus of rupture shall not exceed 53.0
kg/cm2 for M-400 concrete.
i) The ultimate moment capacity in the longitudinal direction should be at least one
fourth of that il1 the transverse direction.
j) The maximum compressive stress in concrete at the time of transfer of pre-stress
should not exceed 0.8 times the cube strength.
k) The concrete strength at transfer shall not be less than half the 28 days strength
ensured in the design, i.e., 400 x 0.5 = 200 kg/cm2 or 420 x 0.5 = 210 kg/cm2.
10.0 Service Conditions
PSC poles have to be designed to suit the following climatic conditions:
a)
Maximum temperature of air in shade
40°C
b)
Minimum temperature of air in shade
2°C
c)
Maximum temperature of air in sun
45°C
d)
Maximum humidity
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Technical Specification
e)
f)
g)
h)
11.0
12.0
12.1
13.0
14.0
15.0
16.0
Average number of thunder storm days
per
annum
Maximum rainfall per annum
Average rainfall per annum
Wind pressure
45 Days
3500 mm
2200 mm
97.8 Kg/m2
i)
Altitude above MSL
100 to 1000 M
Dimensions and Reinforcements
The cross-sectional dimensions and the details of pre-stressing wires should conform to
the particulars given in Annexure-I, II and III.
The provisions of holes for fixing cross-arms and other fixtures should conform to the
REC standards .
Manufacture
Attire--stressing wires and reinforcements shall be accurately fixed as shown in
drawings and maintained in position during manufacture. The un-tensioned
reinforcement, as indicated in the drawings, should be held in position by the use of
stirrups which should go round all the wires.
AII wires shall be accurately stretched with uniform pre-stress in each wire. Each wire or
a group of wires shall be anchored positively during casing. Care should be taken to see
that the anchorages do not yield before the concrete attains the necessary strength.
Cover
The cover of concrete measured from the outside of pre-stressing tendon shall be
normally 20 Nm.
Welding and Lapping of Steel
The high tensile steel wire shall be continuous over the entire length of the tendon.
Welding shall not be allowed in any case. However, jointing or coupling may be
permitted provided the strength of the joint or coupling is not less than the strength of
each individual wire.
Compacting
Concrete shall be compacted by spinning, vibrating, shocking or other suitable
mechanical means. Hand compaction shall not be permitted.
Curing
The concrete shall be covered with a layer of sacking, canvass, Hessian or similar
absorbent material and kept constantly wet up to the time when the strength of concrete
is at least equal to the minimum strength of concrete at transfer of pre-stress.
Thereafter, the pole may be removed from the mould and watered at intervals to
prevent surface cracking of the unit, the interval should depend on the atmospheric
humidity and temperature.
The pre-stressing wires shall be detensioned only after the concrete has attained the
specified strength at transfer (i.e., 200 or 210 kg/cm2 as applicable). The cubes cast for
the purpose of determining the strength at transfer should be cured, as far as possible,
under conditions similar to those under which the poles are cured. The transfer stage
shall be determined based on the daily tests carried out on concrete cubes till the
specified strength indicated above is reached. Thereafter the test on concrete shall be
carried out as detailed in IS: 1343 (Code of pr3ctice for pre-stressed concrete). The
manufacturer shall supply, when required by the owner or his representative, result of
compressive test conducted in accordance with IS: 456 (Code of practice for plain and
reinforced concrete) on concrete cubes made from the concrete used for the poles. If
the owner so desired, the manufacturer shall supply cubes for test purposes and such
cubes shall be tested in accordance with IS: 456 (Code of practice for plain and
reinforced concrete).
The detensioning shall be done by slowly releasing the wires, without imparting shock
or sudden load to the poles. The rate of detensioning may be controlled by any suitable
means either mechanical (screw type) or hydraulic.
The poles shall not be detensioned or released by cutting the pre-stressing wires using
flames or bar croppers while the wires are still under tension.
Separate eye-hooks or holes shall be provided for handling the transport, one each at a
distance of 0.15 times the overall length, from either end of the pole. Eye-hooks, if
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Technical Specification
provided, should be properly anchored and should be on the face that has the shorter
dimension of the cross-section. Holes, if provided for lifting purposes, should be
perpendicular to the broad face of the pole.
Stacking should be done in such a manner that the broad side of the pole is vertical.
Each tier in the stack should be supported on timber sleeper located as 0.15 times the
overall length, measured from the end. The timber supported in the stack should be
aligned in a vertical line.
Poles should be transported with their broad faces placed vertically and, in such a
manner that the shocks are avoided. Supports should be so arranged that they are
located approximately at a distance equal to 0.15 times the overall length from the
ends. The erection of the pole should be carried out in such a way that the erection
loads are applied so as to cause moment with respect to the major axis, i.e., the rope
used for hoisting the pole should be parallel to the broader face of the pole.
17.0 Earthing
17.1
Earthing shall be provided by having length of 8 SWG GI wire embedded in concrete
during manufacture and the ends of the wires left projecting from the pole to a length of
100 mm at 250 mm from top and 150 mm below ground level.
17.2 Earth wire shall not be allowed to come in contract with the pre-stressing wires.
17.3 Tests
18.0 Transverse Strength Test
Poles made from ordinary Portland cement shall be tested only on the completion of 28
days and poles made from rapid hardening cement only on the completion of 14 days,
after the day of manufacture.
The poles may be tested in either horizontal or vertical position. If tested in horizontal
position, provisions shall be made to compensate for the overhanging weight of the
pole, for this purposed, the overhanging portion of the pole may be supported on a
movable trolley or similar device.
The pole shall be rigidly supported at the butt end for a distance equal to the agreed
depth of planting.
Load shall be applied at a point 600 mm from the top of the pole and shall be steadily
and gradually increased to the design value of the transverse load at first crack. The
deflection at this load shall be measured.
A pre-stressed concrete pole shall be deemed not to have passed the test if visible
cracks appear at a stage prior to the application of the design transverse load for the
first crack.
The load then be reduced to zero and increased gradually to a load equal to the first
crack load plus 10% of the minimum ultimate transverse load, and held up for 2 minutes.
This procedure shall be repeated until the load reaches the value of 80 per cent of the
minimum ultimate transverse load and thereafter increased by 5 per cent of the
minimum ultimate transverse load until failure occurs. Each time the load is applied, it
shall be held for 2 minutes. The load applied to pre-stressed concrete pole at the point
of failure shall be measured to the nearest five Kilograms.
The pole shall be deemed not to have passed the test if the observed ultimate
transverse load is less than the design ultimate transverse load.
19.0 Measurement of Cover
After completion of the transverse strength test, the sample pole shall be taken and
checked for cover. The cover of the pole shall be measured at 3 points, one within 1.8
meter from the butt end of the pole. the ·second within 0.6 meters from the top and the
third at an intermediate point and the mean value compared with the specified value.
The mean value of the measured cover should not differ by more than (±) 1 mrn from
the specified cover. The individual values should not differ by more than (±) 3 mm from
the specified value.
If these requirements are not met, the workmanship with reference to aligning of the
end plates and pre-stressing wires and assembly of moulds should be improved and
inspection at pre-production stage tightened suitably.
20.0
MARKING
The pole shall be clearly and indelibly marked with the following particulars either during
or after manufacture but before testing at a position so as to be easily read after
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Technical Specification
erection in position.
a) Month and year of manufacture
b) Transverse strength of pole in Kg
c) Maker's serial No and mark and Project .
21.0
SL
NO
1
INSPECTION
Inspection may be carried out by the purchaser or third party nominee at any stage of
manufacture. The supplier shall grant free access to the purchaser's representative or
third party nominee at a reasonable time when the work is in progress. Inspection and
acceptance of any equipment under this specification by the purchaser shall not relieve
the supplier of his obligation of furnishing equipment in accordance with the
specification and shall not prevent subsequent rejection if the equipment is found
defective.
ITEM
Type of Pole
PARAMETERS
9.75 M
P.S.C pole
9.75 Mts.
1.8 Mts.
350 mm
175 mm
120 mm
4 mm
22 Nos of
4mm dia.
175 KG /
SQMM
1865 kg /
wire
As per IS :
1343 /1960
21.45 KG
3
4
5
6
7
8
9
Length of pole
Depth of Plantation
Bottom Depth
Top Depth
Breath
Diameter of pre-stressing wire
No. of tensioned wire per pole
10
11
Minimum Ultimate Tensile
strength of 4 MM HT wire
Minimum initial pull of 4 mm wire
12
Spacing HT wires
13
14
Quantity of HT wire/ pole
Link & spiral
15
M.S spiral
16
17
18
19
20
21
22
Maximum Aggregate size
Total weight per pole
Minimum clear cover
Factor of safety
Concrete grade
Ultimate Load
Earthing shall be provided by 4
MM dia. Galvanized iron wire
embedded in concrete
23
one marks to be provided at
at 1.8 M
ground level
28 days cube strength of concrete 420 KG
( Min) as per IS : 456/2000.
SQ.CM
24
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8.5 M PSC
Pole
8.5 Mts.
1.5 Mts.
300 mm
162 mm
112 mm
4 mm
16 Nos of
4mm dia.
175 KG /
SQMM
1865 kg /
wire
As per IS :
1343 /1960
13.60 KG
7.5 M P.S.C
pole
7.5 Mts.
1.5 Mts.
250 mm
140 mm
105 mm
4 mm
12 Nos of 4mm
dia.
175 KG / SQMM
1750 kg / wire
As per IS : 1343
/1960
9.0 KG
4 nos ,5 mm in 4 nos ,5 mm in
bottom & 4 nos bottom & 4 nos
,5 mm in top )
,5 mm in top )
3.540 KG ( 4
nos ,5 mm in
bottom & 4
nos ,5 mm in
top
3 mm dia of
150 c/c
12 mm
750 KG
20 mm
2.5
M-420
675 KG
3 mm dia of 3 mm dia of 150
150 c/c
c/c
12 mm
12 mm
550 KG
360 KG
20 mm
20 mm
2.5
2.5
M-420
M-420
500 KG
350KG
Projecting
from the pole
at length of 50
MM at 215
from top & 150
MM below
ground level
Projecting from
the
pole
at
length of 50 MM
at 215 from top
&
150
MM
below
ground
level
Projecting from the
pole at length of 50
MM at 215 from
top & 150 MM
below ground level
At 1.5 M
At 1.25 M
/ 420 KG
SQ.CM
/ 420KG/SQ.CM
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3.15 TECHNICAL SPECIFICATION FOR STEEL TUBULAR
POLES(GALVENISED) FOR OVERHEAD LINES
1.0 SCOPE :
1.1 This specification covers the general requirements towards design, manufacture, testing at
manufacturers works, supply and delivery for tubular steel poles of circular cross section (
swaged type ) for overhead lines.
2.0 STANDARD :
2.1. The tubular steel poles shall conform to the latest edition of Indian Standard
specification
 IS: 2713 ( Part – I, III ) : 1980 Specification for Steel Tubular poles

The Steel Tubular Poles conforming to other internationally accepted,
which ensure equal or higher quality than the standards, mentioned above also
be acceptable. In case the bidder who wish to offer material conforming to the
other standards, salient points of difference between adopted and specific
standards with authentic English Translation shall be furnished.
3.0 Topography and Climatic Condition :
3.1. The materials offered, shall be suitable for operation in tropical climate and will be
subjected to the sun and inclement weather and shall be able to withstand wide range
of temperature variation. For the purpose of design, average atmospheric temperature
may be considered to be 50 °C with humidity nearing saturation.
4.0 Materials :
4.1. The materials used in construction of tubular steel poles shall be of the tested quality
of steels of minimum tensile strength 540 MPa ( : 55 Kgf/mm2 ). Or 410MPa as the
case may be.
4.2. The materials, when analysed in accordance with IS : 228 ( Part-III : 1972 ) and
IS : 228 ( Part-IX) shall not show sulpher and phosphorous contents of more
than 0.060
percent each.
5.0 Types, Size and construction :
5.1. Tubular Steel Poles shall be swaged type.
5.2. Swaged poles shall be made of seamless or welded tubes of suitable lengths swaged
and jointed together. No circumferential joints shall be permitted in the individual tube
lengths of the poles. If welded tubes are used they shall have one longitudinal weld
seam only : and thelongitudinal welds shall be staggered at each swaged joint.
5.3. Swaging may be done by any mechanical process. The upper edge of each joint shall
be chamfered if at an angle of about 45o. The upper edge need not be chamfered if a
circumferential weld is to be deposited in accordance with clause No. 5.3 2 of IS: 2713 (
Part-I) :1980.
5.4. The length of joints on swaged poles shall be in accordance with clause No. 5.4 of IS:
2713(Par-I): 1980.
5.5. Poles shall be well-finished, clean and free from harmful surface defects. Ends of the
poles shall be cut square. Poles shall be straight, smooth and cylindrical. The weld
joints, if any, shall be of good quality, free from scale, surface defects, cracks, etc.
5.6. Tolerances for outside diameter, thickness, length, weight and straightness shall be in
accordance with IS: 2713 (Part-I) : 1980.
5.7. The poles shall be GALVENISED and coated with black bituminous paint conforming to
IS : 158-1968 throughout, internally and externally, upto the level which goes inside the
earth.
6.0 Earthing Arrangements :
6.1. For earthing arrangement a through hole of 14mm diameter shall be provided in each
pole at a height of 300mm above the planting depth.
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Technical Specification
7.0 PRINCIPAL PARAMETERS
SN
ITEM DESCRIPTION
PARAMETERS
PARAMETER
PARAMETERS
1.
Type of Pole
SP-76
SP-66
SP-60
2.
Overall Length
14.5 M
12.0 M
12.0 M
3.
Planting Depth
2.0 M
2.0 M
2.0 M
4.
Load Applied from
top at a distance of
0.60 M
0.60 M
0.60 M
5.
Height above
ground
12.5 M
10.0 M
10.0 M
6.
Length of sections
Bottom
a. a
6.5 M
5.80 M
5.80 M
Middle
b.
4.0 M
3.10 M
3.10 M
Top
c.
4.0 M
3.10 M
3.10 M
7.
Outside Diameter &
thickness of section
a
Bottom, MM
219.1 x5.90
219.1 x5.90
165.1 x 5.40
b
Middle ,MM
193.7 x4.85
193.7 x4.85
139.7 x 4.50
c
Top,MM
165.1 x 4.5
165.1 x 4.5
114.3 x 3.65
8.
Approx. Wt of pole
380 KG
322 KG
208 KG
9.
crippling load
514 kgf
650 kgf
333 kgf
10.
breaking load
724 kgf
916 kgf
469 kgf
11.
Ultimate tensile
strength
410 MPa ( 42
KGf / mm2 )
410 MPa ( 42
KGf / mm2 )
410 MPa ( 42
KGf / mm2 )
12.
Base Plate
A Mild Steel
base plate of
size 400 mm x
400 mm x 8
mm shall be
welded at the
bottom of the
pole.
A Mild Steel
base plate of
size
400×400×8
mm shall be
welded at the
bottom of the
pole.
A Mild Steel base
plate of size
400×400×8 mm
shall be welded
at the bottom of
the pole.
13.
Painting
The complete
pole shall be
Galvenised as
per IS 2629
and the inner
side & outer
underground
The complete
pole shall be
Galvenised
as per IS
2629 and the
inner side &
outer
underground
The complete
pole shall be
Galvenised as
per IS 2629 and
the inner side &
outer
underground
portion of the
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
portion of the
pole is to be
painted with
black
bituminous
paint
conforming to
IS : 158-1968
throughout,[
internally and
externally, up
to the level
which goes
inside the
earth.
portion of the
pole is to be
painted with
black
bituminous
paint
conforming
to IS : 1581968
throughout,[
internally and
externally, up
to the level
which goes
inside the
earth.
pole is to be
painted with
black
bituminous
paint
conforming to
IS : 158-1968
throughout,[
internally and
externally, up to
the level which
goes inside the
earth.
8.0 Tests and Test Certificates :
8.1. The following tests shall be conducted on finished poles :
A. Tensile test and chemical analysis for sulpher and phosphorous ,
B. Deflocation test,
C. Permanent set test, and
D. Drop test.
8.2. In addition to above verification of dimensions as per IS : 2713 (Part-III) : 1980 shall be
carried out during acceptance of lots.
8.3. Number of poles selected for conducting different tests shall be in accordance to
clause No.10.1.1 and No. 10.1.12: of IS: 2713 (Part-I) 1980.
8.4. Tests shall be carried out before supply of each consignment at the manufacturers
woks and test certificates should be submitted to the purchaser for approval prior to
delivery.
8.5. Re-tests, if any, shall be made in accordance with IS: 2713 (Part-I) 1980.
8.6. Purchaser reserves the right to inspect during manufacturing and depute his
representative to inspect/test at the works.
8.7. If any extra cost is required for carrying out the above specified tests, the same shall
be borne by the tenderer.
9.0 Marking :
9.1. The poles shall be marked with designation, manufacturer‘s identification, year of
manufacture and name of the purchaser: APDCL
9.2. The poles may also be marked with the ISI certification mark if applicable.
10.0
Performance :10.1.
The bidder shall furnish a list of the major supplies effected during the last 3
(three) years indicating the volume of supply and actual delivery dates alongwith the
bids.
10.2.
Bids may not be considered if the past manufacturing experience is found to be
less that 3 (three) years.
11.0
Deviation :-
13.1 Any deviation in technical specification shall be clearly indicated with sufficient
reasons thereof. Purchaser shall however reserve the right to accept and/or
reject the same without assigning any reasons what-so-ever.
12.0 Guaranteed technical particulars :
12.1.
The tenderer shall furnish all necessary guaranteed technical particulars in the
prescribed proforma enclosed hereinafter.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
Annexure „B‟
TECHNICAL GUARANTEED AND OTHER PARTICULARS.
(To be filled in by the Tenderer)
1. Type of Pole offered
2. a) Whether tubes are of seamless
constn. Or welded type.
b) Is it manually welded tubes? If so,
state name/address of manufacturer
c) It is ERW tubes? If so, state
name/address of manufacturer
3. Overall length
4. Effective length of section
a) Bottom
b) Middle
c) Top
5. Effective dia thickness of section
a) Bottom
b) Middle
c) Top
6. Approximate weight (Kg.)
7. Breaking Load (Kg.)
8. Working Load (Kg.)
9. Weight/Mtr.
i) Top Section (kg)
ii) Middle Section (kg)
iii) Bottom Section (kg)
10. Crippling load (kg)
11. Load for permanent set
12. Load for temporary deflection
13. Joint length
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
3.16 TECHNICAL SPECIFICATION FOR GALVANIZED CHANNEL
CROSS ARMS
1.0
3.0
SCOPE :
This specification covers the design, manufacture, testing at manufacturer's
works, transport to site, insurance, storage, erection and commissioning of
Galvanized Cross Arm and channel used for 33KV, 11 KV & line complete with all
accessories as specified.
Standards
The M.S Cross Arm and channel supplied under this specification shall conform the latest
issue of the relevant Indian Standards IS – 226:1975, Regulations etc. except where
specified otherwise.
The rolling and cutting tolerance for steel product conforming to IS: 266 shall be
those specified in the IS: 1852-1973 with latest revision.
Galvanization conforming to latest version of 1S:2629
In the event of conforming to any standards other than the Indian Standards, the salient
features of comparison shall be clearly set out separately
3.0 GENERAL REQUIREMENT :
i. The cross arm shall be fabricated grade of mild steel of channel section as per
requirement.
ii. All steel members and other parts of fabricated material as delivered shall be free of
warps, local deformation, unauthorized splices, or unauthorized bends.
iii. Bending of flat strap shall be carried out cold. Straightening shall be carried out by
pressure and not by hammering. Straightness is of particular importance if the
alignment of bolt holes along a member is referred to its edges.
iv. Holes and other provisions for field assembly shall be properly marked and cross
referenced. Where required, either by notations on the drawing or by the necessity
of proper identification and fittings for field assembly, the connection shall be match
marked.
v. A tolerance of not more than 1mm shall be permitted in the distance between the
center lines of bolt holes. The holes may be either drilled or punched and, unless
otherwise stated, shall be not more than 2mm greater in diameter than the bolts.
vi. When assembling the components force may be used to bring the bolt holes
together (provided neither members nor holes are thereby distorted) but all force
must be removed before the bolt is inserted. Otherwise strain shall be deemed to
be present and the structure may be rejected even though it may be, in all other
respects, in conformity with the specification.
vii. The back of the inner angle irons of lap joints shall be chamfered and the ends of
the members cut where necessary and such other measures taken as will ensure
that all members can be bolted together without strain or distortion. In particular,
steps shall be taken to relieve stress in cold worked steel so as to prevent the onset
of embitterment during galvanizing.
viii. Similar parts shall be interchangeable.
ix. Shapes and plates shall be fabricated and assembled in the shop to the greatest
extent practicable. Shearing flame cutting and chipping shall be done carefully,
neatly and accurately. Holes shall be cut, drilled or punched at right angles to the
surface and shall not be made or enlarged by burning. Holes shall be clean-cut
without torn or ragged edges, and burrs resulting from drilling or reaming operations
shall be removed with the proper tool.
x. Shapes and plates shall be fabricated to the tolerance that will permit fielderection
within tolerance, except as otherwise specified. All fabrication shall be carried out in
a neat and workmanlike manner so as to facilitate cleaning,
painting, galvanizing and inspection and to avoid areas in which water and
other matter can lodge.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
xi.
xii.
xiii.
Contact surfaces at all connections shall be free of loose scale, dirt, burrs, oil and
other foreign materials that might prevent solid seating of the parts.
Welded joints not permissible.
The rolling and cutting tolerance for steel product conforming to IS: 266 shall be
those specified in the IS: 1852-1973 with latest revision.
all dimensions are subject to the following tolerances:
a) dimensions up to and including 50mm:+1mm: and
b) dimensions greater than 50mm: +2%
xiv.
xv.
The channel cross arm shall be properly brushed to make it free from rust.
xvi.
he raw materials and fabrication thereof in respect of cross arm shall be furnished
along with dimension.
The hole for fixing of insulator and pole clamp shall be provided as per requirement.
One copy of the drawing of cross arm for each size shall be furnished along with
the technical bid.
xvii.
xviii.
a.
For galvanized channel :
All ferrous parts including all sizes of nuts, bolts, plain and spring washers,
support channels, structures, shall; be hot dip galvanized conforming to
latest version of 1S:2629 or any other equivalent authoritative standard. The
zinc coating shall be smooth, continuous and uniform. It shall be free from
acid spot and shall not scale, blister or be removable by handling or packing.
There shall be no impurities in the zinc or additives to the galvanic bath
which could have a detrimental effect on the durability of the zinc coating.
Before picking, all welding, drilling, cutting, grinding and other finishing
operations must be completed and all grease, paints, varnish, oil, welding
slag and other foreign matter completely removed. All protuberances, which
would affect the life of galvanizing shall also be removed.
The weight of zinc deposited shall be in accordance with that stated in
Standard IS 2629 and shall not less than 0.61kg/m² with a minimum
thickness of 86 microns for items of thickness more than 5mm,
0.46kg/m² (64 microns) for items of thickness between 2mm and 5mm
and 0.33kg/m² (47 microns) for items less than 2mm thick.
REQUIRED TECHNICAL SPECIFICATION FOR GI CHANNEL CROSS ARM
[100x50x6x3200 ]
Sl
Description
Particular
No.
1
Type of cross arm
G.I Channel cross arm
2
Size
100 x 50x 6 x 3200 mm
3
Material
Mild Steel channel
4
Length
3200 mm
5
Breath
100 mm
6
Width
50 mm
7
Thickness
6 mm
8
Hole for fixing of 26 mm
insulator
9
Center to center 1525 mm
distance of hole
10
Hole for pole clamp 18 mm
11
Weight
29.5 kg (approx)
12
Galvanization
The cross arm shall be properly
brushed to make it free from rust and
hot dip galvanized confirming to IS:
2629.
13
Standard applicable IS: 266; IS: 1852-1973:
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Technical Specification
Sl
No.
1
2
3
4
5
6
7
Description
10
Type of cross arm
Size
Material
Length
Breath
Width
Thickness
Hole for foxing of
insulator
Center to center
distance for hole
Weight
11
Galvanization
8
9
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Particular
GI Channel cross arm
75 x 40x 40x6 x 2200 mm
Mild Steel channel( galvanized)
2200 mm
75 mm
40 mm
6 mm
20 mm
1070mm
16 kg (approx)
The cross arm shall be properly
brushed to make it free from rust
and hot dip galvanized confirming
to IS: 2629.
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Technical Specification
3.17 TECHNICAL SPECIFICATION FOR 33 KV & 11KV DISC
INSULATOR (B&S) 70 KN
1.0 Scope: This specification covers design, manufacture, testing at manufacturers‘ works,
supply and delivery of strain insulators use on 11 KV and 33 KV overhead power
line.
2.0 Standard: 2.1. Strain insulators Ball & Socket type suitable for 11 kV & 33 kV lines shall be
conforming to Indian standard Specification IS: 731:1971 and IS: 3188 with its
latest amendments and revisions and having mechanical failing load of 70 KN.
2.2. Insulators conforming to any other internationally accepted standard which
ensure equal or higher quality than the standard mentioned will be acceptable.
2.3. Where the material is offered according to the internationally accepted standard
a copy of the specification shall be attached with the tender.
3.0 General requirements: 3.1. The porcelain shall be sound, free from defects, thoroughly vitrified and
smoothly glazed. Unless and otherwise specified glaze shall be brown in colour.
The glaze shall cover all the porcelain parts of the insulator except those areas
which serve as support during firing or are left unglazed for purpose of
assembly.
3.2. The design of the insulator shall be such that stress due to expansion and
contraction in any parts in any parts of the insulator shall not lead to
deterioration. The porcelain shall not engage directly with hard matel.
3.3. Cement used in the construction of insulator shall not cause fracture by
expansion or loosening by contraction and proper care shall be taken to locate
the individuals‘ parts correctly during commencing. The cement shall not give
rise to chemical reaction with metal fittings and its thickness shall be uniform as
possible.
i) The insulator shall be multi petticoat type./The insulator shall be in one
piece.
4.0 Basic Parameter: Sl no Particular
1
Type of insulator
2
Applicable Standard
3
Material
4
5
6
7
8
Type
Colour
Size
Minimum failing load
Socket cap
9
Ball pin
10
11
Security clip
Creepage distance
12
Nominal System voltage
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Disc insulator, 70 KV (B&S
type)
IS: 731:1971 and IS: 3188, IS:
2544/1973
Porcelain [sound, free from
defects, thoroughly vitrified
and smoothly glazed]
Ball & Socket
Brown
255x145 mm
70 KN
Malleable cast iron hot dip
galvanized of size 16 mm dia
High tensile/ forged hot dip
galvanized
Phosphor bronze ‗W‘ type
580mm ( for 33 KV)& 400 mm
( for 11 KV)
33kV/11 KV
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Technical Specification
13
Highest system voltage (rms)
14
Wet one minute power frequency test(rms)
15
Dry one minute power frequency test (rms)
16
Power frequency puncture withstand (rms)
17
Impulse voltage withstand test(Peak)
18 Power frequency flush and voltage (dry)
Power frequency flush and voltage (wet)
19
Visible discharge test
20
36 KV/12 KV
75 KV/35 KV
75 KV /35 KV
180 KV /105 KV
170 KV / 75 KV
95 KV ( r.m.s)
80 KV ( r.m.s)
27 KV ( r.m.s)
5.0
Mechanical Load: 5.1. The minimum failing load of the insulator shall 70 KN and the load shall be
applied transverse.
6.0
Creepage Distance: 6.1. The minimum total creepage distance for insulator shall be suitable for heavily
polluted and humid atmospheric conditions and shall be 400mm (for 11KV) &
900mm (for 33 K)
in vertical position.
7.0
Marking: 7.1. Each insulator shall be legibly and indelibly marked to show the following:
i) Name and trade mark of the manufacturer
ii) Month and year of manufacture
iii) Minimum failing load in KN
iv) Country of manufacturer.
v) ISI certificate marking if any
The marking on porcelain shall be printed and shall be applied before firing.
8.0
Packing: 8.1.
All insulators shall be suitably packed and crated to standard packing
practice as required under Railway Regulation to withstand rough handling
during transit.
9.0
Tests: The insulator shall stand the entire following test as per IS: 731/1971
(incorporating latest amendments and revisions).
9.1. Type tests –
The following type tests shall be conducted on the insulators (which have already
passed the routine test):
i) Visible discharge test (power frequency voltage)
ii) Impulse voltage withstand test
iii) Impulse voltage flashover test
iv) Verification of dimension
v) Wet one minute power frequency test and wet flashover tests
vi) Visual examination
vii) Mechanical failing load test
viii) Porosity test
9.2. The tenderer shall furnish copies of test certificates of the type test carried on
identical manufacturer with guaranteed performance data for the insulators
which they offer for supply. The report of type tests (on the insulator which is
passed the routine tests) tested in the National Test House, Alipore and or such
similar Government recognized Test House/ Institutions shall be invariably
submitted along with the tender.
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Technical Specification
9.3. Sample/ Acceptance tests: The samples (after withstanding the routine test) shall also be subjected to
the following sample acceptance tests as per ISS.
ix) Verification of dimensions
x) Temperature cycle test
xi) Mechanical failing load test
xii) Power frequency puncture withstands test
xiii) Porosity test
9.4. The following routine and factory tests shall be conducted at the time of
manufacture as per ISS.
xiv) Visual examination
xv) Electrical test
10.0
1)
2)
3)
a.
b.
c.
d.
e.
4)
a.
b.
c.
d.
e.
f.
g.
h.
i.
5)
6)
Guaranteed technical particulars: (To be filled by the tenderer)
Name and address of manufacturer.
Trade mark of manufacturer to the legibly marked in the insulator.
Mechanical characteristic.
Total creepage distance in mm.
Overall height of insulator in mm
Overall diameter of insulator in mm.
Overall weight of insulator in Kg.
Minimum failing load in KN.
Electrical characteristic
Visibly discharge voltage. (power frequency voltage)
Dry one minute power frequency withstands voltage.
Wet one minute power frequency withstands voltage.
Power frequency puncture withstands voltage.
Impulse (1/50 micro second wave) withstands voltage.
Impulse flashover (1/50 micro second wave) voltage.
Impulse flashover (1/50 micro second wave) voltage negative.
Dry flash over voltage.
Wet flash over voltage.
Standard specification to which insulator will conform.
Other particulars, if any.
11.0
Inspection: All tests and inspections shall be carried out at the place of manufacturer unless
otherwise agreed by the purchaser and the manufacturer at the time of
purchase. The manufacturer shall afford the inspector representing the
purchaser all reasonable facilities, without charge to satisfy that the materials are
being purchased as per specifications. The purchaser reserves the right to have
tests carried out at his own cost by an independent agency, whenever there is
dispute regarding the quality of the material supplied.
12.0
Drawing and Sample: Drawing specifically showing all dimensions is to be submitted along with
technical bids.
Sample should be furnished alongwith the tender for verifications. Firms whose
samples have been approved earlier need not submit the same.
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Technical Specification
3.18 TECHNICAL SPECIFICATION FOR 33 KV COMPOSITE
POLYMERIC DISC INSULATORS 70 KN
1.0
SCOPE
This specification cover the design, manufactures, testing at manufacturer's
works, transport to site, insurance, storage, erection and commissioning of 33
kV composite polymeric disc insulator for 33 kV line.
2.0
STANDARD
Strain insulators Tongue and Clevis type/ ball and socket type, suitable for 33 KV lines
shall be conforming to IEC : 1109 with its latest amendments and revision and having
mechanical failing load of 70 K.N. Insulators conforming to any other internationally
accepted standards which ensure equal or higher quality than the standard mentioned
would also be acceptable. A high class quality, corrosion resistant, fiberglass reinforced
rod is the core of every insulator with ultimate mechanical strength at least twice the
maximum working load.
Where the material is offered according to the inter-national accepted standard a copy
of the specification shall be attached with the tender.
2.1
GENERAL REQUIREMENT:
The composite polymer insulator should be uni-body design and injection molded
directly to the rod and sealed to the end fittings with bead of silicon to give the insulator
high dielectric strength and protect it from all environmental conditions. The design of
the insulator shall be such that stress due to expansion and contraction in any part of
the insulator shall not lead to deterioration.
2.2
The insulator shall be in one piece.
2.3
CLIMATIC CONDITIONS.:
i. Maximum ambient temperature in shade
ii. Minimum daily average ambient air temperature
iii. Maximum yearly average ambient air temperature
iv. Maximum ambient temperature
v. Maximum relative humidity
vi. Average number of thunder storms days per annum
vii. Average number of rainy days per annum
viii. Average annual rainfall
ix. Number of months of tropical monsoon conditions
x. Maximum wind pressure
xi. Altitude not exceeding
2.4
BASIC INSULATION LEVEL
The test voltage (minimum requirement) of the insulator shall be as follows:
a)
b)
c)
d)
e)
f)
2.5
: 40°C
: 35°C
: 30°C
: 2°C
: 93%
: 45 days
: 150 days
: 2280 mm
: 5 months
: 150 Kg/sq.m
: 1000 M
Highest system voltage
Min. Creepage distance
Section length
Rated mechanical tensile load
Wet frequency 1 min. withstand voltage
Dry lighting impulse withstand voltage
: 36 KV(rms)
: 1050mm
: 680mm
: 70 KN
: 85KV
: 230KV
MARKING
Each insulator shall be legibly and indelibly marked to show the following:
a)
Name or trade mark of the manufacturer
b)
Month and year of manufacture
c)
Minimum failing load in KN
d)
Country of manufacture
e)
ISI certificate mark and name of the project under "TDF 2010-11"
The marking on insulator shall be printed and shall be applied before suitably.
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Technical Specification
3
TEST
3.1
Type test
The following type tests shall be conducted on a suitable number of individual insulator
unit, components, materials or complete strings:
Verification of dimensions
Thermal mechanical performance test
Power frequency voltage withstand and flashover test (i) dry (ii) wet
Impulse voltage withstand and flashover test (dry)
Visible discharge test (dry)
RIV test (dry)
Mechanical failing Load Test (for pin insulator only)
24 hrs. mechanical strength test (for strain I string insulator only)
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
4.0
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
m)
n)
o)
p)
Acceptance Tests
Visual examination
Verification of dimensions
Temperature cycle test
Galvanizing test
Mechanical performance test
Test on locking device for ball and socket coupling
Eccentricity test
Metallurgical test
Grain size
Inclusion rating
Chemical analysis
Microstructure
Mechanical failing load test (for Pin Insulator only)
Electro-mechanical strength test (for Strain insulator only)
Porosity test
Puncture test (for strain Insulator only)
4.1
Routine Tests
a. Visual Inspection
b. Mechanical routine test for Strain Insulator only)
c. Electrical routine test (for Strain Insulator only)
4.2
Tests During Manufacture
On all components as applicable
Chemical analysis of zinc used for galvanizing
Chemical analysis, mechanical, metallographic test and magnetic particle inspection for
malleable castings.
Chemical analysis hardness tests and magnetic particle inspection for forgings
Hydraulic Internal Pressure tests On disc insulator shells
a)
b)
c)
d)
4.3
4.4
4.5
4.6
4.7
Test Reports
Copies of type test reports shall be furnished in at least six (6)' copies along with one
original. One copy shall be returned duly certified by the Owner only after which the
commercial production of the concerned materials shall start.
Copies of acceptance test reports shall be furnished in at least six (6) copies. One copy
shall be returned duly certified by the Owner, only after which the material shall be
despatch.
Record of routine test reports shall be maintained by the Contractor at his works for
periodic inspection by the Owner's representative.
Test certificates of test during manufacture shall be maintained by the Contractor. These
shall be produced for verification as and 'When desired by the Owner.
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Technical Specification
5.0
5.1
INSPECTION
The Owner's representative or third party nominee shall at all times be entitled to have
access to the works and all places of manufacture, where insulator, and its component
parts shall be manufactured and the representatives shall have full facilities for
unrestricted inspection of the Contractor's and sub Contractor's works, raw materials,
manufacture of the material and for conducting necessary test as detailed herein.
5.2
The material for final inspection shall be offered by the Contractor only under packed
condition as detailed in the specification. The Owner shall select samples at random
from the packed lot for carrying out acceptance tests.
5.3
After placement of award, the Contractor shall submit fully dimensioned insulator
drawings containing all the details, in four (4) copies to Owner for approval. After getting
approval from Owner and successful completion of all the type tests, the Contractor shall
submit 20 more copies of the same drawing to the Owner for further distribution and field
use at Owner's end.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
3.19 TECHNICAL SPECIFICATION FOR 11 KV COMPOSITE
POLYMERIC INSULATORS
1.0
SCOPE
This section covers the specifications for design, manufacture, shop & laboratory testing
before despatch of 11 kv composite polymeric pin insulators .The Composite insulator
shall be pin insulator for straight line location and Long rod insulator for conductors in
tension application at angle/ cut point, the insulator shall be of boll and socket type or
tongue & Clevis type.
1.1 STANDARDS
Sl.
Indian
No.
Standard
1.
2.
IS:731
3.
4.
IS:2071
IS:2486
5.
6.
IS:13134
7.
8.
12.
13.
14.
15.
16.
IS:8263
IS:4759
IS:2629
IS:6745
IS:3203
IS:2633
17.
18.
19.
Definition, test method and acceptance
criteria for composite insulators for a. c.
overhead lines above.
Porcelain insulators for overhead power
lines with a nominal voltage greater than
1000V
Methods of High voltage testing
Specification for insulator fitting for
overhead power lines with a nominal
voltage greater than 1000V General
Requirements and tests Dimensional
Requirements locking devices.
Thermal mechanical performances test on
string insulator units.
Guide for the selection of insulators in
respect of polluted conditions.
Characteristics of string insulator units of
the long rod type.
Hydrophobicity classification
9.
10.
11.
Title
IS:4699
Radio interference characteristics of
overhead power lines and high-voltage
equipment
Methods of RI test of HV insulators
Standard for insulators- composite
distribution dead end type
Hot dip Zinc coatings on structural steel &
other allied products.
Recommendation of weight for hot, dip
galvanization for iron and steel
Determination of weight of Zinc coatings on
zinc coated iron and steel articles
Method of testing of local thickness of
electroplated coating
Testing of uniformity of coating of zinc
coated articles
Standard specification for glass fiber
standards
Standard test method for compositional
analysis of thermogravimetry
Specification for refined secondary Zinc
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
International
Standard
IEC:61109
IEC:60383
IEC:60060-1
IEC:60120
IEC:60372
IEC:60575
IEC:60815
IEC:60433
STRI GUIDE
1.92/1
CISPR:18-2
PART2
IEC:60437
ANSI c29.13-2000
ISO:1459
ISO:1461
ISO:1461(E)
ISO:1460
ISO:2178
ASTM D 578-05
ASTME 1131- 03
Assam Power Distribution Company Ltd
185
Technical Specification
1.2
SERVICE CONDITION
Maximum ambient temperature :* *480 C
Minimum ambient temperature
: - 50 C
Relative humidity
: 0 to 100%
The size of composite insulator, minimum creepage distance and mechanical strength
alongwith hardware fittings shall be as follows.
Minimum
Creepage
Wet
distance (mm)
Nomi
power Impuls
Pin
Type
Visible
nal
Higest
freque
e
ball
Normal
Hea
Sl
of
dischar
Min.
syste system
ncy
withsta
shan
&
vily
. compo
ge test
Failing
m
voltage
withst
nd
kdia
moder pollu
N
site
voltage
load
voltag
KV
and
voltage
mete
ately
ted
o. insulat
KV
KN
e KV
(rms)
voltag
KV
r
pollute (25m
or
(rms
(rms)
e KV
(rms
mm
d
m/
(rms
(20mm/
KV)
KV)
i
Long
11
12
9
35
75
240
320
45
16
rod
insula
33
36
27
75
170
720
900
45/70**
tor
ii
Post/
11
12
9
35
75
240
320
5
pin
insula
33
36
27
75
170
720
900
10
tor
Dimensional Tolerance of composite insulators
±(0.04d=1.5) mm when d < 300 mm
±(0.025d=6) mm when d < 300 mm
REQUIRED TECHNLCAL PARICULARS OF COMPOSIT POLYMERIC INSULATOR
FOR 11 KV , 5 KN PIN INSULATOR TYPE
Sl. no
Description
Unit
11KV , 5 KN , PIN
INSULATOR
1.
Type of Insulator
Composite polymeric
Insulators
2.
Standard according to which the
IES-61109 with up to date
Insulator manufacture and tested
amendments
3.
Name of material used in
Silicon/ Polyolefin material
manufacture
Of the insulator with class/grade
(a)
Material of core (FRP rod)
ECR glass boron content
i) E-glass or ECR- glass
free
ii) Boron content
(b)
Material of housing &Weather
36%
sheds
Silicon content by weight
(c)
( material of end fitting )
(d)
4.
5.
(a)
(b)
Sealing compound for end fittings
Color
Electrical characteristics
Normal system voltage
Highest system voltage
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Hot dip galvanized high
strength steel
Silicon based sealants
Grey/ Red
KV(rms )
KV(rms)
11 KV
12 KV
Assam Power Distribution Company Ltd
186
Technical Specification
(c)
Dry power Frequency withstand
voltage
(d)
Wet power frequency withstand
voltage
(e)
Dry flashover voltage
(f)
Wet flashover voltage
(g)
Dry lighting impulse withstand
voltage
a) Positive
b)Negative
(h)
(i)
(j)
6.
(a)
Dry lighting impulse flashover
voltage
c) positive
d) Negative
R/V at 1MHz when energized at
10KV/30KV(rms) under dry
condition
Creepage distance (mm)
Mechanical characteristics
Minimum failing load
KV(rms )
35 KV
KV (rms )
35 KV
KV(rms)
KV(rms)
KV(peak)
>35KV
>35KV
KV(peak)
75KV
75 KV
KV(peak)
95KV
95 KV
KV(peak)
Microvolt
As per IES specification
mm
320 mm
KN
5KN
REQUIRED TECHNLCAL PARICULARS OF COMPOSIT POLYMERIC INSULATOR
FOR 11 KV , 45 KN ( T & C ) TYPE
Sl. no
Description
Unit
11KV , 45 KN , T& C type
1.
Type of Insulator
Composite polymeric
Insulators
2.
Standard according to which the
IES-61109 with up to date
Insulator manufacture and tested
amendments
3.
Name of material used in
Silicon/ Polyolefin material
manufacture
Of the insulator with class/grade
(a)
Material of core (FRP rod)
ECR glass boron content
i) E-glass or ECR- glass
free
ii) Boron content
(b)
Material of housing &Weather
36%
sheds
Silicon content by weight
(c)
( material of end fitting )
(d)
4.
5.
(a)
(b)
(c)
Sealing compound for end fittings
Color
Electrical characteristics
Normal system voltage
Highest system voltage
Dry power Frequency withstand
voltage
Wet power frequency withstand
voltage
Dry flashover voltage
Wet flashover voltage
(d)
(e)
(f)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Hot dip galvanized high
strength steel
Silicon based sealants
Grey/ Red
KV(rms )
KV(rms)
KV(rms )
11 KV
12 KV
35 KV
KV (rms )
35 KV
KV(rms)
KV(rms)
>35KV
>35KV
Assam Power Distribution Company Ltd
187
Technical Specification
(g)
Dry lighting impulse withstand
voltage
a) Positive
b)Negative
(h)
(i)
(j)
6.
(a)
7.
Dry lighting impulse flashover
voltage
c) positive
d) Negative
R/V at 1MHz when energized at
10KV/30KV(rms) under dry
condition
Creepage distance (mm)
Mechanical characteristics
Minimum failing load
Dimension of insulator
KV(peak)
KV(peak)
75KV
75 KV
KV(peak)
KV(peak)
95KV
95 KV
Microvolt
As per IES specification
mm
320 mm
KN
45KN
Inter changeability
The composite insulators including the end fitting connection shall be of standard design
suitable for use with the hardware fittings of any make conforming to relevant IEC/IS
standards.
Corona and RI performance
All surfaces shall be clean, smooth without cuts, abrasions or projections. No parts shall
be subjected to excessive localized pressure. The insulator and metal parts shall be so
designed and manufactured that it shall avoid local corona formation and not generate any
radio interference beyond specified limit under the operating conditions.
Core
It shall be a glass – fiber reinforce epoxy resin rod of high strength (FRP rod). Glass
fibers and resin shall be optimized in the FRP rod. Glass fibers shall be Boron free electrically
corrosion resistant(ECR) glass fiber or boron free E- class and shall exhibit both high electrical
integrity and high resistance to acid corrosion . the matrix of the FRP rod shall be Hydrolysis
resistant. The FRP rod shall be manufactured through pultrusion process . the FRP rod shall
be void free.
Housing (Sheath)
The FRP rod shall be covered by a seamless sheath of a silicon elastometric
compound or silicon alloy compound of a thickness of 3 mm minimum.
It should protect the FRP rod against environment influences, external pollution and humidity.
It shall be excluded or directly moulded on the core and shall have chemical bonding with the
FRP rod. The strength of the bond shall be greater than the tearing strength of the polymer.
Sheath material in the bulk as in the sealing/ bonding area shall be free from voids.
Weather sheds
The composite polymer weather sheds made of silicon elastomeric compound of silicon
alloy shall be firmly bounded to the sheath, vulcanized to the sheath or moulded as part of the
sheath and shall be free from imperfections. The weather sheds should have silicon content of
minimum 30% by weight. The strength of the weather sheds to sheath interface shall be
greater than the tearing strength of the polymer. The interface, if any, between sheds and
sheath (housing) shall be free from voids.
End Fittings
End fittings transmit then mechanical load to the core. They shall be made of spheroid
graphite cast iron, malleable cast iron or forged steel or aluminium alloy. They shall be
connected to the rod by means of a controlled compression technique. The gap between fitting
and sheath shall be sealed by a flexible silicon elastomeric compound or silicon alloy
compound sealant. System of attachment of end fitting to the rod shall provide superior sealing
performance between housing, i.e. seamless sheath and metal connection. The sealing must
be moisture proof.
The dimensions of end fittings of Insulators shall be in accordance with the standard
dimensions stated in IS:2486/IEC:60120
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
188
Technical Specification
Equipment Marking
5.1 Each insulator unit shall be legibly and marked with the following details as per IEC61109
(a) Month & Year of manufacture
(b) Min. Failing load/ guaranteed mechanical strength in kilo Newton followed by the
word KN to facilitate easy identification.
(c) Manufacture‘s name / trade mark.
5.2 One 10mm thick ring or 20mm thick spot of suitable quality of paint shall be marked on
the end fitting of each composite long rod of [particular strength in case of 33 KV insulators
for identification in case both type of insulators are procured by the utility. The paint shall be
not have deteriorating effect on the insulator performance, following codes shall be used as
identification mark:
For 45 KN Long unit
: Blue
For 70 KN Long unit
: Red
6.0 Bid Drawings
6.1 The full description and illustration of the materials offered.
6.2 The bidder furnish alongwith the bid the outline drawing ( 3 copies ) of each insulator
unit including a cross sectional view of the long rod insulator unit. The drawing shall include
but not be limited to the following information.
(a) Long rod diameter with manufacturing tolerance.
(b) Minimum creepage distance with positive tolerance.
(c) Protected creepage distance.
(d) Eccentricity of the long rod unit
(i)
Axial run out
(ii)
Radial run out
(e) Unit mechanical and electrical characteristics
(f) Size and weight of ball and socket/ tongue & cleaves
(g) Weight of composite long rod units
(h) Materials
(i)
Identification Mark
(ii)
Manufacturer‘s catalogue number
7.0
Type tests
Sl.
No.
1.
Description of type test
Test procedure / standard
As per IEC 61109 (Clause 6.1)
2.
3.
4.
Dry lightning impulse withstand
voltage test
Wet power frequency test
Mechanical load- time test
Radio Interference test
5.
Recovery of Hydrophobicity test
6.
Chemical composition test
silicon content
Brittle fracture resistance test
7.
8.0
8.1
for
As per IEC 61109 (Clause 6.2)
As per IEC 61109 (Clause 6.4)
As per IEC 61109 (Clause 6.5)
revised
Annexure-B This test may be
repeated every 3 yrs by the
manufacturer
Annexure-B or any other test method
acceptable to the owner
Annexure-B
Acceptance (Sample) Tests
For Composite Insulators
A
Verification of dimensions
B
Verification of the locking system ( if
possible)
C
Galvanizing Test
D
Verification of the specified mechanical
load
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Clause 7.2 IEC:61109
Clause 7.3 IEC:61109
IS 2633 / IS 6745
Clause 7.4 IEC:61109
Assam Power Distribution Company Ltd
189
Technical Specification
8.2
8.3
Routine Tests
Sl.
Description
No.
1.
Identification of marking
2.
Visual Inspection
3.
Mechanical routine test
Standard
As per IEC:61109 Clause 8.1
As per IEC:61109 Clause 8.2
As per IEC:61109 Clause 8.3
Tests During Manufacture
Following tests shall also be carried our
A
Chemical analysis of zinc used for galvanizing
B
Chemical analysis, mechanical, metallographic test and magnetic
particle inspection for malleable castings
C
Chemical analysis, hardness and magnetic particle inspection for
forigngs
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
190
Technical Specification
3.20 TECHNICAL SPECIFICATION FOR HARDWARE FITTING FOR
DISC INSULATOR, 70 KN( B& S)
1.0
Scope: This specification covers design, drawings, manufacture, testing at
manufacturers‘ works, supply and delivery of hardware fittings for strain insulator
of ball & socket type .
The fitting shall consist of the following component :
a) Cross arm strap conforming to IS: 2486 ( Pt-II)-1989.
b) Forged steel ball eye for attaching the socket end of the strain insulator to
the cross arm strap. Forging shall be made of steel as per IS : 2004-1978.
c) Aluminium alloy thimble socket made out of permanent mould cast , high
strength aluminium alloy for attaching to the strain insulator on one end and
for accommodating the loop of the helically formed dead-end fittings at the
other end in its smooth internal contour. The thimble socket shall be attached
to the strain insulator with the help of locking pin as per the dimension given
in IS: 2486(PT-II)-1989
d) Helically formed dead-end grip having a pre-fabricated loop to fit ito the
grooved contour to the thimble on one end and for application over the
conductor at the other end. The formed fitting shall conform to the
requirement of IS:12048-1987.
2.0
Tests:
The helically formed fittings for strain insulators shall be subjected to tests as per
IS:12048-1987. The other hardware fittings shall be tested as per IS:2486 (Part-I)
3.0
Packing:
For packing of strain clamps and related hardware, double gunny bags or wooden
cases shall be used. The fittings shall be properly protected against damage.
The gross weight of the packing shall not normally exceed 50 Kg. Helically formed
fittings shall be packed in card board / wooden boxes. Fittings for different sizes of
conductors shall be packed in different boxes and shall be complete with their
minor accessories fitted in place and colour codes on tags / fittings shall be
marked to identify suitability for different sizes of conductors as per IS:12048-1987
4.0
Inspection:
All tests and inspections shall be made at the place of manufactur unless
otherwise especially agreed upon by the manufacturer and purchaser at the time
of purchase. The manufacturer shall afford the inspector representing the
purchaser all reasonable facilities, without charge, to satisfy him that the material
is being furnished in accordance with this specification.
The purchaser has the right to have the tests carried out at his own cost by an
independent agency whenever there is dispute regarding the quality of supply.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
191
Technical Specification
3.21 TECHNICAL SPECIFICATION FOR POLYMERIC 33 KV AND 11
KV PIN INSULATOR
1.0
Scope
This specification covers design, manufacture, testing at manufacturer‘s works,
transport to site, storage, insurance, erection and commissioning of polymeric
33 KV pin insulator for 33 kV lines.
2.0
Standard
Polymeric compact insulator with suitable groove in upper pin and long threads
in lower part of the pin with nuts, suitable for 33 KV lines shall be conforming to IEC :
1109 with its latest amendments and revision and having minimum mechanical failing
load of 10 K.N. Insulators conforming to any other internationally accepted standards
which ensure equal or higher quality than the standard mentioned would also be
acceptable. A high class quality, corrosion resistant, fiberglass reinforced rod is the core
of every insulator with ultimate mechanical strength at least twice the maximum working
load.
3.0
General Requirements
4.0
The composite polymer insulator should be uni-body design and injection molded
directly to the rod and sealed to the end fittings with bead of silicon to give the insulator
high dielectric strength and protect it from all environmental conditions. The design of the
insulator shall be such that stress due to expansion and contraction in any part of the
insulator shall not lead to deterioration.
5.0
The insulator shall be in one piece.
The dimensions of the pins insulator shall be as follows:
33 KV
11KV
a) Composite insulator length
310 mm
210 MM
b) Failing minimum load
10 KN
5 KN
c) Creepage distance (min) mm
925 mm
580 mm
d) Dry power frequency 1 min withstand voltage
70 kV (RMS) 70
kV(RMS)
e) Wet power frequency 1 min withstand voltage
70 kV (RMS) 70
KV(RMS)
f) Dry lightning impulse withstand voltage
170 Kvp
145 Kvp
6.0
Tests
Pin shall comply with the following tests.
1.1
Type test:
a) Visual examination test
b) Verification of dimensions
c) Checking of threads
d) Galvanizing test
e) Mechanical strength tests
1.2
Routine test:
a) Visual examination test
1.3
Acceptance test:
Checking of threads on heads
a) Galvanizing test
b) Mechanical test
7.0
Inspection
All tests and inspections or shall be carried out at the place of manufacturers unless
otherwise agreed by the purchaser and the manufacturers at the time of purchase. A
manufacturer shall afford the inspector or third party nominee representing the
purchaser all reasonable facilities, without charge to satisfy that the materials are being
purchased as per specification. The purchaser reserved the right to have the test
carried out at his co.st by an independent agency, whenever there is dispute regarding
the quality of the materials supplied.
8.0
Marking
The pins shall be marked with name of manufacturer, year and name of project.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
192
Technical Specification
3.22 TECHNICAL SPECIFICATION FOR 33 kV AND 11kV PIN
INSULATOR
1.0
SCOPE
This specification covers the design, manufacture, testing at manufacturer's
works, transport to site, insurance, storage, erection and commissioning of
insulators required for 33 kV and 11kV lines.
2.0
STANDARD
2.1
2.2
2.3
2.4
2.5
3.0
The pin insulators shall comply with the Indian Standard specification IS : 731/1971 as
amended from time to time having mechanical failing load of 10 K.N for 33 kV insulator
and 5KN for 11kV insulator.
 Insulators conforming to any other internationally accreted standards which
ensure equal or higher quality than the standard mentioned would also be
acceptable.
 Where the material is offered according to the inter-national standard a copy of
the specification shall be attached with the tender.
General requirement: The porcelain should be sound, free from defects, thoroughly
vitrified and smoothly glazed.
Unless otherwise specified, the glaze shall be brown colour. The glaze shall cover all
the porcelain parts of the insulators except those areas which serve as support during
firing or are left unglazed for purpose of assembly.
The design of the insulator shall be such that stress due to expansion and contraction in
any part of the insulator shall not lead to deterioration. The porcelain shall not engage
directly with hard metal.
Cement used in the construction of insulator shall not cause fracture by expansion or
loosening by contraction and proper care shall be taken to locate the individual parts
correctly during cementing. The cement shall not give rise to chemical reaction with
metal fitting and its thickness shall be as uniform as possible.
The insulator shall be multi-petty-coat type.
BASIC PARAMETER:
Sl No
Particu
lars
1
Type of insulator
2
Applicable
Standard
3
Material
4
5
6
7
8
9
10
11
Dimension
Minimum failing
load
Creepage
distance
Nominal System
voltage
Highest system
voltage (rms)
Wet one minute
power frequency
test(rms)
Dry one minute
power frequency
test (rms)
Power frequency
flush over voltage
(Dry)
33 KV Pin Insulator
11kV Pin Insulator
IS : 731/1971
Porcelain sound, free from defects, thoroughly
vitrified and smoothly glazed.
210x280x145 mm
155x160 mm
10 KN
5KN
580 mm
320mm
33kV
11kV
36 KV
12kV
75 KV
95 KV
95 KV
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
193
Technical Specification
12
13
14
4.0
Power frequency
flush over voltage
(Wet)
Power frequency
puncture
withstand (rms)
Impulse withstand
voltage test(Peak)
80 KV
180 KV
170 KV
MECHANICAL LOADS
The minimum failing load of the insulators shall be 10 KN for 33 kV
for 11kV and the load shall be applied in transverse direction.
and 5KN
5.0
CREEPAGE DISTANCE
The minimum total creepage distance for 33kV insulators shall be 580 mm and
320mm for 11 kV insulators.
6.0
MARKING
Each insulator shall be legibly and indelibly marked to show the following:
a.
Name or trade mark of the manufacturer
b.
Month and year of manufacture
c.
Minimum failing load in KN
d.
Country of manufacture
e.
ISI certificate mark, if any
f.
Name of the Project
The marking on porcelain shall be printed and shall be applied before firing.
7.0
Type Tests
The following type tests shall be conducted on 'a suitable number of individual
insulator unit, components, materials or complete strings:
a) Verification of dimensions
b) Thermal mechanical performance test
c) Power frequency voltage withstand and flashover test (i) dry (ii) wet
d) Impulse voltage withstand and flashover test (dry)
e) Visible discharge test (dry)
f) RIV test (dry)
g) Mechanical failing Load Test (for pin insulator only)
h) 24 hrs. mechanical strength test (for strain / string insulator only)
8.0
Acceptance Test
a) Visual examination
b) Verification of dimension
c) Temperature cycle test
d) Galvanizing test
e) Mechanical performance test
f) Test on locking device for ball and socket coupling
g) Eccentricity test
h) Metallurgical test
i) Grain test
j) Inclusion rating For metal fittings only (in black condition)
k) Chemical analysis
l) Microstructure.
m) Mechanical failing load test (for Pin Insulator only)
n) Electro-mechanical strength test (for strain insulator only)
o) Porosity test
p) Puncture test(for Strain Insulator only)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
194
Technical Specification
9.0
ROUTINE TEST
a)
b)
c)
Visual Inspection
Mechanical routine test (for Strain Insulator only)
Electrical routine test (for Strain Insulator only)
10.0
Tests During Manufacture
On all components as applicable
a) Chemical analysis of zinc used for galvanizing
b) Chemical analysis, mechanical, metallographic test and magnetic particle inspection
for malleable castings.
c) Chemical analysis hardness tests and magnetic particle inspection for forgings
d) Hydraulic Internal Pressure tests On disc insulator shells
11.0
Test Reports
Copies of type test reports shall be furnished in at least three (3) copies along with one
original. One copy shall be returned duly certified by the Owner only after which the
commercial production of the concerned materials shall start.
11.1
Copies of acceptance test reports shall be furnished in at least six (6) copies.
One copy shall be returned duly certified by the Owner, only after which the
material shall be despatch.
11.2
11.3
Record of routine test reports shall be maintained by the Contractor at his works for
periodic inspection by the Owner's representative.
Test certificates of test during manufacture shall be maintained by the Contractor.
These shall be produced for verification as and when desired by the Owner.
12.0
Inspection
a) The Owner's representative or third party nominee shall at all times be entitled to
have access to the works and all places of manufacture, where. insulator, and its
component parts shall be manufactured and the representatives shall have full
facilities for unrestricted inspection of the Contractor's and ;1ub-Contractor's works,
raw materials, manufacture of th::; material and for conducting necessary test as
detailed herein.
b) The material for final inspection shall be offered by the Contractor only under
packed condition as detailed in the specification. The Owner shall select samples at
random from the packed lot for carrying out acceptance tests. Insulators shall
normally be offered for inspection in lots not exceeding 5000 nos. the lot should be
homogeneous and should contain insulators manufactured in the span of not more
than 3-4 consecutive weeks.
c) The bidder shall keep the Owner informed in advance of the time of starting and the
progress of manufacture of material in their various stages so that arrangements
could be made for inspection.
d) No material shall be dispatched from its point of manufacture before it has been
satisfactorily inspected and tested unless the inspection is waived off by the Owner
in writing. In the latter case also the material shall be dispatched only after
satisfactory testing for all tests specified herein have been completed.
e) The acceptance of any quantity of material shall be no way relieve the Contractor of
his responsibility for meeting all the requirements of the specification and shall not
prevent subsequent rejection, if such material are later found to be defective.
13.0
BID DRAWING
The Bidder shall furnish full description and illustration of the material offered.
The Bidder shall furnish along with the bid the outline drawing (6 copies) of each
insulator unit including a cross sectional view of the insulator shell. The drawing shall
include but not limited to the following information:
a. Dimensions with manufacturing tolerances
b. Minimum creepage distance with positive tolerance
c. Protected creepage distance
d. Eccentricity of the disc
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
195
Technical Specification
i. Axial run out
ii. Radial run out
e. Unit mechanical and electrical characteristics
f. Size and weight of Pin Ball Shank / ball and socket parts
g. Weight of unit insulator disc
h. Materials
i. Identification mark
j. Manufacturer's catalogue number
After placement of award, the Contractor shall submit fully dimensioned insulator
drawings containing all the details, in four (4) 'copies to Owner for approval. After
getting approval from Owner and successful completion of all the type tests, the
Contractor shall submit 20 more copies of the same drawing to the Owner for further
distribution and field use at Owner's end.
14.0
Guaranteed Technical Particulars
The guaranteed technical particulars in respect of the Pin Insulators offered shall
be submitted along with the tender.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
196
Technical Specification
3.23 TECHNICAL SPECIFICATION FOR G.I. PIN OF 33kV and 11kV
PIN INSULATOR
1.0
1.1.
Scope
This specification covers design, manufacture, testing at manufacturer‘s
works, transport to site, storage, insurance, erection and commissioning
of galvanized forged steel pins for use in 11 KV and 33 kV lines.
2.0 Standard
2.1. The galvanized Iron forged steel pins shall be of type L-230 N conforming to IS
2486 (PT-I/1971) and IS: 2486 (PT-11/1963) having stalk length of 300 mm and
shank length of 150 mm with minimum failing load of 10 kN. Details of the pin
are shown in the drawing.
2.2. The pins conforming to any other internationally accepted standards which
ensure equal or higher quality than the standard mentioned would also be
acceptable.
3.0
General Requirements
3.1.
The pins shall be single piece obtained by process of forging. They shall not be
made by joining, welding, shrink fitting or any other process for more than one
piece of materials. They shall be of good finish, free from flaws and other
defects. The finish of the collar and the shank is avoided.
All ferrous pins, nuts spring washers shall be galvanized and small fittings like
spring washers, nuts etc. may be electroplated with zinc. The threads of nuts
and tapped holes etc. shall be rounded. The galvanizing should be as per ISS:
2633/1964.
3.2.
3.3.
The dimensions of the 33kV Pins shall be as follows:
Particulars
Minimum failing load
Stalk length
Shank length
Thickness of collar
33kV Pin
10KN
230mm
150 mm
6 mm
11kV Pin
5KN
165mm
150mm
5mm
Diameter of collar
Diameter of shank
Threaded length of shank
Diameter of stalk head
Threaded length of stalk
50 mm
24 mm
100 mm
27.78 mm
47 mm
40mm
20mm
100mm
18.29
40mm
3.4.
The pins shall have minimum failing load of 10 kN and 5KN for 33 kV.and 11kV
Pin respectively.
3.5.
Tests
Pin shall comply with the following tests.
Type test:
3.6.
e) Visual examination test
f) Verification of dimensions
g) Checking of threads
h) Galvanizing test
e) Mechanical strength tests
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Technical Specification
3.7. Routine test:
a) Visual examination test
3.8.
Acceptance test:
Checking of threads on heads
c) Galvanizing test
d) Mechanical test
4.0 Inspection
4.1. All tests and inspections or shall be carried out at the place of manufacturers
unless otherwise agreed by the purchaser and the manufacturers at the time of
purchase. A manufacturer shall afford the inspector or third party nominee
representing the purchaser all reasonable facilities, without charge to satisfy that
the materials are being purchased as per specification. The purchaser reserved
the right to have the test carried out at his cost by an independent agency,
whenever there is dispute regarding the quality of the materials supplied.
5.0Marking
5.1. The pins shall be marked with name of manufacturer, year and name of project.
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Technical Specification
3.24 TECHNICAL SPECIFICATION FOR AAA “WOLF” & “RACCOON”
CONDUCTOR
1.0
2.0
3.0
4.0
Scope
This specification covers design, manufacture, testing at works, transport,
insurance, storage, erection and commissioning of All Aluminum Alloy
Stranded Conductors at site in 33 KV.
Conductor Size
13.0 19/3.40 mm (175 mm² Alloy Area) – wolf
14.0 7/3.81 mm ( 80 mm² Alloy Area ) - Raccoon
Applicable Standards
Unless otherwise stipulated in this specification, the conductor shall comply with
IS:398 (Part-IV)- 1994 or the latest version thereof.
Properties of Wires
The properties of Aluminium alloy wires to be used in the construction of the
stranded conductors shall be as in the following Table-1
Table-1
Cross
Maximum
area of
Diameter
breaking
nominal Mass
Resistance at 20° C
load after
Dia
stranding
wire
Nominal
Min
Max
Max
Stamdard
2
Mm
mm
mm
mm
Kg/Km
KN
Ohm/Km Ohm/Km
3.40
3.37
3.43
9.079
24.51
2.80
3.67
3.96
3.81
3.77
3.85
11.401 30.78
3.34
2.938
2.851
5.0
6.0
Properties of Conductors
The properties of stranded all aluminium alloy conductors of various sizes shall
be as in the following table-II
All Aluminium Alloy Conductors ( AAAC)
Nomin
al
Alloy
Area
Stranding
& Wire
dia
Sectional
area
Approx.
overall
dia
Approx.
Mass
1
mm2
173
80
2
Mm
19/3.40
7/3.81
3
mm2
172.52
79.81
4
mm
17.00
11.43
5
Kg/Km
474.02
218.26
Calculate
d
resistanc
e at 20°
C (Max)
6
Ohm/Km
0.1969
0.425
Approx
calculate
d
breaking
load
7
KN
50.54
23.41
Free From Defects
The wire shall be smooth and free from all imperfection such as spills, splits etc.
7.0
Joints in Wires
Conductors containing three/seven wires. There shall be no joint in any wire of a
stranded conductor containing three/seven wires except those made in the base
rod or wire before final drawing.
8.0
Stranding
8.1
The wires used in the construction of a stranded conductor shall before stranding
satisfy all the relevant requirements of this standard.
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Technical Specification
8.2
The lay shall be within the limits given in Table-III
Lay Ratios for Aluminium Alloy Stranded Conductors
No. of wires in
conductors
7
19
Lay ration
Min.
10
10
Max
14
16
8.3
The outer layer shall be right handed. The wires in each layer shall be evenly
and closely stranded.
9.0
Climatic Conditions
The conductor shall be designed to suit for the climatic conditions specified in
these bidding documents.
10.0 Tests
The samples of individual wires for the test shall normally be taken before
stranding. The manufacturer shall carry out test on samples taken out at least
from 10% of aluminium wire spools. However, when desired by the purchaser,
the test sample may be taken form the stranded wires. However the minimum
breaking load test shall be done on a sample taken from stranded wires and the
minimum breaking load shall not be less than the value indicated in Table-I.
The wires for alloy conductors shall comply with the following tests as per IS:
398(Part-IV)-1994
i) Breaking loads test.
ii) Elongation test
iii) Resistance test
11.0
Packing and Marking
The conductors shall be owned in reels or drums conforming to the latest version
of IS: 1778-1980 ― Specification for reels and drums for bare wire and name of
the project TDF shall be indicated clearly on the drums.
10.1 Packing
10.1.1
The gross mass of packing of various conductors shall not exceed by
more than 10% of the values given in the following table:
Conductor size
Gross Mass
2
175 mm alloy area ( 19/3.40mm)
2500
80 mm² Alloy Area (7/3.81 mm)
1600 KG
10.1.2 The normal length of various conductors shall be as given in the following table:
Conductor size
175 mm2 alloy area ( 19/3.40mm)
80 mm² Alloy Area (7/3.81 mm)
Normal Length
1.1 Km
1.3 KM
10.1.3 Longer lengths shall be acceptable.
10.1.4 Short length , not less than 50% of the normal length shall be acceptable to the
maximum extent of 10% of the quantity ordered 10.2 marking.
The following information be marked on each package.
14.1. Manufacturer‘s name.
14.2. Trade Mark, if any.
14.3. Drum or identification number.
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Technical Specification
14.4. Size of conductor
14.5. Number & lengths of conductor
14.6. Gross Mass of the package
14.7. Net mass of the conductor
14.8. ISI certification mark.
14.9. Name of the Project TDF
11
INSPECTION
All tests and inspection shall be made at the place of manufacture. The
manufacturer shall afford the inspection representing the purchaser or third party
nominee all reasonable facilities without charge to satisfy him that the material is
being furnished in accordance with this specification.
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Technical Specification
3.25 TECHNICAL SPECIFICATION FOR HARDWARE FITTINGS
INCLUDING TENSION CLAMP ASSEMBLY (Aluminium Alloy)
FOR “RACCOON” AND “WOLF” CONDUCTOR
1.0
2.0
3.0
4.0
Scope: This specification covers design, drawings, manufacture, testing at
manufacturers‘ works, supply and delivery of suspension clamp for use with
Raccoon (7/3.81mm-80 sqmm)/Wolf (19/3.4mm-175 sqmm )conductors within
the state of Assam.
Standard: The material and process adopted in the manufacture shall conform to the
provision of the following standards amended up-to-date IS: 2486 specification
for Insulator fitting for overhead power lines.
General: The tension clamps offered shall be made of die cast high strength aluminium
alloy and shall be suitable for use with ―Raccoon and Wolf‖ conductors together
with one set of preformed armour rods. Suitable sheet metal liner shall be
provided.
The clamp shall move easy oscillation around horizontal axis.
The bidder is to quote separately for suspension clamp:
i)
Envelope type
ii)
Bottom free centre type design.
The single tension clamp shall consist of the following components: Description
Quantity
Material
1.
Ball hook without provision for
1 no.
Forged Steel
Arching horn
2.
Socket type without provision for 1set.
MCI
Arching horn
3.
Tension clamp for AAAC
1 no
Alumium alloy
Raccoon /Wolf conductors
The clamp shall be of high corrosion resistant, light in weight, have low effective
power loss and small moment of inertia enabling it to follows freely the
movements of the conductor
The tension clamp shall also be provided with suitable socket or clevis eye for
connecting it to the insulator string.
The seat and clamping surface should be smooth, without any projections or
sharp bends and should be formed to support the conductor on long, easy
curves at the comparatively sharp bends. Minimum failing load = 70 KN.
The slip strength of tension clamp shall not exceed 15% of the breaking load of
the conductor.
Tests: The hardware fittings shall be subjected to all the tests in accordance with
relevant Indian Standard Specifications. The purchaser shall have the right to
carryout acceptance tests, in the presence of representatives of the purchaser.
The bidder shall submit type test certificate along with the tenders.
The following tests shall be carried out.
i)
Type Test: (a) Slip Strength test for clamp.
(b) Mechanical test for clamp & fittings
(c)Heating cycle test.
(d) Verification of dimensions.
(e) Galvanizing / Electroplating test.
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Technical Specification
(f) Visual examination test
ii)
Acceptance Test:
a) Dimensional test.
b) Galvanizing test.
c) Mechanical test for clamp & fittings
d) Electrical Resistance Test.
iii)
Routine Test:
a) Visual examination test.
b) Routine mechanical test.
Guaranteed Technical Particulars (GTP) and drawing specifically showing
all dimensions are to be submitted along with technical bids
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Technical Specification
3.26 TECHNICAL SPECIFICATION FOR P.G CLAMP FOR AAA RACOON
/WOLF CONDUCTOR
1.0
2.0
Style
No.
Scope:
The scope covers design, manufacturing, testing at work, transport at site,
insurance, storage, erection and commissioning of P.G. Clamp suitable for
Conductor size Wolf/Raccoon/Weasel/3 Bolt Type strictly conforming to IS : 2121
and Galvanising conforming to IS : 2633 as per the following:
Standards:
 P.G. Clamps suitable for conductor size, wolf/raccoon/weasel 3 bolt types strictly
conforming to IS : 2121 and galvanizing conforming to IS: 2633 as per the following:
 P.G. clamp body to be made from aluminium alloy
 Clamps nuts and bolt and washer should be made of hot deep galvanized steel
 Spring washer be made of electro-galvanize special steel.
Conducto
r
Maximum
conductor
diameter in
mm
A
mm
B
mm
C
mm
D
mm
E
mm
Dimensions
No of
Bolts
Appro
x.
Weigh
t Kg.
A-83
Wolf
20.78
140
76
42
5/8
1
3
0.51
A-81
Racoon
14.45
95
57
30
1/2
2
2
0.18
3.0
Inspection may be carried out by the purchaser or third party nominee at any
stage of manufacture. The supplier shall grant free access to the purchaser's
representative or third party nominee at a reasonable time when the work is in
progress. Inspection and acceptance of any equipment under this specification
by the purchaser shall not relieve the supplier of his obligation of furnishing
equipment in accordance with the specification and shall not prevent
subsequent rejection if the equipment is found defective.
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Technical Specification
3.27 TECHNICAL SPECIFICATION OF XPLE CABLE FOR 11kV
SYSTEM
1.0
SCOPE:
The specification covers the design, testing, supply and delivery in proper
packed condition of different grade of 1 or 3 core. Aluminium Conductor,
Cross-linked polyethylene (XLPE) insulated, PVC sheathed, armoured,
screened Power Cables.
2.0
1.1
1.2
3.0
LOCATION:
The cables may be laid buried directly in ground at a depth of one metre in
average, any where in Assam and terminate for outdoor connection to a power
transformer or to overhead lines and also indoor connection for indoor
switchgear.
The cables may also be laid within covered cable trenches, in cable racks or
open-air ladder trays etc. for certain portion of lengths.
SYSTEM DETAILS:
3.1 Voltage grade (KV) of cable required
3.1 Service Voltage
…
3.2
Highest Voltage
3.3
Earthing System
3.4
B.I.L. for Cables
3.5
Fault Level (Maxim.)
…
Reference source not found.
3.6
Frequency
…
…
…
6.35/11
11 KV
12 KV
Solidly Earthed
75 KV for 11 KV
See
Clause
Error!
50 C/S.
4.1
STARDARDS:
4.2
The cable shall conform to the following standards to the extent of
LAEDCL requirement is fulfilled.
1) IS : 7098 (Part – II) (Latest) :Specification for cross-linked
polyethylene Insulated PVC Sheathed
Cables for working Voltage from 3.3
KV up to and including 33 KV.
2)
IS:8130 – 1984
:Specification for Conductors
for
insulated electric cables and flexible
cords.
3)
IS:5830 – 1984
:PVC insulation & sheath of electric
cables.
4)
IS:3975 – 1979
: Armour for cables (for 3 Crore).
5)
IS:10810 – 1984
: Methods for test for cables.
6)
IS:10418 – 1982
: Cable Drum for Electric Cables.
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Technical Specification
3.3
The cable, joints, outdoor and indoor termination and their accessories and
fittings may conform to other Indian and/or equivalent standards or important
publications to improve upon their performance, but shall not fall short of the
requirement of this specification. The tenderer shall clearly indicate such
standards in their offers.
4.0
ELECTRICAL CHARACTERISTICS & PERFORMANCE:
4.1
Description of Cable:
a) 6.35/11 KV Grade 3-Crore : Same as above but insulation shielding with
black semi-conducting tape not necessary. Inner sheath to be wrapped
not extruded and strip armoured. The design shall fully conform to
IS:7098 (Part – II).
b) SPECIFIC TECHNICAL REQUIREMENTS
Technical parameters of the cable shall be as follows:
Sl
No
1
2
3
4
5
Particulars
Unit
11 KV
Rated voltage
Type of insulation
Single Core
Armoured /Unarmoured
Material of Conductor
KV
-
6
7
8
9
10
System
Highest System Voltage
Material
Voltage Grade
Conductor Size
KV
-
11
Nominal dimention
of Al. round wire
12
Nominal thickness
of XLE insulationr sheath
Approx overall
cable diameter
11
XLPE
Single , three
Armoured
Material to IS: 8130, H4 Grade Aluminium
Conductor, Stranded compacted Circular
11 KV Earthed
12
Stranded Aluminium
6.35/11 KV
1x185,3x120
1x300
2.0mm[for 1x300sqmm ],
2.0mm [for 1x185sqmm
& 2.5mm[3x120 sqmm],
3.6 mm
13
14
a
Current rating
In ground at 300C
b
In air at 400C
15
Maxm.
Conductor Temp
Sq.
mm
61.50mm [for 3x120sqmm],
35.50mm [for 1x185sqmm]
40.00 mm [ for 1x300 sqmm],
219A(3x120sqmm),
296A(1x185sqmm)
381 A(1x300 sqmm)
288A(1x120sqmm),
378A(1x185sqmm)
512 A(1x300 sqmm
90 oC at maxm. Continuous current
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Technical Specification
16
Short Ckt.Current for 1
second duration
17
19
Maxm.Permissible
emergency overload
temp. at 25% overload
to 100 hrs. per year or
500 hrs. in life of cable
Maxm. Permissible
short circuit
temperature
Conductor Screening
20
21
Insulation Screening
Conductor Screening
22
Insulation
a
Insulation Screening
18
b
23
Inner Sheathing
24
Armouring
25
Overall Sheathing
26
Approx. length of cable
in a Drum
End Sealing
27
a
Max. ‗Tan-delta‘ at
room temp. At nominal
phase to neutral
11.3KA-for120 sqmm,
17.5 KA-for 185 sqmm,
28.3 KA – for 300 sqmm.
130 oC for one hour
250 oC for one hour
Extruded, cross linked, semi-conducting
compound of.5 mm for 11KV
:
Extruded, cross linked, semi-conducting
compound of.5 mm for 11KV
:
XLPE of thickness, 3.6 mm (Nominal) for
11KV
For Combination of black extruded semi33
conducting tape as the non-metallic part and
KV : annealed copper 0.06 mm (minimum) thick
tape lapping as metallic part. For 1 core
cable, the non-magnetic metal Armour will
act as metallic part insulation screening.
For It is same but semi-conducting tape is not
11
required
KV :
:
Black extruded PVC, Type ST-2 compound
for 33 KV and wrapped PVC tape for 11 KV
as per ISS. For 1 core there will be no inner
sheath.
:
Single layer of round galvanized steel
wires/strip for 33 KV and galvanized steel
strips/wire for 11 KV (3 core) as per IS. For 1
core, there will be non-magnetic metal
Armour.
:
Coloured PVC, type ST-2 compound to IS:
5831, extruded for both 33KV and 11KV
thickness shall be as per ISS
:
250 metres with a tolerance of ± 5% (for 3
core), 500 metres ± 5% (for 1 core)
H.S. Caps (see clause 4.13.1) (Heat
Shrinkable)
0.004
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Technical Specification
b
28
29
30
31
voltage (Uo):
Maxm. Increment of
‗tan-delta‘ between 0.5
Uo to 2 Uo at room
temp:
Partial discharge value
Impulse Tests
H.V. Tests between
Conductors &
Screen/Armour
Maxm. D.C. Rtance/Km
:
0.002
20 Pc (Maxm.) at 1.6 Uo.
170 KV for 33 KV and as per ISS for 11 KV
48 KV (rms) for 33 KV for 5 minutes and as
per ISS for 11 KV
As per relevant I.S.S
* NB the above parameters are applicable for three core and single core cable, if
not otherwise specified.
CABLE CONSTRUCTION:
4.3 XLPE underground cable is to be manufactured in continuous
catenaries process at controlled elevated temperature and pressure in
inert atmosphere with use of suitable materials for XLPE semiconducting, insulation and XLPE screen. The inner and outer semiconducting sheaths and main polyethylene insulation between the
sheaths are to be simultaneously extruded during the Triple Extrusion
Process of manufacturing and main insulation of the Cable is to be
extruded unified. The XLPE Cables in this specification does not have
any metal sheath and the short circuit rating of the cable will depend
on the conductivity and continuity of the strands of the armour wires,
which shall be ensured by guarding against corrosion.
4.4
CONDUCTOR SCREENING
4.5
A semi-conducting cross-linked polyethylene (XLPE) screening shall
be extruded over the conductor to act as an electrical shield which
together with elimination of the so called ―Strand Effect‖ prevents to
a great extent air ionization on the surface of the conductor.
4.6 INSULATION:
The main insulation of the Cable shall be extruded unfilled, chemically
cross-linked polyethylene (XLPE) inert gas cured satisfying the
requirement of ISS: 7098 (Part- II)
4.7 INSULATING SCREEN:
The screen shall be made up as given in Clause 22the metal screen
eliminates tangential stress electrostatic field surrounding the conductor
and uniform electrical stress in the insulation.
The semi conducting polyethylene (XLPE) screen shall be extruded over
the main poly ethylene-insulating wall to prevent partial discharge at the
surface of the insulation. The copper tape shall be wrapped over the semi
conducting tape or extrusion as mentioned earlier for 3 core cables. The
metal screen so formed around the cores shall be in contact with one
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Technical Specification
another as the cores are laid up at triangular configuration. For single core
cable, Aluminium wires armoring shall constitute the metallic part of
insulation screen. Conductor screening, insulation and insulation
screening shall be extruded in triple extrusion processes so as to obtain
continuously smooth interfaces.
4.8 The mechanical and chemical properties of the materials for semi
conducting screens are much more important than their electrical
properties, but for obtaining the high overall degree of electrical
properties of an E.H.V. cable, the inner and outer semi conducting,
sheaths and the main polyethylene insulation between the sheaths
shall be simultaneously extruded during the manufacturing, process
known as “triple extrusion”. The advantages are:
i) The partial discharge level at the surface of the insulation is brought
to a minimum.
ii) There will be no displacement of the semi conducting screen and
insulation during expansion and contraction due to load cycles and
bending.
iii) The semi conducting screens are easily removable during joining
and termination operations.
Note: Manufacturers not having “triple extrusion” process will
be disqualified. The Tenderer shall have to produce necessary
process line at the time of bidding.
4.9 LAYING UP:
The phase identification of the cores shall be either by colour or
numerals as per I.S.S. for 3 core cables only.
Core Colour
Numeral
Red
1
Yellow
2
Blue
3
The screen cores shall be laid up with interstices filled with PVC fillers
and taped a binder tape as to obtain a reasonably circular cable.
4.10 INNER SHEATH:
The cable core shall be supplied with bedding of PVC (Inner sheath) in
the form of extruded PVC sheath for 33 KV cables. Wrapped PVC
tapes shall be used for 11KV thickness as per clause 23 of special
technical parameters and as per relevant IS.
4.11 ARMOUR:
The cable shall be wire armoured /steel strip in case of 33KV and
wire/strip armoured 11 KV, three core cables to insure an adequate
return path for the flow of fault current and also provide suitable
mechanical protection. Steel wires/aluminum wire / steel strips of
required size in requisite number as per clause 24 of special technical
parameters shall be laid closely in the spiral formation to protect the
circumference of the cable fully and to provide adequate cores section
area for flow of maximum fault current within limits of specified
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Technical Specification
temperature rise and duration of fault. Direction of the lay of the
armour shall be opposite to that of the cable cores in case of single
core cable armour should be of non-metallic material.
4.12 OUTER SHEATH:
A reliable surving shall be necessary for maintaining conductivity of
the armour particularly under corrosive condition in the form of jacket.
Cable shall be therefore finished with extruded PVC over sheath of
thickness as per clause 25 of special technical parameters.
The quality of PVC over sheath (jacket) shall be ensured for service
reliability against moisture intrusion and shall confirm to type ST-2 of
IS : 5831.
The colour of the outer sheath shall be follows:
For 11 KV cable : Blue
The sheaths shall be protected against white ants, vermin and termites
by suitable,
durable and reliable measures.
The suppliers shall suggest suitable materials for use, in the event of
damage to the over sheath to prevent the passage of moisture along
the cable.
4.13
CABLE IDENTIFICATION:
The following shall be embossed on the outer sheath for the identification.
Manufacturer‘s Name or Trade Mark.
Voltage Grade.
Nominal section and material of conductors and number of cores.
Year of manufacture.
Inscription of length of cables at 1.0 mtr interval.
Name of purchaser LAEDCL;
Marking ―Power‖ shall be embossed throughout the length of the
cable at 10 mtr spacing.
h) Type of insulation i.e. XLPE
4.13.1 CEILING OF CABLE ENDS:
The cable ends of the cable in the wooden drum for delivery shall be
sealed with heat shrinkable caps.
a)
b)
c)
d)
e)
f)
g)
7.0
WOODEN DRUMS:
The cable shall be packed in non-returnable wooden drums.
The following information shall be marked on each drum.
a) Drum identification number.
b) Manufacturer‘s name, Trade name / Trade mark, if any.
c) Nominal sectional area of the conductor of the cable.
d) Number of cores
e) Type of cable and voltage grade with cable code
f) Length of cable in cable drum
g) Direction of rotation of drum (by means of an arrow)
h) Appox. Weight: tare: gross:
i) Year and country of manufacture
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Technical Specification
j) Purchase order number
k) Date of delivery
l) Name of the purchaser.
Drum shall be proofed against attack by white ant or termite
conforming to IS: 10418. The Drums may also be marked with ISI
certificate mark, as applicable.
Safe pulling force :
30 N/mm2 (for conductor)
8.0
Tests to be performed as per IS:7098 (part II)
Tenderer shall have to submit type test report (tested at CPRI
Bangalore/Bhupal) along with the Bid. Bidder will be disqualified for
non-submission of type test reports.
8.1
Type test all the test mentioned below are to be made as per details
given in IS:10810
a) Test on conductor
i.
Tensile test (For aluminum)
ii.
Wrapping test for aluminum
iii.
Resistance test.
b) Test for armuoring wire strips.
c) Test for thickness of insulation and sheath.
d) Physical test for insulation.
i.
Tensile strength and elongation at break
ii.
Ageing in air oven.
iii.
Hot test
iv.
Shrinkage test.
v.
Water absorption (Gravimetric)
e) Physical tests for outer sheath
i.
Tensile strength and elongation at break
ii.
Ageing in air oven.
iii.
Shrinkage test.
iv.
Hot deformation
v.
Heat shock
vi.
Loss of mass in air oven
vii.
Thermal stability
viii.
Thermal Stability
f)
g)
h)
Partial discharge test
Bending test
Dielectric power factor test
i.
As a function voltage
ii.
As a function of temperature
i) Insulation resistance (volume resistivity) test
j) Heating cycle test
k) Impulse with stand test
l) High voltage test
m) Flammability test
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8.2 The following test on screen cable shall be performed successfully
on the same test sample of completed cable, not less than 10 m.
in length between the test accessories.
a) PD test
b) Bending test followed by PD test
c) Di-electric power factor as function of voltage
d) Di-electric power factor as a function of temperature
e) Heating cycle test followed by Di-electric power factor
as a function of voltage and PD test.
f) Impulse with stand test and
g) High voltage test as per para 30 of special technical
parameters
If a sample fails in test (g) one more sample shall be taken for
this test, preceded by test (b) and (e)
8.3 Acceptance test : the following shall constitute acceptance test:
a) Tensile test (For aluminum)
b) Wrapping test for aluminum
c) Conductor resistance test
d) Test for thickness of insulation and sheath
e) Hot set test for insulation
f) Tensile strength and elongation at break test for insulation
and outer sheath
g) PD test (Screen enables) only on full drum length
h) High voltage test, and
i) Insulation resistance ( volume resistivity) test
J) Spark test on extruded un-insulated outer PVC sheath as per
provision clause no 3.2 IEC standard (Publication no.229 of
1982)
8.4 Routine test:
The routine test shall be carried out on all cables manufacturer in
accordance with this specification. The following routine test shall
be made on cable length as specified in ISS.
a) Conductor resistance test
b) Partial discharge test on full drum length
c) High voltage test as per clause 29 of special technical
parameters
8.5 Test witness
a) All tests shall be performed in presence of purchaser
representatives if so desired by the purchaser.
b) The contractor shall give at least 15 days advance notice for
witnessing such tests.
9.0
Test Certificate
9.1
9.2
Certified copies of all routine test carried out at work shall be
furnished in 6 copies for approval of the Purchaser.
The cable shall be dispatched from works only after receipt of
Purchaser‘s written approval of shop test report.
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Technical Specification
9.3
10.0
Type test certificates of the cable offered shall be furnished.
Otherwise the cable shall have to be type tested on similar rating as
per clause 10 free of any charges to prove the design.
Descriptive literatures test results etc.
The following details for the cable shall be submitted with bid
a) Manufacturers catalogue giving cable construction details and
characteristics
b) Manufacturing process in details for cables highlighting the steps
of control
i. Contamination
ii. Formation of water trees
iii. Effects of by products of cross linking
iv. Stress control etc.
c) Cross section drawing of the cable
d) Cable current ratings for different types of installation inclusive of
derating factors due to ambient temperature, grouping etc.
e) Over-load characteristics of the cable without endangering the
normal life and electrical quality of the insulation.
f) Complete technical date of the cables.
g) Type test certificate from government testing units/government
authorized testing units.
with the quality assurance plan submitted by the firm, the offer shall be
liable for rejection.
11.0
Guarantee:
The guarantee period should either be 60 (Sixty) month from the date of
commissioning or 68 (Sixty eight) month from the date of material received
at site. The tenderer shall have to replace the damage cable (electrical
damage/physical deformation) within 30 days from reporting.
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Technical Specification
3.28 TECHNICAL SPECIFICATION FOR CABLE END TERMINAL
KIT (OUTDOOR AND INDOOR)
Heat shrinkable termination Kit for 6.35/11kV XLPE ,Cable ( 1-core,300 sq mm &
185 sqmm, 3-core -120 sqmm ) both for outdoor and indoor should be as per IS :
13753 and relevant international standard. The terminal cable kit should be for
the following technical parameter of cable.
SPECIFIC TECHNICAL REQUIREMENTS:Technical parameters of the cable shall be as follows:
Sl No Particulars
Unit
1
Rated voltage of cable KV
6.35/11kV
2
Type of insulation
XLPE
3
Core
Single ,
4
Armoured /Unarmoured Armoured
5
Material of Conductor
Aluminium
6
System Voltage
11 KV Earthed
7
Highest System Voltage KV
12
8
Conductor Size
Sq. mm
300 Sq mm , 1- core
185 Sq mm , 1- core
And 120 sqmm,3-core
9
Material
Stranded Aluminium
ELECTRICAL PERFORMANCE FOR TERMINAL KIT
AC Dry withstand voltage
35 KV / 1 minute
DC withstand voltage for 30 minute
48 KV
Lighting impulse withstand voltage
75 KV
Partial Discharge
12.7 KV < 5 pc
Standard tail length for outdoor
600 mm
Standard tail length for indoor
450 mm
KIT COMPONENT
Terminal Lug
Heat Shrinkable Adhesive Lined
Terminal Sleeve
Lug Sealing Tape / Mastic
Rain Shed for 12 KV System
Anti Tracking Sleeve
Stress Control Sleeve
Stress Control Mastic
Constant Force Spring Roll
Copper Braid for Screen Earthing
Worm Drive Clip
Adhesive Line Gland Sleeve
Tinned Copper Braid duly fitted with
Terminal Lug at one end + Solder Bock
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1 No
1 No
1 Strip
2 Nos.
1 No.
1 No
1 Strip
1 No
1 No
1 No
1 No
1 No
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3.29 TECHNICAL SPECIFICATION OF CONTROL CABLES
1.0
SCOPE:
1.1
Specification calls for design, manufacture, stage testing, inspection and
testing beforedispatch, packing and delivery of Copper control cables and
Aluminum power cables for 33/11KV substations.
1.2
The control and power cables shall be ISI marked, 1.1 KV Grade. The
cores shall have a size of 2.5 sq.mm for control cables and 4 sq. mm.
power cable, using solid/stranded Copper conductor with different number
of cores as specified below:1.3
COPPER CONTROL CABLES Unarmoured
i) 12 Core 2.5 sq.mm, solid conductor
ii) 7 Core 2.5 sq.mm., solid conductor.
iii) 4 Core 2.5 sq.mm., solid conductor
iv) 2 Core 2.5 sq.mm., solid conductor
2.0
STANDARDS:
2.1
The control and power cables shall conform to the latest applicable Indian
Standards. In case bidders offer control and power cables conforming to
any other International Standards which shall be equivalent or better than
IS, the same is acceptable. Cables for which Indian Standards arenot
available, the relevant equivalent International Standards will be
applicable. Please attach photocopy of all such standards according to
which the cables have been offered
i) IS: 1554: PVC insulated (Heavy Duty) Control Cables for working
voltage & including 1100 Volts.
ii) IS: 3961: Recommended current ratings for PVC insulated and
PVC sheathed heavy duty cables
iii) IS: 4905: Methods of random sampling
iv) IS: 5831: PVC insulation and sheath of electric cables
v) IS: 8130: Conductors for insulated electric cables and flexible
cords
vi) IS: 10418: Wooden drums of electric cables
vii) IS: 10810: Methods of tests for cables
3.0
GENERAL TECHNICAL REQUIREMENTS AND CONSTRUCTIONAL
DETAILS:
3.1
Cables shall be suitable for laying on racks, in ducts, trenches, conduits
and underground
buried installation with chances of flooding by water. Cables shall
be designed to withstand mechanical, electrical and thermal
stresses developed under steady-state and transient operating
conditions as specified elsewhere in this specification.
3.2
CONTROL CABLES
Control cables shall be of 1.1 KV grade, multicore (as specified in Clause
1.3 above), PVC
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Technical Specification
insulated, PVC inner sheathed, un armoured, PVC outer sheathed
with solid copper conductor conforming to latest version of IS:
1554 or equivalent International Standards.
3.3
3.4
The conductor shall be made from high conductivity copper rods
complying with latest version of IS:613 or equivalent International
Standards. The conductor shall consist of annealed copper wires
complying with IS: 8130 with latest amendments or equivalent
International Standards.
POWER CABLES:
Power cable shall be of 1.1 KV grade, multicore (as specified in Clause
1.3 above), PVC insulated, PVC inner sheathed, PVC outer sheathed with
stranded conductor.
3.5
INSULATION:
Conductor shall be provided with PVC insulation applied by extrusion in
accordance with latest version of IS: 5831 or equivalent International
Standards. The average thickness of insulation shall be in accordance
with the IS: 1554 (Part-I) with latest amendments or equivalent
International Standards. Insulation shall be so applied that it fits closely on
the conductor and shall be possible to remove it without damages to the
conductor.
3.6
CODE IDENTIFICATION:
Colouring of insulation shall identify cores of the cables of upto 5 cores.
Following colour schemes shall be adopted:SN
1
2
3
3.7
No of Cores
2 core
4 core
7 core
Colour Scheme
Red and Black
Red, Yellow, Black, Blue and Grey
a) Two adjacent cores (counting and direction core)
in each layer, Blue and Yellow, remaining cores
Grey or in accordance with the scheme given in IS
1554
b). Cables having more than 5 cores, as an
alternate to the provision of (a) above, core
identification may be done by numbers as indicated
in latest version of IS: 1554 (PART-I) 10 core
identification.
LAYING UP OF CORES:
In multi-core cables, the cores shall be laid up together with a suitable lay, the
outer most layer shall have right-hand lay and successive layer shall be laid
with opposite lay, where necessary, the interstices shall be filled with non
hygroscopic materials.
3.8
INNER SHEATH:
The laid up cores shall be provided with inner sheath applied by extrusion. It
shall be ensured that the shape be as circular as possible. The inner sheath
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Technical Specification
shall be so applied that it fits closely on the laid up cores and it shall be
possible to remove it without damage to the insulation. Thickness of inner
sheath shall be conforming to latest version of IS: 1554 (Part-I) or equivalent
International Standards.
3.9
FILLER AND INNER SHEATH:
Filler and inner sheath shall be of the following:
Unvulcanised rubber or thermoplastic material used shall not be harder
than PVC used for insulation and outer sheath. Material shall be chosen to be
compatible with temperature ratings of the cable and shall have no deterious
effect on any other component of the cable.
3.10
OUTER SHEATH:
inner sheath in case of unarmoured multicore cables Outer sheath shall be so
applied that it fits closely over insulation / inner sheath / armouring. It shall be
possible to remove it without damage to the insulation / inner sheath. The
colour of the
outer sheath shall be black.Thickness of outer sheath insulation shall conform
to latest version of IS: 1554 Part-I or equivalent international standards.
4.0
IDENTIFICATION:
4.1
In addition to manufacurer‘s identification on cable as per clause-17.1 of
IS: 1554 (Part-I) with latest amendments, following marking shall also be
embossed over outer sheath at every three meters:-
The embossing shall be in line throughout the length of the cable
and shall be legible and indelible.
5.0
PACKING AND MARKING:
5.1
Cables shall be supplied in non-returnable drums. The surface of the
drum and outer most cable layer shall be covered with waterproof layer.
Both the ends of the cables shall be properly sealed with heat shrinkable
PVC or rubber caps, secured by ‗U‘ nails so as to elliminate ingress of
water during transportation storage and erection. Following information
should be stenciled on the drum:
-sectional area of the conductor
ble on the drum
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Technical Specification
5.2
6.0
As mentioned, the cable drum must bear relevant Indian/International
Standard certification Mark. In this connection, a certified photostat copy
of valid standard marking license rights duly attested must be submitted
along with the inspection offer as documentary evidence. In absence of
these documents, the inspection offer will not be considered.
STANDARD DRUM LENGTH:
6.1
Standard drum length for cable shall be 500/250 metres.
6.2
TOLERANCE:
Tolerance on the overall diameter of the Cable shall be ± 2 mm over the
declared value in the techanical data sheets of Guaranteed Technical
Particulars. Length per drum shall be subjected to maximum tolerance of ±
5% of the standard drum length. The Employer shall have option to reject
cable drums with shorter length. Over all tolerance in total quantity for each
type and size of cables shall be ± 2%.
7.0
TESTS:
7.1
All types and sizes of cable being supplied shall be subjected to Type
tests, Additional test,
Routine tests and Acceptance tests as specified below at the expense of
manufacturer and according to relevant standards.
7.2
TYPE TESTS AND ADDITIONAL TESTS:
It is essential to furnish all the type test reports for each type and size of cable
as stipulated in latest version of IS: 1554 (Part-I) and following Additional
Tests:
l stability test
Above tests shall be conducted in NABL approved Testing
laboratories only.
7.3
ACCEPTANCE TEST
Acceptance test shall be caried out on each type and size of cables on cable
drums selected at random as per following plan :.
Numbers of Drums in the Number of Drums to be
S.No Tests
taken as samples
1
2
3
4
5
Upto 50
51 to 100
From 101 to 300
From 301 to 500
From above 501
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Technical Specification
7.4
The following shall constitute acceptance tests :-
ageing at break of insulation
and sheath
rsion Test)
7.5
ROUTINE TESTS:
Routine test shall be carried out for each drum of cables of all types and
sizes. Following shall constitute routine tests :
st at Room Temperature
7.6
i.
ii.
iii.
iv.
While preparing cable schedules for control/protection purpose following
shall be ensured:
Separate cables shall be used for AC & DC.
For different cores of CT & PT/CVT separate cable shall be used
At least one (1) cores shall be kept as spare in each copper control
cable of 4C, 5C or 7C size whereas minimum no. of spare cores
shall be two (2) for control cables of 10 core or higher size.
For control cabling, including CT/PT circuits, 4.0 sq.mm. size copper
cables shall be used per connection
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Technical Specification
3.30 SPECIFICATION FOR 1.1 kV GRADE SINGLE CORE
UNARMOURED L.T. XLPE CABLE
1.0
SCOPE:
This specification covers design, engineering, manufacture, stage testing,
inspection and testing before supply and delivery at site of 1.1 kV grade single
core 16/25/50/95/120/185/240/300 Sq. mm. XLPE Cables for use with effectively
earthed distribution system.
1.1.
1.2.
1.3.
It is not the intent to specify completely herein all the details of the design
and construction of material. However the material shall confirm in all
respects to high standards of engineering, design and workmanship and
shall be capable of performing in continuous commercial operation in a
manner acceptable to the purchaser, who will interpret the meanings of
drawings and specification and shall have the power to reject any work or
material which, in his judgment is not in accordance therewith. The offered
material shall be complete with all components necessary for their effective
and trouble free operation. Such, components shall be deemed to be
within the scope of Bidder‘s supply irrespective of whether those are
specifically brought out in this specification and/or the commercial order or
not.
Normally the offer should be as per Technical Specification without any
deviation. But any deviation felt necessary to improve performance,
efficiency and utility of equipment must be mentioned in the ―Deviation
Schedule‖ with reasons duly supported by documentary evidences and
advantages of such deviation. Such deviation suggested may or may not
be accepted. But deviation not mentioned in ―Deviation Schedule‖ will not
be considered afterwards.
Location
The cables may be laid buried directly in ground at a depth of one metre in
average, anywhere in Assam and terminate for outdoor connection to a
distribution transformer or to overhead LT lines and also indoor connection for
indoor switchgear
2.0
STANDARDS:
2.1
The materials shall conform in all respects to the relevant Indian Standard
Specifications with latest amendments thereto.
Title
Indian
Standard No.
IS-7098 PartI/1988
Specification for Cross Linked
Polyethylene Insulated PVC
Sheathed Cables for working
Voltages Up to and including
1100V
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Internationally
Recognized
standard
IEC 502 (1983)
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Technical Specification
IS-5831/1984
IS-8130/1984
IS 3975/1979
IS-10418/1982
3.0.
IEC 502 (1983)
IEC 228 (1978)
Material conforming to other internationally accepted standards,
which ensure equal or higher quality than the standards mentioned above,
would also be acceptable. In case the Bidders who wish to offer material
conforming to the other standards, salient points of difference between the
standards adopted and the specific standards shall be clearly brought out
in relevant schedule. Four copies of such standards with authentic English
Translations shall be furnished along with the offer. . In case of conflict the
order of precedence shall be (i) IS, (ii) IEC, (iii) Other standards. In case of
any difference between provisions of these standards and provisions of
this specification, the provisions contained in this specification shall
prevail.
Moderately hot and humid tropical climate, conducive to rust and fungus
growth.
SYSTEM DETAILS :
The material shall conform to the following parameters:
Sl.
No.
1.
2.
3.
4.
5.
4.0
4.1
PVC insulation and sheath of
electric cables
Conductors for insulated electric
cables and Flexible cords
Specification for armouring
Specification for cable drum
Item
Type of Installation
System Voltage
System Frequency
No. of Phases
System of earthing
Specification
Outdoor
433 V (+10% -15%)
50 Hz +/- 5%
Three
Solidly grounded
TECHNICAL REQUIREMENTS:
MAIN FEATURES:
The power cables shall be of LT 1.1 kV Grade, stranded compacted, high
conductivity, aluminum conductor, XLPE insulated, ST-1 type extruded
PVC outer sheathed, conforming to relevant standards suitable for LT AC
three phase, 50 c/s, effectively earthed distribution system.
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Technical Specification
4.2
MATERIALS AND CONSTRUCTION:
4.2.0 SPECIFIC TECHNICAL REQUIREMENTS
Technical parameters of the cable shall be as follows
Sl
No
Cable
Size
(Sq.m
m)
Al.
Stra
nd
Min.
Min.
Min
thickne
thickne
ss of
Overall
ss of
Outer
dia
XLPE
sheath
(mm)
(mm)
(mm)
Max.
Max.
A.C
D.C
Resis
Resist tance
ance
at
at 200C 700C
(Ohm/
(Ohm
Km)
/Km)
Min.
current
carrying
capacity
at 300C
(Amps)
Gro
und
Air
Short
Ckt
curren
t/sec
(KA/1s
ec)
Min.
weigh
t.
Kg/K
m
1
25
7
0.9
1.8
11.0
1.200
1.540
96
98
2.4
169
2
120
19
1.2
1.8
19.0
0.253
0.325
225
268
11.3
538
3
240
Bc,x
4.2.1 CONDUCTOR:
The cable conductor shall be made from stranded aluminum to form
compacted shaped conductor having resistance within the limits specified
in IS-8130/1984
4.2.2 INSULATION:
The XLPE insulation shall be suitable for the specified system voltage. The
manufacturing process shall ensure that the insulation is free from voids.
The insulation shall withstand mechanical and thermal stresses under
steady state as well as transient operating conditions. The extrusion
method shall give smooth surface of insulation. The insulation shall be so
applied that it fits closely on the conductor and it shall be easily possible
to remove it without damaging the conductor.
4.2.3 OUTER SHEATH:
Extruded PVC outer sheath of black colour shall he applied with suitable
additives to prevent attack by rodents and termites. Outer sheathing shall be
designed to offer high degree of mechanical protection and shall also be heat, oil,
chemical, abrasion and weather resistant. Common acids, alkalies, saline
solutions etc., shall not have adverse effects on the PVC sheathing material used.
4.2.4 CONSTRUCTION:
1)
All materials used in the manufacture of cable shall be new, unused and of
finest quality. All materials shall comply with the applicable provisions of the
tests of the relevant Standards.
2) The PVC material used in the manufacture of cable shall be of reputed
make.No recycling of the PVC is permissible. The purchaser
reserves the right to ask for documentary proof of the purchase of
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Technical Specification
various materials to be used for the manufacture of cable and to check
that the conductor is complying with quality control.
4) Cables shall have suitable fillers laid up with the conductors to provide a
substantially circular cores section before the sheath is applied. Fillers shall
be suitable for the operating temperature of the insulation & compatible with
the insulation material
4.2.5 CURRENT RATING:
The cables shall have current ratings and derating factors as per relevant
Indian Standards. The current ratings shall be based on maximum
conductor temperature of 90 deg. C with ambient site condition specified
for continuous operating at the rated current.
4.2.6 OPERATION:
Cables shall be capable of satisfactory operation, under a power supply
system frequency variation of +/- 5 c/s, voltage variation of +10% or-15%.
Cables shall have heat and moisture resistance properties; these shall be
of type and design with proven record on Distribution Network service.
4.2.7
LENGTH:
The cable shall be supplied in wooden drums and the standard drum length shall
be as follows1x25 mm2
1000 meters +/- 5%
1x120 mm2
500 meters +/- 5%
1x240
Substandard drum length of not less than 100 meters upto a maximum of 5% of
the quantities ordered shall be accepted. However substandard drum length upto
a maximum of 5% shall be acceptable only in a particular lot offered for
inspection
4.2.8
IDENTIFICATION:
For identification of individual cores, coloured strips of red, yellow and blue
colours respectively shall be used on the cores to identify phase conductors as
per relevant ISS.
4.2.7 EMBOSSING:
The cable shall be embossed through out the length with the name of the
manufacturer and the letters "Property of APDCL., Specification No., voltage
grade with cable size and the year of manufacture". The embossing shall be
done only on the outer sheath, the distance between any two consecutive
embossings shall not be more than 2 Meter. The cable shall also be embossed
(clearly visible) for the verification of its length at intervals of 1 Meter say 1,2,3 up
to full length.
4.2.8 GUARANTEED TECHNICAL PARTICULARS:
The guaranteed technical particulars as detailed in the specification
annexure-I shall be guaranteed and a statement of guaranteed technical
particulars shall be furnished in the format along with the bid without
which the Bid shall be treated as Non -Responsive.
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Immediately after completion of the electrical tests (during
routine/acceptance tests), the ends of the cable shall be enclosed by
rubber/PVC caps of wall thickness not less than 2.5 mm and then sealed
by non hygroscopic material (the cores being suitably insulated from the
cap). The cap shall be of robust construction and tight fit, and it shall have
the trademark of the manufacturer embossed thereon
5.0.
5.1
TESTS:
Type Test:
The material offered shall be fully type tested at independent test
laboratories by the Bidder as per the relevant standards but test reports
shall not be more than five years old from the date of opening of bid. The
bidder shall furnish complete set of following type test reports along with
the bid. The bids received without these type test reports shall be
treated as Non-responsive.
1.
2.
3.
4.
5.
6.
Tests on conductors
Test for thickness of insulation and sheath
Physical tests for insulation
Physical tests for outer sheath
Insulation resistance test
High voltage test
5.2.
Acceptance and Routine test: All acceptance and routine tests as
stipulated in the relevant standards shall be carried out by the supplier in
presence of purchaser's representative.
6.0
INSPECTION:
6.1
The inspection shall be carried out by the purchaser‟s representative during
manufacture and before dispatch. The supplier shall keep the purchaser informed in
advance, about the manufacturing programme so that arrangement can be made for
inspection.
The manufacturer shall grant free access to the purchaser‘s representative, at a
reasonable time, when the work is in progress. Inspection and acceptance of any
equipment under this specification by the purchaser, shall not relieve the supplier
of his obligation of furnishing the equipment in accordance with the specification
and shall not prevent subsequent rejection if the equipment is found to be
defective.
6.2
All Acceptance tests and inspection shall be made at the place of manufacturer
unless otherwise especially agreed upon by the Bidder and purchaser at the time of
purchase.
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The purchaser reserves the right to insist for witnessing the acceptance/
routine testing of the bought out items. The supplier shall give 15 days (for
local supply)/ 30 days (incase of foreign supply) advance intimation to
enable the purchaser to depute his representative for witnessing the
acceptance and routine tests. Material shall be dispatched only after
getting the dispatch authorization from Inspectors representing purchaser,
after successful testing.
6.3
If successful type tests have been carried out on the offered design
during last five years (counted from the date of tender opening), repetition
of type tests is not required.
On the other hand, if the offered design is not type tested during last five
years, the cable shall be subjected to all type test in accordance with IS:
1554 (Part-I)/1988 and amendment thereof at recognized test house of
repute. All charges/fee/transportation etc. to conduct these tests shall be
borne by Contractor.
Regular supply of the material shall commence only after successful type
testing and dispatch authorization from the competent authority.
However, the purchaser reserves the right to get cable type tested at any
stage during the currency of contract at his own expenses in any reputed
test house. The transportation and arrangement of testing of sample to
test laboratory shall be the responsibility of the contractor.
6.4
Routine tests report shall be sent by the manufacturers with their offer for
inspection, the following acceptance tests as laid down in the referred ISS (with
latest amendments) shall be carried out by the inspecting officer of the APDCL on
Samples selected at random as per Appendix `A ‗ in IS-1554 (Part-I) 1988.
1. Tests on conductor
a) Tensile test
b) Conductor resistance test
2. Test on armoring strips:
a) Measurement of dimension
b) Tensile test
c) Elongation test & winding test
d) Zinc coating
3. Test for thickness of insulation and sheath
4. Tensile strength and elongation
at break of insulation and sheath
5. Insulation Resistance Test
6. High voltage test at room temperature
1988
Reference to I.S.S.
IS: 8130-1984
IS: 8130-1984
IS: 3975 – 1979
IS: 3975 – 1979
IS: 3975 – 1979
IS: 2633 – 1984
IS: 5831 – 1984
IS:5831 – 1984
IS: 5831 – 1984
IS: 1554 (Part-I) –
In addition to above, length/weight check and bending test on one drum
per inspection shall also be carried out by the inspecting officers for which
contractor will make all necessary arrangements and provide all necessary
facilities at his own cost.
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Technical Specification
7.0
CALBE DRUMS:
The cables shall be supplied in non-returnable substantially lagged
wooden drums of heavy construction suitable for transportation by goods
train or truck and for storage at site. The wood used for construction of the
drum shall be properly seasoned and sound and wood preservative shall
be applied to the entire drum. All ferrous parts shall be treated with a
suitable rust preventive finish or coating to avoid rusting during transit or
storage. The drum shall also conform to specn. No. IS: 10418-1982 with
latest amendment thereof.
Each drum shall have the following information marked on it with
indelible ink alongwith other important information including technical data:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Property of APDCL & Specification No. –
Designation of consignee & destination railway station.
Drum Number.
Aluminium Core Cable.
Cable rating eg. Voltage grade, No. of cores, sizes etc.
Height of empty drum.
Length of Cable.
Gross weight of drum with cable.
Year of manufacture.
8.0
PACKING AND TRANSPORT:
All the material covered under this specification shall be adequately
packed for transportation by Rail/Road. A layer of waterproof paper shall
be applied to the surface of the drums and over the outer cable layer. A
clear space of atleast 40 mm shall be left between the cable and the
laggings. The packing shall be adequate to protect the cable from
damage, in transit and contractor shall be responsible for it and make
good at his own expense any and all damages due to improper packing
etc.
9.0
VARIATION OF QUANTITY:
The supplied quantity can vary within Plus/Minus 1% of the ordered
quantity.
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Technical specification
3.31 TECHNICAL SPECIFICATION FOR STAY SET (HT )
1.0 Scope:
1.1.
This specification covers the design, manufacture testing at
manufacturer's works, transport to site, insurance, storage, erection
and commissioning of the Stay Sets (HT) required from the distribution
lines at designated locations.
2.0 Standard:
2.1.
All the materials of stay sets shall comply in all respects with the
requirements of the latest edition of the relevant Indian or British Standard
specification except in so far as they are modified this specification.
3.0 Design Consideration:
3.1.
Stay Rods shall be Galvanised and shall be of circular Cross-section
with bow, thimble, nuts and bolts. The Rods shall be threaded at one end up
to a minimum of 30 cm length and shall be complete with Galvanised M.S.
Anchor Plates with all necessary accessories. All parts shall be heavily
galvanised.
4.0 Testing:
4.1.
Type and Routine Tests should be carried on different components of
each stay sets as per relevant Indian Standard specification and certified
copies of the above should be submitted along with the tender.
5.0
Schedule Requirement:
Stay sets complete with Thimble bow stay Rod/Anchor plate with nuts etc. and made
of Rolled mild Steel Rod and plates as per detailed given below:
5.1. Anchor Plate:
I)
II)
III)
IV)
V)
Thickness not below 5 mm.
Size not below 300 mmX300 mm with smooth edges (for HT)
Well galvanised
Materials M.S. Rolled plate
About 20 mm square hole at centre for locking the plate with the Anchor
Rod (for HT)
5.2. Anchor Rod:
VI) Length 1800 mm or above
VII) Threaded length 30 cm or above
VIII) Diameter 18 mm or above (for HT)
IX) Anchor plate and head: square size 30mm X 30mm with thickness 25
mm having matching square size shank for locking the Anchor plate.
X) One ratched lock nuts, grooves must match the grooves at bow flange
XI) One check nut.
XII) Materials H.S.
XIII) Component well galvanised with extra care for the threaded portion.
XIV) Both lock and check nuts should be matching to the Anchor Rod
thread such that punching of thread after assembly at site safeguards
them against removal.
5.3. Thimble: The match bow diameter and bend should be well galvanised.
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Technical specification
5.4. Bow: Rod diameter 12mm/16mm or above overall length 35cm/40cm or
above. Flange with well formed locking grooves matching the locking nut,
bow ends will be riveted securely with the flange. All items to be galvanised.
6.0 Inspection:
6.1.
All tests and inspections shall be carried out at the place of
manufacturer unless otherwise agreed by the purchaser and the
manufacturers at the time of purchase. A manufacturer shall afford the
inspector representing the purchaser or third party nominee, all reasonable
facilities, without charge to satisfy that the materials are being purchased as
per specification. The purchaser reserves the right to have the test carried
out at his cost by an independent agency, whenever there is dispute
regarding the quality of the materials supplied.
7.0 Marking
7.1.
The equipments shall be marked with name of manufacturer, year and
name of project.
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Technical specification
3.32 TECHNICAL SPECIFICATION FOR G.I. STAY WIRE
1.0
Scope
The specification covers design, manufacturing and testing, transporting to
site, insurance, storage, erection and commissioning of G.I. Stay Wire
7/10SWG and 7/14SWG.
2.0
Materials.
The wire shall be manufactured from steel, made by any suitable process and shall
not contain sulphur and phosphorus exceeding 0.065 percent each.
The wires shall be coated with Zinc Grade Zn 98 of IS:209-1966
The general requirements for the supply of Galvanized stay strand shall be in
accordance with IS:1387-1967
3.0
3.1
Construction
Grades: The wire shall be of Grade-I and tensile strength range 45 up to and
including Kg/mm
The Galvanized stay strand shall be of 7/2 mm and 7/3.15 mm. the lay of the strands
shall be of the length of 7/2 mm and Tables-I of IS: 2141-1963. the wires shall be so
stranded together that when and evenly distributed pull is applied at the end of the
completed strand each wire will take equal share of the pull.
The length of the strand which may be supplied without joints in the individual wires
comprising it, depend on the length of wire which may be carried by the bobbin in a
normal stranding machine. The normal lengths of strand which shall be supplied
without joints in the individual wires, excluding welds made in the rod before drawing
shall be as given below. The lengths may be exceeded by agreement between the
manufacturer and the purchaser.
Diameter of wire in strand
Normal length without joints of weld
3.15 mm
1000 M
2.0 mm
3000 M
In cases where joints are permitted, they shall be made by welding of brazing joints in
the same wire shall be separated by a length of not less than that shown in 3.3 and
joints in different wires in a strand shall not be less than 20 M apart.
3.2
3.3
3.4
4.0
4.1
Freedom from Defects :
Each coil shall be warranted to contain no weld joint or splice other than in the rod
before it is drawn and those permitted in 3.4. The wire shall be circular and shall be
free scale, irregularities imperfections flaws splits and other defects. The Zinc coating
shall be smooth, even the bright.
5.0
5.1
Tests:
Chemical Analysis: Unless otherwise agreed to between the purchaser and the
supplier, the chemical analysis be carried out.
5.2
Tensile Test: The wire when tested in accordance with IS: 1521-1960, on gauge
length of 100 mm shall have the minimum tensile strength specified in Tables 1 of IS
: 2141/1968 according to the grade of the wire.
5.2.1 The tensile strength of the finalised strand shall be not less tI~an 93 percent of the
aggregate of the single wires.
5.3
Delivery test: The wire shall be subjected to the wrapping test in accordance with IS :
1755/1961. When wrapped eight times round its own diameter and on being
subsequently strengthened the wire shall not break or split.
5.3.1 Coating test: The uniformity of Zinc coating shall be tested by the method specified
in IS : 2633/1964. The wire shall withstand the number or dips as specified in IS :
4826-1968.
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Technical specification
6.0
6.1
6.2
7.0
Marking:
Each coil shall be provided with a label, fixed firmly on the inneJ part of the coil,
bearing 'the following information.
a. Manufacturer's name or trade mark
b. Lot number and coil number
c. A brief description and quality of the materials.
d. Weight and
e. Any other particulars specified by the purchaser
f. Name of the project TDF.
The label may also be marked with the ISI certification mark.
Inspection:
The test should be carried out in presence of the inspecting officer deputed by
purchaser or third party nominee and the test should be in conformity with relevant
IS.
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3.33 TECHNICAL SPECIFICATION OF HT GUY INSULATOR
1.0
Scope
This specification covers design, manufacture, testing, transport to site,
insurance, storage, erection and commissioning of the strain type porcelain
Guy Insulator used in distribution overhead power lines.
5.0
Standard
This insulators shall comply with Indian Standard specification IS: 5500/1969 and as
amended from time to time except where they conflict with the requirements in this
specification.
Offers conforming to any other internationally accepted standard which ensure equal
or higher quality than the standard mentioned will be acceptable.
6.0
General Requirements
This porcelain shall be sound, free from defects, thoroughly vitrified and smooth
glazed.
The design of the insulator shall be such that stresses to expansion and contraction
at any part of the insulator shall not load to its deterioration.
The glaze, unless otherwise specified, shall be brown in colour. The glaze shall cover
the entire porcelain surface parts except those areas that serves as supports during
firing or area otherwise required to be left unglazed.
7.0
Insulator Characteristics
The Guy Strain Insulators shall have the electrical and mechanical characteristics as
shown below:
H.T. Strain Type Porcelain Guy Insulator
1) Length
140 mm
2) Diameter
85 mm
3) Cable hole dia
25 mm + 1.5
4) Minimum failing load
88 KN
5) Creepage distance
48 mm
6) Dry one minute power frequency withstand 27 KV (rms) voltage
7) Wet one minute power frequency withstand 13 KV (rms) voltage
8.0
Test
All insulators shall comply the following test as per IS : 5300
A) Routine test:
The following shall be carried out as., routine test.
a)
Visual Examination
Every insulators shall be visually examined. The insulators shall be free from physical
distortion of shape and defects, and thoroughly verified and smoothly glazed. They
should be free from cracks or any other defects likely to be prejudicial to the
satisfactory performance in service.
b) Type test:
The following shall constitute the type test and those shall be conducted in the order
given below:
i. Visual examination
ii. Verification of dimensions
iii. Temperature cycle test
iv. Dry one minute power frequency voltage withstand test
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Technical specification
v. Wet one minute power frequency voltage withstand test
vi. Mechanical strength test
vii. Porosity test.
The number of samples for type test are to be agreed to between the purchaser and
the supplier.
c) Acceptance Test (to be conducted in the following order)
i. Verification of Dimensions
ii. Temperature cycle test
iii. Mechanical strength test
iv. Porosity test
The number of samples for acceptance test shall be in accordance to IS: 5300.
d)
Type test certificate from National Test House/ Govt. recognized institutions/
Govt. recognized public Testing Laboratories are also to be submitted along with the
offer, failing which the offer is liable for rejection.
9.0
Marking
Each insulator shall be legibly and indelibly marked to shown the following:
a.Name of trade mark of the manufacturer
b.Year of manufacture and name of project TDF 2010-11
Marking on porcelain shall be printed and shall be applied before firing. Insulators
may also be marked with the ISI certification mark.
10.0 Inspection
All tests and inspections shall be carried out at the place of manufacturer unless
otherwise agreed by the purchaser and the manufacturer at the time of purchase.
The manufacturer shall afford the inspector representing the purchaser or the third
party nominee, all reasonable facilities, without charge, to satisfy that materials are
being furnished in accordance with the specification. The purchaser reserves the
right to have the test carried out at his own cost by an independent agency whenever
there is dispute regarding the quality of materials supplied.
11.0 Drawing
Drawing specifically showing all dimensions is to be submitted along with technical
bid.
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Technical specification
3.34 TECHNICAL SPECIFICATION FOR G.I. WIRE
1.0
2.0
3.0
4.0
4.1
4.2
5.0
Scope
This specification covers the manufacturing, testing at works, transport to site,
insurance, storage, erection and commissioning of Galvanised Iron Wire of sizes 4
mm and 5 mm diameter.
General requirements
It relating to the supply of mild steel wire shall be as per IS: 1387/1967 and the
wire shall be drawn from the wire rods conforming to IS: 7887/1975.
The requirements for chemical composition for the wires shall conform to
IS:7887/1975.
Mild steel wire for General Engineering purpose shall be of following sizes:
I)
4mm - diameter (8 SWG)
II)
5mm - diameter (6 SWG)
Tolerance permitted on the diameter of wire shall be as per Table -1 of
IS:280/1978.
Climatic Conditions
The cross arms should be suitable for the climatic condition mentioned In these
bidding documents:
Mechanical Properties
Tensile Test: Tensile strength of wire when tested in accordance with IS:
1521-1972, shall be within the limits given in Table-2 of IS: 280/1978.
Wrapping Test: Wires shall be subjected wrapping test in accordance with IS: 17551961. The wire shall withstand without breaking or splitting. being wrapped eight
times round its own diameter and subsequently straightened.
Surface finish
a. The wire shall have galvanized finishes. The galvanized coating of steel wire
shall conform to the requirements for anyone of the types of coatings given in IS:
4826-1968 as per agreement with the purchaser.
b. The coating test for finishes other than galvanized, copper coated or tinned shall
be subject to between the purchaser and the manufacturer.
c. Unless otherwise agreed to the method of drawing representative samples of the
material and the criteria for conforming shall be as prescribed in Appendix (A) of
IS: 280/1978.
d. All finished wires shall be well and cleanly drawn to the dimensions specified.
The wire shall be sound, free from splits, surface flaws, rough jagged and
imperfect edges and other harmful surface defects.
e. Each coil of wire shall be suitably bound and fastened compactly and shall be
protected by suitably wrapped.
6.0
Marking
Each coil of wire shall be marked legibly with the finish size of wire, lot number and
trade mark of the name of the manufacturer. The material may also be marked with
the ISI certification mark and name of the project TDF.
7.0
INSPECTION
Inspection may be carried out by the purchaser or third party nominee at any stage of
manufacture. The supplier shall grant free access to the purchaser's representative or
third party nominee at a reasonable time when the work is in progress. Inspection
and acceptance of any equipment under this specification by the purchaser shall not
relieve the supplier of his obligation of furnishing equipment in accordance with the
specification and shall not prevent subsequent rejection if the equipment is found
defective.
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Technical specification
3.35 TECHNICAL SPECIFICATION AND SCOPE OF WORKS OF Gas
filled LT capacitor unit
1.0 SCOPE
This specification covers design, manufacturing, testing, insurance, transportation,
supply and installation of three phase, delta connected, 50 Hz., outdoor type, self
healing, metalised polypropylene design, cylindrical LT shunt capacitor units filled
with inert gas, intended for power factor improvement and to be installed on LT side
of three phase distribution transformers of various ratings by way of suitable clamp.
Gas filled capacitor unit shall be ISI Marked along with IP54 degree protection
level.
2.0 STANDARDS
Unless otherwise stipulated in the specification the capacitor unit shall generally
comply with IS:13340 / 1993 (reaffirmed 1998) for self healing type, IS: 12672 / 1989
for internal fuses and internal over pressure disconnectors for shunt capacitors and
1S: 13341 / 1992 for requirements for ageing test, self healing test and destruction
test on shunt capacitors of the self healing type for AC power systems having rated
voltage up to and including 650 V (with latest version / amendments). The
specification supercedes requirements in IS wherever applicable.
3.0 CLIMATIC CONDITIONS
The equipment to be supplied against this specification shall be installed on one of
the pole of distribution transformer DP structure and therefore shall suitable for
satisfactory continuous operation at site under the following tropical climatic
conditions:
a) Maximum temperature of air in shade
: 55°C
b) Minimum temperature of air in shade
: (-) 5 °C
c) Maximum relative humidity
: 95%.
d) Minimum relative humidity
: 10%.
e) Height above main sea level
: up to 1000 meters
f) Average number of thunder storm
: 40 days per annum.
f) Dust storms likely to occur
: from March to July.
h) Average annual rain fall (depending on area) : 10 to 100 cms
i) Number of months during which tropical monsoon: 4 Months, June to Sept.
Conditions prevail
3.1 SYSTEM DETAILS / PARTICULARS
The distribution transformers are connected to the 11 KV network on its HT side
while LT side is connected to the 440 Volts LT network
i. Nominal voltage
: 440 / - 10% Volts
ii. Rated Frequency
: 50 + /- 3% Hz
iii. No. of phases
:3
3.2 RATING
The stated output of capacitor units in KVAR at frequency of 50 Hz for upper limit of
temperature category of 55 deg., shall be as per relevant Annexure of the IS.
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Technical specification
3.3 RATED VOLTAGE
The rated voltage capacitor units shall be 440 Volts. The fluctuation in supply voltage
as specified in IS: 585 /1962 and IS: 12360 / 1985 (with latest amendments) shall not
affect normal working of the equipment.
3.4 GENERAL TECHNICAL REQUIREMENT
The capacitor element used in unit shall have multilayer metallised polypropylene
film (MPP) having low loss dielectric and impregnated with such impregnant, which
shall have high dielectric constant, low viscosity and high chemical stability. The
impregnant should be inert gas. Concentric winding shall be adopted to form three
phases. The PP film should be a product manufacture by a company of international
repute and should have such design that higher current carrying capabilities can be
acheived. Active binding element shall be properly heated and than vacuum dried
prior to encapsulation in gas impregnation. The contact area must be carefully
prepared so as to achieve high in rush current and long life. The capacitor unit shall
have over pressure disconnector protection. Discharge resistance shall reduce the
residual voltage to less than 50 volts within one minute as required by IS: 13340. For
easy identification of damaged units with naked eye; Visual Fault Indicator
shall be provided.
3.5 CONSTRUCTION
The capacitors should have 3 Phase having different KVAR rating, cylindrical unit
housed in cylindrical aluminum container. The height and diameter of the capacitor
shall be as per relevant standard. At the base of capacitor unit suitable arrangement
for earthing preferably in form of M-12 size stud bolt having 16 mm outer (projected)
length with toothed washer hexagonal nut & two numbers spring washer shall be
provided in such a way that it should also serve facility for clamping capacitor unit on
LT Poles. The outgoing terminals of capacitor unit should be covered by a UV
resistant cap. The capacitor & unit with the cap should conform to IP:54 degree of
protection.
3.6 INSTALLATION
LT Capacitors are to be installed on one pole of DTR Double-Pole Structure or on LT
Pole through suitable clamping arrangement. Clamp should have enough strength to
hold the capacitor for long period. A suitable size of ISI marked with UV protection
wire of reputed makes like Phinolex or Anchor, per phase should be used for
connecting the capacitors with DTR.
3.7 PERMISSIBLE OVER LOADS
For capacitors specified in this specification, the maximum permissible over loads
shall not exceed anyone of the limits given in (i) and (ii) below as conforming to IS:
13340 / 1993 (re-affirmed 1998):
i) Voltage: The permissible over loads shall not exceed limits set by IS: 13340 for self
healing type capacitors.
ii) Current: Capacitor units shall be suitable for continuous operation at r.m.s. Line
current 1.30 times the current occurs at rated sinusoidal voltage and rated
frequency, excluding transients (as per IS: 13340 for self healing type capacitors).
iii) Inrush current: should be 200 times I nominal current.
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Technical specification
3.8 CAPACITOR LOSS
The total capacitor loss excluding discharge resistor and cable should not be more
than 0.5 watt / KVAR for self-healing type capacitors using metallised polypropylene.
The bidder must state the loss of the capacitors offered.
3.9 CAPACITOR LIFE
Life expectancy of capacitors shall not be less than 1,15,000 hours.
3.10 RATING PLATE
A rating plate shall be provided on each unit with complete information marked
indelibly in accordance with clause 10 ‗Marking‘ of IS: 13340 (with latest
amendments). The words ―PROPERTY OF CSPDCL‘ shall he marked conspicuously
on each capacitor unit with inedible marking along with details of S.No., P0 No. &
Date, Rating etc.
3.11 SAFETY RQUIREMENT
i) Capacitor unit shall be provided with directly connected discharge device metal
oxide varistors (MOV) or resistors of suitable energy handling capacity and as per IS:
13340 /1993 (with latest amendment) for self-healing type capacitors. It should be
ensured that there must be no switch, fuse or any other isolating device between the
capacitor unit and the discharge device.
ii) The discharge device shall reduce the residual voltage from the crest value of the
rated voltage to 50 V or less within one minute after the capacitor is disconnected
from the source of supply.
iii) Capacitor shall comply with the relevant general safety regulations for power
installation as per Indian Electricity Rules 1956.
3.12 MONITORING FACILITY
For easy identification of damaged units with naked eye; Visual Fault Indicator shall
be provided.
3.13 TESTS
3.13.1 Routine Tests:
All individual capacitor units shall be subjected to the routine tests at the
manufacturer‘s works (at the cost of manufacturer) for the test specified in clause no.
12.1.1 of IS: 13340/1993. A certificate detailing the results of such tests shall be
furnished by the supplier along with inspection call to the purchaser.
3.13.2 Type Test:
All the tests indicated at clause no. 12.2.2 of IS: 13340 / 1993 with latest
amendment, if any shall constitute the type tests. All the type tests shall be carried
out at the Govt. / Govt. laboratories accredited by National Accreditation Board of
Testing and Calibration Laboratories (NABL) in accordance with the IS: 13340/ 1993.
3.13.3 IP: 54 Test:
Capacitors should be tested for IP54 as per IS 12063- 1987.
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Technical specification
3.14.4 Routine / Acceptance Tests:
The inspecting officer will carry Out the routine / acceptance tests specified as under
as per IS:13340 / 1993 (with latest amendment) for self-healing type capacitors.
i.
Visual examination.
ii.
Sealing test.
iii.
Measurement of capacitance and output.
iv.
Insulation resistance test between terminals & capacitor container
v.
Capacitor loss tangent (tan delta) measurement at elevated temperature.
vi.
AC Voltage test between terminals.
vii.
AC Voltage test between terminals and containers.
viii.
Test for efficiency of discharge device.
ix.
Any other test as per relevant IS.
The bidder shall furnish copies of type test reports as per relevant IS for the
equipment offered or higher rating along with tender. The offer received without type
test reports shall be ignored.
The equipment offered shall be fully type tested as per the relevant standards
for the entire type test specified in the IS at the Govt. / Govt. approved testing
laboratories accredited by NABL. Type test shall not be older than 5 years from date
of submission of tender.
In respect of successful bidders, the purchaser reserves the right to demand
repetition of some or all the type tests in the presence of purchaser‘s representative.
3.15 PACKING AND FORWARDING
i. The equipment shall be suitably packed in order to avoid damages / losses or
breakage during transit or handling. Each capacitor unit may be suitably packed in
the first instance to prevent ingress of dust and moisture and than placed in cushion
cartoon of suitable material to prevent damage due to shocks during transit. The lid
of cartoon may be suitably sealed. A suitable number of sealed cartoons may be
packed in a case of adequate strength with extra cushioning, if considered
necessary. The cases may than properly sealed against accidental opening in
transit. The packing cases may be marked to indicate the fragile nature of the
contents.
ii. The following information shall be furnished with the consignment: a. Name of the consignee.
b. Details of consignment.
c. Destination.
d. Total weight of consignment.
e. Sign showing upper / lower side of the crates.
1. Sign showing fragility of the material.
g. Handling and unpacking instructions.
h. Bill of material indicating contents of each package & spare material.
iii. The supplier shall be responsible for all the damages / losses due to improper
packing. Replacement shall be made free of cost regarding material pointed out
defective by the consignees.
3.16 DRAWINGS AND DOCUMENTATION
Tender must accompany relevant catalogues and sectional drawing showing
necessary details of the equipment offered and installation arrangements along with
bill of material. One copy of the dimensional drawing and internal constructional
drawing shall be furnished with tender.
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Technical specification
3.17 RATINGS OF CAPACITORS TO BE INSTALLED
LT Capacitors are to be installed as per details given hereunder:XMER
Rating
25 kVA
63 kVA
100 kVA
>100
kVA
TOTAL
No. of
XMER
6446
16699
10618
4426
No. of XMER & kVAR
rating for Rural area
6446 (5 kVAR)
15029 (12 kVAR)
8494 (20 kVAR)
0
No. of XMER & kVAR
rating for Urban area
0
1670 (5 kVAR)
2124 (10 kVAR)
4426 (20 kVAR)
38189
Thus, number of capacitor rating-wise are to be installed as per details given below:S
N
1
2
3
Particulars
5 kVAR
No. of XMER in rural 6446
area,
where
capacitors are to be
installed.
No. of XMER in 1670
urban area, where
capacitors are to be
installed.
Total No. of XMER
8116
10 kVAR
12 kVAR
20 kVAR
0
15029
8494
2124
0
4426
2124
15029
12920
3.18 GUARANTEED TECHNICAL PARTICULARS
The Guaranteed Technical Particulars in prescribed Performa shall be furnished duly
filled along with the tender.
S C H E D U L E – IV
SCHEDULE FOR GUARANTEED AND GENERAL PARTICULARS FOR EACH RATING
OF CAPACITORS
Sr.
No
1
Description
2
3
4a
4b
4c
4d
Manufacturer‘s Name & Trade mark
Country of origin
Whether ISI marked
ISI mark License No.
Valid up to
Rating covered in license (enclosed
copy of license)
Shape of basic element
Type of dielectric film used
Thickness of PP film (Micron)
Voltage stress (volts/micron)
5a
5b
5c
5d
Details
Type / Rating
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5e
(i)
(ii)
6
(i)
(ii)
7
8
9
10
10a
11
(i)
(ii)
12
13
14
15
16
17
18
19
21
22
23
24
25
26
27
28
Voltage rating of each pack
Without thickness of impregnate
With thickness of impregnated
Dielectric used
Inflammable
Type of dielectric
Type of impregnated used
Rated capacity of each capacitor unit
Rated voltage of capacitor unit
Maximum temperature rise
Hot spot temperature rise
Voltage proof test
Test voltage between terminals
Test voltage between terminals &
container.
Weight of each capacitor unit
Material & dimension of container
Whether protective cap & insulation
block is suitable for outdoor
operation/installation and safety for
accidental contact provided
Whether pressure sensitive device for
internal faults provided
Life expectancy in hours & percent
failure rate
Overload capacity (voltage/current)
Dielectric loss per KVAR
Total loss per KVAR
Percentage tolerance on capacity
Percentage drifting capacitance over
a period of 5 year
Details of type/routine &acceptance
testing facilities available
Characteristics of discharge devices
(residual voltages & discharge time)
Whether capacitor with and
installation accessories are IE rules
compliant
Characteristics of gas used
Whether capacitor unit suitable for
mounting in any desired position
Details of mounting arrangements
(Drawing should be enclosed)
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3.36 TECHNICAL SPECIFICATION 11 KV UTOMATICALLY
SWITCHED CAPACITOR BANKS AT 33/11KV
SUB-STATIONS
FOREWORD:
11 KV capacitor bank controlled by manually switched devices
like Isolators/Load Break Switch or circuit breakers has the
following disadvantages as compared to modern automatically
switched Capacitor Bank:
• The ON/OFF operation of capacitor bank depends on one
operator and it is difficult to regulate switching the
capacitor bank as per varying load condition resulting in
sub-optimal utilization of the investment made.
• Quantum of reactive compensation in circuit can not be
controlled in small steps.
•
This results in over compensation or under compensation of
reactive power at varying load conditions.
• Difficult to keep a close watch on various parameters such
as current in each phase of the capacitor bank, system
voltage, unbalanced operating conditions etc., to provide
adequate protection
to the capacitor
bank against
abnormal operating conditions thereby increasing the
chances of capacitor failures.
• The scheme eliminates conventional components like Electro
Magnetic
Relays etc.
• A modern SF6 or Vacuum type circuit breaker is a costly
equipment and designed for isolating faults rather than for
reactive power switching duty. The breaker, there-fore is not
ideal equipment for control of capacitor bank which may have
to be operated a large number of times in a day.
To overcome above shortcomings use of 11 KV Capacitor
Switches
(instead
of circuit breakers)
for operation of
capacitor bank divided into suitable steps for optimum
utilization is being adopted.
The Circuit Breaker is replaced by no. of Capacitor Switches for
utilizing the capacitor bank in
various steps as required.
However it should be noted that main incomer to capacitor
bank shall be circuit breaker only.
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1. SCOPE:
1.1 This specification covers design, engineering manufacture,
testing at manufactures works, supply and delivery, erection,
testing and commissioning of 11 KV outdoor types 3 phase
capacitor banks at site for out door installation along with
necessary equipments in all respect.
1.2 The specification covers 3 phase, 50 Hz, Out door type
automatically
switched
capacitor bank intended for installation at 11 KV side of 33/ 11
KV power transformers in various sub-stations. The equipment
covered in this specification comprises of Capacitor banks in
steps, 0.2 % Series Reactors, Capacitor switch, HT Fuses, RVT,
CT etc.
2.Climatic condition:
1 . Max. ambient air temperature
2
2.
Min.
ambient
air
3.
Average
Daily
Max.
ambient
temperature
4. Max.
yearly
weighed average
ambient
temperature
5.
Max.
altitude above mean sea level
6.
Minimum Relative Humidity (%aqe)
(Meters)
7.
Max. Relative Humidity (%aqe)
8.
Avq, No. of Rainy days/year
9.
Avq, annual rainfall
10. Maximum wind pressure
500C
5C C
40CC
32CC
1000
26
95
120
900 mm
195 Kq./m Sq.
3.0Applicable Standard:
Unless otherwise modified in this specification, the capacitor shall
comply with latest version of IS: 13925:1998. The other
components such as Vacuum Circuit Breaker, Isolator, CT, PT,
LA, Capacitor Switches, HT fuses, Series Reactors, Auxiliary
equipment shall comply with
the
latest version of relevant
Indian Standards/International standards.
A. Capacitor banks:
The capacitor banks are for use in a 3 phase 50 Hz 11 KV
system. Capacitor bank shall consists of small units of
capacitor cells series/parallel combination per phase,
each with an out put rating of 100/150/200/400 kVAr, 7.3 KV
single phase. Capacitor units should be connected in
externally star with appropriate number of capacitors in
parallel as per requirement. For Example 3 single units of
150 KVAr connected in star to obtain 450 and 2 capacitors
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Technical specification
units in parallel per phase with 3 phase connection in star
to obtain 900 KVAr OR 3 single units of 100/200 KVAr
connected in star to obtain 300/600 and 2 capacitors units of
200 KVAr in parallel per phase with 3 phase connection in
star to obtain 1200 KVAR at 12.65 KV 3 phase. Necessary
number of steps should be provided to meet requirement
given in the schedule.
Table 1.0: Capacitor Bank Rating: Type - I
Sr. Transformer Capacitor
Bank Step configuration kVAr Combination of Output available (KVAr)
No.
Rating
at 12.89 450 XX 3No.
Units
I. Rating
5000 KVA
2250 KVAR
+ of
900
X 1 450, 900,1350,2250
kV
II 8000 KVA
2700 KVAR
450 X 2 + 900 X 2 450, 900, 1350, 2250, 2700
III 10000 KVA
3600 KVAR
900 X 4
900, 1800, 2700 & 3600
Each capacitor unit should be provided with external expulsion
fuse 12 KV class and suitable current rating. Capacitor shall
meet following specifications:
4. Temperature Category:
The capacitor shall be suitable for upper limit of temperature
category 50 Deg. C as per IS: 13925.
5.Rated Voltage:
The rated voltage of 3 phase capacitor banks shall be 12.65 KV
(phase to phase).
6.Rated Output:
The
rated
output
of
3
phase capacitor banks shall
2250/3600 kVAr at the maximum operational voltage of 12.65 KV
intended for use on power transformers ratings of 5MVA, 8 MVA,
10 MVA. The standard basic unit capacitors (single phase) shall be
100/150/200/400 kVAr. The unit connected in externally star
formation with floating neutral.
be
7. Permissible Overloads:
For capacitor covered
in this
specification,
the maximum
permissible overloads with regard to voltage, current and reactive
output shall not exceed the limits specified in IS:13925.
8. Power Loss:
The power loss in capacitors shall not exceed 0.2 watt / KVAR
(Subject to tolerance of + 10%).
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9. Discharge device:
Suitable discharge device shall be connected across the
capacitor unit in accordance with IS:13925. The discharge device
shall reduce the residual voltage from the crest value of the rated
voltage to 50 V the or less within 10 Minutes after the capacitor is
disconnected from the source supply.
10. Earthing Connections:
The container of each capacitor unit shall be provided with suitable
earthing terminal clearly marked with Earth symbol.
11. Protective Fuses :
The capacitor units shall be provided with external Expulsion fuses
together with fixing accessories.
12. General Requirements:
The capacitor shall be of non-PCB type, using polypropylene film
as the dielectric. Complete
mounting
brackets supporting
insulators and all other components for formation of capacitor
banks racks shall be supplied along with the capacitor units.
Necessary foundation bolts I nuts shall also be supplied. The outside
of the capacitor container and other structures should have
smooth and tidy look and should be coated with the weather
proof, corrosion-resistant paint of white or light grey.
13. Marking:
The capacitor unit shall be provided with a rating plate and
terminal markings as stipulated in IS: 13925. The bidder shall
submit the type test report along with the bid.
14. TESTS:
The switched capacitors shall be subjected to all the type, routine
and acceptance test in accordance with IS: 13925.
B AUTOMATIC CONTROL UNIT
15. Switching Arrangement:
1.1 The Automatic control unit shall be provided inside the
control;
room
to continuously monitor total load KVAR on
secondary side of the transformer and shall automatically switch
ON or switch OFF the capacitor banks through the operation of 12KV
Capacitor Switch in accordance with the parameter given in table
no.1. Overriding provision shall also be made for electrical
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Technical specification
switching ON or OFF of the capacitor switch by the operator from
the ACU control box.
16. Time Delay:
The switching ON operation will take place after period of 10
minutes. The switching OFF operation of relevant steps will be
instantaneous.
17. Controls:
The Automatic control unit shall instantly switch OFF the incomer
VCB of capacitor bank in the following contingencies occurring in any
of the phases.
a) Voltage increased by 10% above the rated voltage of 11 KV.
b) Power transformer current impedance (due to single phasing
and for any other reasons) between any of the two phases
exceeding 20% of the lowest.
c) Current increases in any capacitor unit by 30% above the rated
current (only the relevant capacitor switch will open).
Current between any of the two phases of the capacitor bank
differs more than 15% of the lowest current of the 3 phases (only
the relevant capacitor switch will open)
18. Monitoring Facility:
A suitable display should be provided to indicate the capacitor current in
each phases of the complete capacitor bank on the ACU panel
inside the control room by putting anlogic circular dial ammeter.
Indications shall also be provided to indicate ON & OFF status of
each capacitor bank.
19. Control Power:
The DC control voltage for operation of the ACU shall be taken
from substation battery. The required control voltage shall be
110 VDC/110 VAC /230 VAC.
20. Temperature Variation:
The control equipment and associate circuitry shall be suitable
for operation at an ambient temperature in the range of + 5
deg C to (+) 50 deg C.
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Technical specification
21. Protection of ACU:
Besides in-built protection against lines surges and transient
over voltages, suitable fuses/ MCB shall
be provided
for
protection against over current. The ACU shall remain fully
functional during and after line surges and transient over
voltages.
22. Control Unit Casing:
Except for the terminals, the ACU shall be enclosed
suitable casing so as to avoid ingress of dust.
in a
23. Scope
This specification covers 11 KV, 50 Hz, Outdoor type automatic
Capacitor Switch suitable for switching capacitor steps of
300/450/600/900 & maximum up to 1200 kVAr
24. APPLICABLE STANDARDS
Unless otherwise stipulated in this specification the Capacitor
Switch shall comply with the latest version of IS:9920 (AC
Switches for voltages above 1000 V).
25. RATED VOTAGE
The rated voltage for the Capacitor Switch shall be 12 KV.
This represents the highest system voltage corresponding to
the nominal system voltage of 11 KV.
26. RATED CURRENT
The standard rated normal current shall be
200A
27. RATED CAPACITIVE SWITCHING CURRENT
The rated capacitive switching current shall not be less than
50 A Note: The capability of the Capacitor Switch shall also
take into account the parallel switching of capacitor bank steps.
28. RATED SHORT TIME CURRENT
The rated short time symmetrical current for 1 second shall
be 10KA (rms AC. component).
29. RATED MAKING CURRENT
The rated making current shall be 2.5 times the rms value of
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Technical specification
the a.c. component of rated short time capacity.
30. BASIC IMPULSE LEVEL (BIL)
The rated basic impulse level of Capacitor Switch to earth as
also across the open terminals shall be 75 KV.
31. CONTROL SUPPLY
The control power for closing the Capacitor Switch shall be 230
V single phase AC supply. The closing mechanism shall be
suitable for a voltage variation of (+) 10% to (-)20%.
32. DESIGN & CONSTRUCTION REQUIREMENSTS
32.1.
TYPE
The Capacitor Switch shall be of either vacuum or SF6
type.
32.2.
The Capacitor Switch shall be of three
construction
and shall
be suitable for
operation.
phase
remote
32.3.
The Capacitor Switch shall be suitable for outdoor
installation and shall have sealed weather proof type
construction.
32.4.
The Capacitor Switch shall be provided with a
mechanical indicator to show whether the contact is
in open/closed position, locally, as also through
indication on the ACU panel.
32.5.
The metallic enclosure of the Capacitor Switch shall be
provided with two earthing terminals marked with the
earth symbol.
32.6
The bushings provided on the switch shall have clamp
type of terminals to directly
receive
aluminium
conductors up to 10mm dia in
both
horizontal
and vertical directions.
The terminal
arrangement
shall be such as to avoid bimetallic corrosion.
33.0PERATING MECHANSIM
The operating mechanism shall be either solenoid or motor
charged spring for which the control supply shall be as per
clause 31.
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Technical specification
34. MECHANICAL AND ELECTRICAL ENDURANCE
The Capacitor Switch shall be capable of performing not
less
than
10,000 mechanical operations and 10,000
electrical operations at 50A capacitive current without getting
damaged.
35.MARKING
The Capacitor Switch shall be provided with a legible and indelibly
marked name plate with the following:
a) Name of the manufacturer.
b) Type, designation and serial
number.
c) Rated voltage and current.
d)
Rated
frequency.
e)
Number
of
poles.
f)
Rated
short
time
current
(symmetrical).
g) Rated making current.
h) Rated capacitive switching current.
36. TESTS
The Capacitor Switch shall be subjected to the following tests in
accordance with the IS:9920 (Part-IV).
36.1.
a)
Type Tests
Tests to verify the insulation level, including withstand
tests at power frequency voltages on auxiliary equipment.
b) Tests to prove that the temperature rise of any part does
not exceed the specified values.
c) Making and breaking tests including tests for the rated
capacitive
current.
d) Tests to prove the capability of the switch to carry the
rated short time
current.
e)
Tests
to
prove
satisfactory
mechanical/electrical endurance.
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36.2. Routine
Tests
a) Power frequency voltage dry tests.
b) Voltage tests for auxiliary circuits.
c) Measurement of the resistance of the main
circuits.
d) Tests to prove satisfactory operation.
D. AUXILARY EQUIPMENTS
37. Isolator:
37.1.
The
Isolator
shall
be
Outdoor
type,
11
KV,
400/630/800Amp, Single throw, Double break, off load
type, triple pole, Horizontal gang operated with earth
switch.
37.2.
Tests: The Isolator shall be type tested and shall be
subjected to routine and acceptance test in
accordance with IS: 1818-1972.
37.3.
The
bidder
shall
submit
guaranteed
particulars along with their bid.
technical
38. 11 KV lndoor Vacuum Circuit Breaker with Panel:
1.0 Scope:
The specification covers supply and installation of 3 pole, 50Hz at
11 KV, 350 MVA rupturing capacity, 400/600/800 Amp r a t e d current.
V.C.B. shall comply the latest specification of APDCL. Vacuum circuit
breaker having motor operated spring changing mechanism and
electrical as well as manual closing facility for indoor installation
matching / in conjunction with existing 11 KV panels including all
necessary equipment such as CT(S) as per rating of capacitor
bank, PT(S) and instruments such as Ammeter, Voltmeter Kvar
and devices like relays as follows.
i)
ii)
T h r e e No of Voltmeter (0-15 KV), 3 Nos. Ammeter of size
(144 X144mm) of range 0-400/800Amp shall be fitted with
each panel. The meters shall be analogic with circular
dial.
Relays: NUMERICAL
a) Over Current = 2 Nos. + Earth Fault = 1 No combined one unit.
b) Over Voltage Protection
c) Unbalance Protection: Neutral displacement relay
d) No voltage / Under Voltage Protection with 600 sec. timer
e) Auxiliary relays to suit the purpose.
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Technical specification
1.1 Rating:
The VCB shall comply with the following requirements:
i) Nominal System Voltage: 11 KV.
ii ) Maximum System Voltage: 12KV.
iii) Rated Current: 400A/630A/800A.
v) Frequency: 50 Hz.
v) Insulation level: 28KV (rms) / 75KV (peak).
vi) Operating Mechanism: Spring Charged Motor.
vii) Auxiliary Voltage: 11OV DC& 240 VAC.
viii) Creepage Distance: 25 mm/KV
1.2 Tests: The Vacuum Circuit Breaker shall be type tested and
shall be
Subjected to routine and acceptance test in accordance with IS:
13118.
1.3 Guaranteed technical Particulars: The bidder shall submit guaranteedTechnical particulars along
with their bid.
39. Current Transformer:
1.0 The current transformers shall be dry type, suitable current
ratio and burden for measuring the capacitor current, shall
form part of the equipment to be supplied. These CT‘s shall
be form an either an integral part of Indoor VCB or may be
separate outdoor type on structure. The accuracy class
for the purpose of measuring the current shall be1.0.
1.1 Tests: The Current Transformer shall be type tested and
shall be subjected to routine and acceptance test in
accordance with IS: 2705.
1.2 The bidder shall submit guaranteed technical particulars
along with their bid.
40. Lightning Arrestor:
1.0 The specification covers the supply, delivery, erection,
testing & commissioning of 9 KV, 10 KA, Station class heavy duty,
gapless, metal (zinc) oxide surge arrestors complete along
with clamps, complete fitting and accessories for installation
on outdoor type 11 KV switchgear, transmission lines,
transformers etc.
1.1 Tests: The Lightning Arrestors shall be type tested and
shall
be subjected
to routine and acceptance test in
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Technical specification
accordance with IS: 3070.
1.2 The bidder shall submit guaranteed technical particulars
along with their bid.
41.0
Residual
Transformer:
Voltage
1.0 The Residual Voltage Transformer shall be oil cooled type, 11 KV
class, 5 Limb, with three windings i.e. Star/Star — Open delta. The
Primary winding-I in Star, Secondary-I in Star for metering and
Secondary-Il in Open delta for protection.
1.1 Tests: The residual Voltage Transformer shall be type tested
and shall be subjected to routine and acceptance test in
accordance with IS: 3156.
1.2 The bidder shall submit guaranteed technical particulars along
with their bid.
43. Expulsion Fuses:
1.0 Suitable outdoor type 11 KV expulsion fuses along with the
mounting insulators etc. to provide proper protection for the
capacitor unit shall form part of the equipment to be supplied.
44. Series Reactors:
1.0 0.2 % Series reactor per phase per step of capacitor rating
for inrush current restriction to be connected on neutral end as
per IS: 5553. The rated voltage shall be 12 KV. The reactor shall
be dry type single phase reactors mounted on post insulators and
designed to carry 130 % of rated current continuously without
exceeding the temperature rise & shall be applicable for thermal
class of insulation used. The reactor shall be mounted on
structure.
1.1 Tests: The series reactor shall be type tested and shall be
subjected to routine and acceptance test in accordance with IS:
5553.
1.2 The bidder shall submit guaranteed technical particulars
along with their bid.
45. 11 KV HT Cable (XLPE):
A Power Cable:
1.0 11 KV power cable shall be hot cured XLPE of following size
conforming to IS: 7098 (P-Il) amended latest.
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Technical specification
11 KV Incoming: Three/Single core, 95/125/240/400 Sq. MM.
11KV (E). Jointing kit shall be heat shrink type as per latest
relevant IS specification for indoor and out door utilization matching
with the above cables.
1.1 Cable Jointing: - Jointing should be heat shrink type. All
materials required for such type of jointing of XLPE cable shall be
supplied by the contractor. The work shall be carried out only by
licensed / experienced cable jointer holding necessary license of
cable jointing of appropriate grade. Sufficient surplus cable in the
form of loop shall be left on both sides of the cable.
B Control cable:
The control cable shall conform to IS: 1554 (Part-I) 1976. All control
cable shall be of copper and armored type. The bidder may furnish
cable such schedule after finalization of sub-station layout,
associated cable connection.
46. Capacitor Bank Structure :
Capacitor bank shall be outdoor type, each individual step along
with required current limiting reactors , capacitor switch, RVT
etc.. shall be mounted
on Suitable G.I. mounting and
elevating structure , each capacitor unit shall be provided with
an external expulsion fuses .
Bank shall be complete with necessary 11 KV class post insulator
,aluminium bus bar etc.
47.SUBMISSION AND APPROVAL OF
DRAWINGS:
Following drawings and technical documents shall be submitted
along with the bid.
• Technical data sheet
• GA drawings.
• Bill of Material.
 General Technical Particulars.
47.
INSTALLATION
MAINTAINANCE:
OPERATION
AND
The supplier shall provide:
1)
Necessary manual
on
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Technical specification
maintain ace as also the schedule for the routine testing or
check ups of all the equipments covered by the installation.
2) List of
recommended spares indicating prices and
specialized test equipments required for the routine testing of
the system.
48.GUIDANCEFOR PROCUREMENT:
The entire equipment covered under this specification shall be
covered as a single package to avoid the problem of
mismatching for maintenance etc.
49. WARRANTY:
The suppler shall guarantee satisfactory performance of
the complete capacitor bank installation for a period of 36
months from the date from the date of commissioning, which
ever is earlier. During the warranty period all repairs/replacements
shall be carried out free of cost.
50. INSPECTION:
All tests and inspection shall be made at the place of
manufacturer unless otherwise especially agreed upon by
manufacturer and the purchaser at the time of purchase.
manufacturer shall afford the
inspector representing
purchaser, all reasonable facilities, without charge, to satisfy
that the material being supplied is in accordance with
specification.
the
the
The
the
him
the
The purchaser has the right to get the tests carried out at
his own cost from an independent agency, whenever there is a
dispute regarding the quality of the supply.
The manufacturer shall be responsible to pay penalty of
Rs 20,000/- for each occasion at which the fake inspection call has
been made or the material is rejected during testing/inspection by
the authorized agency/representative of the Nigam. This penalty
would be in addition to the expenses incurred by the Company in
deputing the Inspecting Officer, carrying out such inspection
51. Challenge Clause:The material offered/received after the inspection by
the authorized ]officer may again be subjected to the test for or
any parameter from any testing house/in-house technique of the
Company & the results if found deviating un-acceptable or not
complying to approved GTP‘s the bidder shall arrange to supply
the replacement within thirty (30) days of such detection at his
cost including to & fro transportation. In addition,
penalty @10% of cost of the inspected lot of material shall be
imposed.
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TECHNICAL SPECIFICATIONS FOR LT ABC CONDUCTORS
CONNECTORS AND FITTINGS FOR LV – ABC
Standards: NF C 33020, 33021, 33040, 33041, 33042 & ESI 43-14
Summary:
1.
2.
3.
4.
5.
6.
7.
8.
9.
General conditions
Anchoring clamps
Suspension clamps
Service clamps
Transformer connections
Junctions
Insulation Piercing Connectors
Distribution boxes
Eye Hooks
1. General Conditions
The products shall be in accordance with Indian standards and most of the European recognised
standards used in LT ABC (NFC for example) or with any relevant standard.







Marking: Each product shall be clearly identified with Manufacturer name or
trade mark, reference and capacity of the item and batch No.
Packaging: Manufacturer shall mention the packaging of each item.
Installation instruction should be included in the packaging.
Type tests: Each supplier should provide type test reports with the offer,
carried out in accordance with one of the referenced standards in NABL
accredited laboratory.
Routine tests: Suppliers shall provide a control plan, which will be
implemented on each item. Routine Test reports should be submitted by the
manufacturer with the Inspection Call.
Quality: All suppliers should be ISO 9000 certified.
Anchoring and Suspension clamps should be installable on existing poles
using appropriate devices (hooks, pigtails, brackets etc.)
All crimped connectors should be installed with mechanical or hydraulic hand
crimping tools.
2. Anchoring clamp for Insulated messenger:
The clamps should be designed to anchor LV-AB Cable with insulated
neutral messenger. The clamp should consists of an Aluminium alloy
corrosion resistant castled body, bail of stainless steel and self-adjusting
plastic wedges which shall anchor/hold the neutral messenger without
damaging the insulation.
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Technical specification








The clamp should be installed properly.
No losable part in the process of clamping arrangement.
The clamp should conform to the standard NF C 33041 and 042 or
equivalent I.S., if any.
The clamp body should be made of corrosion resistant Aluminium
alloy, bail should be of stainless steel and wedges should be of
weather and UV resistant polymer.
Clamps should be fixed with pole by eye hook/bracket. Bracket should
be made of corrosion resistant Aluminium alloy.
Ultimate Tensile Strength of the clamp should not be less than 15 KN
for 50/70 Sq.mm insulated messenger wire / 10 KN for 25/35 sq.mm
insulated messenger wire.
Slip load of the clamp should not be less than 3 KN for 50/70 Sq.mm
insulated messenger wire/2 KN for 25/35 sq.mm insulated messenger
wire.
Design as per furnished drawing.
3. Suspension clamp for insulated neutral messenger:
The clamps should be designed to hang LV-AB Cables with insulated neutral
messengers. The neutral messengers should be fixed by an adjustable grip device.
A movable link should allow longitudinal and transversal movement of the clamp
body.










The clamp should be installed properly.
No losable part in the process of clamping arrangement.
The clamp should conform to the standard NF C 33040 or equivalent I.S.,
if any.
The clamp and the link made of the Polymer should provide an additional
insulation between the cable and the pole.
The clamps and the movable links should be made of weather and UV
resistant glass fibre reinforced polymer.
Clamps should be fixed with pole by eye hook/bracket. Bracket should be
made of corrosion resistant aluminium alloy.
Ultimate Tensile Strength of the clamp should not be less than 15 KN for
50/70 Sq.mm insulated messenger wire / 4.3 KN for 25/35 sq.mm
insulated messenger wire.
Maximum Allowable load of the clamp should not be less than 20 KN for
50/70 Sq.mm insulated messenger wire / 15 KN for 25/35 sq.mm insulated
messenger wire
The clamp should sustain to maximum angle of deviation of 60 degrees of
the conductors.
Design as per furnished drawing.
4. Service clamps
The clamps should be designed to anchor insulated service lines (armoured or
unarmoured) with 2/4 conductors.
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





The clamps should be made of weather and UV resistant polymer.
The clamp should be installed properly.
No losable part in the process of clamping arrangement.
The clamp should conform to the standard NF C 33042 or equivalent I.S.,
if any.
Breaking load of the clamp should not be less than 3 KN.
Design as per furnished drawing.
5. Transformer connections
 The connection to the transformer should be made with Pre-Insulated Lugs
for Phase and Street Lighting conductors and with an Aluminium Lug for
Neutral Messenger. If the Bus Bars are of Copper, the Lugs should be
preferably Bi-metallic type.
 The Barrel of the Lug normally insulated with an Anti-UV black
Thermoplastic tube sealed with a Flexible ring. Die reference, size and
strip length are indicated on the plastic.
 Sizes Covered: 16 – 70 & up to 150 mm² Aluminium XLPE insulated
 Referenced standard: NFC 33 021 or equivalent I.S., if any.
 Design as per furnished drawing.
.
6. Junction sleeves





The sleeves should be Pre - Insulated for Phases, neutral messengers and
Street Lighting conductors.
Sleeve should be made of Aluminium, insulated with an anti UV black
thermoplastic tube hermetically sealed two ends with 2 flexible rings. Die
reference, size and strip length are indicated on the sleeve itself.
Sizes needed: 16 – 70 -& upto150 mm² for Aluminium XLPE insulated
Referenced standard: NFC 33 021 or equivalent I.S., if any.
Design as per furnished drawing.
7. Insulation Piercing Connectors as per the standard NF C 33020 or equivalent
I.S., if any.
Scope
In the process of replacing the Bare Conductors with LT AB Cables
to reduce power theft & Transmission Losses, it is important to
analyze the proper method of providing service connection from AB
Cables to our consumers without damaging the cable. Removal of
Bare Conductor, Stringing of LT AB Cable & re-establishing the
service connections should be simultaneous process. In this regard
the Insulating Piercing Connectors are required- a) for providing 1-2
service connections from 8 mtr. PCC LT pole, b) for providing supply
to Junction/ Distribution Box from AB Cable & c) for establishing Tee
connection from LT ABC to LT ABC.
This Insulating Piercing Connectors should not be exposed to any
bare conductor in the environment during connection. The
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Technical specification
connectors should be totally Weather & Moisture proof so that no
water or moisture can enter through the pierced holes on to the
cable insulation.
It must have Shear Head type mechanism to control the effective
Torque during connection and to ensure perfect installation.
Connectors should not have any losable parts, which may drop and
then lost while installation at overhead conditions. For individual
connectors Torque required for different conductor sizes should be
mentioned in the equipment.
Technical
requisites
Construction:
Voltage
Ratings:
Moisture
Ingress:
Working
Temp.:
Materials:
The connectors should be totally insulated with no loose parts. The
connectors should be totally Weather & Moisture proof so that no
water or moisture can enter through the pierced holes on the cable
insulation.
The maximum voltage withstand capacity should be 6 KV.
The connectors should work at 30 cm under water bath for 30 min. &
voltage applied of 6KV for 1 min. without any flashover/ failure &
moisture ingress in it.
Designed for installation from -10˚C upto +60˚C & operation
experience with temperature from -20˚C upto +75˚C.
Material used in the manufacturing process of the components of
this product should be specified in the respective product drawings &
can be summarized as follows:
 All the metallic part of the connector should be Corrosion
resistance & should be proven in Salt Fog chamber & Wet
SO2 gas chamber & there should not be any change in
contact resistance & temperature after overloads & load
cycling.
 The contact plates should be made of tinned Copper.
 Connector teeth should be factory greased & sealed to retard
water or moisture ingress & corrosion.
 The insulation material should be made of weather & UV
resistance, reinforced polymer.
 The outer metallic part should have potential free tightening
bolts to allow safe installation on life lines.
 The bolts should be of Shear Head type so that it controls the
effective applied Torque during installation & break off at a
specified torque after establishing proper connection.
 The connector should not have any losable component. The
cable end cap should be attached to the body.
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Technical specification
Testing
Standards:
The Insulating Piercing Connector should conform to following std.Tests
Tests Standard/ Test Procedure
Corrosion
As per NF C 33-020 (Jun‘98), or equivalent I.S.,
Qualification
if any.
Test
Exposure in Saline Environment- The exposure
should be carried out as per NF EN 60068-211(Aug‘99) std. requirement. The concentration
of Saline solution must be of 5% ± 1% in mass,
& the temperature of the test chamber must be
maintained at 35˚C ± 2˚C.
Exposure in Sulphur environment saturated of
humidity - The exposure should be carried out
as per NF T 30-055(Mar‘74) std. requirement.
SO2 concentration in the chamber should be
0.067% in volume. The temperature of the test
chamber should be increased to 40˚C ± 3˚C.
The total test should include four identical
periods of 14 days, in which 7 days of exposure
in Saline environment & in other 7 days - 8 hrs
cycles in SO2 environment & 16 hrs in
laboratory environment.
Electrical
As per NF C 33-020 & NF C 33-004 (Jun‘98), or
Ageing Test
equivalent I.S., if any.
Total no. of cycles-200, Heating time -60 mins.,
Cooling time- 45mins., Pause time – 2 mins.
Dielectric
As per NF C 33-020 (Jun‘98), or equivalent I.S.,
Investigation
if any.
Test in Water
The connector should be placed in an ambient
temperature between 15˚C & 30˚C & relative
humidity between 25% & 75%. The tightening of
the connectors should be at minimal value of the
torque indicated by the manufacturer. The
sample should be placed in tank full of water on
30cm height, after an immersion length of
30mins. The set is subjected to a dielectric test
under a voltage of 6KV at industrial frequency
during 1 min. No flashover/ breakdown should
occur at 6KV during 1 min.
Mechanical
Tests
As per NF C 33-020 (Jun‘98), or equivalent I.S.,
if any.
For checking electrical continuity, shear heads &
mechanical behaviour of the connector‘s
suitable tests as per the above specification
have to conduct.
Referenced standard: NFC 33 020 or equivalent I.S., if any.
8. ABC Service main Distribution boxes
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Technical specification
Scope
Technical
requisites
Construction:
Current
Ratings:
Voltage
Ratings:
Working
Temp.:
Materials:
This Distribution Box should be Weather & Moisture Proof with
Spring loaded Bus Bar system & should be able to carry a current
according to specified ampacity. It can have 1 /3-phase input &
provision for 4 or 9 nos. of 3- phase or 1-phase outputs. The box
should have the provision for special key for locking & Proper
arrangement of sealing. The boxes should be assembled on the
pole using Metal Tapes & Buckles or Bolts.
No. of Boxes
per pole may vary with supporting arrangement for more no. of
service connections.
Distribution Boxes should be designed with Bus Bars with spring
action contact, so that no screw-bolt technique is required to
operate & only insertion of the conductor into the specified groove
of the Busbar is sufficient for proper connection. It should be used
for multiple connections (3-phase or 1-phase) in low voltage
Distribution Network.
The boxes should be suitable for 1/ 3-phase (4 cores) inputs &
provision for 4 or 9 nos. of 3- phase or 1-phase outputs. Bus bars
should be with a continuous pair of contact bars with colour code to
facilitate the identification of the correct energy phase.
The box should be able to incorporate the input or output cable dia.
of maximum 16mm. (Equivalent to 120Sqmm.)
The Boxes should consist of special type Lock & key system as
well as provision for sealing for complete protection of the service
connection contacts.
The maximum current rating should be 140A/ 200A/ 250A. &
concerned authority should have the liberty to choose among the
above ratings as per their requirement.
The maximum voltage withstand capacity should be 600V.
Safe working temperature should be around 80˚C for Outer Box &
100˚C for metallic Bus bars.
Material used in the manufacturing process of the components of
this product should be specified in the respective product drawings
& can be summarized as follows:
 Outer Box (Base & Cap): With UV protection & Flame
retardant characteristics (HB, as per UL 94- Tests for
Flammability of Plastic materials) & preferably made up of
ASA (Acrylonitrile Styrene Acrylate).
 Cable Grommets: Ethylene-Propylene Rubber.
 Safety Key: PA 6.6 (Nylon).
 Safety Screw: Stainless Steel or Plating Finished steel.
 Insulator protection as per IP 44
 Bus bars or Terminal Blocks: PA 6.6 (Nylon), Stainless Steel
& Copper.
 Button & Cable Holder: PA 6.6 (Nylon) with 50% Glass
Fibre.
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Technical specification
Locking
System:
 Busbar Insulation: Polyamide.
The boxes should consist of Special type Lock & Key arrangement
as well as provision for sealing for complete protection of the
service connection contacts.
Testing Impact Resistance should be according to UL 746C. Insulation Protection should
Standa be as per IP 44. The Outer Plastic box should conform to following std.rds:
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Technical specification
9.
Eye Hooks:
Eye hooks should be designed as to hold Suspension Clamps and Dead end
Clamps and to be installed with the Pole Clamps: Eye hooks should be made of forged Galvanised Steel.




The clamps corrosion resistance should confirm to the standard IS: 2629 and IS:
2633
Bolt and nuts should be made of hot dip galvanised steel, according to VDE 0210
and VDE 0212.
Ultimate Tensile Strength (UTS) of the clamp should be 20 KN.
Design as per furnished drawing.
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Technical specification
TECHNICAL DATASHEETS
GUARANTEED TECHNICAL PARTICULARS for premoulded Straight joint FOR LT
1.1kv
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
17.
18.
19.
Name & address of the
Manufacturer
Applicable standard
Type of Cable jointing kit
Application
Nominal system voltage (kV)
Maximum system voltage (kV)
Number of cores
Type of insulation
Type of screening
System Neutral Earthing
Maximum performance
AC voltage
Load cycling 900C + 50C (no. of
cycles)
Impulse voltage
Partial discharge voltage
Thermal short circuit
DC voltage
Dynamic short circuit
Authorised Signatory
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Technical specification
Guaranteed Technical Particulars for Insulating Piercing Connectors
Type
1.
2.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
For
Street
Light
For DB Charging
For ABC to
ABC TEE
Name of the Manufacturer
Is manufacturer of
accessories as ISO 9001 2000 company
a) Copies of Certificate
Enclosed
b) Are GA Drawing
enclosed
Applicable standard
Type of connectors
Application
Is any metallic part carrying
potential in operation
exposed during installation
Are end caps of branch cable
a) Slide on type
b) Rigid
Are torque limiting shear
heads provided to tightening
bolts
Range of cable sizes
accommodated for main &
branch
Min. & Max. torque defined
Torque for establishing
connection between main
and branch
Max. tensile load for no
breakdown of main
conductor (for each crosssection)
Max. tensile load on branch
conductor for no break /
slippage
Voltage withstand under
water emersion
Is electrical Ageing test
report enclosed
No. of Cycles
Max. temp at each cycle
Marking and embossing on
the connector
Authorised Signatory
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Technical specification
Guaranteed Technical Particulars for Eye Hook
Sl No Particulars
Unit
1
Type of Clamp
2
Name of the Manufacturer
3
Place of Manufacture
4
Type of design
5
7
Type & grade Metallic / Nonmetallic
material
Type of hot dip galvanizing & thickness
of Zinc coating
Dimensions
mm
8
Approximate weight
Kg
9
Ultimate tensile strength
KN
6
Bidder‘s Offer
Authorised Signatory
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Technical specification
Guaranteed Technical Particulars for Suspension Clamps suitable for
Insulated Messenger wire
Sl Particulars
No
1 Type of Clamp
2
4
Name
of
the
Manufacturer
Place
of
Manufacture
Type of design
5
Standard
6
Loop
anchor
attachment
(Open/Close)
Installation
(with/without
disassembly)
Type
&
grade
Metallic
/
Nonmetallic
material
Marking
3
7
8
9
Unit
10 Colour
of
Nonmetallic parts
11 Dimensions
Mm
12 Approximate weight
Kg
Bidder‘s offer
Bidder‘s offer
13 Ultimate
tensile
KN
strength
14 Maximum allowable
KN
load
15 Maximum angle of Degrees
deviation
of
conductors
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Technical specification
Guaranteed Technical Particulars for Dead end Clamps suitable for Insulated
Messenger wire
Sl
No
1
2
Particulars
Bidder‘s Offer
Bidder‘s Offer
Type of Clamp
3
Name
of
the
Manufacturer
Place of Manufacture
4
Range of conductor size
5
Standard
6
Type of design
7
Installation (with/without
disassembly)
Type & grade Metallic /
Nonmetallic material
8
Unit
Sq
mm
9
Marking
10
11
Colour of Nonmetallic
parts
Dimensions
Mm
12
Approximate weight
Kg
13
Ultimate tensile strength
KN
14
Maximum allowable load
KN
15
Slip load
KN
Authorised Signatory
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Technical specification
GUARANTEED TECHNICAL PARTICULARS for Waterproof preinsulated
compression type bimetallic socket FOR LT 1.1kv
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
17.
18.
19.
Name & address of the
Manufacturer
Applicable standard
Type of Cable jointing kit
Application
Nominal system voltage (kV)
Maximum system voltage (kV)
Number of cores
Type of insulation
Type of screening
System Neutral Earthing
Maximum performance
AC voltage
Load cycling 900C + 50C (no. of
cycles)
Impulse voltage
Partial discharge voltage
Thermal short circuit
DC voltage
Dynamic short circuit
Authorised Signatory
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Technical specification
GUARANTEED TECHNICAL PARTICULARS (GTP) FOR SPRING LOADED
CONSTANT PREASSURE MULTI CONNECTION ASA DISTRIBUTION SYSTEM
Bidder‘s offer
Sl No Particulars
1
Name of the Manufacturer
2
Place of Manufacture
3
Type of Box
4
Type of design
Application
5
6
Installation
7
8
9
Type & grade Metallic / Nonmetallic
materials for Inner Contact Region
Type of material for Outer Box
Maximum Current Ratings
10
Maximum Voltage withstand capacity
11
Safe Working Temperature
12
Insulation Protection
13
Impact Resistance
14
16
Range of cable sizes can be
accommodated
Are special keys Available for theft
protection
Provision for Lead sealing
17
Marking
18
Colour of Non metallic parts
19
Dimensions
15
Authorised Signatory
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Technical specification
TECHNICAL SPECIFICATIONS FOR ACCESSORIES AND
HARDWARE FITTINGS FOR HT – ABC
Summary:
10. General conditions
11. Tee Connections with Surge protection .
12. Straight Through Joints.
13. Outdoor End Terminations.
14. C-wedge boltless connector
15. Anchoring clamps
16. Suspension clamps
17. Eye Hooks.
18. Pole Clamps.
General Conditions
The products shall be in accordance with Indian standards and most of the European recognised
standards used in HT ABC with any relevant standard.

Marking: Each product shall be clearly identified with Manufacturer name or
trade mark, reference and capacity of the item and batch No.
 Packaging: Manufacturer shall mention the packaging of each item.
Installation instruction should be included in the packaging.
 Type tests: Each supplier should provide type test reports with the offer,
carried out in accordance with one of the referenced standards in NABL
accredited laboratory.
 Routine tests: Suppliers shall provide a control plan, which will be
implemented on each item. Routine Test reports should be submitted by the
manufacturer with the Inspection Call.
 Quality: All suppliers should be ISO 9000 certified.
 Anchoring and Suspension clamps should be installable on existing poles
using appropriate devices (hooks, Pole clamps etc.)
All crimped connectors should be installed with mechanical or hydraulic hand
crimping tools.
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Technical specification
Specification of Tee Connection with Insulated Busbar & Surge Protection for
11kv AB Cable
Scope
In the process of drawing HT 11KV AB cable, in between
Distribution Transformers has to be charged by the help of Tee
off. While charging the Distribution Transformer it has to be noted
that the main power cable is not discontinued. In this regard Tee
connection with Insulated Bus bar application with suitable
Aluminium Busbars, Insulating Heat shrinkable bus bar tubings,
Polymeric Insulators for Busbar fixing & Polymeric Surge Arrester
for Surge/ Lightning protection are used properly. The service
may be taken from the Tee connector with the help of AAC bare/
Insulated conductor to the Distribution Transformer.
Technical requisites
Busbars
Insulation:
Insulator:
Surge
Protection:
Suitable Aluminium rectangular Busbars of dimension 1m X
50mm X 6mm with provision for connecting two nos. of Cable end
terminations at both ends & tap off point at the centre of the
busbar. The Edges of the busbars should be free from any sharp
edges/ nicks.
The Bus bars should be fully insulated with Heat shrinkable
busbar tubings to prevent any bird fault or accidental contact.
Suitable polymeric pin type insulators should be used for fixing
Busbars on the Pole structure. The housing of the Insulators
should be made up of polymeric materials preferably Track
resistant EVA materials & should conform the following properties:
Mechanical Properties [kN]
Specified Cantilever Load
12.5
Maximum Design Cantilever Load 5.5
Specified Tension Load
25
Routine Test Load
12.5
Electrical Properties [kV]
AC Wet Withstand Voltage 61
AC Dry Withstand Voltage 95
AC Wet Flashover Voltage 72
AC Dry Flashover Voltage 104
Impulse Withstand Voltage 137
A metal oxide surge arrester with a housing made of polymeric
material preferably Silicone rubber, without air voids neither
between the housing and the metal-oxide resistors nor the
housing itself. Arresters must have directly moulded housings.
The arresters should be tested as per IEC 60099-4 & conform to
the following criteria:
Rated Voltage : 9KV
Nominal Discharge Current : 5KA
Distribution Class
Creepage length : >300mm.
Impulse Voltage 1.2/ 50µsec : 95KV
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Technical specification
Power frequency withstand voltage : 38KV
Voltage Ratings: Nominal system voltage (kV) : 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum system voltage (kV): 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum performance : For 11KV (E)
QUALITY ASSURANCE
The manufacturer shall be certified in accordance with ISO 9001. The supplier has
to provide a copy of a valid certificate along with his quote.
Relevant Manuals or Drawings shall be presented upon request to customer/utility.
PACKING AND SHIPMENT
Tee Jointing Kits shall be securely packed, complete with all accessories, in strong
non-returnable boxes, in such a manner as to prevent damage during shipment.
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Technical specification
Specification of Straight Through Joint for 11kv AB Cable
Scope
Technical
requisites
Conductor
Connection:
Void filling &
Stress Control:
Insulation Build
up & Insulation
screen:
Screen
Continuity:
Environmental
sealing
Voltage Ratings:
testing
Standards:
In the process of drawing HT 11Kv AB cable, at the end of one
drum of cable, to continue the drawing of the cable the cable from
other drum has to be joined by Midspan Inline Straight through
joints. In this regard, Straight through joint should be supplied with
suitable Mechanical Connector, proper Stress Control, adequate
Insulation, suitable screen continuity & sufficient environmental
sealing should be achieved.
Suitable Shear bolt type Al. Mechanical Connector has to be
used.
Suitable void filling Mastic & Heat shrinkable Stress control tube.
By Heat shrinkable dual wall tube with extruded Insulation &
semiconducting layers.
With the help of Copper wire mesh..
Outer sealing should be with the help of Heat Shrinkable outer
tube & with Proper sealing mastics.
Nominal system voltage (kV) : 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum system voltage (kV): 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum performance : For 11KV (E)
The Straight Through Joint should conform/ withstood the
following test std.Tests
Recommended Test values
AC High voltage
Load cycling 900C + 50C (no.
of cycles)
Load cycling 900C + 50C (no.
of cycles) under 0.25 mtr. of
water
Impulse voltage
Partial discharge voltage
Thermal short circuit
DC voltage
28.5KV (rms)
18 Cycles
12 Cycles
95KV (peak)
At 12.75KV < 5 pc
For 1 sec. KA will depend on
conductor size.
38KV for 15 mins.
QUALITY ASSURANCE
The manufacturer shall be certified in accordance with ISO 9001. The supplier has
to provide a copy of a valid certificate along with his quote.
Relevant Manuals or Drawings shall be presented upon request to customer/utility.
PACKING AND SHIPMENT
Straight through Jointing Kits shall be securely packed, complete with all
accessories, in strong non-returnable boxes, in such a manner as to prevent damage
during shipment.
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Technical specification
Specification of Outdoor End Termination for 11kv AB Cable
Scope
Technical
requisites
Conductor
Connection:
Void filling
Stress Control,
Environmental
Sealing & Anti
tracking
Earthing
Connection
Continuity:
Voltage Ratings:
testing
Standards:
In the process of drawing HT 11Kv AB cable, at the end of the
cabling system the cable has to be connected with the
Transformer end or with the bare overhead line by Outdoor end
terminations. In this regard, Outdoor end terminations should be
supplied with suitable Crimping type lugs, proper Stress Control,
adequate Insulation & sufficient environmental sealing should be
achieved.
Suitable Crimping type Al. lugs has to be used.
Suitable void filling Mastic.
By Heat shrinkable dual wall single tube has to be used for both
stress controlling & Environmental sealing purpose. Minimum
(one) no. of Heat shrinkable Rain shed can be used for increasing
Creepage distance.
With the help of Tinned Copper braid.
Nominal system voltage (kV) : 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum system voltage (kV): 6.6KV(UE)/11KV (E) (phase to
phase)
Maximum performance : For 11KV (E)
The Outdoor End Termination should conform/ withstood the
following test std.Tests
Recommended Test values
AC High voltage
Load cycling 900C + 50C (no.
of cycles)
Load cycling 900C + 50C (no.
of cycles) under 0.25 mtr. of
water
Impulse voltage
Partial discharge voltage
Thermal short circuit
DC voltage
28.5KV (rms)
18 Cycles
12 Cycles
95KV (peak)
At 12.75KV < 5 pc
For 1 sec. KA will depend on
conductor size.
38KV for 15 mins.
QUALITY ASSURANCE
The manufacturer shall be certified in accordance with ISO 9001. The supplier has
to provide a copy of a valid certificate along with his quote.
Relevant Manuals or Drawings shall be presented upon request to customer/utility.
PACKING AND SHIPMENT
Outdoor End Termination Kits shall be securely packed, complete with all
accessories, in strong non-returnable boxes, in such a manner as to prevent damage
during shipment.
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Technical specification
Specification of C Wedge Boltless connectors
Scope
Technical
requisites
The C-Type fired wedge boltless connectors shall be of high
strength and high
conductivity Aluminium alloy. The same shall be suitable for
use on all combinations of
Aluminium to Aluminium, or Aluminium to Copper conductors.
The components shall be properly proportioned to minimize
stress concentration, corrosion and deterioration by galvanic
action & should be used for taking tap off in AB Cable from
Bare overhead line. Bolted connectors should be avoided.
“C” TYPE FIRED WEDGE BOLT LESS CONNECTOR:
The connector consists of tapered ―C‖ shaped member and
wedge that made of Aluminium alloy.
The connector should be bolt less and Fired wedge system.
The ―C‖ member should be provided built-in spring tension to
maintain constant pressure for a firm electrical contact.
The connector shall be used for multiple combinations of
solid/stranded AAC, AAAC, ACSR, copper combination etc.
Copper to Copper connectors the ―C‖ member is composed of
Aluminum Bronze alloy and the wedge of Copper alloy very
close to pure copper.
―C‖ member wedge shall be factory coated with an inhibitor
containing abrasive particles to help clean and contact surfaces
during installation.
The C-Type fired wedge boltless connectors shall conform to
the latest editions of ANSI C 119.4 - 2004 Standards.
The wedge type boltless connectors shall consists of CMember and wedge. The wedge shall be inserted at a speed of
40 m./Sec approx so as to be effective in abrading all sliding
surface and disrupting surface oxide film to generate large
number of contact spot in the electrical interfaces. The
mechanical stresses during the wedge insertion shall cause
elastic deformation of the C-Clamp and shall increase the
geometrical conformation of the clamp to the conductor. An
Oxidation inhibitor shall be applied to the surface thereby
elimination of oxidation of metallic surface. The normal current
carrying capacity of clamp shall not be less than the specified
in the specification. If the connectors are to be installed by
Powder actuated tool using cartridges with explosive, valid
explosive license issued by the Government of India/State
Government should be possessed.
Clamps shall be corona free and shall carry an overload of at
least 20% over the rated current. The connectors should be
easily removable and reusable type. Reusable means that the
connector may be removed from service and installed again.
Prior to reuse, any instructions to be followed for reconditioning
the reusable connector shall be furnished.
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Technical specification
QUALITY ASSURANCE
The manufacturer shall be certified in accordance with ISO 9001. The supplier has
to provide a copy of a valid certificate along with his quote.
Relevant Manuals or Drawings shall be presented upon request to customer/utility.
PACKING AND SHIPMENT
Outdoor End Termination Kits shall be securely packed, complete with all
accessories, in strong non-returnable boxes, in such a manner as to prevent damage
during shipment.
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Technical specification
Anchoring Clamp for Bare messenger:
The clamps should be designed to anchor HT-AB Cable with Bare neutral
messenger. The clamp should consists of an Aluminium alloy corrosion
resistant casted body and 3 U bolts which shall anchor/hold the neutral
messenger without damaging the conductor strands.








The clamp should be installed properly.
No losable part in the process of clamping arrangement.
The clamp should conform to the standard IS 2629 & 2633.
The clamp body should be made of Galvanised Steel to the standard
IS 2629 & 2633 & wedges should be made of corrosion resistant
Aluminium alloy as per IS 617- 1975.
Clamps should be fixed with pole by Eye hooks.
Ultimate Tensile Strength of the clamp should not be less than 20 KN.
Maximum Allowable load of the clamp should not be less than 20 KN.
Design as per furnished drawing.
Suspension clamp for Bare neutral messenger:
The clamps should be designed to hang HT-AB Cables with bare neutral
messengers. The neutral messengers should be fixed by an adjustable grip device
with 2 U bolts.
 The clamp should be installed properly.
 No losable part in the process of clamping arrangement.
 The clamp should conform to the standard IS 2629 & 2633 & REC Constr.
Standard E-34.
 The clamp body should be made of Galvanised Steel to the standard IS
2629 & 2633 & wedges should be made of corrosion resistant Aluminium
alloy as per IS 617- 1975.
 Clamps should be fixed with pole by Eye hook.
 Ultimate Tensile Strength of the clamp should not be less than 20 KN.
 Maximum Allowable load of the clamp should not be less than 20 KN.
 The clamp should sustain to maximum angle of deviation of 60 degrees of
the conductors.
 Design as per furnished drawing.
Eye Hooks:
Eye hooks should be designed as to hold Suspension Clamps and Dead end
Clamps on the poles: Eye hooks should be made of forged Galvanised Steel.




The clamps should be corrosion resistance & should confirm to the standard IS: 2629
and IS: 2633
Bolt and nuts should be made of hot dip galvanised steel, according to VDE 0210
and VDE 0212.
Ultimate Tensile Strength (UTS) of the clamp should be 15 KN.
Design as per furnished drawing.
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Technical specification
Pole Clamps:
Pole Clamps should be designed as to hold Eye hooks by two nut bolts on the
poles: Pole Clamps should be made of forged Galvanised Steel.




The clamps should be corrosion resistance & should confirm to the standard IS:
2629 and IS: 2633
Bolt and nuts should be made of hot dip galvanised steel, according to VDE 0210
and VDE 0212.
It can be fabricated from 50 x 6 mm GI flat.
Design as per furnished drawing.
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Technical specification
Technical Data schedule:
A. GUARANTEED TECHNICAL PARTICULARS FOR SUSPENSION CLAMP FOR
BARE MESSENGER WIRE
Sl.No
Description
1.
2.
3.
4.
5.
6.
Name & address of the Manufacturer
Applicable standard
Type of Clamp
Type of design
Voltage Grade (kV)
Loop anchor attachment
(open/close)
Installation (with/without disassembly)
Type & grade (metallic / non-metallic
material)
Type of hot dip galvanizing &
thickness of Zinc coating
Marking
Colour of non-metallic parts
Dimensions
Approximate weight
Ultimate tensile strength (KN)
Maximum allowable load (KN)
Max. angle of deviation of conductor
(degrees)
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Guaranteed particulars
Authorised Signatory
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Technical specification
B. GUARANTEED TECHNICAL PARTICULARS FOR DEAD END CLAMP FOR BARE
MESSENGER WIRE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Name & address of the
Manufacturer
Applicable standard
Type of Clamp
Type of design
Voltage Grade (Kv)
Loop anchor attachment
(open/close)
Installation (with/without disassembly)
Type & grade (metallic / nonmetallic material)
Type of hot dip galvanizing &
thickness of Zinc coating
Marking
Colour of non-metallic parts
Dimensions
Approximate weight
Ultimate tensile strength (KN)
Maximum allowable load (KN)
Authorised Signatory
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Technical specification
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
C. GUARANTEED TECHNICAL PARTICULARS FOR END TERMINATION KIT
Name & address of the Manufacturer
Applicable standard
Type of Cable jointing kit
Application
Nominal system voltage (kV)
Maximum system voltage (kV)
Number of main core
Number of branch conductor
Whether single tube is used for Stress
control & anti-tracking
Type of insulation
Type of screening
System neutral earthing
Maximum performance
AC voltage
Load cycling 900C + 50C (no. of cycles)
Load cycling 900C + 50C (no. of cycles)
under 0.25 mtr. of water
Impulse voltage
Partial discharge voltage
Thermal short circuit
DC voltage
Dynamic short circuit
Authorised Signatory
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Technical specification
D. GUARANTEED TECHNICAL PARTICULARS FOR STRAIGHT JOINT FOR HT 11KV (E)
Name & address of the
Manufacturer
2.
Applicable standard
3.
Type of Cable jointing kit
4.
Application
5.
Nominal system voltage (kV)
6.
Maximum system voltage (kV)
7.
Number of cores
8.
Type of insulation
9.
Type of screening
10.
System Neutral Earthing
11.
Maximum performance
12.
AC voltage
13.
Load cycling 900C + 50C (no. of
cycles)
14.
Load cycling 900C + 50C (no. of
cycles) under 0.25 mtr. of water
15.
Impulse voltage
16.
Partial discharge voltage
17.
Thermal short circuit
18.
DC voltage
19.
Dynamic short circuit
1.
Authorised Signatory
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Technical specification
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
E. GUARANTEED TECHNICAL PARTICULARS FOR TEE CONNECTION WITH SURGE
PROTECTION
Name & address of the Manufacturer
Applicable standard
Application
Nominal system voltage (kV)
Maximum system voltage (kV)
Number of main core
Number of branch conductor
Type of Busbar
Type of insulation
Type of Insulators
Cantilever Load of Insulator
Max. Design Cantilever load of
Insulator
Creepage Length of Insulator
Specified Tension Load of Insulator
AC Wet withstand voltage of Insulator
AC Dry withstand voltage of Insulator
AC Wet Flashover voltage of Insulator
AC Dry Flashover voltage of Insulator
Impulse withstand voltage of Insulator
Type of Surge arresters
Rated voltage of SA
Nominal Discharge Current of SA
Distribution Class of SA
Creepage Length of SA
Impulse Voltage of SA
Power frequency withstand Voltage of
SA
Authorised Signatory
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Technical specification
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
F. GUARANTEED TECHNICAL PARTICULARS FOR EYE HOOK
Name & address of the
Manufacturer
Applicable standard
Type of Clamp
Type of design
Type & grade (metallic / nonmetallic material)
Type of hot dip galvanizing &
thickness of Zinc coating
Marking
Colour of non-metallic parts
Dimensions
Approximate weight
Ultimate tensile strength (KN)
Authorised Signatory
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Technical specification
G. GUARANTEED TECHNICAL PARTICULARS FOR C FIRE WEDGE CLAMP
No
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Feature/Technical Details
Manufacturer‘s Name
Manufacturer‘s Location
Brand Name
Part Number
Application
Installation and Application Tooling
Connector Removal
Installation on Energized Lines
Conductor Size
Connector, Metallic Material
Connector, Non-Metallic Material
Voltage/Ampacity
Operating Temperature
Marking
Industry Standards
Overall Size
Authorised Signatory
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Technical specification
TECHNICAL SPECIFICATION OF 3-Ф Distribution Transformers of
11kV/433-250V, 16, 25, 63, 100 and 200KVA
SCOPE
1.1
This section of the specifications is intended to cover requirements for design,
engineering, manufacture, testing/inspection at manufacturer‘ works before
despatch, forwarding, packing, transporting and delivery at site of outdoor
type naturally air-cooled, 11kV/433-350V Distribution Transformers of
capacities 16, 25, 63,
100 and 200 KVA
complete with all
accessories/fittings, LV side protection and spare parts. The bidder shall
quote the price of transformer complete with first filling of oil.
2.0
2.1
BIDDING
Each Technical Proposal must be accompanied by each of the following
information/ documents with sufficient details along with other documents and
information mentioned elsewhere to enable the purchaser to make an
appraisal of the quality and suitability of the material and equipment offered.
(a)
Type test certificates of equipment of similar design from a nationally
recognised laboratory, preferably at CPRI/ERDA laboratory. The Type test
certificates should not be more than 3 (three) years old. The type rest
certificates should also be accompanied by the drawings of equipment tested
so that the test certificates can be directly linked to the equipments offered. In
this regard following points shall also be noted:
Equipment which has never been tested for critical performance
shall not be accepted. In such cases, a promise or agreement by a
bidder to have the equipment tested after award of a contract is
not acceptable.
(b)
(c)
(d)
Test reports to be acceptable must be related directly to the equipment
offered. Test reports for a higher class/rating of equipment are
acceptable with a commitment from bidder that the type test will be
performed free of charge on the particular equipment after the award of
contract.
Guaranteed and Other Particulars in the formats given in Schedule - A at the
end of this Section. The bid should also be accompanied by manufacturer‘s
literatures and brochures.
The bidder shall have to submit the Annexure-A as a first page of the
technical offer.
2.2
Failure to meet the requirement of this Clause 2.0 shall render a Bid nonresponsive.
3.0
3.1
STANDARDS
The Transformer and associated accessories shall conform to the latest
issues of the standards as given below, except to the extent explicitly modified
in this specification.
(1) CBIP manual on Transformers.
Publication no 275
(2) CEA Guidelines for Specification of Energy Efficient Outdoor Type
three phase and single phase Distribution Transformers, 2008.
(3) Power Transformers
IS:2026, IEC 76
(4) Outdoor distribution Transformer up to and including 100 kVAIS: 1180
(5) Insulating oils for transformers and switchgears
IS:335
(6) Bushings for alternating voltages above 1000 V
IS:2099
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Technical specification
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
3.2
4.0
4.1
Creepage distance (mm)
IS: 3347
Outdoor Bushings
IS:3347, DIN 42531 to 33
Specification for low voltage bushings
IS:7421
Dimensions for clamping arrangements for bushings
IS:4257
Specification for Al Wire rods
IS: 5434, ASTM B-233
Specification for Insulating Kraft Paper
IS:9335, IEC 554
Specification for Insulating Press Board
IS:1576, IEC 641
Code of practice for installation and maintenance
IS:10028
of transformers
(15) Guide for loading of oil immersed transformers
IS:6600
(16) Paper covered Aluminium conductor
IS:6162
(17) Rectangular Electrical conductor for electrical machine
IS:6160
(18) Electrical Power connector
IS: 5561
(19) Colours for ready mix paints.
IS: 5
(20) Ready mixed paint, brushing zinc chromate, priming
IS 104
(21) Specification for Copper wire rod
IS 12444, ASTM B-49
(22) Testing for steel sheets and strips and magnetic circuits
IS-649
In case equipment conforms to other international standard which ensure
equivalent or better performance than that specified under Clause 3.1, then
relevant Standards shall be forwarded with the bid.
GENERAL SERVICE CONDITION
The climatic conditions at site under which the equipment shall operate
satisfactorily are as follows:(a)
Maximum temperature of air in shade
50º
C
(b)
Minimum temperature of air in shade:
(c)
400C
(d)
320C
(e)
(f)
150
(g)
45
(h)
25
Maximum average daily ambient air temperature
- 2º
C
Maximum yearly weighted average ambient temperature
Maximum Humidity:
Average of rainy days per annum:
100%
Average number of days of thunderstorm per annum:
Average number of days of dust storm per annum:
(i)Average annual rainfall:
(j) Number of months of tropical monsoon per annum:
(k) Maximum wind pressure:
(l) Altitude (above mean sea level):
5.0
5.1
5.2
2280 mm
5 (May to Sept)
195Kg/m2
200 to 1000 m
GENERAL TECHNICAL SPECIFICATION
The Distribution transformer shall be 3-phase; oil immersed and shall have
wound/core type construction, and should be suitable for outdoor service in
hot and humid tropical climate.
The transformers and all its accessories shall be designed to withstand
without injury, the thermal and mechanical effects of any external short circuit
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Technical specification
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.10
5.11
5.12
5.13
6.0
6.1
6.2
to earth and of short circuits at the terminals of any winding of values and
duration specified in IS-2026.
Transformer shall be capable of withstanding thermal and mechanical stress
caused by symmetrical or asymmetrical faults on any winding. The calculation
for the same to be submitted along with the offer
The transformer shall be capable of being loaded in accordance with IS:
6600. There shall be no limitation imposed by bushings etc.
The transformer shall be suitable for continuous operation with frequency
variation of ±5% from normal 50Hz.Combined voltage and frequency variation
should not exceed the rated V/f ratio by 10%.
Transformer shall accept, without injurious heating, combined voltage and
frequency fluctuation, which produces the following over fluxing conditions:
i) 125% for 1 minute or 140% for 5 seconds
ii) Over fluxing withstand characteristics up to 140% shall be submitted along
with the bid.
The thermal ability to withstand short circuit shall be demonstrated by
calculation.
The maximum flux density in any part of the core and yokes, at normal voltage
and frequency of transformer shall be such that the flux density under over
voltage condition as per Clause 5.5 above shall not exceed 1.9 Tesla. The
detail calculation is to be shown as per Annexure-I.
The maximum magnetising current at 110% rated voltage shall not be more
than 125% of that at 100% rated voltage. Accordingly, the operating flux
density for design should be carefully chosen within the stipulated value to
achieve the above requirement. The Bidder shall quote the practical
achievable no load current at different percentages of rated voltage as
per Guaranteed Technical Particulars which will be verified during no
load test.
The maximum current density in any winding shall not exceed 1.50A/sq.mm
(Aluminium).
The sources of prime materials, place of manufacture, testing and inspection
should be shown as per the proforma enclosed in Annexure – VI.
SUPPRESSION OF HARMONICS
The transformers shall be designed with particular attention to the
suppression of harmonic voltage, especially the third and fifth, so as to
eliminate wave form distortion.
CENTRE OF GRAVITY
The center of gravity of the assembled transformers shall be low and as near
to the vertical center line as possible. The transformer shall be stable with or
without oil. If the center of gravity is eccentric relating to track either with or
without oil, its location shall be shown on the outline drawing.
GENERAL CONSTRUCTIONAL FEATURES
GENERAL
All material used shall be of best quality and of the class most suitable for
working under the conditions specified and shall withstand the variations of
temperature and atmospheric conditions without distortion or deterioration or
the setting up of undue stresses in any part and also without effecting the
strength and suitability of the various parts for the work which they have to
perform.
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Technical specification
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.10
6.11
6.12
7.0
7.1
7.1.1
7.1.2
7.2
7.2.1
7.2.2
7.2.3
7.3
7.3.1
7.4
7.4.1
Similar parts, particularly removable ones, shall be interchangeable.
Pipes, screws, studs, nuts and bolts used for external connections shall be as
per the relevant standards. Steel bolts and nuts exposed to atmosphere
shall be galvanized.
Nuts, bolts and pins used inside the transformers shall be provided with lock
washers or locknuts.
Exposed parts shall not have any pockets where water can collect.
Internal design of transformer shall ensure that air/gas is not trapped in any
location.
Material in contact with oil shall be such as not to contribute to the formation
of acid in oil. Surface in contact with oil shall not be galvanized or cadmium
plated.
Labels, indelibly marked, shall be provided for all identifiable accessories. All
label plates shall be of non corrodible material.
All internal connections and fastenings shall be capable of operating under
overloads and over-excitation, allowed as per specified standards without
injury.
Transformer and accessories shall be designed to facilitate proper operation,
inspection, maintenance and repairs.
No patching, plugging, shimming or other such means of overcoming defects;
discrepancies or errors will be accepted.
SURFACE PREPARATION & PAINTING
GENERAL
All paints, when applied in a normal full coat, shall be free from runs, sags,
wrinkles, patchiness, brush marks or other defects.
All primers shall be well marked into the surface, particularly in areas where
painting is evident and the first priming coat shall be applied as soon as
possible after cleaning. The paint shall be applied by airless spray according
to manufacturer‘s recommendations. However, where ever airless spray is
not possible, conventional spray be used with prior approval of purchaser.
CLEANING AND SURFACE PREPARATION:
After all machining, forming and welding has been completed, all steel work
surfaces shall be thoroughly cleaned of rust, scale, welding slag or spatter
and other contamination prior to any painting.
Steel surfaces shall be prepared by shot blast cleaning (IS:9954) to grade
Sq.2.5 of ISO 8501-1 or chemical cleaning including phosphating of the
appropriate quality (IS :3618)
Chipping, scraping and steel wire brushing using manual or power driven
tools cannot remove firmly adherent mill-scale. These methods shall only be
used where blast cleaning is impractical. Manufacturer to clearly explain such
areas in his technical offer.
PROTECTIVE COATING
As soon as all items have been cleaned and within four hours of subsequent
drying, they shall be given suitable anti-corrosion protection.
PAINT MATERIAL
Following are the types of paint which may be suitably used for the items to
be painted at shop and supply of matching paint to site: Heat resistant paint
(Hot oil proof) for inside surface.
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Technical specification
7.4.2
For external surfaces one coat of thermo setting powder paint or one coat of
epoxy primer followed by two coats of polyurethane paint. These paints can
be either air drying or stoving.
7.5
PAINTING PROCEDURE :
7.5.1 All prepared steel surfaces should be primed before visible re-rusting occurs
or within 4 hours, whichever is sooner. Chemical treated steel surfaces shall
be primed as soon as the surface is dry and while the steel surface is still
warm.
7.5.2 Where the quality of film is impaired by excess film thickness (wrinkling, mud
cracking or general softness) the supplier shall remove the unsatisfactory
paint coating and apply another coating. As a general rule, dry film thickness
should not exceed the specified minimum dry film thickness by more than
25%.
7.6
DAMAGED PAINTWORK :
7.6.1 Any damage occurring to any part of a painting scheme shall be made good
to the same standard of corrosion protection and appearance as that was
originally applied.
7.6.2 Any damaged paint work shall be made good as follows:
7.6.2.1
The damaged area, together with an area extending 25 mm around its
boundary, shall be cleaned down to bare metal.
7.6.2.2
A priming coat shall be immediately applied, followed by a full paint
finish equal to that originally applied and extending 50 mm around the
perimeter of the original damage.
7.6.2.3
The repainted surface shall present a smooth surface. This shall be
obtained by carefully chamfering the paint edges before and after priming.
7.7
DRY FILM THICKNESS :
7.7.1 The maximum extent practicable the coats shall be applied as a continuous
film of uniform thickness and free of pores. Overspray, skips, runs, sags and
drips should be avoided. The different coats may or may not be the same
colour.
7.7.2 Each coat of paint shall be allowed to harden before the next is applied as
per manufacturer‘s recommendations.
7.7.3 Particular attention must be paid to full film thickness at the edges.
7.7.4 The requirements for the dry film thickness (DFT) of paint and the materials
to be used shall be as given below:
Sl.No Paint type
Area to
painted
1.
inside
outside
01
01
of Total
dry
thickness
(microns)
30
60
outside
outside
inside
01
02
01
30
25 each
35/10
2.
Thermo setting powder
paint
Liquid Paint
a) Epoxy (primer)
b) P.U.Paint (Finish coat)
c) Hot oil paint/Varnish
be No.
coats
film
(min)
7.8
TESTS FOR PAINTED SURFACE:
7.8.1 The painted surface shall be tested for paint thickness.
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Technical specification
7.8.2 The painted surface shall pass the cross hatch adhesion test and impact test
as acceptance tests and Salt spray test and Hardness test as type test as per
the relevant ASTM standards. Note: The paint work done shall be
guaranteed for a minimum period of 5 years from the date of receipt of the
equipment.
8.0
TRANSFORMER TANK
8.1
The Transformer tank and cover shall be fabricated from high-grade low
carbon plate steel of tested quality. The transformer tank shall be of robust
construction rectangular/octagonal/round/elliptical in shape. The sheet
thickness of 3.15 mm for the bottom and top and not less than 2.5 mm sides
upto and including 25 KVA, 5.0 mm and 3.15 mm respectively for
transformers of more than 25 kVA and upto and including 100 KVA, above
100KVA it should be 6.0mm and 4.0 mm. Tolerances as per IS: 1852 shall be
applicable.
8.2
Transformers upto 100 kVA, there shall be no joints at corners and there shall
not be more than 2 joints in total.
8.3
The tank plate and lifting lugs shall be of such strength that the complete
transformer filled with oil may be lifted by means of lifting shackle.
8.4
All beams, flanges, lifting lugs, braces and permanent parts attached to the
tank, shall be welded and where practicable, they shall be double welded.
8.5
The main tank body of the transformer without oil, shall be capable of
withstanding pressure of 225 mm of Hg. Permanent deflection, when
subjected to vacuum, shall not be more than the values as given below:
please check with 8.6
(All figures in
mm)
Horizontal length of flat plate
Permanent deflection
Up to and including 750
5.0
751 to 1250
6.5
1251 to 1750
8.0
1751 to 2000
9.5
2001 to 2250
11.0
2251 to 2500
12.0
2501 to 3000
16.0
Above 3000
19.0
8.6
8.7
8.8
The tank shall further be capable of withstanding a pressure of 0.8 kg/sq.cm
(g) and a vacuum of 0.7 kg/sq.cm (g) without any deformation.
All bolted connections to the tank shall be fitted with suitable oil-tight gaskets,
which shall give satisfactory service under the operating conditions and
guaranteed temperature rise conditions. Special attention shall be given to the
methods of making the hot oil-tight joints between the tank and the cover as
also between the tank cover and the bushings and all outlets to ensure that
the joint can be remade satisfactorily at site and with ease, with the help of
semi-skilled labour. Where compressible gaskets are used, stops shall be
provided to prevent over-compression. The top cover gaskets should not be
exposed to atmosphere.
Suitable guides shall be provided for positioning the various parts during
assembly or dismantling.
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Technical specification
8.9
9.0
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
9.10
10.0
10.1
10.2
10.3
10.4
10.5
10.6
10.7
Tank stiffeners shall be provided for general rigidity and these shall be
designed to prevent retention of water.
CORRUGATED TANK
Corrugated tank may be offered for 63 and 100 kVA.
The transformer tank shall be of robust construction corrugation in shape and
shall be built up of CRCA sheets of 1.2 mm thick.
The internal clearance of tank shall be such that, it shall facilitate easy lifting
of core with coils from the tank, with CCA (core-coil assembly), HV & LV
bushings mounted on top cover.
All joints of tank and fittings shall be oil tight and no bulging should occur
during service.
The tank design shall be such that the core and windings can be lifted freely.
The tank plate shall be such strength that the complete transformer when
filled with oil may be lifted bodily by means of lifting lugs. Inside of the tank
shall be painted with hot oil resistant paint.
Corrugation panel shall be used for cooling. The transformer shall be capable
of giving continuous rated output without exceeding the specified temperature
rise.
2 Nos. welded heavy duty lifting lugs of MS plate 8 mm thick (min) suitably
reinforced are to be provided.
Top cover fixing bolts of galvanized iron and 6 mm Neoprene bonded cork
gaskets conforming to IS 4253 Part-II shall be placed between tank and
cover. The bolts outside tank shall have 2 flat washers and one spring
washer.
Tanks with corrugations shall be tested for leakage test at a pressure of
0.25kg/cm2 measured at the top of the tank.
The transformers with corrugation should be provided with a pallet for
transportation, the dimensions of which should be more than the length and
width of the transformer tank with corrugations.
TANK COVER
The transformer top shall be provided with a detachable tank cover with bolted
flanged gasket joint. The surface of the cover shall be suitably sloped so that
it does not retain rainwater.
Each tank cover shall be of adequate strength and shall not distort when lifted.
Inspection opening shall be provided as necessary to give easy access to
bushing. Each inspection opening shall be of ample size for the purpose for
which it is provided, The tank cover and inspection cover shall be provided
with suitable lifting arrangements.
The tank cover shall be fitted with pockets for thermometer (at the center of
the top cover).
The thermometer pockets shall be fitted with a captive screw top to prevent
the ingress of water.
The tank cover is to enclose the flanged gasket.
Bushings, covers of inspection openings, etc. shall be designed to prevent
ingress of water into or leakage of oil from the tank.
HV bushings are to be mounted on the top cover. However, for maintenance
purpose, the termination point of HV leads should have easy accessibility. All
bolted connection shall be fitted with weather proof, hot oil resistant gasket in
between, for complete oil tightness. If gasket is compressible, metallic
stoppers shall be provided to prevent over compression.
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11.0 Clamping etc of DTR
11.1 The suitable clamping device should be provided for top and bottom of the
transformer in case where it will be mounted on pole. The clamping device
should suitable for both PSC and Steel Tubular poles.
11.2 For pad mounted transformer, to prevent movement during earthquake,
clamping devices shall be provided for fixing transformer to the foundation.
The bidders shall supply necessary bolts for embedding of the concrete
foundation. The arrangement shall be such that the transformer can be fixed
to or unfastened from these bolts as desired. The fixing of the transformers to
the foundations shall be so designed to withstand the seismic events to the
extent that a static co-efficient of 0.5g, applied to the direction of least
resistance to that loading will not cause the transformer or clamping devices
as well as bolts to be over stressed.
12.0 CORE (MAGNETIC CIRCUIT) AND CONSTRUCTIONAL FEATURES OF
CORE
12.1 The magnetic circuit shall be constructed from high grade cold rolled nonageing grain oriented silicon steel lamination of M4 or better with thickness
of less than or equal to 0.27 mm. The material should be coated with hot oil
proof insulation. The core shall be stress relieved by annealing under inner
atmosphere if required.
12.2 Only primary core material is to be used. The bidder should offer the core for
inspection and approval by the purchaser or third party Inspection Agency
during the manufacturing stage. Bidder‘s call notice for the purpose should be
accompanied with the following document as applicable as a proof towards
use of Prime Core material.
(a) Invoice of supplier,
(b) Mill‘s test certificate.
(c) Packing list,
(d) Bill of loading,
(e) Bill of entry certificate to customs
Core material should be directly procured from either the manufacturer
or their accredited marketing organisation of repute and not through any
agent.
It is preferable for the manufacturer to have in house numeric controlled
Core cutting facility for better control of quality and also to avoid any
mixing of Prime Core material with second‟s materials. Core cutting
machine number and drawings are to be furnished.
12.3 The following procedure is to be adopted for those manufacturers who have
no in-house core-cutting facility:
(1) The bidder should specify the grade, thickness of core material in the offer
along with submission of all graphs/ documents, relating to the grade of
core material, offered by them.
(2) The documents, as mentioned above should be submitted to APDCL
along with the following informations:
a) Purchase order No. & Date.
b) No. of packed coils with package Nos.
c) Gross weight.
d) Net weight
e) Port of loading.
f) Port of discharge.
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g) Grade and thickness of core material.
i) Any other information, as mentioned on the body of packed coils.
12.4
12.5
12.6
12.7
12.8
12.9
12.10
12.11
12.12
12.13
12.14
13.0
13.1
13.2
(3) The manufacturer in its offer will mention the names of at least three Subvendors, to whom they intend to assign their core cutting. Such subvendors should have been approved by other Electricity Boards/ Electrical
utilities and are accredited by some International recognised certification
body like ISO: 9000 etc., to ensure that a minimum quality parameters and
tolerances are maintained. The experience, the details of core-cutting
facilities, finishing and testing facilities etc., as available with such subvendors should be clearly outlined in the bid.
(4) On award of contract, the Transformer Manufacture is to assign the corecutting to such sub-vendor(s) for which approval is to be given by APDCL
or its successor companies.
The laminations shall be free of all burrs and sharp projections. Each
sheet shall have an insulating coating resistant to the action of hot oil.
The design of magnetic circuit shall be such as to avoid static discharges,
development of short circuit paths within itself or to the earthed clamping
structure and production of flux component at right angle to the plane of the
lamination which may cause local heating.
All steel sections used for supporting the core shall be thoroughly shot or sand
blasted, after cutting, drilling and welding.
The finally assembled core with all the clamping structures shall be free from
deformation and shall not vibrate during operation. The core shall be carefully
assembled and rigidly clamped to ensure adequate mechanical strength.
The core clamping structure shall be designed to minimize eddy current loss.
The framework and clamping arrangements shall be securely earthed.
The supporting frame work of the cores shall be so designed as to avoid the
presence of pockets which would prevent complete emptying of the tank
through the drain valve or cause trapping of air during filling.
The oxide/silicate coating given on the core shall be adequate; however,
laminations can be insulated by the manufacturers if considered necessary.
All parts of the cores shall be of robust design capable of withstanding any
shocks to which they may be subjected during lifting, transport, installation
and service.
Adequate provision shall be made to prevent movement of the core and
winding relative to the tank during transport and installation or while in service.
No-load current shall not exceed 3% of full load current and will be measured
by energizing the transformer at 433 volts, 50Hz frequency. Increase of
voltage of 433 volts by 12.5% shall not increase the no-load current by 6%
(maximum) of full load current.
For AMORPHOS CORE METAL
The core shall be high quality amorphous ribbons having very low loss formed
into wound cores of rectangular shape, bolted together to the frames firmly to
prevent vibration or noise. The complete design of core must ensure
permanency of the core loss with continuous working of the transformers. The
value of flux density allowed in the design shall be clearly stated in the offer.
Curve showing the properties of the metal shall be attached with the offer.
The transformer core shall be suitable for over fluxing (due to combined effect
of voltage and frequency) up to 12.5% without injurious heating at full load
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13.3
14.0
14.1
14.2
14.3
15.0
15.1
conditions and shall not get saturated. The bidder shall furnish necessary
design data in support of this situation.
No-load current shall not exceed 2% of full load current and will be measured
by energizing the transformer at 433 volts, 50Hz frequency. Increase of
voltage of 433 volts by 12.5% shall not increase the no-load current by 5%
(maximum) of full load current.
INTERNAL EARTHING
EARTHING OF CORE CLAMPING STRUCTURE
i) All internal metal parts of the transformer, with the exception of individual
laminations, core bolts and their individual clamping plates shall be
earthed.
ii) The top clamping structure shall be connected to the tank by a copper
strap. The bottom clamping structure shall be earthed by one or more of
the following methods:
a) By connection through vertical tie-rods to the top structure.
b) By a connection to the top structure on the same side of the
core as the main earth connection to the tank.
EARTHING OF MAGNETIC CIRCUIT
i) The magnetic circuit shall be connected to the clamping structure at one
point only
SIZE OF EARTHING CONNECTIONS
Earthing strip should be tin copper and size will be approved by the purchaser
after getting suppliers offer.
WINDING
GENERAL
i)
The current density of Aluminium in any part of the windings shall not
exceed 1.50 Amps/Sq. mm.
ii) All windings shall be made of electrolytic high conductivity Aluminum
for transformer of capacity up to 200 KVA and shaped and braced to
provide for expansion and contraction due to temperature changes.
Winding shall be fully insulated as defined in IS: 2026. All neutral points
shall be insulated for the voltage specified in IS: 2026. The winding
shall be so designed that all coil assemblies of identical voltage, rating
shall be interchangeable.
iii) Number of HV coils per phase should not be less than four (4) for 63,
100 & 200 kVA and single HV coil for 16 & 25 kVA with the type
Crossover/Sectional. Number of secondary (LV) coil should be one
with spiral type winding construction.
iv) LV winding shall be such that neutral formation will be at top.
v) Conductor covering for HV winding conductor should be DPC with
minimum 0.35 mm thickness and for LV conductor DPC with minimum
0.40 mm thickness.
vi) Interlayer insulation shall be Nomex/Epoxy dotted Kraft Paper.
vii) Distribution Transformers shall be designed to withstand the impulse
and power frequency test voltages as per IS: 2026.
viii) Magnitude of impulse surges transferred from HV to LV windings by
induction and capacitance coupling shall be limited to B.I.L. of LV
winding
ix) The completed core and coil assembly shall be dried in vacuum at not
more than 0.5mm of mercury absolute pressure and shall be
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immediately impregnated with oil after the drying process to ensure the
elimination of air and moisture within the insulation. Vacuum may be
applied in either vacuum over or in the transformer tank
x) Winding shall be subjected to a shrinking and seasoning process, so
that no further shrinkage occurs during service. Adjustable devices
shall be provided for taking up possible shrinkage in service.
xi) Winding shall not contain sharp bends which might damage the
insulation or produce high dielectric stresses. No strip conductor wound
on edge shall have width exceeding six times the thickness.
xii) Varnish application on coil windings may be given only for mechanical
protection and not for improvement in dielectric properties. In no case
varnish or other adhesive be used which will seal the coil and prevent
evacuation of air and moisture and impregnation by oil.
xiii) The insulation of transformer windings and connection shall be free
from insulating composition liable to soften, ooze out ,shrink or
collapse during service and be non catalytic and chemically inactive in
transformer oil.
xiv) The coil clamping arrangement and the finished dimensions of any oil
ducts shall be such as will not impede the free circulation of oil through
the ducts.
xv) Terminals of all windings shall be brought out of the tank through
bushings for external connections
xvi) The winding shall be so designed that all coil assemblies of identical
voltage ratings shall be interchangeable and field repairs to the winding
can be made readily without special equipment. The coils shall have
high dielectric strength
xvii) All leads from windings to terminals shall be rigidly supported to
prevent injury from vibration. Guide tubes may be used where possible.
15.2 BRACING OF WINDINGS
15.2.1 The windings and connections of all transformers shall be braced to withstand
shocks, which may occur during transport or due to switching and other
transient conditions during service.
i)
Coil clamping rings shall be of suitable insulating material.
ii) Permanent current carrying joints in the windings and leads shall be
welded or brazed. Clamping bolts for current carrying parts inside oil
shall be made of oil resistant material which shall not be affected by
acidity in the oil steel bolts, if used, shall be suitably treated.
iii) Adequate barriers shall be provided between coils and core and
between high and low voltage coil. End turns shall have additional
protection against abnormal line disturbances.
iv) Coil should be clamped by 8 (eight) numbers of 12 mm dia tie rods
between top and bottom yoke support channels.
16.0 BOLTS AND NUTS
16.1 Steel bolts and nuts exposed to atmosphere with suitable finishes like
cadmium plated or zinc plated passivated will be used for diameter above 6
mm.
16.2 Brass bolts and nuts of less than 6 mm shall not be used for electrical
connections. Where smaller size is required, stainless steel or phosphor
bronze may be used. Sizes and threads will be as per Indian Standard,
wherever, available, otherwise equivalent British Standard will be followed.
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16.3 All nuts and bolts and pins shall be locked in position with the exception of
those external to the transformer. The bolts shall be fitted in such a manner
that in the event of the nut working loose and falling off, the bolts will remain in
position.
16.4 All bolts, nuts and washers in contact with non-ferrous parts which carry
current and are exposed to atmosphere shall be of phosphor bronze, where
transfer of current is through bolts.
16.5 If bolts and nuts are placed that are in accessible by means of ordinary
spanners, suitable special spanners shall be provided by the supplier.
17.0 INSULATION MATERIAL:
17.1 Electrical grade insulation epoxy dotted Kraft Paper/Nomex and pressboard of
standard make or any other superior material subject to approval of the
purchaser shall be used.
17.2 All spacers, axial wedges / runners used in windings shall be made of precompressed Pressboard solid, conforming to type B 3.1 of IEC 641 – 3 – 2 .
For cross-over coil winding of HV all spacers shall be properly sheared and
dovetail punched to ensure proper locking. All axial wedges / runners shall be
properly milled to dovetail shape so that they pass through the designed
spacers freely. Insulation shearing, cutting, milling and punching operations
shall be carried out in such a way, that there should not be any burr and
dimensional variations.
17.3 INSULATING OIL
17.3.1 The insulating oil for the transformers shall be of EHV grade, generally
conforming to IS: 335. No inhibitors shall be used in the oil.
17.3.2 The quantity of oil required for the first filling of the transformer and its full
specification shall be stated in the bid. The bidder shall quote the price of
transformer complete with first filling of oil.
17.3.3 The design and materials used in the construction of the transformer shall be
such as to reduce the risk of the development of acidity in the oil.
17.3.4 The supplier shall warrant that oil furnished is in accordance with the following
specifications.
a) Appearance
: The oil shall be clear and
transparent and free from
suspended matter or sediment
o
b) Density at 20 C Max:
0.89g/cm3
c) Kinematic Viscosity at 27oC Max: 27 CST
d) Interfacial at 27oC Min.:
0.03 N/m
e) Flash Point:
140oC
o
f) Pour Point Max:
-6 C
g) Neutralisation Value:
0.03 mg/KOH/g
(Total Acidity) Max
h) Electric Strength:
60 kV
(Breakdown Voltage) Min.
i) Dielectric dissipation factor:
0.05
tan delta at 90oC Max
j) Minimum specific resistance:
1 x 1012 ohm cm
(resistivity), at 90oC Min.
k) Oxidation Stability
i) Neutralisation value after Max:
0.40 mg/KOH/g
ii) Total sludge after oxidation max: 0.10% by weight
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l) Presence of oxidation Inhibotor:
The oil shall not contain
anti-oxidant Additives
25 ppm
m) Water content Max:
18.0 ACCESSORIES & FITTINGS
18.1 BUSHINGS:
18.1.1 The bushing shall conform to the relevant standards specified and shall be of
outdoor type. The bushing rods and nuts shall be made of brass material 12
mm diameter for HT bushings. Both the HV & LV bushings should be mounted
on top cover. The tests as per latest IS:2099 and IS:7421 shall be conducted
on the transformer bushings.
18.1.2 Bushing can be of porcelain/epoxy material. Polymer insulator bushings
conforming with relevant IEC can also be used. LV side bushings shall
invariably be either of epoxy material or polymeric type. The bidder is to
name at least 2/3 vendors of repute who are presently manufacturing
epoxy/polymeric bushings and APDCL will select the vendor from those of
offered at the time of detail engineering
18.1.3 For 11 KV, 17.5 kV class bushing and for 0.433 kV, 1.1 kV class bushing shall
be used.
18.1.4 Dimensions of the bushings of the voltage class shall conform to the
Standards specified and dimension of clamping arrangement shall be as per
IS:4257.
18.1.5 Minimum external phase to phase and phase to earth clearances of bushing
terminals shall be as follows :
Voltage
Clearance
Phase to phase
Phase to earth
11 kV
255 mm
140 mm
0.433 kV
75 mm
40 mm
18.1.6 Brazing of all inter connections, jumpers from winding to bushing shall have
cross section larger than the winding conductor. All the Brazes shall be
qualified as per ASME, section-IX.
18.2 TERMINAL CONNECTORS :
18.2.1 The HV bushing stems shall be provided with suitable terminal connectors as
per IS: 5082 so as to connect the jumper without disturbing the bushing stem.
Connectors shall be with eye bolts so as to receive conductor for HV.
Terminal connectors shall be type tested as per IS:5561.
18.2.2 Bird guards are to be provided for all HV bushings.
18.2.3 All LV bushing shall be provided with connectors in accordance with IS : 3347
(Part 1 /Section 1 & 2) and the connector shall be universal type suitable for
both horizontal and / or vertical take off.. The connector should have the
capacity to accommodate connection of at least 1-core 70 sq.mm to 120
sq.mm XLPE cable.
18.2.4 The terminal connectors to be supplied for both H.V. and L.V. side
18.2.5 The type of terminal connector, size of connector, material, and type of
installation shall be approved by the APDCL, as per installation requirement
while approving the equipment drawings.
18.3 EARTHING TERMINAL:
18.3.1 Two earthing pads (each complete with two nos. (2) tapped holes, M 8 bolts,
plain and spring washers) suitable for connection to 25x4 mm galvanised steel
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flat shall be provided each at position close to the two (2) diagonally bottom
corners of the tank.
19.0 Protection & Measuring Devices
A) Conservator Tank
i.
The conservator tank for 63KVA and above shall have adequate
capacity between highest and lowest visible levels to meet the
requirement of the expansion of the total cold oil volume in the
transformer from minimum ambient temperature to 90°C. The total
volume of conservator shall be 10% of total oil in the transformer.
ii.
It is desirable to create sump in the conservator for which the feed
pipe extension of 25mm will be required and the design of feed
pipe to transformer tank should be such that the oil from
conservator does not fall directly to the core & coil assembly.
iii.
The conservator should have one oil filling hole of 32 mm size with
gasketed cover. One air release plug of 15mm size will be
required.
iv.
The conservator tank shall be bolted into position so that it can be
removed for cleaning purposes.
v.
The conservator tank shall be fitted with prismatic oil level gauge
with minimum and maximum marking.
vi.
The conservator tank shall be provided in a position not to obstruct
the electrical connections to the transformers.
B) Pressure Relief Device
Pressure relief device may be provided at suitable locations which shall
be of sufficient size for rapid release of any pressure that may be
generated in the tank and which may result in damage to the equipment.
The device shall operate at the static pressure of less than the hydraulic
test pressure of transformer tank. It shall be mounted directly on the
tank.
C) Oil Preservation Equipment
(i) Oil Sealing Breather
The conservator shall be fitted with a dehydrating filter breather. It shall
be so designed that,
1) Passage of air is through a dust filter & Silica gel
2) Silica gel is isolated from atmosphere by an oil seal.
3) Moisture absorption indicated by a change in colour of the
crystals can be easily observed from a distance.
4) Breather is mounted not more than 1200 mm above rail top
level.
5) The breather should have at least 500g of silica gel.
19.1 RADIATORS & VALVES
19.1.1
RADIATORS
i)
Radiators shall be of press steel having thickness of 1.2 mm Cold
Rolled Continuously Annealed (CRCA) sheet and design should be
such that all painted surface can be thoroughly cleaned by hand.
ii)
The inlet header of Radiators should be put below the LV bushings in
such a way that in the event of oil leakage from LV bushings, the
circulation of oil through radiators are continuing. The arrangement to
be demonstrated at the time of detail engineering and will be verified
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during stage inspection. Failure of this arrangement will lead to total
rejection of offered lot
19.2 VALVES
19.2.1 Each transformer shall be provided with following valves on the tank:
a)
One fully pilfer proof valve below the top cover.
b)
One 15 mm air release plug.
20.0 FITTINGS AND ACCESORIES
20.1.1 The following fittings shall be provided on each transformer:
a) Conservator fitted with oil filling hole and cap.
b) Prismatic type oil gauge
c) Silica gel breather with oil seal.
d) Pressure relief device for main tank.
e) Pocket on tank cover (placed at mid position) for thermometers.
f) 9 kV, 5 KA lightning arrestors on HT side – 3 No.
g) Valve (32mm) shall be of globe type.
h) Earthing terminals with lugs- 2 nos.
i) Rating and diagram plate, non-detachable.
j) Lifting lugs for main tank.
k) Top tank clamping
l) Terminal connectors on the HV/LV bushing
m) Base channel of 75 x 40 mm, 460 mm long with holes to make them
suitable for fixing on a platform or plinth.
n) 5 year guarantee plate non detachable type
21.0 MISCELLANEOUS
i)
LIGHTNING ARRESTORS:
9 kV, 5 kA metal oxide lightning arrestors Distribution class type of
make CGL/Oblum/Rechem/LAMCO conforming relevant standard,
one number per phase shall be provided to be fitted under the HV
bushing. The LA should be clamped to HV side bushing with a
galvanized earth strip of size 25x4 mm with two nos of M8 size bolt
hole along with galvanized nut & bolts and the strip should run near
to pole for pole mounted transformer so that the riser from the
ground can be connected properly
ii) NAME PLATE
Transformer rating plate shall contain the information as given in
clause 15 of IS-2026 (Part-I). The details on rating plate shall be
finalised during the detailed engineering.
22.0 LOSSES
22.1 The bidder shall guarantee the total losses at 50% and 100% load condition
(at rated voltage and frequency and at 750C) as per Table – I below.
. Table: I
Rating
Max. Losses at 50% loading
Max. Losses at 100% loading
(KVA)
(Watts)
(Watts) at 750C
16
150
480
25
210
695
63
380
1250
100
520
1800
200
890
2700
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22.2 The above losses are maximum allowable and there would not be any “+ve”
tolerance. Bids with higher losses than the specified values would be
treated as non responsive.
22.3 The bidder shall guarantee individually the no-load loss and load loss (Table:
II) without any positive tolerance.
Table: II
Rating
No load
in Watts
Load losses DAMAGES
in Watts (Max)
at EXCESSIVE LOSSES
CAPITALISATION
OFloss
LOSSES
AND LIQUIDATED
FOR
0
(KVA)
(Max)
75 C
16
50
400
25
80
520
63
145
940
100
220
1180
200
380
2000
22.4 Transformers with losses less than those specified above will be capitalized
during bid evaluation process as per Clause No 22.6
22.5 Since IS: 2026 allows certain tolerances on the transformer losses, the
bidders are requested to indicate whether the figures given for guaranteed
losses in the schedule of guaranteed technical particulars are with or without
such tolerances. If tolerances are applicable, the limits for the same should be
indicated. In the absence of any information to this effect, the figures for noload losses and load losses will be increased by 10% as provided in the IS.
Any change in the figures assigned for transformer losses will not be
permitted after opening of bids and bid evaluation will be carried out on the
basis of information made available at the time of bid opening.
22.6 For the purpose of comparison of the different bids, the capitalised cost of
each transformer shall be considered. Capitalised cost of the transformer for
the purpose of tender evaluation only shall be calculated as given below:
Capitalised cost in Rs = IC+328 Wi(g) +181 Wc(g)
Where,
IC= Quoted price of transformer in Rs
Wi(g) = Guaranteed no load loss in Watt
Wc(g)= Guaranteed load loss (copper loss) in Watt
22.7 The loss figures (both guaranteed & test) for the purpose of calculation shall
be at rated frequency and voltage and at principal tap and 75º C.
22.8 If losses are quoted with tolerance limit, then upper positive value will be
considered for capitalization.
22.9 Penalties will be applicable if any one or more test loss figures of no-load loss
and total losses exceed the corresponding guaranteed figures. The penalties
will be calculated as follows: (a) For No-load loss, Penalty (in rupees) = {Wi (t) – Wi (g)} x 2R1.
(b) For load loss, Penalty (in rupees)
= {WT (t) – Wi (t) - WI (g)} x
2R2
Where,
WT (t) = Total loss (test value) in W.
WT (g) = Total loss (guaranteed value) in W.
Wi (t) = No-load loss (test value) in W.
Wi (g) = No-load loss (guaranteed value) in W.
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22.10
22.11
23.0
23.1
23.2
24.0
24.1
25.0
25.1
W1 (g) = Load loss (guaranteed value) in W.( Copper loss )
R1
= Rs.328/R2
= Rs.181/For the purpose of penalty computation, the test figures of the no-load and the
total losses of each transformer will be compared with the corresponding
guaranteed figures.
Calculation of detail losses including flux density and no load current
are to be furnished for copper loss, iron loss indicating corresponding
copper weight and core weight and considering all parameters and also
supported by the drawings showings details of diameter and height of
winding and core duly signed by manufacturer‟s design personnel. The
loss calculation is to be shown as per proforma in Annexure – II.
Temperature rise: The temperature rise over ambient shall not exceed the
limit given below:
Top oil temperature rise measured by thermometer
: 350C
Winding temperature rise measured by resistance method
:
400C
Bids not meeting the above limits of temperature rise will be treated as
non-responsive.
MCCB BOX
MCCB of defined rating and make shall have to be put for LV side protection.
The specification of MCCB and the box shall be as per Schedule-C
TESTING AND INSPECTION
TESTS
(i)
The Supplier shall carry out a comprehensive inspection and testing
programme during manufacture of the transformer. An detail of
inspection is given in this specification. The manufacturer will submit a
testing and inspection plan at the time of bidding.
(ii)
The procedure for testing shall be in accordance with IS 1180/2026 as
the case may be except for temperature rise test.
(iii)
The supplier shall carry out all routine tests on each transformers.
(iv)
Special tests other than type and routine tests, as agreed between
purchaser and bidder shall also be carried out as per the relevant
standards.
(v)
Before dispatch each of the completely assembled transformers shall
be subjected to the routine tests at the manufacturer‘s works.
(vi)
The requirements of onsite tests are as listed in these specifications.
(vii) Certified test report and oscillograms shall be furnished to the
Purchaser for evaluation. The Supplier shall also evaluate the test
results and rectify the defects in the equipment based on his and the
Purchaser‘s evaluations of the tests without any extra charges to the
Purchaser. Manufacturer‘s Test Certificates in respect of all associated
auxiliary and ancillary equipment shall be furnished.
(viii) The bidder shall state in his proposal the testing facilities available at
his works. In case full testing facilities are not available, the bidder shall
state the method proposed to be adopted so as to ascertain the
transformer characteristics corresponding to full capacity testing.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
25.1.1 ROUTINE TESTS: (To be conducted on each transformer)
25.1.1.1
Ratio, polarity, phase sequence and vector group.
25.1.1.2
No Load current and losses at services voltage and normal frequency.
25.1.1.3
Load Losses at rated current and normal frequency.
25.1.1.4
Impedance Voltage test.
25.1.1.5
Resistance of windings at each tap.
25.1.1.6
Insulation Resistance.
25.1.1.7
Induced over voltage withstand test.
25.1.1.8
Separate source voltage withstand test.
25.1.1.9
Neutral current measurement- The value of zero sequence current in
the neutral of the star winding shall not be more than 2% of the full load
current.
25.1.1.10
Oil samples (one sample per lot) to comply with IS 1866.
25.1.1.11
Measurement of no load losses and magnetizing current at rated
frequency and 90%, 100% and 110% rated voltage.
25.1.1.12
Pressure and vacuum test for checking the deflection.
25.1.2 TYPE TESTS TO BE CONDUCTED ON ONE UNIT:
25.1.2.1
Temperature rise test.
25.1.2.2
Impulse voltage test: with chopped wave of IS 2026 Part-III, BIL should
be 95 KV peak.
25.1.2.3
Short circuit withstand test: Thermal and dynamic ability.
25.1.2.4
Air Pressure Test: As per IS – 1180.
25.1.2.5
Magnetic Balance Test.
25.1.2.6
Un-balanced current test: The value of unbalanced current indicated by
the ammeter shall not be more than 2% of the full load current.
25.1.2.7
Noise level measurement.
25.1.2.8
Measurement of zero-phase sequence impedance.
25.1.2.9
Measurement of Harmonics of no-load current.
25.1.2.10
Transformer tank shall be subjected to specified vacuum. The tank
designed for vacuum shall be tested at an internal pressure of 0.35
Kg/cm2 absolute (250 mm of Hg) The permanent deflection of flat
plates after the vacuum has been released shall not exceed the value
given below:
Horizontal length of flat plate
Permanent deflection
Up to and including 750
5.0
751 to 1250
6.5
1251 to 1750
8.0
1751 to 2000
9.5
2001 to 2250
11.0
2251 to 2500
12.0
2501 to 3000
16.0
Above 3000
19.0
25.1.2.11
25.1.2.12
Pressure relief device test.
Short Circuit Test and Impulse Voltage Withstand Tests: In case
the transformers proposed for supply against the order are not exactly
as per the tested design, the supplier shall be required to carry out the
short circuit test and impulse voltage withstand test at their own cost in
the presence of the representative of the purchaser.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
25.1.2.13
The supply shall be accepted only after such test is done successfully,
as it confirms on successful withstand of short circuit and healthiness of
the active parts thereafter on un-tanking after a short circuit test.
25.1.2.14
Apart from dynamic ability test, the transformers shall also be required
to withstand thermal ability test or thermal withstand ability will have to
be established by way of calculations.
25.1.2.15
It may also be noted that the APDCL reserves the right to conduct short
circuit test and impulse voltage withstand test in accordance with the
IS, afresh on each ordered rating at purchaser cost, even if the
transformers of the same rating and similar design are already tested.
This test shall be carried out on a transformer to be selected by the
purchaser either at the manufacturer‘s works when they are offered in a
lot for supply or randomly from the supplies already made to
purchaser‘s stores. The findings and conclusions of these tests shall be
binding on the supplier.
25.1.2.16
Type test certificates for the tests carried out on prototype of same
specifications shall be submitted along with the bid. The purchaser may
select the transformer for type tests randomly.
25.1.3 ACCEPTANCE TEST:
25.1.3.1
At least 10% transformers of the offered lot (minimum of one) shall be
subjected to the following routine/acceptance in presence of APDCL‘s
representative at the place of manufacture before dispatch without any extra
charges. The testing shall be carried out in accordance with IS 1180 and IS
2026.
25.1.3.2
Checking of weights, dimensions, fittings and accessories, tank sheet
thickness, oil quality, material, finish and workmanship as per GTP and
contract drawings.
25.1.3.3
Physical verification of core coil assembly and measurement of flux
density of one unit of each rating, in every inspection with reference to short
circuit test report.
25.1.3.4
Temperature rise test on one unit of the total offered quantity.
25.1.3.5
At least one transformer of the supplied lot shall be subjected to
tests by a third party (preferably ERDA or CPRI) at the purchaser’s
cost. In case of Failure in such test, the entire lot will be rejected by
APDCL and the cost of the tests will have to be borne by the supplier.
25.2
INSPECTION
25.2.1 Inspection and testing of transformer oil:
25.2.1.1
To ascertain the quality of transformer oil, the original manufacturer‘s
test report should be submitted at the time of inspection. Arrangement
should also be made for testing of transformer oil, after taking out the sample
from manufactured transformers and tested in the presence of APDCL‘s
representative.
25.2.2 STAGE INSPECTION: To ensure about the quality of transformers, the
inspection shall be carried out by the APDCL‘s representative at following two
stages:25.2.2.1
Online
anytime
during
receipt
of
raw
material
and
manufacture/assembly whenever the APDCL desires.
25.2.2.2
At finished stage i.e. transformers are fully assembled and are ready
for dispatch.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
25.2.2.3
The stage inspection shall be carried out in accordance with Annexure
– IV.
25.2.2.4
After the main raw-material i.e core and coil material and tanks are
arranged and transformers are taken for production on shop floor and a few
assembly had been completed, the firm shall intimate the APDCL in this
regard, so that an officer for carrying out such inspection could be deputed,
as far as possible within seven (7) days from the date of intimation. During
the stage inspection a few assembled core shall be dismantled to ensure
that the CRGO laminations used are of good quality. Further, as and when
the transformers are ready for dispatch, an offer about the readiness of
transformers, for final inspection for carrying out tests as per relevant IS shall
be sent by the firm along with Routine Test Certificates. The inspection shall
normally be arranged by the APDCL at the earliest after receipt of offer for
pre-delivery inspection. The proforma for pre delivery inspection of
Distribution Transformers is placed at Annexure – V.
25.2.2.5
In case of any defect/defective workmanship observed at any stage by
the APDCL‘s Inspecting Officer, the same shall be pointed out to the firm in
writing for taking remedial measures. Further processing should only be
done after clearance from the Inspecting Officer/APDCL.
25.2.2.6
All tests and inspection shall be carried out at the place of manufacture
unless otherwise specifically agreed upon by the manufacturer and APDCL
at the time of purchase. The manufacturer shall offer the Inspector
representing the APDCL all reasonable facilities, without charges, to satisfy
him that the material is being supplied in accordance with this specifications.
This will include Stage Inspection during manufacturing stage as well as
active part inspection during Acceptance Tests.
25.2.2.7
APDCL shall have every right to appoint a third party inspection to
carry out the inspection process.
25.2.2.8
The APDCL has the right to have the test carried out at his own cost by
an independent agency wherever there is a dispute regarding the quality
supplied. APDCL has right to test 1% of the supply selected either from the
stores or field to check the quality of the product. In case of any deviation
APDCL has every right to reject the entire lot or penalize the manufacturer,
which may lead to blacklisting, among other things.
25.2.2.9
Test Reports for bought out items:
The supplier shall submit the test reports for all bought out/sub contracted items for
approval.
Bushings, connectors, lightning arrestors and any other item required to complete
the works.
Porcelain, bushings, insulating oil and other associated equipment shall be tested
by the supplier in accordance with relevant IS. If such equipment are purchased by
the supplier on a sub-contract, he shall have them tested to comply with these
requirements.
25.3 TEST REPORTS TO BE SUBMITTED ON THE FOLLOWING FACTORY TEST PRIOR TO
INSPECTION:
i)
All standard routine tests in accordance IS: 2026 shall be carried out
on each transformer..
ii) Following additional tests shall also be carried out as routine tests on
each transformer:
a)
Magnetic Circuit Test
b)
Oil leakage test on transformer
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
iii)
Following type tests shall be conducted on the transformer of each
rating:
a)
Temp. rise test as per IS: 2026 (Part-I). This test shall be carried
out at maximum negative tap.
b)
Lightning Impulse Test shall be carried out in accordance with
IS-2026 on one transformer of each rating.
iv) Six (6) sets of certified test reports and oscillographs shall be submitted
for evaluation prior to despatch of the equipment. The supplier shall
also evaluate the test results and shall correct any defect indicated by
his and Purchaser‘s evaluation of the tests without charge to the
Purchaser.
v) All auxiliary equipment shall be tested as per the relevant IS. Test
certificates shall be submitted for bought out items.
25.4 TANK TESTS
a) Routine Tests
i) Fabrication Stage
The tank shall be tested for leakage by being completely filled with air
and applying a pressure equal to the normal pressure plus 35 KN/m 2
measured at the base of the tank. The pressure shall be maintained
for a period of not less than one hour and during that time no leak
shall occur.
ii)Transformer assembly stage
Oil pressure test to be conducted on tank and all other accessories
and assembled for routine test by being completely filled with oil at a
pressure equal to the twice the normal head of oil or to normal
pressure plus 35 KN/m2 whichever is lower . The pressure shall be
maintained for a period of eight hour and during that time no leak
shall occur.
b) Type Test
Pressure Test
Where required by the Purchaser, one transformer tank of each size
together with its radiator, conservator vessel and other fittings shall
be subjected to a pressure corresponding to twice the normal head of
oil or to the normal pressure plus 35 KN/m 2 whichever is lower,
measured at the base of the tank and maintained for eight hours
during which no leakage shall occur.
25.5 PRE-SHIPMENT CHECK AT MANUFACTURERS WORKS:
i)
Check for proper packing and preservation of accessories like
radiators, bushings, PRV, dehydrating breather, rollers, conservator
etc.
ii) Check for proper provision of bracing to arrest the movement of core
and winding assembly inside the tank.
iii) Gas tightness test to conform tightness.
25.6 RECEIPT AND STORAGE CHECKS
a. Check and record condition of each visible parts of the transformers etc.
for any damage.
b. Check for oil and any leakage of oil from the transformer tank, radiators
etc.
c. Visual check HV/ LV bushings for any crack.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
26.0
26.1
27.0
27.1
d. Check for IR between HV-E, LV-E and HV – LV.
e. Check for oil BDV and water content.
f.
Thermometer pockets are to be filled with oil.
g. Colour of Silica gel is blue
h. Bushing arcing horn is set correctly for required gap distance.
i.
Oil is at correct level in the bushing, conservator and tank.
REJECTION
The Purchaser may reject any transformer if during tests or service any of the
following conditions arise:
i)
No load loss exceeds the guaranteed value by 20% or more.
ii) Load loss exceeds the guaranteed value by 20% or more.
iii) Impedance value exceeds the guaranteed value by ( -) 10% or more.
iv) The difference in impedance values of any two phases during single
phase short circuit impedance test exceeds 2% of the average value
guaranteed by the vendor.
v) Oil or winding temperature rise exceeds the specified value.
vi) Transformer fails on impulse test.
vii) Transformer fails on power frequency voltage withstand test.
viii) Transformer is proved to have been manufactured not in accordance
with the agreed specification.
DRAWINGS and CALCULATIONS FOR SUBMISSION WITH THE BID
The Bidder shall furnish with his bid following drawings incorporating the
details mentioned hereunder.
a)
General outline drawing showing dimensions and overall
dimensions, sectional view, core and coil assembly drawing, net
weights and shipping weights, quantity of insulating oil, spacing
of wheels, location off load tap changers etc.
b)
Details of the sectional view of core and winding showing the
core frame size, coil dia and length, conductor size, lead support
etc.
c)
Hot spot temperature calculation.
d)
Demonstration to withstand thermal ability as per IS:2026
e)
Calculation of thermal time constant.
f)
Calculation for thermal and mechanical stress caused by
symmetrical or asymmetrical faults on any winding.
g)
Calculation of detail losses including flux density and no load
current are to be furnished for copper loss, iron loss indicating
corresponding copper weight and core weight and considering
all parameters and also supported by the drawings showings
details of diameter and height of winding and core duly signed
by manufacturer‘s design personnel.
g)
GA drawings/details of various types of bushings and
connectors.
h)
Illustrative & descriptive literature of the Transformer
i)
List of customers to whom similar equipments have been
supplied.
j)
Type test certificates from a recognized institute preferably CPRI
of equipment of similar design and rating.
k)
Performance report of equipment of similar design and rating
which is in satisfactory operation for at least three years.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
305
Technical specification
Performance report issuing officer‘s rank should be S.E./ DGM
and above of the utility.
28.0 QUALITY ASSURANCE PLAN:
The bidders shall invariably furnish the following informations in respect of quality
assurance, failing which, offers are liable to be ignored.
(a)
(i)
List of important raw materials (CRGO laminations, wires and
strips, transformer oil, insulating paper, press board, bushings and terminal
connectors etc.)
(ii)
Name of Suppliers/ sub suppliers
(iii)
List of standards which are followed during testing of raw
materials.
(iv)
List of test carried out on raw materials along with test
certificate.
(c) List of manufacturing facilities.
(d) Level of automation achieved.
(e) Quality control on stages of manufacturing process along with inspection
reports.
(f) List of testing equipments available along with valid calibration certificates.
Manufacturer shall posses 0.1 accuracy class instruments for
measurement of losses.
Quality Assurance Plan (QAP) with hold points for Purchaser‘s Inspection
as per Annexure – III.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
306
Technical specification
29.0
DATA SHEET
SL
NO
DESCRIPTION
1.
2.
3.
Continuous KVA Ratings (CMR)
Number of phases
Rated voltage kV
i) Primary (HV)
ii) Secondary (LV)
4.
5.
6.
Highest System Voltage, kV
i) Primary (HV)
ii) Secondary (LV)
Rated frequency, Hz.
Connection of HV, LV
7.
8.
9.
TRANSFORMER CLASS
11/0.433-0.250 KV
16,25,63,100, 200 KVA
3
11
0.433
12
1.1
50±5%
HV Delta & LV Star with
neutral solidly earthed
Solidly earthed
DYN 11
Method of system earthing
Vector group
Insulation Level:
i) PF withstand voltage, kV
28
(rms.): HV
ii) PF withstand voltage, kV
3
(rms.): LV
iii) Lightening impulse voltage, kV
95
(peak) HV
10.
Minimum Insulation resistance at HV- E : > 2000 MΩ
200C
LV – E : > 1000 MΩ
11.
4.5%
Percentage Impedance at 75C
and at principal tap
12.
Maximum flux density at rated
1.6
KVA, Maximum System voltage
[12 KV/1.1 KV] and minimum
system frequency [48.5 HZ],
13.
Method of cooling
ONAN
14.
Type of tap changer
No tapping
15.
Clearance of air, mm
a) phase to phase, HV / LV
285 / 75
phase to earth, HV / LV
140 / 40
16.
Electrical Clearance, mm
a)
Core to LV:
3.5 (up to 100KVA)
b)
Between HV & LV
12
c)
HV Phase to Phase
10
d)
Between tank inside & top
150
of Yoke
40
e)
Between yoke to bottom
17.
Maximum current density
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
2.50 Amp / sq. mm for Copper
1.5 Amp/ sq.mm for Aluminium
Assam Power Distribution Company Ltd
307
Technical specification
SL
NO
DESCRIPTION
18.
Temperature Rise, 0C
(i) Winding
(measured
resistance.
(ii) Top
Oil
(measured
thermometer)
Bushings:
1. Rated voltage in kV
19.
TRANSFORMER CLASS
11/0.433-0.250 KV
by
35
40
by
1.1 HV bushing
12
1.2 LV bushing
1.1
1.3 Neutral bushing
2. Rated current in Ampere
1.1
2.1 HV bushing
As per IS: 3347 Part III
(Section 1 & 2)
As per IS: 3347 Part I (Section
1 & 2)
As per IS: 3347 Part I (Section
1 & 2)
2.2 LV bushing
2.3 Neutral bushing
3. Rated
impulse
voltage in kV rms.
withstand
3.1 HV bushing
4. One-minute power frequency
withstand test in kV (rms.)
4.1 HV bushing
4.2 LV bushing
95
28
3
4.3 Neutral bushings
5. Minimum Creepage distance in
mm
5.1 HV bushing
5.2 LV bushing
5.3 Neutral
3
350
55
55
30.0 DOCUMENTATION :
30.1 The bidder shall furnish along with the bid the dimensional drawings of the
items offered indicating all the fittings.
30.2 Dimensional tolerances
30.3 Weight of individual components and total weight.
30.4 An outline drawing front (both primary and secondary sides) and end elevation
and plan of the tank and terminal gear, wherein the principal dimensions shall
be given.
30.5 Typical general arrangement drawing of the windings with the details of the
insulation at each point and core construction of transformer.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
30.6 Typical general arrangement drawing showing both primary and secondary
sides and end-elevation and plan of the transformer.
31.0 GUARANTEE:
31.1 The manufacturers of the transformers shall provide a guarantee of sixty (60)
months from the date of commissioning and handover to APDCL.
31.2 In case of failure within the guarantee period the APDCL will immediately
inform the supplier who shall take back the failed DTR within 15 days from the
date of intimation at his own cost and replace/repair the transformer within
thirty (30) days of date of intimation with a roll over guarantee.
31.3 The outage period i.e. period from the date of failure till unit is
repaired/replaced shall not be counted for arriving at the guarantee period.
31.4 In the event of supplier‘s inability to adhere to the aforesaid provision, suitable
penal action will be taken against the supplier which may inter alia include
blacklisting of the firm for future business with the APDCL for a certain period.
32.0 SCHEDULES:
32.1 The bidder shall fill in the following schedule which will be part of the offer. If
the schedule are not submitted duly filled in with the offer, the offer shall be
liable for rejection.
Schedule – A
:
Guaranteed Technical Particulars
Schedule – B
:
Schedule of Deviations
33.0 DEVIATIONS:
33.1 The bidders are not allowed to deviate from the principal requirements of the
Specifications. However, the bidder is required to submit with his bid in the
relevant schedule a detailed list of deviations without any ambiguity. In the
absence of a deviation list in the deviation schedule, it is understood that such
bid conforms to the bid specifications and no post-bid negotiations shall take
place in this regard.
33.2 The discrepancies, if any, between the specification and the catalogues
and/or literatures submitted as part of the offer by the bidders, shall not be
considered and representations in this regard shall not be entertained.
33.3 If it is observed that there are deviations in the offer in guaranteed technical
particulars other than those specified in the deviation schedules then such
deviations shall be treated as deviations.
33.4 All the schedules shall be prepared by vendor and are to be enclosed with the
bid.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
SCHEDULE - A
GUARANTEED TECHNICAL AND OTHER
PARTICULARS –DISTRIBUTION TRANSFORMERS
(To be filled in by Bidder and shall be furnished with the Technical Bid)
Sl.
No
Description
1.
2.
3.
4.
1Name of the Manufacturer
2Installation [indoor/outdoor]
3Reference standards
4Continuous Ratings
a)
b)
c
i
ii
d
i
ii
e
5.
6.
7.
8.
9.
10.
Type of cooling
Rating [KVA]
Rated voltage
HV [KV rms.]
LV [KV-rms.]
Highest system voltage
HV [KV rms.]
LV [KV-rms.]
Rated frequency with ±%
variation
f
Number of phases
g Current at rated full load
i
HV [Amps]
ii LV [Amps]
5Connections
HV
LV
6Connection symbol and vector group
7Temperature rise
a Temperature rise of oil above
reference
peak
ambient
temperature
b Temperature rise of winding
above reference peak ambient
temperature
c Temperature gradients between
windings & oil.
d Limit of Hot spot temperature for
which
the
Transformer
is
designed [°C]
8i
No load loss at rated voltage and
frequency [WATT]
9Load loss at rated output, rated
frequency, corrected for 75 °C
winding temperature at:- [Copper
loss] (WATT)
1Total losses
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
0
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
Maximum losses at 100% loading at
750C
Maximum losses at 50% loading at
750C
1Positive sequence impedance on
1rated KVA base at rated current and
frequency at 75°Centigrade winding
temperature. (%)
1% reactance at rated KVA base at
2rated
current and rated frequency (%)
1% resistance at rated KVA base at
3rated current and rated frequency [%]
1% Impedance at rated KVA base at
4rated
current and rated frequency [%]
1a Polarisation index i.e. ratio of
5
Megger values at 600 secs to 60
secs, (H.V. to E, L.V. to E, &
H.V.to L.V.). Measurement by 1.0
kV motorised megger.
b Insulation Resistance in MΩ
(At temp ……….0C)
In Between
H.V - E
L.V. - E
H.V – L.V.
PI
HV – E :
LV – E :
HV – LV :
c
Regulation at full load and 75°C
winding temperature expressed
as a percentage of normal
voltage [%]
1Efficiency at 75°C winding
Unity power
6temperature as derived from
factor
guaranteed loss figures and at
a At full load [%]
b At ¾ load [%]
c At ½ load [%]
1i
Maximum efficiency [%]
7ii
Load at which maximum
efficiency occurs[% of full load]
1Short time thermal rating of
8i
HV winding in KA and duration in
seconds
ii LV winding in KA and duration in
seconds
1Permissible over loading:9a HV winding
b LV winding
2Terminal arrangement
0a High voltage [HV]
b Low voltage (LV)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
0.8 Power
factor
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
24.
2Insulating and cooling medium
1
2Test voltage
2
c
25.
Neutral
HV
LV
i
26.
27.
28.
Lightning impulse withstand test
voltage [KVP]
ii Power frequency withstand test
voltage [dry and wet][for 1
minute] [KV-rms.]
2External
short circuit withstand
3capacity
[MVA]
and
duration
[seconds]
2Over-fluxing withstand capability of
4the
Transformer
2DETAILS OF CORE
5a Type of core construction
b Type of corner joints of the core
c Maximum flux density at
i
Rated voltage [11/0.4 KV] & rated
frequency 50 Hz][in Tesla]
d No load current, no load loss and No load No Load No
no load power factor at normal current
Loss
PF
ratio
and
frequency
[Amp/KW/p.f.]
i
10 percent of rated voltage
ii 25 percent of rated voltage
iii 50 percent of rated voltage
iv 85 percent of rated voltage
v 100 percent of rated voltage
vi 105 percent of rated voltage
vii 110 percent of rated voltage
vii 112.5 percent of rated voltage
i
ix 115 percent of rated voltage
x 120 percent of rated voltage
xi 121 percent of rated voltage
xii 125 percent of rated voltage
e Core laminations:i
Material of core lamination
[M4/HIB/AM]
ii Grade of core laminations
iii Thickness of core lamination
[mm]
iv Specific loss [watt/Kg.] at rated
voltage and rated frequency
v Specific loss [watt/Kg.] at highest
system voltage and lowest
system frequency
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Load
Technical specification
Sl.
No
Description
vi
vii
vii
i
ix
x
f
i
ii
iii
iv
v
vi
vii
vii
i
ix
x
xi
xii
xii
i
xi
v
x
v
g
29.
Whether specific core loss graph
[flux
density
vs.
watt/Kg.
submitted
VA/Kg at rated voltage and rated
frequency
VA/Kg. at highest system voltage
and lowest system frequency
Whether VA/Kg. Vs. flux density
graph Submitted
Insulation of core laminations
CORE ASSEMBLY:Core diameter [mm]
Core window height [mm]
Core leg centre [mm]
Gross core cross-sectional area
[cm²]
Whether details of core widths,
stacks and calculation furnished
as per enclosed annexure
Distance between centers [mm]
Total height of core [mm]
1)
Details of core Clamping
with nos. of core stud.
2)
Material, grade & type
3)
Width
4)
Thickness
5)
Fixing method
Details of top end frame
Details of Bottom end frame
Details of clamp plate [Material,
thickness, Insulation]
Total core weight [kg]
Core loss basing on core loss
graph at operating flux density
[rated
voltage
and
rated
frequency] [kw]
Core stacking factor
Net core area Sq. cm.
Describe location/method of core
grounding
h Details of oil ducts in core if any
i
Peak value of magnetizing Inrush
current (% of HV rated current).
2DETAILS OF WINDINGS.
6a Type of winding
b Material of the winding conductor
c Maximum current density of
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
HV
LV
Conductor
Current density
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
windings [at rated current] and
area [cm²]
[A/cm²]
conductor area
i
HV
ii L.V.
d Whether HV windings are
crossover/ Sectional
e Whether windings are preshrunk?
f
Whether adjustable coil clamps
are provided for H.V. and L.V.
windings?
g Whether steel rings or perma
wood are used for the windings?
If steel rings used, whether these
are split?
h Winding Insulation.
Type & class
i
H.V.
ii LV Winding
i
Insulating material used for
i
H.V.
ii L.V Winding
j
Insulating material used between
i
H.V. and L.V. winding
ii Core and L.V winding
iii H.V. winding and core
iv H.V. to H.V. winding [between
phases]
V Inter coil spacers between HV
sections (mm)
Vi Type of block between HV
sections
Vi Oil duct between
LV to cylinder (mm) :
i
Cylinder to HV (mm) :
k Type of axial coil supports
i
H.V. winding
ii LV winding
l
Type of radial coil supports
i
H.V. winding
ii LV winding
m Maximum allowable torque on
coil clamping HV & LV bolts
n Bare conductor size (mm).
HV :
LV :
o Insulated conductor size (mm).
HV :
LV :
p Number of coil per phase
HV :
LV :
q No. of conductors in parallel
HV :
(Nos.).
LV :
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
r
30.
No. of turns/phase
HV coil :
LV coil :
s Inside diameter (mm).
HV coil :
LV coil :
t
Outside diameter (mm).
HV coil :
LV coil :
u Axial height after shrinkage (mm). HV coil :
LV coil :
v D.C.RESISTANCE
i
L.V winding at 75 ° C (Ohms).
ii HV winding at 75° C (Ohms).
iii Total I²R losses at 75 ° C. (KW).
iv Stray losses including eddy
current losses in winding at 75°C
(KW).
v Any special measures taken to
reduce eddy current losses and
stray losses, mention in details
vi Load losses at 75°C [I²R +
stray].[Watt]
w Details of special arrangement
provided to improve surge
voltage
distribution
in
the
windings
2BUSHINGS.
HV
LV
7
a
i
ii
b
c
i
ii
d
e
f
g
h
i
Make and type
Rated voltage class [KV-rms.]
Rated current [Amps.]
Lightning Impulse withstand test
voltage [1.2/50 micro
second][KVP]
Power frequency withstand test
voltage
Wet for 1 minute [KV-rms]
Dry for 1 minute [KV-rms]
Minimum creepage distance in
mm
Weight of assembled bushing
[Kg.]
Minimum clearance height for
removal of bushing [mm]
Under oil flashover or puncture
impulse voltage [KVP]
Under oil flashover or puncture
power frequency voltage (KVrms).
Phase to earth clearance in air of
live parts at the top of bushings
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Neutral
Technical specification
Sl.
No
Description
31.
2Minimum clearance [mm]
8
32.
33.
In Oil
Betwee Phase
n
to
winding Groun
s
d
Out of Oil
Betwee Phase
n
to
winding Groun
s
d
HV
LV
a Radial clearance between LV and
HV (mm)
b Radial clearance between core to
LV (mm)
c End clearance of HV coil to yoke
(mm)
d End clearance of LV coil to yoke
(mm)
e Gap between yoke to bottom of
tank (mm)
2Weight [Tolerance + 5%]
9[Approximate value is not allowed]
a Core [Kg.]
b Core with clamping [Kg.]
c H.V. winding insulated conductor
[Kg.]
d L.V.winding insulated conductor
[Kg.]
e Coils with insulation [Kg.]
f
Core and winding [Kg]
g Oil required for first filling
[Liter/Kg.]
h Tank and fittings with accessories
[Kg.]
i
Untanking weight [Kg.]
j
Total weight with oil and fittings
[kg.]
3DETAILS OF TANK
0
a
b
c
i
ii
iii
iv
d
i
Material for Transformer tank
Type of tank
Thickness of sheet
[No approximate value to be
mentioned]
Sides [mm]
Bottom [mm]
Cover [mm]
Radiators [mm]
Inside dimensions of main tank
[No approximation in dimensions
to be used]
Length [mm]
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
ii
iii
e
34.
35.
Breadth [mm]
Height [mm]
Outside dimensions of main tank
[No approximation in dimensions
to be used]
i
Length [mm]
ii Breadth [mm]
iii Height [mm]
f
Thickness of spray galvanisation
of tank bottom.
g Vacuum recommended for hot oil
circulation [torr]
h Vacuum to be maintained during
oil filling in Transformer tank [torr]
i
Vacuum to which the tank can be
subjected without distortion [torr]
l
Type and make of pressure relief
device and minimum pressure at
which it operates [Kpa]
3CONSERVATOR
1a Total volume [Liters]
b Volume between the highest and
lowest visible oil levels [Litres]
3OIL QUALITY
2a Governing standard
b
c
d
e
f
g
h
i
i
ii
j
k
l
m
i
ii
o
i
Density in gms/cu-cm
Kinematics viscosity in CST
Inter facial tension at 27°C in N/m
Flash point in °C
Pour point in °C
Acidity [neutralization value] in
mg of KOH/gm
Corrosive sulfur in %
Electric strength [breakdown
voltage]
As received [KV-rms.]
After treatment [KV-rms.]
Dielectric dissipation factor [tan
delta] at 90°C
Saponification value in mg of
KOH/gm
Water content in ppm
Specific resistance
At 90°C [ohm-cm]
At 27 °C [ohm-cm]
Oxidation stability
Neutralization value after
oxidation
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
ii
p
36.
37.
38.
39.
40.
41.
42.
43.
Total sludge after oxidation
Characteristic of oil after ageing
test as per ASTMD-1934
i
Specific resistance at
27°C [ohm-cms]
90°C [ohm-cms]
ii Tan delta
iii Sludge content
iv Neutralization number
v Details of oil preserving
equipment offered
3RADIATORS
3a Overall dimensions lxbxh [mm]
b Total weight with oil [Kg.]
c Total weight without oil [Kg.]
d Thickness of radiator tube [mm]
e Types of mounting
f
Vacuum withstand capability
g Total radiating surface in sq.m
h Type and make of material used
for the radiators
i
Total number of radiators/Banks
for
Transformer and dimensions of
tubes
j
Thickness of hot dip
galvanization of radiators
3APPROXIMATE OVERALL DIMENSIONS
4OF TRANSFORMER
Length [mm]
Breadth [mm]
Height [mm]
3Transformers will be transported with
7oil.
3Types of terminal connectors and
8drawing No
a HV
b LV
3Details of painting, galvanization
9conforms to this Specification
[Yes/No]
4No. of breathers provided [Nos.]
0
4Type of dehydrating agent and
1quantity used for breathers
4Valve sizes and numbers
2a Filter valves- mm-Nos
b
44.
4a
Sampling valves- mm-Nos
Type and make of PRV
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
Description
3b
45.
46.
47.
48.
49.
50.
51.
No. of each type of devices per
transformer
c Min. pressure at which device
operates
4Please enclose the list of accessories
4and fittings, being provided on
transformer. Please confirm, these
are as stipulated in the tender
4Whether the transformer, covered is
5fully type tested and if so, whether
copies of type test certificates,
enclosed with the tender
4What are the arrangements, available
8for jointing the winding. Preference
shall be given to the tenderer using
high-frequency brazing machines. In
case other jointing techniques are
used, adequacy of the same is to be
recorded. Please note that bolted
joints in the winding are not
acceptable. This should be confirmed
here
4Please
confirm that you will
9guarantee
maximum
Impedance
variation between phases within the
limit of 2% only
5a Please
confirm
that
the
0
transformer shall be dried by
vapour/ vacuum-phase drying
method. Please specify level of
dryness
b In case, other methods of drying
are used, the level of dryness, so
achieved should be identical to
that by V/VPD. Adequacy of such
system should be justified
5Whether the Tenderer has got In1House core-cutting facility for cutting
core materials for the transformer
ratings as tendered
5In case SL.50 is not confirmed,
2whether the tenderer is agreed to
follow the procedures, as stipulated at
clause 12.3 of this technical
specification
Signature of Bidder Representative:
Name of Representative:
Designation:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Seal
Date & Place:
Assam Power Distribution Company Ltd
Technical specification
Sl.
NO
Clause NO.
SCHEDULE - B
Technical Deviation Sheet
Deviations
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
TECHNICAL SPECIFICATION OF MICROPROCESSOR BASED
MOULDED CASE CIRCUIT BREAKERS & Box
1. SCOPE
1.1.
1.2.
1.3.
1.4.
1.5.
2.
2.1.
2.2.
2.3.
2.4.
2.5.
2.6.
2.7.
2.8.
This specification covers the general requirement of protection features of MCCB
for satisfactory protection / operation of distribution transformers of rating 16, 25,
63, 100 and 200 kVA. Moulded-Case Circuit Breakers (MCCB) with
microprocessor trip unit shall comply with IEC 60947-1, 60947-2, 60947-3 and
IS 13947-1, 13947-2, 13947-3 standards or with the corresponding standards
applicable in the member countries (VDE 0660, BS 4752, NF EN 60947-1/2):

They shall be of category A with a rated service breaking capacity equal to
the ultimate breaking capacity i.e. Ics =100% Icu. Icu should be 25kA and
above.

They shall have a rated operational voltage of 690 V AC (50±5% Hz).

They shall have a rated impulse withstand voltage of 8KV.

They shall have a rated insulation voltage of 800 V AC (50±5% Hz),

They shall be suitable for isolation, as defined by IEC 60947 –1 and -2, §
7.1.7 for the Over-voltage Category IV for a rated insulation voltage up to
690 V according to IEC 60664-1.
MCCBs shall be designed according to ECO-design complying with ISO 14062
Especially MCCB‘s materials shall be of halogen free type.
MCCBs shall be of 4-pole type.
MCCBs shall be designed for both vertical and horizontal mounting, without any
adverse effect on electrical performance. It shall be possible to supply power
either from the upstream or downstream side.
MCCBs shall provide double insulation between the live power parts and the
front parts where the operator works during normal operation.
Construction, operation, environment
The Microprocessor MCCB should be suitable for operation from -50C to + 700C
and without any de-rating up to 500 C.
MCCB should be supplied along with Extended Rotary handle for interlocking so
that it should be possible to ON/OFF MCCB without opening the panel door.
All poles shall operate simultaneously for circuit breaker opening, closing and
tripping.
MCCBs shall be actuated by a toggle switch for OF/OFF and a push button for
trip.
In order to ensure suitability for isolation complying with IEC 60947-2:

The operating mechanism shall be designed such that the toggle switch
can only be in OFF position (O) if the power contacts are all actually
separated,

In OFF position, the toggle shall indicate the isolation position.

Isolation provided by the double break on the main circuit shall be
preferred.
MCCBs shall be able to receive a device for locking in the ―isolated‖ position,
with padlocks, (8Ø maximum).
MCCBs shall be equipped with a ―push to trip‖ button in front to test operation
and to the opening of the poles.
MCCB rating, ―push to trip‖ button, performances and contact position indication
must be clearly visible and accessible from the front, through the front panel or
the door of the switchboard.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
2.9. MCCB shall be of Current Limiting Type.
2.10. MCCBs shall be equipped with a Microprocessor based Tripping unit. This unit
will trip the circuit-breaker for high value short-circuits currents. The breaking will
be carried out in less than 6ms for short-circuit currents above 8 times the rated
current.
2.11. The electrical life of MCCBs as defined by IEC 60947-2 standard, shall be at
least equal to 8000 electrical operations with number of hourly operation of 120
& above till 100 Kva and 4000 electrical operations with number of hourly
operation of 60 & above from 200 Kva till 630 Kva . Also the Mechanical life of
MCCB should be 25000 operations & above with number of hourly operation of
240 & above till 100 KVA and 20000 & above with number of hourly operation of
120 & above from 200 Kva till 630 KVA.
2.12. The MCCB shall trip in case the environmental conditions of the circuit- breaker
get out of their specified range. However, it will be possible to overrule this
feature.
2.13. Adjustable settings in Microprocessor based MCCB‘s should be through Dip
Switched for precision & in lower steps of 0.04.
2.14. Auxiliaries and accessories
2.14.1. MCCBs shall be designed to enable safe on-site installation of auxiliaries such
as voltage releases (shunt and under-voltage releases) and indication switches
as follows:


They shall be separated from power circuits,
All electrical auxiliaries shall be of the snap-in type and fitted with terminal
blocks,

All auxiliaries shall be common for the entire range.

Auxiliary function and terminals shall be permanently engraved on the
case of the circuit breaker and the auxiliary itself,

The addition of auxiliaries shall not increase the volume of the circuit
breaker.
2.14.2. It shall be possible to equip MCCBs with devices indicating faults without
tripping the circuit breaker.
2.15. The degree of protection of MCCB should be IP56 (with Rotary Handle) and
IP40 with Toggle switch.
2.16. MCCB should have aux switch which indicates ON, OFF & Tripped indications
individually.
3.
Protection functions
3.1. General recommendations
MCCBs shall be equipped with fully interchangeable trip units in order to ensure
the protection against over current, Short-circuit and Ground fault. The trip units
shall be of Microprocessor based.
3.2. Common features
3.2.1. Electronic Trip units shall be adjustable and it shall be possible to fit lead seals to
prevent unauthorised access to the settings.
3.2.2. Electronic trip units shall comply with appendix F of IEC 60947-2 standard
(measurement of RMS current values, electromagnetic compatibility, etc.)
3.2.3. Protection settings shall apply to all circuit breaker poles
3.2.4. The trip units shall not augment overall circuit breaker volume
3.2.5. All electronic components shall withstand temperatures up to 125 °C.
3.3. Electronic trip units
3.3.1. Characteristics
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification


Long time protection (LT)
Selectable Ir threshold settings from 36% to 100 % of the trip unit rating in
the step of 0.04Ir with time delay.
The time delay should be adjustable 3sec/6sec.

3.3.2.
3.3.3.
3.3.4.
3.3.5.
Sl
No.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Short time protection (ST)
Ist threshold shall be adjustable from 1, 5 to 10 times the thermal setting Ir
with time delay.

The time delay should be adjustable 0.1sec/.25sec.

Instantaneous protection
The threshold shall be either adjustable or fixed (starting from 1.0 times In
and up to a value between 10 times In with time delay.
Four-pole devices shall be equipped for neutral protection:
Load monitoring function
The following monitoring functions shall be integral parts of electronic trip units:

2 LEDs for load indication, one lighted above 90 % of Ir, and one lighted
above 105 % of Ir

a test connector shall be installed for checks on electronic and tripping
mechanism operation using an external device.
Thermal memory
In the event of repeated overloads, the electronic trip unit shall optimise
protection of cables and downstream devices by memorising temperature
variations.
Options:
It shall be possible to install all options for the electronic trip unit:

High-threshold earth-fault protection,

Auxiliary contact to indicate the cause of tripping long time, short time,
instantaneous, earth fault if requested.
Particulars
Transformer Capacity (KVA)
16
25
63
100
200
Rated operating current,
frame size Amp (Min.)
Micro Processor MCCB with
Rating
Adjustable overload release
setting
Rated voltage (Volts)
Rated Insulation level
Number of poles
Rated Ultimate breaking
capacity Ics (KA) is 100% of
Ultimate Breaking capacity,
Icu
Rated
service
breaking
capacity ICS (KA) is 100% of
ultimate breaking capacity, Icu
Frequency
Impulse withstand voltage
High voltage withstands
32A
32A
32A
50A
50A
32A
100A
160A
320A
100A
160A
320A
100A
160A
318.8A
690V
1000V
4
690V
1000V
4
690V
1000V
4
690V
1000V
4
690V
1000V
4
10KA
(Min)
10KA
(Min)
25KA
(Min)
25KA
(Min)
25KA
(Min)
For All
50Hz
±3%
8 kV
3 KV
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
50Hz
±3%
8 kV
3 KV
50Hz
±3%
8 kV
3 KV
Assam Power Distribution Company Ltd
50Hz
±3%
8 kV
3 KV
Technical specification
4.
4.1.
4.2.
4.3.
4.4.
5.
5.1.1.
5.1.2.
5.1.3.
5.1.4.
5.1.5.
5.1.6.
5.1.7.
5.1.8.
5.1.9.
5.2.
5.2.1.
5.2.2.
5.3.
5.4.
5.5.
5.5.1.
5.5.2.
voltage for 1 min.
PRINCIPAL PARAMETERS:
MCCBs shall have manually adjustable Current Settings up to range of 40100%.
It should have inverse time characteristics for overload and trip time should be
less than 10 msec.
MCCBs should have finger-proof feature i.e, no live part(s) should be visible of
MCCB.
List of Approved Makes : SIEMENS/ ABB/L&T/Schnieder.
GENERAL TECHNICAL REQUIREMENTS:
The moulded case circuit breaker should be provided with auxiliary switch to
differentiate ON/OFF & tripped indication.
Material used in construction of circuit breaker shall be capable of withstanding
the degree of protection & stress without distortion or failure of any part.
The MCCB shall be supplied complete in all respect with necessary tools, bolts
and other accessories considered necessary by tenderer‘s for satisfactory
operation.
The MCCB shall be completely maintenance free.
All equipment accessories and wiring shall have tropical protection, involving
special treatment of metal and insulation against fungus, insects and corrosion.
The safety clearance of all live parts of the equipments shall be as per relevant
standards.
MCCB should be provided with microprocessor type release for the protection of
the T/F against over loading and short circuit.
The MCCB should be provided with disconnecting functions with positive
isolation features.
The MCCB should be provided with push to trip features also.
OPERATING MECHANISM:
The MCCB shall have an auxiliary switch with on and off & trip indicator.
Microprocessor based type, quick break; quick make (trip free) mechanism
should be provided in the MCCB.
DESIGN AND OPERATING PRINCIPLE:
The design & operating principle of moulded case circuit breaker should be of
current limiting design with fast operating time and low thermal stress with
compact size and independent manual operation.
Moulded case circuit breaker should have the provision like position of switch
different from ON & OFF state to indicate the tripping of MCCB.
TIME/CURRENT CHARACTERISTICS:
The MCCB shall not cause any tripping due to switching current of inductive and
capacitive loads.
The MCCB shall have the following time/current characteristics:
Multiple of normal current setting Tripping time
1.05
More than 12 Hrs
1.20
<= 2 Hrs
1.30
<= 5 Minutes
1.40
<= 2 Minutes
2.50
<= 1 Sec
4.00
,<= 40 m sec
For the time/current characteristic, the reference calibration temperature of the
breaker shall be 50oC. De-rating, if any up to 60oC operating temperature shall
not exceed 10% of the current setting indicated in Para 5.5.1.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
5.6.
5.7.
5.7.1.
5.7.2.
5.7.3.
5.7.4.
5.7.5.
5.7.6.
5.8.
5.9.
5.9.1.
5.9.2.
5.10.
5.11.
TEMEPRATURE RISE LIMIT:
The temperature rise on any part of equipment shall not exceed the maximum
temperature rise limit specified in relevant ISS over an ambient temperature of
o
40 C.
MCCB BOX
A tentative drawing of box showing general arrangement is enclosed as
reference (Annexure-VII) as an integral part of the transformer which shall have
to cover the LV side bushings.. The MCCB should be connected by insulated
copper bus bar/ copper cable of appropriate size from the LV side bushings of
the transformer and from MCCB to outgoing cable connector interface points.
The transformer manufacturer has to design the box in such a way that the
APDCL‘s workman will simply connect the outgoing cable at the connectors
provided by the manufacturer.
Cable size for different rating of transformer shall be as follows: For 16KVA –
3½-core, 16 sq.mm, 25KVA – 3½-core , 25 sq.mm, 63KVA – 3½-core 90 mm2,
100KVA 1-core, 1x90 mm2 and for 200KVA, 1-core, 2x120 mm2. Accordingly,
the bidder has to submit detail drawing considering the requirements laid above
for accorded of approval from APDCL.
The MS sheet thickness of steel should not be less than 2.5 mm. The painting
should be followed to that of transformer paintings procedure.
The required cable glands and bi-metallic lugs as per cable size described above
shall be supplied by the bidder. The gland plate should be non- magnetic
material of adequate strength with pre-fabricated gland fitting hole.
The MCCB box should be IP 55 grade.
The door of the box should be of pad-lockable type.
ERECTION TOOLS:
Special tools and standard accessories required for assembly and for
maintenance of the MCCB should also form a part of the supply. Necessary list
should be supplied with the tender.
CABLE:
Copper cable of adequate size with ISI mark should be provided in the MCCB.
Bakelite sheet should be used in the moulded case circuit breakers of make
Hyalm, Super Hualm, milliborn or any reputed make. The MCCB should be fixed
in side the metal box on the bakelite sheet. The bakelite sheet should be
provided, for the MCCB, in L.T. Box having the following parameters:S.No. T/F Capacity
Minimum size
Minimum thickness
1.
16 & 25 kVA
150x250mm
4mm
2.
63 & 100 kVA
150x250mm
5mm
3.
200 kVA
250x350mm
6mm
INDICATORS:
The MCCB shall have a set of auxiliary contacts built in for indicating the
healthiness of phases i.e. R,Y, & B. These normally open contacts shall form
part of the signal light circuit. The signal light circuit shall consist of any auxiliary
T/F capable of delivering 4 volt on the secondary side.
RATING PLATE:
MCCB shall be provided with a rating plate marked with but not limited to
following data:i. Manufacturer‘s name, type of MCCB
ii. Serial number
iii.Owners name
iv. Rated voltage
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
v. Rated normal continuous current
vi. Rated insulation level
vii. Rated frequency
viii. Rated short time breaking current with rated duration
ix. Total weight of breaker
6.
TESTS:
6.1. TYPE TESTS:
The equipment offered should be fully type tested as per relevant standards. In
case the equipment of the type and design, offered, has already been type
tested (not later than five years) the Bidder shall furnish for sets of the type test
reports also with the offer. The purchaser reserves the right to demand repetition
of the same all type tests in the presence of Purchaser‘s representative. For this
purpose Bidder may quote unit rates for carrying out each type tests. For any
change in the design/type already type tested viz-a-viz the design/type offered
against the specification the purchaser reserves the right to demand the
repetition of the same without any extra cost. In case the equipment has not
been type tested earlier, the type tests as per relevant standard shall be carried
out by the successful Bidder in the presence of Purchaser representative.
The type test report(s) submitted by the bidder/ supplier from Govt. approved
NABL accredited laboratory shall only be acceptable for participation of the
bidder in the procurement/ empanelment process. In case NABL accredited
laboratory happens to be that of manufacturer itself, added precaution shall be
taken to get type test and other tests witnessed in the laboratory by APDCL
representative at the time of acceptance of material.
6.2. ACCEPTANCE AND ROUTINE TESTS:
6.2.1. All acceptance and routine tests as per relevant ISS shall be carried out by the
bidder in the presence of Purchaser representative.
6.2.2. ADDITIONAL TEST:
The purchaser reserves the right to carry out any other type tests of a
reasonable nature at the works of the supplier/laboratory or at any other
recognized laboratory/research institute in addition to the above mentioned type,
acceptance and routine tests at the cost of the purchaser to satisfy that the
material complies with the intents of this specification and also if there is any
dispute regarding quality of the equipment.
7.
INSPECTION
7.1. The inspection may be carried out by the authorized representative of purchaser
at any stage of manufacture. The successful bidder shall grant free access to the
purchaser‘s representative at a reasonable time when the work is in progress.
Inspection and acceptance of any equipment under this specification by the
purchaser shall not relieve the bidder of his obligation of furnishing equipment in
accordance with the specification and shall not prevent subsequent rejection, if
the equipment is found to be defective. The Bidder shall keep the purchaser
informed in advance about the manufacturing programme so that arrangement
can be made for inspection.
7.2. The purchaser reserves the right to insist for witnessing the acceptance/routine
testing of the bought out items.
7.3. No material shall be dispatched by manufacture unless the material has been
satisfactorily inspected tested and further dispatch authorized by purchaser.
8.
LIST OF DRAWINGS AND DOCUMENTS:
The bidder shall furnish four sets of relevant descriptive and illustrative published
literature pamphlets and the following drawings for preliminary study along with
the offer.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
a). General outline drawings showing dimensions and shipping weights, quantity of
insulating media etc.
b). Sectional views showing the general constructional features of the circuit breaker
including operating mechanism, arcing chambers, contacts with lifting
dimensions for maintenance etc.
c). Schematic diagrams of MCCB offered for control supervision and reclosing.
9.
PACKING AND FORWARDING:
The equipment shall be packed in suitable creates so as to withstand handling
delivery transit. The bidder shall be responsible for any damage to the equipment
during transit, due to improper and inadequate packing and handling. The easily
damageable material shall be carefully packed and marked with the appropriate
cautions symbols. Wherever, necessary proper arrangement for lighting such as
lifting hooks etc. shall be provided. Any material found short inside the packing
cases shall be supplied y the bidder without any extra cost.
10.
GUARANTEE / WARRANTEE
The supplier shall be responsible to replace, free of cost, with no transportation
or insurance cost to the Purchaser, up to destination, the whole or any part of the
material which in normal and proper use proves the defective in quality or
workmanship, subject to the condition that the defect is noticed within 60 (sixty)
months from the date of receipt of material in stores OR 54 (fifty four) months
from the date of commissioning whichever period may expire earlier. The
consignee or any other officer of APDCL actually using the material will give
prompt notice of each such defect to the supplier. The replacement shall be
effected by the supplier within a reasonable time, but not, in any case, exceeding
30 (thirty) days. The supplier shall, also, arrange to remove the defective within a
reasonable period, but not exceeding 30 (thirty) days from the date of issue of
notice in respect thereof, failing which, the purchaser reserve the right to dispose
of defective material in any manner considered fit by him (Purchaser), at the sole
risk and cost of the supplier. Any sale proceeds of the defective material after
meeting the expenses incurred on its custody, disposal handling etc., shall
however be credited to the supplier‘s account and set off against any outstanding
dues of the purchaser against the supplier.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
11.
GUARNTEED TECHNICAL PARTICULARS
GUARANTED TECHNICAL PARTICULARS OF MICROPROCESSOR BASED
MCCB TO BE USED UP TO 200 kVA DISTRIBUTION TRANSFORMERS
Sl No
Descriptoin
Technical Particulars
A.
Microprocessor Based MCCB Specification
1.
Moulded case Circuit Breaker
Microprocessor Based (MCCB) approved
makes.
2.
Type of Microprocessor Based MCCB,
3.
Standards to which confirms to for
a). Accuracy
b). Protection/safety
4.
Rated Operating Current, Frame size Amp.
5.
Rated voltage, volts
6.
Rated Insulation Level
7.
Fixed overload release setting (Amp.)
8.
Number of Poles
9.
Rated Ultimate Breaking capacity, Icu (KA)
as per IS: 13947/1933.
10. Rated service breaking capacity Icu (KA) is
75% of Ultimate Breaking capacity, Icu.
11. Power factor for short circuit (Max.)
12. Utilization capacity
13. Power loss & mill volt drop values
14. Protection against over load.
15. Impulse withstand voltage.
16. High voltage withstands voltage.
17. Type of mechanism
18. Design & Operating Principle.
19. Whether time-current characteristics is as
per specifications with limit of derating with
temperature rise.
20. Whether the MCCB is having disconnecting
functions with positive isolation features.
21. Whether the Microprocessor Based MCCB
is having flexible mounting with line-load
reversibility features i.e. no change in rating
and breaking capacity of MCCB when
mounted in different orientations and with
line and load connections changed.
22. Whether the Microprocessor Based MCCB
is having push-to-trip feature.
23. Whether the Microprocessor Based MCCB
is having provision like position of switch
different from ON & OFF state to indicate
tripping of MCCB.
24. Weight of the Microprocessor based
MCCB.
25. Whether samples submitted with offer as
specified.
26. Instructions and operating manual with
sample
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
27.
B.
1.
2.
3.
4.
5.
C.
1.
2.
3.
4.
5.
6.
D.
1.
2.
3.
4.
E.
1.
2.
3.
4.
5.
6.
7.
8.
F.
1.
2.
3.
Mfg. Type Test Report.
CABLE Specification
Copper cable approved makes
Copper cable size per phases
Copper cable size of Neutral
Total copper cable required.
Copper cable length
THIMBLE/LUGS SPECIFICATION
Makes.
Metal to be use
Size for phases
Size for Neutral.
Total no. of thimble/lugs to be fitted
a.
mm
b.
mm
Crimping of thimble/Lugs
BAKELITE SHEET Specification
Bakelite Sheet approved Makes.
Fixing of Microprocessor based MCCB
inside of Box.
Bakelite sheet Thickness.
Bakelite Sheet Size.
BOX Specification
Size of box and fixing arrangement with
box.
Box inside look and outside look as per
design.
MS sheet thickness
Air ventilation provided in Box.
IP grade
Microprocessor Based MCCB On/Off
switch window to be provided with window
shed.
Danger Plate with operating instructions.
Rubber glands.
LED Indicators Specification
LED indicators approved Makes.
Colour & Nos. of indicators to be provided.
Mounting of indicators.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
ANNEXURE – I
MAXIMUM FLUX DENSITY AND CORE WEIGHT
CALCULATION
(To be filled in by Bidder and shall be furnished with the Technical Bid)
Step No
Width of steps [mm]
Stack Thickness
Gross Iron Area
[mm]
[mm²]
1
2
3
4
5
6
7
8
9
10
---------------Bmax = E/(4.44 x f x Ai x N)
Where E = L.V. winding phase voltage / phase
f = Rated frequency = 50 HZ.
Bmax. = Maximum flux density in Tesla.
Ai = Net iron area in sq.m = Gross iron area x stacking factor in sq.m
N = Number of L.V.winding, turns/phase
Stacking Factor = 0.97 maximum
Core weight calculation:Core dia [in mm] =
Window height [in mm] =
Limb center [in mm] =
Weight of core = [3 x window height + 4 x limb centre + 2 x max. width] x Net
iron area x Density of core
NB: - 1 Specific loss vs. flux density graph for the type of core lamination to be used
has to be furnished.
2. VA/Kg. Vs flux density graph for the core lamination to be used has to be
furnished.
3. Any other factor assumed for above calculation to be explained with reasons.
N.B.:- The bidder may use its own method of calculation towards determination of
maximum flux density and weight of the core. But the same shall be supported
with proper explanation and justification.
Place:
Date:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Signature of Tenderer
with seal of Company.
Assam Power Distribution Company Ltd
Technical specification
ANNEXURE – II
DETAILS OF LOSS CALCULATION
(To be filled in by Bidder and shall be furnished with the Technical Bid)
Sl.
No
1.
Particulars
Values
Flux density at
(i) 12/1.1 kV & 50 Hz, Tesla
(ii) 11/0.433 kV & 48.5 Hz, Tesla
2.
Core Data
(i) Core weight in Kg.
(ii) Gross core area [mm²]
(iii) Stacking factor.
(iv) Net core iron area [mm²] [ii x iii]
3.
Specific losses [W/Kg.]
(i) At maximum flux density corresponding to 12/1.1 KV
and 48.5 HZ.
(ii) At maximum flux density corresponding to 11/0.433
KV and 50Hz.
4.
Volt ampere/Kg
(i) At maximum flux density corresponding to 12/1.1 KV
and 48.5 HZ.
(ii) At maximum flux density corresponding to 11/0.433
KV and 50Hz.
5.
Calculated/guaranteed iron loss in KW at:
(i) Rated voltage and rated frequency
(ii) Rated voltage and rated frequency
6.
Current density [A/Sq. mm] for
(i) HV
(ii) LV
7.
Conductor size [in mm²]
(i) HV winding
a) Bare
b) Insulated
c) No of conductors in parallel
(ii) LV winding
a) Bare
b) Insulated
c) No of conductors in parallel
8.
Copper weight
(i) H.V. windings
(ii) LV windings
(iii) Total copper weight [i]+[ii]
9.
10.
11.
12.
13.
14.
L.V. winding resistance in ohms at 75°C/Phase.
H.V. winding resistance in ohms at 75°C/Phase.
Stray losses and eddy current losses [in KW] at 75°C
Resistively of copper to be used for winding
I²R loss at 75°C
Calculated guaranteed copper losses [in KW] at 75°C
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Sl.
No
15.
Particulars
Values
[I²R loss + stray losses]
Computed/guaranteed total loss in KW at rated voltage
and rated frequency
[Copper loss + Iron loss]
NB: - 1 Approximate values in weight and losses etc. are not allowed.
2 Tolerance of + 5% in weights may be quoted without any approximation
Place:
Date
Bidder‘s name:
Signature, designation, seal
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
Annexure - III
QUALITY ASSURANCE PLAN
Manufacturer should submit for purchaser‘s approval a quality assurance plan in line
with this with this document.
Abbreviations:
PS
Plant Standard/ Process Specification.
TR
Test Report
IS
Indian/International Standards
AD
Approved Document such as Drawing, Purchase Order
V
verified by
P
Performed by
W
Witnessed by
H
Hold by Purchaser
1
Purchaser
2
Manufacturer
3
External laboratory
4
Sub vendor QC
Notes:
1. Minor: The characteristic of a component, process or operation whose
failure neither materially reduce the usability of the product in operation,
nor does it affect the aesthetic aspects.
2. Major : The characteristic of a component, process or operation whose
failure may cause operation failure which cannot be readily corrected, at
site cause substandard performance, increase erection and maintenance
cost, reduce life or seriously affect aesthetics.
3. Critical : The characteristic of a component, process or operation failure
of which will will surely cause operating failure or intermittent troubles
which is difficult to rectify at site or render the unit unfit for use or safety
hazards.
4. ―Failure‖ of a characteristics means failure to meet the ‗accepted norms‘.
5. Sampling : generally sampling will be done in accordance with IS:2500.
Sampling be as under
If 100% ―Witness‖ of tests is carried out by Prime Supplier, Customer will
witness on sample basis or if 100% ―Witness‖ of tests is carried out by Sub
Vendor, Manufacture will witness on sample basis.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Technical specification
QUALITY ASSURANCE PLAN FOR DISTRIBUTION TRANSFORMERS
Sl
No
Component
&
Operations
1
2
RAW Materials
1
CRGO
Aluminium /Copper
Wire Rod
3
4
Kraft Paper
Epoxy dotted Kraft
paper
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Dimensions
Specific loss
Chemical analysis
Surface insulation
resistance
Transit damage
Stacking factor
Tensile strength
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
100%
100%
Sample/lot
100%
Major
Major
Major
Visual
Measurement
Measurement
100%
100%
100%
Elongation
Dimensions
Transit damages
Cracks & twists
Resistivity
Chemical analysis
Major
Major
Major
Major
Major
Major
Measurement
Measurement
Visual
Visual
Measurement
Measurement
Transit damages & Packing
Conditions
Dimensions
Density
Tensile strength
Elongation
Moisture content
Ash content
Dielectric strength
Transit damages & Packing
Conditions
Dimensions
Density
Tensile strength
Elongation
Major
Visual
100%
100%
100%
100%
100%
One
sample/consi
gnment
100%
Major
Major
Major
Major
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Visual
10% of lot
100%
100%
100%
100%
100%
2 samples/lot
100%
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Moisture content
Ash content
Major
Major
Measurement
Measurement
10% of lot
100%
100%
One sample/
consignment
100%
100%
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
334
Technical specification
Sl
No
1
5
Component
&
Operations
2
Insulating Oil
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Dielectric strength
Thickness of resin coating
Appearance
Major
Major
Major
Measurement
Measurement
Measurement
Major
Major
Major
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Test
2 samples/lot
samples/lot
Sample from
each tanker
- do - do - do - do - do - do - do -
Major
Major
Measurement
Measurement
- do - do -
Major
Measurement
- do -
Major
Major
Major
Measurement
Test
Measurement
Major
Major
Major
Major
Major
Major
Major
Major
Major
Measurement
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
- do - do Sample from
each tanker
- do 10% of lot
10% of lot
Sample/lot
Sample/lot
Measurement
Measurement
Measurement
Measurement
Major
Major
Major
Major
Major
Major
Major
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
10% of lot
10% of lot
Sample/lot
Sample/lot
Sample/lot
Sample/lot
Sample/lot
0
6
Insulating Press
Board
7
Perma Wood
Density at 27 C
0
Viscosity at 27 C
0
Interfacial tension at 27 C
Flash point
Pour Point
Total acidity
Corrosion Sulphur copper
0
strip.19 hours @ at 140 C
BDV
Dielectric dissipation factor
0
@ at 140 C
Specific resistance
0
0
at 27 C & at 90 C
Oxidation stability
Accelerated ageing test
Presence of oxidation
inhibitor
Water content
Finish Appearance
Dimensions
Density
Tensile strength
BDV
Ash content
Moisture content
Conductivity of aqueous
extracts
Finish Appearance
Dimensions
Density
Tensile strength
Cross breaking strength
Impact strength
Compressive strength
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
335
Technical specification
Sl
No
1
Component
&
Operations
2
8
Paper covered
conductor
9
Enamel Covered
Conductor
10
MS material (Plates,
Flats, Angles &
Channels
11
Hard Ware
12
Gaskets
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Shear strength
Moisture content
Oil absorption
Finish Appearance
Dimensions
Resistivity
Tensile strength
Elongation
Covering thickness
Finish Appearance
Dimensions
Resistivity
Tensile strength
Elongation
Covering thickness
Flexibility Test
Adherence
Heat Shock
Hardness
Solvent Resistance
BDV
Cut-through Test
Finish Appearance
Dimension
Hardness
Chemical composition
Tensile strength
Yield strength
Elongation
Bend test
Dimensions
Finish Appearance
Finish appearance
Dimensions
Compressibility
Tensile Strength
Recovery%
Oil immersion test
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Measurement
Measurement
Measurement
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Test
Test
Test
Measurement
Test
Measurement
Test
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Test
Measurement
Visual
Visual
Measurement
Measurement
Measurement
Measurement
Measurement
Sample/lot
Sample/lot
Sample/lot
100%
Each bobbin
Sample/lot
Sample/lot
Sample/lot
Each bobbin
Each bobbin
Each bobbin
Sample/lot
Sample/lot
10%
Each bobbin
40%
40%
40%
40%
Sample/lot
40%
Sample/lot
100%
2% of lot
Sample/lot
Sample/lot
Sample/lot
Sample/lot
Sample/lot
Sample/lot
Sampling
Sampling
5%
5%
Sample/lot
Sample/lot
Sample/lot
Sample/lot
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
336
Technical specification
Sl
No
1
Component
&
Operations
2
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Compression test at 110 C
Major
Measurement
Sample/lot
Finish appearance
Dimensions
Power frequency withstand
test
Porasity test
Temperature cycle test
Finish appearance
Dimensions
Finish appearance
Major
Major
Major
Visual
Measurement
Test
100%
10% of lot
5 Nos/lot
Major
Major
Major
Major
Major
Test
Test
Visual
Measurement
Visual
5 Nos/lot
5 Nos/lot
5% of lot
5% of lot
2% of lot
Thickness of coating
Appearance
Viscosity
Major
Major
Major
Measurement
Visual
Measurement
2% of lot
Sample/lot
Sample/lot
Appearance
Shade
Viscosity
Shade
Scratch Hardness
Drying time
Appearance
Viscosity
Shade
Drying time
Finish
Scratch Hardness
Flexibility & adhesion
Shade
Pencil hardness
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Major
Visual
Visual
Measurement
Visual
Test
Measurement
Visual
Measurement
Visual
Measurement
Visual
Test
Test
Visual
Test
100%
100%
Sample/lot
100%
Sample/lot
Sample/lot
100%
Sample/lot
100%
Sample/lot
100%
Sample/lot
Sample/lot
100%
Sample/lot
Cross hatch adhesion
Curing cycle
Finish appearance
Dimensions
Chemical compositions
Finish appearance
Major
Major
Major
Major
Major
Major
Test
Measurement
Visual
Measurement
Test
Visual
Sample/lot
Sample/lot
100%
5% of lot
1 no/ lot
10%
0
13
Bushing
a) Porcelain
b) Metal Parts
14
Plating/Galvanizing/P
hosphating
15
Epoxy resin
16
Paints
a) Primer
b) Hot oil Resistance
paint
C) Polyurathane paint
d) Thermo setting
Powder Paint
17
HV & LV Connectors
18
Oil level gauge
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
337
Technical specification
Sl
No
1
19
1
Component
&
Operations
2
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Dimensions
Gel weight
Gel colour
Dimensions
MANUFACTURING PROCESS & ASSEMBLY
Transformer tank,
Check of raw materials
Conservator &
Cutting of material as per
accessories
given drawing
Finish dimensions &
completeness as per
drawing
Conservator tank and tube
dimensions
Finish of weld
Finish of material after gas
cutting and welding
Leak test
Vacuum test
Major
Major
Major
Major
Measurement
Measurement
Visual
Measurement
10%
10%
100%
10%
Major
Major
Visual
Measurement
100%
Sampling
Major
Measurement
Sampling
Major
Measurement
Sampling
Major
Major
Visual
Visual
Sampling
100%
Major
Major
Test
Surface finish prior to pain
application
Check of inside painting
Application of primer
coating
Application of first coat of
paint
Application of finish coat of
paint
Paint thickness
Adhesion
Hardness
Check of raw materials
Dimensions
Weld finish
Surface preparations
Painting
Major
Test
100%
One/each
rating
100%
Major
Major
Visual
Visual
100%
100%
Major
Visual
100%
Major
Visual
100%
Major
Major
Major
Major
Major
Major
Major
Major
Measurement
Test
Test
Visual
Measurement
Visual
Visual
Visual
100%
10%
10%
100%
Sampling
Sampling
100%
100%
Width
Thickness
Major
Major
Measurement
Measurement
Sampling
Sampling
Silicagel Breather
2
Frames & Channels
welding
3
Core assembly
a) Core cutting
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
338
Technical specification
Sl
No
1
Component
&
Operations
2
b) Core annealing
c) Core assembly
4
5
6
7
Winding
Insulation
components
Core & Coil assembly
Drying of core coil
assembly
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Length
Burr
Angle of cutting
Temperature & speed
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Formation of core section
Core dia
Stack thickness
Leg length
Window width
Core weight
Bindings of limbs
Assembly of frame
structures
Pre-core losses
Conductor size
Forma dia
Coil dimensions
(ID,OD,AH,RD)
Insulation arrangement
Turns arrangements
Transposition
Finishing & lead position
Dimensions
Finishing
Dimensions
Axial & Radial insulation
arrangements
Electrical clearances
Yoke filling
Position of lead out
HV & LV Connections
Insulation and Finishing of
brazed/crimped joints
Ratio test
Temperature
Time duration
Insulation Resistance
Major
Major
Major
Major
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Measurement
Measurement
Visual
Visual
Sampling
Sampling
Sampling
Every one
hour
100%
100%
100%
100%
100%
100%
100%
100%
Major
Major
Major
Major
Measurement
Measurement
Measurement
Measurement
Sampling
100%
100%
100%
Major
Major
Major
Major
Major
Major
Major
Major
Visual
Visual
Visual
Visual
Measurement
Visual
Measurement
Measurement
100%
100%
100%
100%
Sampling
100%
100%
100%
Major
Major
Major
Major
Major
Measurement
Visual
Visual
Visual
Visual
100%
100%
100%
100%
100%
Major
Major
Major
Major
Test
Measurement
Measurement
Measurement
100%
100%
100%
100%
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Format
of
Record
9
Agency
V
P
W
10
Remarks
H
11
339
Technical specification
Sl
No
1
8
Component
&
Operations
2
Characteristics
Class
Type of Check
Quantum
of Check
Reference
Document
Acceptance
Norms
3
4
5
6
7
8
Format
of
Record
9
Agency
Tanking & Oil filling
under vacuum
Clamping of CCA
Job locking
Completeness
Dimensions
Electrical clearances
Vacuum
Oil temperature
Fixing of accessories and
fittings as per drawing
Leak proof ness
Major
Major
Major
Major
Major
Major
Major
Major
Visual
Mechanical
Visual
Measurement
Measurement
Measurement
Measurement
Visual
100%
100%
100%
100%
100%
100%
100%
100%
Major
Pressure test
Sampling
a. Winding Resistance
b. Voltage Ratio & Voltage
Vector Relationship
c. Load loss and Impedance
voltage measurement
d. No load loss & No load
Current
e. Neutral current
measurement
f. Insulation resistance
g. Induced Over Voltage
Test
h. Separate source voltage
withstand test
i. Magnetic balance test
a. Short Circuit Test
Critical
Critical
Measurement
Measurement
100%
100%
IS : 2026
IS : 2026
IS : 2026
IS : 2026
TC
TC
1
1
2
2
1
1
Critical
Measurement
100%
IS : 2026
IS : 2026
TC
1
2
1
Critical
Measurement
100%
IS : 2026
IS : 2026
TC
1
2
1
Critical
Measurement
100%
1
2
1
Measurement
Measurement
100%
100%
CBIP
Manual
IS : 2026
IS : 2026
TC
Critical
Critical
CBIP
Manual
IS : 2026
IS : 2026
TC
TC
1
1
2
2
1
1
Critical
Measurement
100%
IS : 2026
IS : 2026
TC
1
2
1
Critical
Critical
Measurement
Measurement
TC
1
IS 2026
IS 2026
2
3
1
1
1
b. Temperature Rise Test
Critical
Measurement
IS 2026
IS 2026
2
1
1
c. Lightining Impulse
Voltage Test
d. Vacuum Test
Critical
Measurement
IS 2026
IS 2026
3
1
1
Critical
Measurement
IS 1180
IS 1180
2
1
1
e. Pressure Test
Critical
Measurement
Sampling
One/Each
rating
One/Each
rating
One/Each
rating
One/Each
rating
One/Each
rating
IS 1180
IS 1180
2
1
1
V
P
W
10
Remarks
H
11
INSPECTION TESTING
2
TYPE TEST
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
340
Technical specification
Annexure – IV
PROFORMA FOR STAGE INSPECTION OF
DISTRIBUTION TRANSFORMER
(A) GENERAL INFORMATION
1. Name of
firm:
M/s.
2. Order No and Date:
3. Rating wise quantity offered:
4. Details of offer
a)
Rating
b) Quantity
c) Serial
Numbers
5. Details of last stage
inspected lot:
a) Total quantity inspected
b) Serial
Numbers
c) Date of stage inspection
d) Quantity offered for
final inspection of
(a)
above with date.
(B) Availability of material for offered quantity:
Details to be filled in
(C) Position of manufacturing stage of the offered quantity
a) Complete tank assembly
b) Core and coil assembly
ready
c) Core assembled
d) Coils ready for assembly
(i) HV coils
(ii) LV coils
Note: (i) A quantity of more than 100 Nos shall not be entertained
for stage inspection.
(ii) The stage inspection shall be carried out in
case:(a) At least 25% quantity offered has been
tanked and
(b) Core coil assembly of further at least 30% of the quantity
offered
has been
completed.
(iii) Quantity offered for stage inspection should be offered for final inspection
within 15 days from the date of issuance of clearance for stage
inspection,
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical specification
otherwise stage inspection already cleared shall be liable for
cancellation.
Sl
No
Particulars
(D)
Inspection of Core
(i) Core Material
(1) Manufacturer's Characteristic
Certificate in respect of grade of
lamination used. (Please furnish test
certificate)
(2) Remarks regarding rusting and
smoothness of core
(3) Whether laminations used for top
and bottom yoke are in one piece
(II) Core Construction:
(i) No of Steps
(2) Dimension of Steps
Step No
1
2
3
4
5
6
As offered :
W mm
T mm
As found :
W mm
T mm
As
offered
As
observed
Deviations
and Remarks
7
9
11
8
10
12
(3) Core dia (mm)
(4) Total cross section area of core
(5) Effective cross sectional area of
core
(6) Clamping arrangement
(i) Channel Size
(ii) Bolt size and No
(iii) Tie rods size and No.
(iv) Painting
(a) Channels
(b) Tie Rods
(c) Bolts
(7) Whether top yoke is cut for LV
connection
(8) If yes, at 7 above, whether
Reinforcement is done.
(9) Size support channels provided
for core base and bottom yoke (
Single piece of channels are only
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
342
Technical specification
acceptable)
(10) Thickness of insulation provided
between core base and support
channel
(11) Core length (leg center to leg
center)
(12) Window height
(13) Core height
(14) Core weight only (without
channels etc)
(E)
INSPECTION OF WINDING
(I) Winding material
(1) Material used for
(a) HV winding
(b) LV winding
(2) Grade of material for
(a) HV winding
(b) LV winding
(3) Test certificate of manufacturer
(enclose copy) for winding material
of:
(a) HV
(b) LV
(II) CONSTRUCTIONAL DETAIL
(1) Size of cross sectional area of
conductor for:
(a) HV winding
(b) LV winding
(2) Type of insulation for conductor
of:
(a) HV winding
(b) LV winding
(3) Diameter of wire used for delta
formation (MM)
(4) Diameter of coils in
(a) LV winding
i) Internal dia (mm)
ii) Outer dia (mm)
(b) HV winding
i) Internal dia (mm)
ii) Outer dia (mm)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
343
Technical specification
(5) Current Density of winding
material used for:
(a) HV
(b) LV
(6) Whether neutral formation on top
(7) HV Coils/Phase
a) Number
b) Turns/Coil
c) Total turns
(8) LV Coils/Phase
a) Number
b) Turns/Coil
c) Total turns
(9) Method of HV Coil Joints
(10) Total weight of coils of
(a) LV winding (kg)
(b) HV winding (kg)
(F)
INSULATION MATERIALS
(I) MATERIAL
1) Craft paper
a) Make
b) Thickness
c) Test Certificate of manufacturer
(enclose copy)
2) Press Board
a) Make
b) Thickness
c) Test Certificate of manufacturer
(enclose copy)
3) Material used for top and bottom
yoke and insulation
(II) Type and thickness of material
used (mm)
a) Between Core and LV
b) Spacers
c) Inter layer
d) Between HV and LV winding
e) Between phases
f) End insulation
(G)
CLEARANCES : (mm)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
(I) Related to core and windings
2) Between HV and LV (Radial)
3) (i) Phase to Phase between
HV conductor
(ii) Whether two Nos. Press Board
each of minimum 1 mm thick
provided to cover the tie rods.
4) Thickness of locking spacers
between LV coils (mm)
5) Axial wedges between HV and LV
coils/ phase (Nos.)
6) No. of radial spacers per phase
between HV coils
7) Size of duct between LV and HV
winding (mm)
(II) Between core - coil assembly
and tank : (mm)
1) Between winding and body:
a) Tank lengthwise
b) Tank breadth wise
2) Clearance between top cover and
top yoke
(H)
TANK:
(I) Constructional details
1) Rectangular shape
2) Thickness of side wall (mm)
3) Thickness of top and bottom plate
(mm)
4) Provision of slopping top cover
towards HV bushing
5) Tank internal dimensions (mm)
a) Length
b) Breadth
c) Height
(i) On LV side
(ii) On HV side
(II) General details:
1) Inside painted by varnish/ oil
corrosion resistant paint (please
specify which type of coating done)
2) Gasket between top cover and
tank
i) Material
ii) Thichness (mm)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
iii) Jointing over laps (mm)
3) Reinforcement of welded angle
(specify size and No. of angle
provided) on side walls of tank.
4) Provision of lifting lugs:
a) Numbers
b) Whether lugs of 8 mm thick MS
Plate provided
c) Whether reinforced by welded
plates edge wise below the lug upto
re-enforcing angle of the tank done
5) Pulling lug of MS Plate
a) Nos
b) Thickness (mm)
c) Whether provided on breadth side
or length side
6) Provision of air release plug
7) Provision of galvanized GI nuts
and bolts with 1 no plain and 1 no
spring washer.
8) Deformation of length wise side
wall of tank when subjected to:
a) Vacuum of (-) 0.7 kg/sq cm for 30
minutes.
b) Pressure of 0.8 kg/sq cm for 30
minutes
(I)
RADIATORS
1. Fin radiators of 1.25 mm thick
sheet
a) Dimension of each fin (LxBxT)
b) Fins per radiator
c) Total number of radiators
2. Varification of manufacturer's test
certificate regarding Heat
Dissipation (excluding top and
bottom) in w/sq m.
3. Verification of position of radiator
with respect to bushing.
(J)
CONSERVATOR :
1. Dimensions (LxD) in mm
2. Volume (cu m)
3. Inside dia of conservator tank
pipe (mm)
4. Whether conservator outlet pipe is
projected approx. 20 mm inside the
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
346
Technical specification
conservator tank.
5. Whether arrangement made so
that oil does not fall on the active
parts.
6. Whether die cast metal oil level
gauge indicator having three
positions at ( - 5, 30 and 98 degree
C) is provided.
7. Whether drain plug and filling hole
with cover is provided.
8. Inner side of the conservator Tank
painted with.
(K)
BREATHER
1. Whether Die cast Aluminium body
breather for silica gel provided.
2. Make
3. Capacity
(L)
TERMINALS
1. Material whether of Brass Rods/
Tinned Copper
a) HV
b) LV
2. Side (dia in mm)
a) HV
b) LV
4. Method of Connection of LV
winding to LV bushing (end of
winding should be crimped with lugs
(Al/Cu) and bolted with bushing
stud).
5. Method of Connection of HV
winding to HV bushing (Copper joint
should be done by using silver
brazing alloy and for Aluminium,
brazing rod or with tubular connector
crimped at three spots).
6. Whether SRBP tube/ insulated
paper used for formation of Delta on
HV.
7. Whether Empire sleeves used on
the portion of HV winding joining to
HV bushing.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
347
Technical specification
8. Whether neutral formation is
covered with cotton tape.
(M)
BUSHING :
1. Whether HV bushings mounted
side wall or Top cover
2. Whether sheet metal pocket used
for mounting bushing (pipes are not
acceptable)
a) HV
b) LV
3. Whether arrangement for studs
for fitting of HV bushing are in
diamond shape (so that Arcing
Horns are placed vertically)
4. Position of mounting of LV
bushings.
5. Bushing Clearance: (mm)
a) LV to Earth
b) HV to Earth
c) Between LV bushings
(N)
d) Between HV bushings
TANK BASE CHANNEL/ROLLERS
:
1. Size of Channel (mm)
2. Whether channels welded across
the length of the tank
3. Size and type of roller (mm)
(O)
OIL
1. Name of supplier
2. Break down voltage of oil : (kV)
i) Filled in tanked transformer
ii) In storage tank (to be tested by
inspecting officer)
3. Supplier‘s test certificate (enclose
copy)
(P)
(Q)
ENGRAVING :
1. Engraving of Sl.No. and name of
firm
i) On bottom of clamping channel of
cor-coil assembly.
ii) On side wall and top cover of tank
along with date of dispatch.
i) MS plate of size 125x125 mm
welded on width side of stiffener
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
348
Technical specification
ii) Following details engraved (as per
approved GTP)
(a) Serial Number
(b) Name of firm
(c) Order No. and Date
(d) Rating
(e) Name of inspecting Officer
(f) Designation
(g) Date of dispatch
(R)
NAME PLATE DETAILS :
Whether Name Plate is as per
approved drawing
(S)
COLOUR OF TRANSFORMER :
1. Tank body with smoke gray colour
(T)
2. Conservator with white colour
CHECKING OF TESTING
FACILITIES : (Calibration certificate
also to be checked for its validity)
TESTS :
1. No Load Current
2. No Load Loss
3. % Impedance
4. Load Losses
5. Insulation Resistance Test
6. Vector Group Test (phase
relationship)
7. Ratio and Polarity test relationship
8. Transformer Oil test (Break down
voltage)
9. Magnetic Balance
10. Measurement of winding
resistance (HV and LV both)
11. Induced over voltage withstand
test (Double voltage and Double
frequency)
12. Separate source power
frequency withstand test at 28kV for
HV and 3kV for LV (one minute)
13. Air pressure/Oil leakage test
14. Vacuum Test
16. Unbalanced current
test
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
349
Technical specification
16. Temperature rise (Heat Run)
Test
We have specifically checked the
(U)
following and found the same as per
GTP/ deviations observed as
mentioned against each:
i)
Rustlessness of CRGO
lamination used
ii)
iii)
ii) Core steps
iii) Core area
iv) Core weight
v) Winding cross sectional area
a) LV
b) HV
vi) Weight of windings
vii) Clearance between winding and
wall of tank (mm)
a) Length-wise
b) Breadth-wise
viii) Clearance between top of
yoke/top most live part of tap
changer to tank cover.
a) LV
b) HV
ix) Details of Neutral formation
x) Connections to bushings:
a) LV
b) HV
xi) Slope of tank top
xii) Position of mounting of bushings
COMPANY‘S INSPECTING OFFICER
FIRM‘S
REPRESENTATIVE
DATE OF INSPECTION:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
350
Technical specification
1
Annexure - V
PROFORMA FOR PRE-DELIVERY INSPECTION OF
DISTRIBUTION TRANSFORMER
Name of the firm
:
2
Details of offer made
:
(i) Order No. and Date
3
4
5
(ii) Rating
(iii) Quantity
(iv) Sl. No. of transformers
Date of stage inspection of the lot
Reference of stage inspection clearance
Quantity offered and inspected against the
order prior to this lot
(A) ACCEPTANCE TESTS TO BE CARRIED OUT
SL PARTICULARS
NO
1
(a) Ratio Test
OBSERVATIONS
AB/an
BC/bn
CA/cn
2
NO load loss measurement
W1
W2
W3
TOTAL
Multiplying Factor:CT
Watt meter
Total X MF
NET LOSS
3
Load loss measurement
W1
W2
W3
TOTAL
Multiplying Factors:CT
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
SL PARTICULARS
NO
Watt meter
OBSERVATIONS
PT
Total X MF
NET LOSS
Loss at ambient temperature
Loss at 750C (with calculation sheet) (watt)
4
Winding resistance:
H.V. (in Ohms)
(a) At ambient temperature of _________0C
A–B
B–C
C–A
(b) Resistance at 750C.
A–B
B–C
C–A
L.V. (in Ohms)
(a) At ambient temperature of _________0C
a–n
b–n
c–n
(b) Per Phase Resistance at 750C
a–n
b–n
c–n
5
Insulation Resistance (MΩ)
HV – LV
HV – E
LV – E
6
Separate Source Voltage withstand test voltage:
HV 28kV for 60 sec.
LV 3 kV for 60 sec.
7
Induced over voltage withstand test at double
voltage and double frequency
8
No load current at
100 HZ, 866 volts for 60
sec.
90% volts
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
352
Technical specification
SL PARTICULARS
NO
110% volts
9
Unbalance current
10
Vector group test
11
Percentage Impedance at 750C (enclosed
calculation sheets)
12
Transformer oil test (BDV)
13
Oil leakage test
14
Heat run test
15
Bushing clearance (mm)
OBSERVATIONS
Diagram and readings
should be shown in
separate sheets.
To be carried out once
against each order.
HV
LV
(a) Phase to Phase
(b) Phase to Earth
16
17
18
19
Comments on compliance by the firm on the
modifications done as per stage inspection
clearance letter issued.
Whether fittings of the order have been varified
Whether aluminium die cast silicagel breather
with the container is fitted on the transformer
offered.
Whether engraving of Sl.No and Name of firm on
core clamping channel, side wall and top cover of
tank has been verified.
20
Whether MS Plate of size 125x125 mm welded
on with side of stiffener.
21
Whether engraving of name of firm, Sl.No and
Rating of transformer, Order No. and date and
date of Despatch on MS Plate.
22
Copy of calibration certificates of metering
equipments be enclosed.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
353
Technical specification
(B) POINTS TO BE SEEN/DIMENSIONS TO BE NOTED AT THE TIME OF
DISMANTLING OF TRANSFORMERS:
SL PARTICULARS
OBSERVATIONS
No.
1
Details of the transformer dismantled for physical
verification
(a) Rating (KVA)
(b) Sl.No.
2
Whether GI Nut Bolts with one spring one plain
washer provided for tightening the tank cover.
3
Details of gasket used between top cover and Tank
Material:
(i) Thickness (mm)
(ii) Type of joints
4
Whether core is earthed properly with copper strip
(one end should be tightened in between the core
laminations and other end bolted on core clamping
channel)
5
Connections from winding to bushings (describe the
manner in which it has been done)
(a) HV
(b) LV
(c) Formation of Star connection on LV side
6
Winding wire dia and cross sectional area:
(a) HV
(i) Dia (mm)
(ii) Area (sq mm)
(b) LV
(i) L X W X Nos. of layer
(ii) Area (sq mm)
7
Thickness of press board (s) provided between HV
coils to cover the tie rods.
8
Whether painted with oil and corrosion resistant
paint/varnish
(a) Inside of the tank
(b) Inside of the conservator tank
(c) Core clamping and core base channels
(d) Tie rods
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
354
Technical specification
SL PARTICULARS
No.
(e) Core bolts
OBSERVATIONS
9
Whether tie rods and core bolts insulated, if yes,
material of insulation.
10
Whether flap on inner side of top cover provided to
prevent direct falling of oil on core – coil assembly.
11
Method of joints
(a) Between HV Coils
12
Whether engraving of Sl. No. and name of firm done
on bottom channel of core coil assembly.
13
Diameter of copper wire, used for formation of Delta
(should not be less than 1.5 times the dia of
conductor). (mm)
Whether empire sleeves provided upto to the end
portion of HV winding joining to bushing.
14
15
HV coils
(a) Inner dia (mm)
(b) Outer dia. (mm)
16
LV coil
(a) Inner dia (mm)
(b) Outer dia. (mm)
17
Core dia
18
Core height including base channel and insulation in
between (mm)
19
Leg Center of core
20
Clearance between
(a) Core and LV (mm)
(b) HV and LV (mm)
(c) Phase to Phase of HV coils (mm)
(d) Core coil assembly and tank body (mm)
(i) Length-wise
(ii) Width-wise
(e) Top of yoke and top cover (mm)
21
Weight of core only (Kg)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
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Technical specification
SL PARTICULARS
No.
22
Weight of windings (Kg)
OBSERVATIONS
(a) LV
(b) HV
23
Whether core laminations are in one piece, used for
(a) Bottom Yoke
(b) Top Yoke
24
25
26
27
Specific remarks regarding smoothness and rusting
of core used
Volume of oil filled (to be done once against the
order)
Weight of transformer (inclusive of all fittings,
accessories, oil etc. complete)
Inner dimensions of the tank
(a) Length
(b) Width
(c) Height
(i) LV side
(ii) HV side
28
Remarks, if any:
Note: Please ensure that complete details have been filled in the proforma and no
column has been left blank.
Signature of Inspecting Officer
Signature of Firm‘s
Representative
(with name and designation)
(with name and designation)
Date of Inspection:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
356
Technical specification
ANNEXURE –VI
SOURCE OF MATERIALS/PLACE OF MANUFACTURE, TESTING AND
INSPECTION
Sl. Item
Source of
Place of
Place of testing
No.
Material
Manufacture
and inspection
1
Core Laminations
2
Aluminum Conductor
3
Insulated winding wires
4
Oil
5
Press boards
6
Kraft paper
7
MS Plates/Angles/Channels
8
Gaskets
9
Bushing HV/LV
10 Paints
Signature of Firm Representative:
(Name and Designation)
Date:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
357
Technical specification
ANNEXURE –VII
MCCB BOX WITH CU. BUS BAR WITH CABLE CONNECTION INTERFACE
B
MS BOX
Y
R
N
CU.Cable
MCCB
BAKELITE
SHEET
CONNECTOR
BAKELITE FIXING
NUT
RUBBER
GLAND
OUTGOING CABLE
LED INDICATORS FOR
TR
WINDOW
SHED
MCCB WINDOW FOR
ON/OFF
LED INDICATOR FOR
MCCB
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
358
Technical Specification
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
ANNEXURE-A
(To be submitted as First page of the technical offer)
Name & Address of Manufacturer:
Is the factory is free from dust pollution:
Yes/No
Year on which the manufacturing is started:
(Voltage grade wise)
Voltage grade wise yearly manufactured
KVA capacity for last three years (year wise breakup):
Voltage level up to which transformers are manufactured:
Whether transformers are supplied to APDCL earlier:
Yes/NO
Are you manufactured Star Rated transformer, if so up to what level: No/Yes (
name the level)
Do you have supplied star rated transformers to any utility, if yes, name the
Utility and year & quantity of supply (enclosed photo copy of order) : Yes/NO
Type test reports are enclosed along with the detail drawing:
Yes/NO
Name the laboratory where type test were carried out:
Is the type test conform to specification as per the bid document:
No/Yes
Name the Vendors from where CRGO sheets are procured:
Type of drying chamber:
Is the testing facilities are available as per the specifications:
Yes/Partial/No
Are all the information attached as per specifications:
Yes/Partial
Signature of Firm Representative:
(Name and Designation)
Date:
Seal:
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
359
Technical Specification
TECHNICAL SPECIFICATION OF 3-Ф Distribution Transformers of
11kV/433-250V, 250, 315, 500 and 630 KVA
1.0
SCOPE
33.5 This section of the specifications is intended to cover requirements for design,
engineering, manufacture, testing/inspection at manufacturer‘ works before
despatch, forwarding, packing, transporting and delivery at site of outdoor type
naturally air-cooled, 11kV/433-250V Distribution Transformers of capacities 250,
315, 500 and 630 KVA complete with all accessories/fittings, LV side protection
and spare parts. The bidder shall quote the price of transformer complete with
first filling of oil.
34.0 BIDDING
34.1 Each Technical Proposal must be accompanied by each of the following
information/ documents with sufficient details along with other documents and
information mentioned elsewhere to enable the purchaser to make an appraisal
of the quality and suitability of the material and equipment offered.
(e)
(f)
(g)
(h)
Type test certificates of transformer of identical design from CPRI/ERDA
laboratory. The Type test certificates should not be more than 3 (three) years old.
The type rest certificates should also be accompanied by the drawings of
equipment tested so that the test certificates can be directly linked to the
equipments offered. In this regard following points shall also be noted:
(i) Equipment which have not been type tested as above shall not be
accepted. A promise or agreement by a bidder to have the equipment
tested after award of a contract is not acceptable.
Type Test reports to be acceptable must relate directly to the equipment
offered. Type Test reports for a higher class/rating of equipment are
acceptable with a commitment from bidder that the type test will be
performed free of charge on the particular equipment after the award of
contract.
Guaranteed and Other Particulars in the formats given in Schedule - A at the end
of this Section. The bid should also be accompanied by manufacturer‘s literatures
and brochures.
The bidder shall have to submit the Annexure-A as a first page of the technical
offer.
34.2 Failure to meet the requirement of this Clause 2.0 shall render a Bid nonresponsive.
35.0 STANDARDS
35.1 The Transformer and associated accessories shall conform to the latest issues
of the standards as given below, except to the extent explicitly modified in this
specification.
(23) CBIP manual on Transformers.
Publication no 275
(24) CEA Guidelines for Specification of Energy Efficient Outdoor Type
three phase and single phase Distribution Transformers, 2008.
(25) Power Transformers
IS:2026, IEC 76
(26) Insulating oils for transformers and switchgears
IS:335
(27) Bushings for alternating voltages above 1000 V
IS:2099
(28) Creepage distance (mm)
IS: 3347
(29) Outdoor Bushings
IS:3347, DIN 42531 to 33
(30) Specification for low voltage bushings
IS:7421
(31) Dimensions for clamping arrangements for bushings
IS:4257
(32) Specification for Al Wire rods
IS: 5434, ASTM B-233
(33) Specification for Insulating Kraft Paper
IS:9335, IEC 554
(34) Specification for Insulating Press Board
IS:1576, IEC 641
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
(35) Code of practice for installation and maintenance
IS:10028
of transformers
(36) Guide for loading of oil immersed transformers
IS:6600
(37) Paper covered Aluminium conductor
IS:6162
(38) Rectangular Electrical conductor for electrical machine
IS:6160
(39) Electrical Power connector
IS: 5561
(40) Colours for ready mix paints.
IS: 5
(41) Ready mixed paint, brushing zinc chromate, priming
IS 104
(42) Specification for Copper wire rod
IS 12444, ASTM B-49
(43) Testing for steel sheets and strips and magnetic circuits
IS-649
35.2 In case equipment conforms to other international standard which ensure
equivalent or better performance than that specified under Clause 3.1, then
relevant Standards shall be forwarded with the bid.
36.0 GENERAL SERVICE CONDITION
36.1 The climatic conditions at site under which the equipment shall operate
satisfactorily are as follows:(a)
Maximum temperature of air in shade
50º C
(b)
Minimum temperature of air in shade:
- 2º C
(c)
Maximum average daily ambient air temperature
400C
(d)
Maximum yearly weighted average ambient temperature
0
32 C
(e)
Maximum Humidity:
100%
(f)
Average of rainy days per annum:
150
(g)
Average number of days of thunderstorm per annum:
45
(h)
Average number of days of dust storm per annum:
25
(i)Average annual rainfall:
(j) Number of months of tropical monsoon per annum:
(k) Maximum wind pressure:
(l) Altitude (above mean sea level):
2280 mm
5 (May to Sept)
195Kg/m2
200 to 1000 m
37.0 GENERAL TECHNICAL SPECIFICATIONS:
37.1 The Distribution transformer shall be 3-phase; oil immersed and shall have core
type construction, and should be suitable for outdoor service in hot and humid
tropical climate.
37.2 The transformers and all its accessories shall be designed to withstand without
injury, the thermal and mechanical effects of any external short circuit to earth
and of short circuits at the terminals of any winding of values and duration
specified in IS-2026.
37.3 The transformer shall be capable of being loaded in accordance with IS: 6600.
There shall be no limitation imposed by bushings etc.
37.4 The transformer shall be capable of being operated without danger on any
tapping at the rated kVA with voltage variation of plus or minus 10%
corresponding to the voltage of that tapping with normal temperature rise. The
design adopted to achieve this shall be indicated in detail in the offer.
37.5 The transformer shall be suitable for continuous operation with frequency
variation of ±5% from normal 50Hz.Combined voltage and frequency variation
should not exceed the rated V/f ratio by 10%.
37.6 Transformer shall be capable of withstanding thermal and mechanical stress
caused by symmetrical or asymmetrical faults on any winding. The calculation
for the same to be submitted along with the offer.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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361
Technical Specification
37.7 Transformer shall accept, without injurious heating, combined voltage and
frequency fluctuation, which produces the following over fluxing conditions:
i) 125% for 1 minute or 140% for 5 seconds
ii) Over fluxing withstand characteristics up to 140% shall be submitted along
with the bid.
37.8 The thermal ability to withstand short circuit shall be demonstrated by
calculation.
37.9 The maximum flux density in any part of the core and yokes, at normal voltage
and frequency of transformer shall be such that the flux density under over
voltage condition as per Clause 5.5 above shall not exceed 1.9 Tesla. The detail
calculation is to be shown as per Annexure-I.
37.10 The maximum magnetising current at 110% rated voltage shall not be more than
125% of that at 100% rated voltage. Accordingly, the operating flux density for
design should be carefully chosen within the stipulated value to achieve the
above requirement. The Bidder shall quote the practically achievable no
load current at different percentages of rated voltage as per Guaranteed
Technical Particulars which will be verified during no load test.
37.11 The maximum current density in any winding shall not exceed 2.50A/sq.mm for
Copper and 1.50A/sq.mm for Aluminium.
37.12 The sources of prime materials, place of manufacture, testing and inspection
should be shown as per the proforma enclosed in Annexure – VI.
37.13 SUPPRESSION OF HARMONICS
The transformers shall be designed with particular attention to the suppression of
harmonic voltage, especially the third and fifth, so as to eliminate wave form
distortion.
37.14 CENTRE OF GRAVITY
The center of gravity of the assembled transformers shall be low and as near to
the vertical center line as possible. The transformer shall be stable with or
without oil. If the center of gravity is eccentric relating to track either with or
without oil, its location shall be shown on the outline drawing.
38.0 GENERAL CONSTRUCTIONAL FEATURES
38.1 GENERAL
38.2 All material used shall be of best quality and of the class most suitable for
working under the conditions specified and shall withstand the variations of
temperature and atmospheric conditions without distortion or deterioration or the
setting up of undue stresses in any part and also without effecting the strength
and suitability of the various parts for the work which they have to perform.
38.3 Similar parts, particularly removable ones, shall be interchangeable.
38.4 Pipes, screws, studs, nuts and bolts used for external connections shall be as
per the relevant standards. Steel bolts and nuts exposed to atmosphere shall
be galvanized.
38.5 Nuts, bolts and pins used inside the transformers and tap changer shall be
provided with lock washers or locknuts.
38.6 Exposed parts shall not have any pockets where water can collect.
38.7 Internal design of transformer shall ensure that air/gas is not trapped in any
location.
38.8 Material in contact with oil shall be such as not to contribute to the formation of
acid in oil. Surface in contact with oil shall not be galvanized or cadmium plated.
38.9 Labels, indelibly marked, shall be provided for all identifiable accessories. All
label plates shall be of non corrodible material.
38.10 All internal connections and fastenings shall be capable of operating under
overloads and over-excitation, allowed as per specified standards without injury.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
38.11 Transformer and accessories shall be designed to facilitate proper operation,
inspection, maintenance and repairs.
38.12 No patching, plugging, shimming or other such means of overcoming defects;
discrepancies or errors will be accepted.
39.0 SURFACE PREPERATION & PAINTING
39.1 GENERAL
39.1.1 All paints, when applied in a normal full coat, shall be free from runs, sags,
wrinkles, patchiness, brush marks or other defects.
39.1.2 All primers shall be well marked into the surface, particularly in areas where
painting is evident and the first priming coat shall be applied as soon as possible
after cleaning. The paint shall be applied by airless spray according to
manufacturer‘s recommendations. However, where ever airless spray is not
possible, conventional spray be used with prior approval of purchaser.
39.2 CLEANING AND SURFACE PREPERATION:
39.2.1 After all machining, forming and welding has been completed, all steel work
surfaces shall be thoroughly cleaned of rust, scale, welding slag or spatter and
other contamination prior to any painting.
39.2.2 Steel surfaces shall be prepared by shot blast cleaning (IS:9954) to grade Sq.2.5
of ISO 8501-1 or chemical cleaning including phosphating of the appropriate
quality (IS :3618)
39.2.3 Chipping, scraping and steel wire brushing using manual or power driven tools
cannot remove firmly adherent mill-scale. These methods shall only be used
where blast cleaning is impractical. Manufacturer to clearly explain such areas in
his technical offer.
39.3 PROTECTIVE COATING
39.3.1 As soon as all items have been cleaned and within four hours of subsequent
drying, they shall be given suitable anti-corrosion protection.
39.4 PAINT MATERIAL
39.4.1 Following are the types of paint which may be suitably used for the items to be
painted at shop and supply of matching paint to site: Heat resistant paint (Hot oil
proof) for inside surface.
39.4.2 For external surfaces one coat of thermo setting powder paint or one coat of
epoxy primer followed by two coats of polyurethane paint. These paints can be
either air drying or stoving.
39.5 PAINTING PROCEDURE :
39.5.1 All prepared steel surfaces should be primed before visible re-rusting occurs or
within 4 hours, whichever is sooner. Chemical treated steel surfaces shall be
primed as soon as the surface is dry and while the steel surface is still warm.
39.5.2 Where the quality of film is impaired by excess film thickness (wrinkling, mud
cracking or general softness) the supplier shall remove the unsatisfactory paint
coating and apply another coating. As a general rule, dry film thickness should
not exceed the specified minimum dry film thickness by more than 25%.
39.6 DAMAGED PAINTWORK :
39.6.1 Any damage occurring to any part of a painting scheme shall be made good to
the same standard of corrosion protection and appearance as that was originally
applied.
39.6.2 Any damaged paint work shall be made good as follows:
39.6.2.1
The damaged area, together with an area extending 25 mm around its
boundary, shall be cleaned down to bare metal.
39.6.2.2
A priming coat shall be immediately applied, followed by a full paint finish
equal to that originally applied and extending 50 mm around the perimeter of the
original damage.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
39.6.2.3
The repainted surface shall present a smooth surface. This shall be
obtained by carefully chamfering the paint edges before and after priming.
39.7 DRY FILM THICKNESS :
39.7.1 The maximum extent practicable the coats shall be applied as a continuous film
of uniform thickness and free of pores. Overspray, skips, runs, sags and drips
should be avoided. The different coats may or may not be the same colour.
39.7.2 Each coat of paint shall be allowed to harden before the next is applied as per
manufacturer‘s recommendations.
39.7.3 Particular attention must be paid to full film thickness at the edges.
39.7.4 The requirements for the dry film thickness (DFT) of paint and the materials to be
used shall be as given below:
Sl.No
1.
2.
Paint type
Area to be
painted
No. of
coats
Thermo setting powder
paint
Liquid Paint
a) Epoxy (primer)
b) P.U.Paint (Finish coat)
c) Hot oil paint/Varnish
inside
outside
01
01
Total dry film
thickness (min)
(microns)
30
60
outside
outside
inside
01
02
01
30
25 each
35/10
39.8 TESTS FOR PAINTED SURFACE:
39.8.1 The painted surface shall be tested for paint thickness.
39.8.2 The painted surface shall pass the cross hatch adhesion test and impact test as
acceptance tests and Salt spray test and Hardness test as type test as per the
relevant ASTM standards.
Note: The paint work done shall be guaranteed for a minimum period of 5 years
from the date of receipt of the equipment.
40.0 TRANSFORMER TANK
40.1 The Transformer tank and cover shall be fabricated from high-grade low carbon
plate steel of tested quality. The tank and the cover shall be of welded
construction. Minimum thickness of tank bottom and top should be 6 mm and the
tank wall should be 4.0 mm.
40.2 The tank plate and lifting lugs shall be of such strength that the complete
transformer filled with oil may be lifted by means of lifting shackle.
40.3 All beams, flanges, lifting lugs, braces and permanent parts attached to the tank,
shall be welded and where practicable, they shall be double welded.
40.4 The main tank body of the transformer without oil, shall be capable of
withstanding pressure of 225 mm of Hg. Permanent deflection, when subjected
to vacuum, shall not be more than the values as given below:
(All figures in mm)
Horizontal length of flat plate
Permanent deflection
Up to and including 750
5.0
751 to 1250
6.5
1251 to 1750
8.0
1751 to 2000
9.5
2001 to 2250
11.0
2251 to 2500
12.0
2501 to 3000
16.0
Above 3000
19.0
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
40.5 The tank shall further be capable of withstanding a pressure of 0.8 kg/sq.cm (g)
and a vacuum of 0.7 kg/sq.cm (g) without any deformation.
40.6 All bolted connections to the tank shall be fitted with suitable oil-tight gaskets,
which shall give satisfactory service under the operating conditions and
guaranteed temperature rise conditions. Special attention shall be given to the
methods of making the hot oil-tight joints between the tank and the cover as also
between the tank cover and the bushings and all outlets to ensure that the joint
can be remade satisfactorily at site and with ease, with the help of semi-skilled
labour. Where compressible gaskets are used, stops shall be provided to
prevent over-compression. The top cover gaskets should not be exposed to
atmosphere.
40.7 Suitable guides shall be provided for positioning the various parts during
assembly or dismantling.
40.8 Tank stiffeners shall be provided for general rigidity and these shall be designed
to prevent retention of water.
41.0 TANK COVER
41.1 The transformer top shall be provided with a detachable tank cover with bolted
flanged gasket joint. The surface of the cover shall be suitably sloped so that it
does not retain rainwater.
41.2 Each tank cover shall be of adequate strength and shall not distort when lifted.
Inspection opening shall be provided as necessary to give easy access to
bushing. Each inspection opening shall be of ample size for the purpose for
which it is provided, The tank cover and inspection cover shall be provided with
suitable lifting arrangements.
41.3 The tank cover shall be fitted with pockets for thermometer (at the center of the
top cover).
41.4 The tank cover is to enclose the flanged gasket.
41.5 The thermometer pockets shall be fitted with a captive screw top to prevent the
ingress of water.
41.6 Bushings, covers of inspection openings, etc. shall be designed to prevent
ingress of water into or leakage of oil from the tank.
41.7 HV bushings are to be mounted on the top cover. However, for maintenance
purpose the, the termination point of HV leads should have easy accessibility. All
bolted connection shall be fitted with weather proof, hot oil resistant gasket in
between, for complete oil tightness. If gasket is compressible, metallic stoppers
shall be provided to prevent over compression.
42.0 UNDER CARRIAGE
42.1 The transformer tank shall be supported on steel structure with detachable
forged steel flanged wheels suitable for moving the transformer completely filled
with oil.
42.2 Suitable locking arrangement along with foundation bolts shall be provided for
the wheels to prevent accidental movement of the transformer.
42.3 The suitable clamping device should be provided for top and bottom of the
transformer in case where it will be mounted on pole. The clamping device
should suitable for both PSC and Steel Tubular poles. The clamps should be
galvanized as per relevant IS.
42.4 To prevent movement during earthquake, clamping devices shall be provided for
fixing transformer to the foundation. The bidders shall supply necessary bolts for
embedding of the concrete foundation. The arrangement shall be such that the
transformer can be fixed to or unfastened from these bolts as desired. The fixing
of the transformers to the foundations shall be so designed to withstand the
seismic events to the extent that a static co-efficient of 0.5g, applied to the
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
43.0
43.1
43.2
direction of least resistance to that loading will not cause the transformer or
clamping devices as well as bolts to be over stressed.
CORE (MAGNETIC CIRCUIT) AND CONSTRUCTIONAL FEATURES OF
CORE
The magnetic circuit shall be constructed from high grade cold rolled non-ageing
grain oriented silicon steel lamination of M4 or better with thickness of less
than or equal to 0.27 mm
Only primary core material is to be used. The bidder should offer the core for
inspection and approval by the purchaser or third party Inspection Agency during
the manufacturing stage. Bidder‘s call notice for the purpose should be
accompanied with the following document as applicable as a proof towards use
of Prime Core material.
(f) Invoice of supplier,
(g) Mill‘s test certificate.
(h) Packing list,
(i) Bill of loading,
(j) Bill of entry certificate to customs
Core material should be directly procured from either the manufacturer or
their accredited marketing organisation of repute and not through any
agent.
Bidder to have in house numeric controlled Core cutting facility for better
control of quality and also to avoid any mixing of Prime Core material with
second‟s materials. Core cutting machine number and drawings are to be
furnished.
The following procedure is to be adopted for those manufacturers who have no
in-house core-cutting facility:
(1) The bidder should specify the grade, thickness of core material in the offer
along with submission of all graphs/ documents, relating to the grade of core
material, offered by them.
(2) The documents, as mentioned above should be submitted to APDCL along
with the following informations:
a) Purchase order No. & Date.
b) No. of packed coils with package Nos.
c) Gross weight.
d) Net weight
e) Port of loading.
f) Port of discharge.
g) Name of the ocean vessel.
h) Grade and thickness of core material.
i) Any other information, as mentioned on the body of packed coils.
(3) The bidder in its offer will mention the names of at least three Sub-vendors,
to whom they intend to assign their core cutting. Such sub-vendors should
have been approved by other Electricity Boards/ Electrical utilities and are
accredited by some International recognised certification body like ISO: 9000
etc., to ensure that a minimum quality parameters and tolerances are
maintained. The experience, the details of core-cutting facilities, finishing and
testing facilities etc., as available with such sub-vendors should be clearly
outlined in the bid.
(4) On award of contract, the Transformer Manufacture is to assign the corecutting to such sub-vendor(s) for which approval is to be given by APDCL or
its successor companies.
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Technical Specification
11.3 The laminations shall be free of all burrs and sharp projections. Each sheet
shall have an insulating coating resistant to the action of hot oil.
11.4 The design of magnetic circuit shall be such as to avoid static discharges,
development of short circuit paths within itself or to the earthed clamping
structure and production of flux component at right angle to the plane of the
lamination which may cause local heating.
11.5 All steel sections used for supporting the core shall be thoroughly shot or sand
blasted, after cutting, drilling and welding.
11.6 The finally assembled core with all the clamping structures shall be free from
deformation and shall not vibrate during operation. The core shall be carefully
assembled and rigidly clamped to ensure adequate mechanical strength.
11.7 The core clamping structure shall be designed to minimize eddy current loss.
11.8 The framework and clamping arrangements shall be securely earthed.
11.9 The supporting frame work of the cores shall be so designed as to avoid the
presence of pockets which would prevent complete emptying of the tank through
the drain valve or cause trapping of air during filling.
11.10 The oxide/silicate coating given on the core shall be adequate; however,
laminations can be insulated by the manufacturers if considered necessary.
11.11 All parts of the cores shall be of robust design capable of withstanding any
shocks to which they may be subjected during lifting, transport, installation and
service.
11.12 Adequate provision shall be made to prevent movement of the core and winding
relative to the tank during transport and installation or while in service.
11.13 No-load current shall not exceed 1.5% of full load current and will be measured
by energizing the transformer at 433 volts, 50Hz frequency. Increase of voltage
of 433 volts by 12.5% shall not increase the no-load current by 4% (maximum) of
full load current.
12.0 INTERNAL EARTHING
12.3 EARTHING OF CORE CLAMPING STRUCTURE
iii) All internal metal parts of the transformer, with the exception of individual
laminations, core bolts and their individual clamping plates shall be earthed.
iv) The top clamping structure shall be connected to the tank by a copper
strap. The bottom clamping structure shall be earthed by one or more of the
following methods:
c) By connection through vertical tie-rods to the top structure.
d) By a connection to the top structure on the same side of the core
as the main earth connection to the tank.
12.4 EARTHING OF MAGNETIC CIRCUIT
ii)
The magnetic circuit shall be connected to the clamping structure at
one point only
12.5 SIZE OF EARTHING CONNECTIONS
Earthing strip should be tin copper and size will be approved by the purchaser
after getting suppliers offer.
13.0 WINDING
13.3 GENERAL
xviii) The current density of in any part of the windings shall not exceed 2.50
Amps/Sq. mm. for copper and 1.50 Amps/Sq.mm for aluminium.
xix) All windings shall be made of electrolytic high conductivity
aluminium/copper for transformer of capacity 250 KVA and copper above
250kVA, and shaped and braced to provide for expansion and contraction
due to temperature changes. Winding shall be fully insulated as defined in
IS: 2026. All neutral points shall be insulated for the voltage specified in
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
IS: 2026. The winding shall be so designed that all coil assemblies of
identical voltage, rating shall be interchangeable.
xx) Number of HV coils per phase should not be less than six (6) with the type
Crossover/Sectional. Number of secondary (LV) coil should be one with
spiral type winding construction.
xxi) Coil shall be clamped by 8 (eight) numbers of stud and the size should not
be less than 20 mm.
xxii) LV winding shall be such that neutral formation will be at top.
xxiii) Conductor covering for HV winding shall be TPC with minimum 0.35 mm
thickness and for LV conductor TPC with minimum 0.50 mm thickness.
xxiv) Interlayer insulation shall be Nomex/Epoxy dotted Kraft Paper.
xxv) Distribution Transformers shall be designed to withstand the impulse and
power frequency test voltages as per IS: 2026.
xxvi) Magnitude of impulse surges transferred from HV to LV windings by
induction and capacitance coupling shall be limited to B.I.L. of LV winding.
xxvii)
The completed core and coil assembly shall be dried in vacuum at
not more than 0.5mm of mercury absolute pressure and shall be
immediately impregnated with oil after the drying process to ensure the
elimination of air and moisture within the insulation. Vacuum may be
applied in either vacuum oven or in the transformer tank
xxviii)
Winding shall be subjected to a shrinking and seasoning process,
so that no further shrinkage occurs during service. Adjustable devices
shall be provided for taking up possible shrinkage in service.
xxix) Winding shall not contain sharp bends which might damage the insulation
or produce high dielectric stresses. No strip conductor wound on edge
shall have width exceeding six times the thickness.
xxx) Varnish application on coil windings may be given only for mechanical
protection and not for improvement in dielectric properties. In no case
varnish or other adhesive be used which will seal the coil and prevent
evacuation of air and moisture and impregnation by oil.
xxxi) The winding shall be designed to reduce to a minimum, the out-of balance
forces in the transformers at all voltage ratios.
xxxii)
The insulation of transformer windings and connection shall be free
from insulating composition liable to soften, ooze out ,shrink or collapse
during service and be non catalytic and chemically inactive in transformer
oil.
xxxiii)
The coil clamping arrangement and the finished dimensions of any
oil ducts shall be such as will not impede the free circulation of oil through
the ducts.
xxxiv)
Terminals of all windings shall be brought out of the tank through
bushings for external connections
xxxv)
The winding shall be so designed that all coil assemblies of
identical voltage ratings shall be interchangeable and field repairs to the
winding can be made readily without special equipment. The coils shall
have high dielectric strength
xxxvi)
All leads from windings to terminals shall be rigidly supported to
prevent injury from vibration. Guide tubes may be used where possible.
13.4 BRACING OF WINDINGS
13.4.1 The windings and connections of all transformers shall be braced to withstand
shocks, which may occur during transport or due to switching and other transient
conditions during service.
v) Coil clamping rings shall be of suitable insulating material.
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Technical Specification
vi)
14.0
14.3
14.4
14.5
14.6
14.7
15.0
15.1
15.2
16.0
16.1
16.2
16.3
16.4
Permanent current carrying joints in the windings and leads shall be
welded or brazed. Clamping bolts for current carrying parts inside oil shall
be made of oil resistant material which shall not be affected by acidity in
the oil steel bolts, if used, shall be suitably treated.
vii) Adequate barriers shall be provided between coils and core and between
high and low voltage coil. End turns shall have additional protection
against abnormal line disturbances.
viii) Coil should be clamped by 8 (eight) numbers of 20 mm dia tie rods
between top and bottom yoke support channels
BOLTS AND NUTS
Steel bolts and nuts exposed to atmosphere with suitable finishes like cadmium
plated or zinc plated passivated will be used for diameter above 6 mm.
Brass bolts and nuts of less than 6 mm shall not be used for electrical
connections. Where smaller size is required, stainless steel or phosphor bronze
may be used. Sizes and threads will be as per Indian Standard, wherever,
available, otherwise equivalent British Standard will be followed.
All nuts and bolts and pins shall be locked in position with the exception of those
external to the transformer. The bolts shall be fitted in such a manner that in the
event of the nut working loose and falling off, the bolts will remain in position.
All bolts, nuts and washers in contact with non-ferrous parts which carry current
and are exposed to atmosphere shall be of phosphor bronze, where transfer of
current is through bolts.
If bolts and nuts are placed that are in accessible by means of ordinary
spanners, suitable special spanners shall be provided by the supplier.
INSULATION MATERIAL:
Electrical grade insulation epoxy dotted Kraft Paper/Nomex and pressboard of
standard make or any other superior material subject to approval of the
purchaser shall be used.
All spacers, axial wedges / runners used in windings shall be made of precompressed Pressboard solid, conforming to type B 3.1 of IEC 641 – 3 – 2 . For
cross-over coil winding of HV all spacers shall be properly sheared and dovetail
punched to ensure proper locking. All axial wedges / runners shall be properly
milled to dovetail shape so that they pass through the designed spacers freely.
Insulation shearing, cutting, milling and punching operations shall be carried out
in such a way, that there should not be any burr and dimensional variations.
INSULATING OIL
The insulating oil for the transformers shall be of EHV grade, generally
conforming to IS: 335. No inhibitors shall be used in the oil.
The quantity of oil required for the first filling of the transformer and its full
specification shall be stated in the bid.
The design and materials used in the construction of the transformer shall be
such as to reduce the risk of the development of acidity in the oil.
The supplier shall warrant that oil furnished is in accordance with the following
specifications.
a) Appearance
: The oil shall be clear and
transparent and free from
suspended matter or sediment
b) Density at 20oC Max:
0.89g/cm3
o
c) Kinematic Viscosity at 27 C Max: 27 CST
d) Interfacial at 27oC Min.:
0.03 N/m
e) Flash Point:
140oC
f) Pour Point Max:
-6oC
g) Neutralisation Value:
0.03 mg/KOH/g
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
(Total Acidity) Max
h) Electric Strength:
60 kV
(Breakdown Voltage) Min.
i) Dielectric dissipation factor:
0.05
tan delta at 90oC Max
j) Minimum specific resistance:
1 x 1012 ohm cm
(resistivity), at 90oC Min.
k) Oxidation Stability
i) Neutralisation value after Max:
0.40 mg/KOH/g
ii) Total sludge after oxidation max: 0.10% by weight
l) Presence of oxidation Inhibotor:
The oil shall not contain
anti-oxidant Additives
m) Water content Max:
25 ppm
17.0 ACCESSORIES & FITTINGS)
17.1 BUSHINGS:
17.1.1 The bushing shall conform to the relevant standards specified and shall be of
outdoor type. The bushing rods and nuts shall be made of brass material 12 mm
diameter for HT bushings. The tests as per latest IS:2099 and IS:7421 shall be
conducted on the transformer bushings.
17.1.2 For 11 KV, 17.5 kV class bushing and for 0.433 kV, 1.1 kV class bushing shall
be used.
17.1.3 Bushing can be of porcelain/epoxy material. Polymer insulator bushings
conforming with relevant IEC can also be used. LV side bushings shall
invariably be either of epoxy material or polymeric type. The bidder is to
name at least 2/3 vendors of repute who are presently manufacturing
epoxy/polymeric bushings and APDCL will select the vendor from those of
offered at the time of detail engineering.
17.1.4 Dimensions of the bushings of the voltage class shall conform to the Standards
specified and dimension of clamping arrangement shall be as per IS:4257.
17.1.5 Minimum external phase to phase and phase to earth clearances of bushing
terminals shall be as follows :
Voltage
Clearance
Phase to phase
Phase to earth
11 kV
255 mm
140 mm
0.433
75 mm
40 mm
kV
17.1.6 Brazing of all inter connections, jumpers from winding to bushing shall have
cross section larger than the winding conductor. All the Brazes shall be qualified
as per ASME, section-IX.
17.2 TERMINAL CONNECTORS :
17.2.1 The HV bushing stems shall be provided with suitable terminal connectors as per
IS: 5082 so as to connect the jumper without disturbing the bushing stem.
Connectors shall be with eye bolts so as to receive conductor for HV. Terminal
connectors shall be type tested as per IS:5561.
17.2.2 Bird guards are to be provided for all HV bushings.
17.2.3 The terminal connectors to be supplied for both H.V. and L.V. side shall be
universal type suitable for both horizontal and / or vertical take off.
17.2.4 The type of terminal connector, size of connector, material, and type of
installation shall be approved by the APDCL, as per installation requirement
while approving the equipment drawings.
17.3 EARTHING TERMINAL:
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Technical Specification
17.3.1 Two earthing pads (each complete with two nos. (2) tapped holes, M 8 bolts,
plain and spring washers) suitable for connection to 40x6 mm galvanised steel
flat shall be provided each at position close to the two (2) diagonally bottom
corners of the tank. Earthing strip up to the ground level shall be provided by the
bidder.
18.0 Protection & Measuring Devices
A) Conservator Tank
vii.
The conservator tank shall have adequate capacity between highest
and lowest visible levels to meet the requirement of the expansion of
the total cold oil volume in the transformer from minimum ambient
temperature to 90°C. The total volume of conservator shall be 10% of
total oil in the transformer.
viii.
The conservator feed pipe shall be extended 25 mm upwards from
the conservator bed so that a sump is created.
ix.
The conservator should have one oil filling hole of 32 mm size with
gasketed cover. One air release plug of 15mm size will be required.
x.
The conservator tank shall be bolted into position so that it can be
removed for cleaning purposes.
xi.
The conservator tank shall be fitted with prismatic oil level gauge with
minimum and maximum marking.
xii.
The conservator tank shall be provided in a position not to obstruct
the electrical connections to the transformers.
B) Pressure Relief Device
Pressure relief device may be provided at suitable locations which shall be
of sufficient size for rapid release of any pressure that may be generated in
the tank and which may result in damage to the equipment. The device
shall operate at the static pressure of less than the hydraulic test pressure
of transformer tank. It shall be mounted directly on the tank.
C) Oil Preservation Equipment
(i) Oil Sealing Breather
The conservator shall be fitted with a dehydrating filter breather. It shall be
so designed that,
1) Passage of air is through a dust filter & Silica gel
2) Silica gel is isolated from atmosphere by an oil seal.
3) Moisture absorption indicated by a change in colour of the crystals
can be easily observed from a distance.
4) Breather is mounted not more than 1200 mm above rail top level.
5) The breather should have at least 1000 gm of silica gel.
19.0 RADIATORS & VALVES
19.1 RADIATORS
iii)
Radiators shall be of press steel having thickness of 1.2 mm Cold Rolled
Continuously Annealed (CRCA) sheet. and design should be such that all
painted surface can be thoroughly cleaned by hand.
iv) The inlet header of Radiators should be put below the LV bushings in
such a way that in the event of oil leakage from LV bushings, the
circulation of oil through radiators are continuing. The arrangement to be
demonstrated at the time of detail engineering and will be verified during
stage inspection. Failure of this arrangement will lead to total
rejection of offered lot.
19.2 VALVES
19.2.1 Each transformer shall be provided with following valves on the tank:
c)
One fully pilfer proof valve below the top cover..
d)
One 15 mm air release plug.
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Technical Specification
20.0 FITTINGS AND ACCESORIES
20.1 The following fittings shall be provided on each transformer:
o) Conservator fitted with oil filling hole and cap.
p) Prismatic type oil gauge
q) Silica gel breather with oil seal.
r) Pressure relief device for main tank.
s) Pocket on tank cover (placed at mid position) for thermometers.
t) 9 kV, 5 KA lightning arrestors on HT side – 3 No.
u) Oil temperature indicator (for 500kV and above)
v) Valves :i)
Valve (32mm) shall be of globe type .
w) Eearthing terminals with lugs- 2 nos.
x) Rating and diagram plate, non-detachable.
y) Lifting lugs for main tank and top cover.
z) Top tank clamping
aa) Inspection cover.
bb) Terminal connectors on the HV/LV bushing
cc) Bi-directional flanged rollers with locking and bolting device.
dd) Base channel of 100 x 50 mm, 460 mm long with holes to make them
suitable for fixing on a platform or plinth.
ee) 5 (five) year guarantee plate of non-detachable type.
21.0 MISCELLANEOUS
iii)
Padlocks along with duplicate keys as asked for valves‘
iv)
Foundation bolts for wheel locking devices of Transformer shall be
supplied by the Supplier.
v)
The LA should be clamped to HV side bushing with a galvanized earth
strip of size 40x5 mm with two nos of M8 size bolt hole along with
galvanized nut & bolts and the strip should run near to pole for pole
mounted transformer so that the riser from the ground can be
connected properly. LA with polymer insulator housing (as per relevant
IEC) is to be offered. LA with porcelain casing will be rejected.
Preferred manufacturer list for procurement of 9kV, 5kA, metal oxide,
distribution class LA shall be from CGL/Oblum/Rechem/LAMCO.
ii) NAME PLATE
Transformer rating plate shall contain the information as given in clause 15
of IS-2026 (Part-I). The details on rating plate shall be finalised during the
detailed engineering.
22.0 LOSSES
22.1 The bidder shall guarantee individually the no-load loss and load loss without any
positive tolerance. The bidder shall also guarantee the total losses at 50% and
100% load condition (at rated voltage and frequency and at 75 0C).
Table: I
Rating (KVA) Max. No-Load loss (Watts)
Max. Load loss (Watts) at 750C
250
430
2600
315
550
2200
500
700
3600
630
850
4600
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Technical Specification
Table: II
Rating (KVA) Max. Losses at 50% loading
Max. Losses at 100% loading
(Watts)
(Watts) at 750C
250
1050
3320
315
1100
3630
500
1600
5500
630
2000
6640
The above losses are maximum allowable and there would not be any “+ve”
tolerance. Bids with higher losses than the specified values would be treated as
non responsive.
Transformers with losses less than those specified above will be capitalized
during bid evaluation process as per Clause No 22.5.
CAPITALISATION OF LOSSES AND LIQUIDATED DAMAGES FOR
EXCESSIVE LOSSES:
22.2 For the purpose of penalty computation, the test figures of the no-load and the
total losses of each transformer will be compared with the corresponding
guaranteed figures.
22.3 Since IS: 2026 allows certain tolerances on the transformer losses, the bidders
are requested to indicate whether the figures given for guaranteed losses in the
schedule of guaranteed technical particulars are with or without such tolerances.
If tolerances are applicable, the limits for the same should be indicated. In the
absence of any information to this effect, the figures for no-load losses and load
losses will be increased by 10% as provided in the IS. Any change in the figures
assigned for transformer losses will not be permitted after opening of bids and bid
evaluation will be carried out on the basis of information made available at the
time of bid opening.
22.4 Penalties will be applicable if any one or more test loss figures of no-load loss
and total losses exceed the corresponding guaranteed figures. The penalties will
be calculated as follows: (g) For No-load loss, Penalty (in rupees) = {Wi (t) – Wi (g)} x 2R1.
(h) For load loss, Penalty (in rupees)
= {WT (t) – Wi (t) - WI (g)} x
2R2
Where,
WT (t) = Total loss (test value) in W.
WT (g) = Total loss (guaranteed value) in W.
Wi (t) = No-load loss (test value) in W.
Wi (g) = No-load loss (guaranteed value) in W.
W1 (g) = Load loss (guaranteed value) in W.( Copper loss )
R1
= Rs.328/R2
= Rs.181/22.5 For the purpose of comparison of the different bids, the capitalised cost of each
transformer shall be considered. Capitalised cost of the transformer for the
purpose of tender evaluation only shall be calculated as given below:
Capitalised cost in Rs = IC+328 Wi+181 WI(g))
Where,
IC= Quoted price of transformer in Rs
Wi(g) = Guaranteed no load loss in Watt
WI(g)= Guaranteed load loss (copper loss) in Watt
22.6 The loss figures (both guaranteed & test) for the purpose of calculation shall be at
rated frequency and voltage and at principal tap and 75º C.
22.7 If losses are quoted with tolerance limit, then upper positive value will be
considered for capitalization.
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Technical Specification
22.8 Calculation of detail losses including flux density and no load current are to
be furnished for copper loss, iron loss indicating corresponding copper
weight and core weight and considering all parameters and also supported
by the drawings showings details of diameter and height of winding and
core duly signed by manufacturer‟s design personnel. The loss calculation
is to be shown as per proforma in Annexure – II.
23.0 Temperature rise: The temperature rise over ambient shall not exceed the limit
given below:
23.1 Top oil temperature rise measured by thermometer
: 350C
23.2 Winding temperature rise measured by resistance method
: 400C
Bids not meeting the above limits of temperature rise will be treated as
non-responsive.
24.0 MCCB BOX
24.1 MCCB of defined rating and make shall have to be put for LV side protection. The
specification of MCCB and the box shall be as per Schedule-C.
25.0 TESTING AND INSPECTION
25.1 TESTS
(ix)
The Supplier shall carry out a comprehensive inspection and testing
programme during manufacture of the transformer. A detail of inspection
is given in this specification. The manufacturer will submit a testing and
inspection plan at the time of bidding.
(x)
The procedure for testing shall be in accordance with IS 1180/2026 as the
case may be except for temperature rise test.
(xi)
The supplier shall carry out all routine tests on each transformers.
(xii) Special tests other than type and routine tests, as agreed between
purchaser and bidder shall also be carried out as per the relevant
standards.
(xiii) Before dispatch each of the completely assembled transformers shall be
subjected to the routine tests at the manufacturer‘s works.
(xiv) The requirements of on site tests are as listed in these specifications.
(xv) Certified test report and oscillograms shall be furnished to the Purchaser
for evaluation. The Supplier shall also evaluate the test results and rectify
the defects in the equipment based on his and the Purchaser‘s
evaluations of the tests without any extra charges to the Purchaser.
Manufacturer‘s Test Certificates in respect of all associated auxiliary and
ancillary equipment shall be furnished.
(xvi) The bidder shall state in his proposal the testing facilities available at his
works. In case full testing facilities are not available, the bidder shall state
the method proposed to be adopted so as to ascertain the transformer
characteristics corresponding to full capacity testing.
25.1.1
ROUTINE TESTS: (To be conducted on each transformer)
25.1.1.1
Ratio, polarity, phase sequence and vector group.
25.1.1.2
No Load current and losses at services voltage and normal frequency.
25.1.1.3
Load Losses at rated current and normal frequency.
25.1.1.4
Impedance Voltage test.
25.1.1.5
Resistance of windings at each tap.
25.1.1.6
Insulation Resistance.
25.1.1.7
Induced over voltage withstand test.
25.1.1.8
Separate source voltage withstand test.
25.1.1.9
Neutral current measurement- The value of zero sequence current in the
neutral of the star winding shall not be more than 2% of the full load
current.
25.1.1.10
Oil samples (one sample per lot) to comply with IS 1866.
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Technical Specification
25.1.1.11
Measurement of no load losses and magnetizing current at rated
frequency and 90%, 100% and 110% rated voltage.
25.1.1.12
Pressure and vacuum test for checking the deflection.
25.1.2
TYPE TESTS TO BE CONDUCTED 0N ONE UNIT:
25.1.2.1
Temperature rise test.
25.1.2.2
Impulse voltage test: with chopped wave of IS 2026 Part-III, BIL should be
95 KV peak.
25.1.2.3
Short circuit withstand test: Thermal and dynamic ability.
25.1.2.4
Air Pressure Test: As per IS – 1180.
25.1.2.5
Magnetic Balance Test.
25.1.2.6
Un-balanced current test: The value of unbalanced current indicated by
the ammeter shall not be more than 2% of the full load current.
25.1.2.7
Noise level measurement.
25.1.2.8
Measurement of zero-phase sequence impedance.
25.1.2.9
Measurement of Harmonics of no-load current.
25.1.2.10
Transformer tank shall be subjected to specified vacuum. The tank
designed for vacuum shall be tested at an internal pressure of 0.35
Kg/cm2 absolute (250 mm of Hg) The permanent deflection of flat plates
after the vacuum has been released shall not exceed the value given
below:
Horizontal length of flat plate
Permanent deflection
Up to and including 750
5.0
751 to 1250
6.5
1251 to 1750
8.0
1751 to 2000
9.5
2001 to 2250
11.0
2251 to 2500
12.0
2501 to 3000
16.0
Above 3000
19.0
25.1.2.11
25.1.2.12
25.1.2.13
25.1.2.14
25.1.2.15
Pressure relief device test.
Short Circuit Test and Impulse Voltage Withstand Tests: In case the
transformers proposed for supply against the order are not exactly as per
the tested design, the supplier shall be required to carry out the short
circuit test and impulse voltage withstand test at their own cost in the
presence of the representative of the purchaser.
The supply shall be accepted only after such test is done successfully, as
it confirms on successful withstand of short circuit and healthiness of the
active parts thereafter on un-tanking after a short circuit test.
Apart from dynamic ability test, the transformers shall also be required to
withstand thermal ability test or thermal withstand ability will have to be
established by way of calculations.
It may also be noted that the APDCL reserves the right to conduct short
circuit test and impulse voltage withstand test in accordance with the IS,
afresh on each ordered rating at purchaser cost, even if the transformers
of the same rating and similar design are already tested. This test shall be
carried out on a transformer to be selected by the purchaser either at the
manufacturer‘s works when they are offered in a lot for supply or randomly
from the supplies already made to purchaser‘s stores. The findings and
conclusions of these tests shall be binding on the supplier.
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Technical Specification
25.1.2.16
25.1.3
25.1.3.1
25.1.3.2
25.1.3.3
25.1.3.4
25.1.3.5
25.2
25.2.1
25.2.1.1
25.2.2
25.2.2.1
25.2.2.2
25.2.2.3
25.2.3
Type test certificates for the tests carried out on prototype of same
specifications shall be submitted along with the bid. The purchaser may
select the transformer for type tests randomly.
ACCEPTANCE TEST:
At least 10% transformers of the offered lot (minimum of one) shall be
subjected to the following routine/acceptance in presence of APDCL‘s
representative at the place of manufacture before dispatch without any
extra charges. The testing shall be carried out in accordance with IS 1180
and IS 2026.
Checking of weights, dimensions, fittings and accessories, tank sheet
thickness, oil quality, material, finish and workmanship as per GTP and
contract drawings.
Physical verification of core coil assembly and measurement of flux
density of one unit of each rating, in every inspection with reference to
short circuit test report.
Temperature rise test on one unit of the total offered quantity.
At least one transformer of the supplied lot shall be subjected to
tests by a third party (preferably ERDA or CPRI) at the purchaser’s
cost. In case of Failure in such test, the entire lot will be rejected by
APDCL and the cost of the tests will have to be borne by the
supplier.
INSPECTION
Inspection and testing of transformer oil:
To ascertain the quality of transformer oil, the original manufacturer‘s test
report should be submitted at the time of inspection. Arrangement should
also be made for testing of transformer oil, after taking out the sample
from manufactured transformers and tested in the presence of APDCL‘s
representative.
STAGE INSPECTION: To ensure about the quality of transformers, the
inspection shall be carried out by the APDCL‘s representative at following
two stages:During receipt of raw material or any time during the process of
manufacture/assembly as desired by APDCL.
At finished stage i.e. transformers are fully assembled and are ready for
dispatch.
The stage inspection shall be carried out in accordance with Annexure –
IV.
After the main raw-material i.e core and coil material and tanks are
arranged and transformers are taken for production on shop floor and a
few assembly had been completed, the firm shall intimate the APDCL in
this regard, so that an officer for carrying out such inspection could be
deputed, as far as possible within seven (7) days from the date of
intimation. During the stage inspection a few assembled core shall be
dismantled to ensure that the CRGO laminations used are of good quality.
Further, as and when the transformers are ready for dispatch, an offer
about the readiness of transformers, for final inspection for carrying out
tests as per relevant IS shall be sent by the firm along with Routine Test
Certificates. The inspection shall normally be arranged by the APDCL at
the earliest after receipt of offer for pre-delivery inspection. The proforma
for pre delivery inspection of Distribution Transformers is placed at
Annexure – V.
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Technical Specification
25.2.4
25.2.5
25.2.6
25.2.7
25.2.8
In case of any defect/defective workmanship observed at any stage by the
APDCL‘s Inspecting Officer, the same shall be pointed out to the firm in
writing for taking remedial measures. Further processing should only be
done after clearance from the Inspecting Officer/APDCL.
All tests and inspection shall be carried out at the place of manufacture
unless otherwise specifically agreed upon by the manufacturer and
APDCL at the time of purchase. The manufacturer shall offer the Inspector
representing the APDCL all reasonable facilities, without charges, to
satisfy him that the material is being supplied in accordance with this
specifications. This will include Stage Inspection during manufacturing
stage as well as active part inspection during Acceptance Tests.
APDCL shall have every right to appoint a third party inspection to carry
out the inspection process.
The APDCL has the right to have the test carried out at his own cost by an
independent agency wherever there is a dispute regarding the quality
supplied. APDCL has right to test 1% of the supply selected either from
the stores or field to check the quality of the product. In case of any
deviation APDCL has every right to reject the entire lot or penalize the
manufacturer, which may lead to blacklisting, among other things.
Test Reports for bought out items:
The supplier shall submit the test reports for all bought out/sub contracted items
for approval.
Bucholz relay, Oil temperature indicators, Bushings any other item required to
complete the works.
Porcelain, bushings, insulating oil and other associated equipment shall be
tested by the supplier in accordance with relevant IS. If such equipment are
purchased by the supplier on a sub-contract, he shall have them tested to
comply with these requirements.
25.3
Test Reports to be submitted on the following factory test prior to
inspection:
i)
All standard routine tests in accordance IS: 2026 shall be carried out on
each transformer..
vi) Following additional tests shall also be carried out as routine tests on
each transformer:
c)
Magnetic Circuit Test
d)
Oil leakage test on transformer
vii) Following type tests shall be conducted on one transformer of each
rating:
c)
Temp. rise test as per IS: 2026 (Part-I). This test shall be carried
out at the lowest tap.
d)
Lightning Impulse Test shall be carried out in accordance with IS2026 on one transformer of each rating.
viii) Six (6) sets of certified test reports and oscillographs shall be submitted
for evaluation prior to despatch of the equipment. The supplier shall also
evaluate the test results and shall correct any defect indicated by his and
Purchaser‘s evaluation of the tests without charge to the Purchaser.
ix) All auxiliary equipment shall be tested as per the relevant IS. Test
certificates shall be submitted for bought out items.
.
25.4
TANK TESTS
c) Routine Tests
i) Fabrication Stage
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Technical Specification
d)
25.5
i)
ii)
iii)
The tank shall be tested for leakage by being completely filled with air
and applying a pressure equal to the normal pressure plus 35 KN/m 2
measured at the base of the tank. The pressure shall be maintained for
a period of not less than one hour and during that time no leak shall
occur.
ii)Transformer assembly stage
Oil pressure test to be conducted on tank and all other accessories and
assembled for routine test by being completely filled with oil at a
pressure equal to the twice the normal head of oil or to normal pressure
plus 35 KN/m2 whichever is lower . The pressure shall be maintained for
a period of eight hour and during that time no leak shall occur.
Type Test
Pressure Test
Where required by the Purchaser, one transformer tank of each size
together with its radiator, conservator vessel and other fittings shall be
subjected to a pressure corresponding to twice the normal head of oil or
to the normal pressure plus 35 KN/m 2 whichever is lower, measured at
the base of the tank and maintained for eight hours during which no
leakage shall occur.
PRE-SHIPMENT CHECK AT MANUFACTURERS WORKS:
Check for proper packing and preservation of accessories like radiators,
bushings, explosions vent, dehydrating breather, rollers, buchholz relay,
fans, control cubicle connecting pipes & conservator etc.
Check for proper provision of bracing to arrest the movement of core and
winding assembly inside the tank.
Gas tightness test to conform tightness.
26.0 RECEIPT AND STORAGE CHECKS
j.
Check and record condition of each visible parts of the transformers etc. for
any damage.
k. Check for oil and any leakage of oil from the transformer tank, radiators etc.
l.
Visual check HV/ LV bushings for any crack.
m. Check for IR between HV-E, LV-E and HV – LV.
n. Check for oil BDV and water content.
o. Thermometer pockets are to be filled with oil.
p. Colour of Silica gel is blue
q. Bushing arcing horn is set correctly for required gap distance.
r.
Oil is at correct level in the bushing, conservator and tank.
27.0 REJECTION
27.1 The Purchaser may reject any transformer if during tests or service any of the
following conditions arise:
v) No load loss exceeds the guaranteed value by 20% or more.
vi) Load loss exceeds the guaranteed value by 20% or more.
vii) Maximum losses at 50% loading exceeds the prescribed value.
viii) Impedance value exceeds the guaranteed value by ( -) 10% or more.
ix) The difference in impedance values of any two phases during single
phase short circuit impedance test exceeds 2% of the average value
guaranteed by the vendor.
v) Oil or winding temperature rise exceeds the specified value.
vi) Transformer fails on impulse test.
vii) Transformer fails on power frequency voltage withstand test.
viii) Transformer is proved to have been manufactured not in accordance with
the agreed specifications.
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Technical Specification
28.0 DRAWINGS and CALCULATIONS FOR SUBMISSION WITH THE BID
28.1 The Bidder shall furnish with his bid following drawings incorporating the details
mentioned hereunder.
l)
General outline drawing showing dimensions and overall
dimensions, sectional view, core and coil assembly drawing, net
weights and shipping weights, quantity of insulating oil, spacing of
wheels, location off load tap changers etc.
m)
Details of the sectional view of core and winding showing the core
frame size, coil dia and length, conductor size, lead support etc.
n)
Hot spot temperature calculation.
o)
Demonstration to withstand thermal ability as per IS:2026
p)
Calculation of thermal time constant.
q)
Calculation for thermal and mechanical stress caused by
symmetrical or asymmetrical faults on any winding.
g)
Calculation of detail losses including flux density and no load
current are to be furnished for copper loss, iron loss indicating
corresponding copper weight and core weight and considering all
parameters and also supported by the drawings showings details
of diameter and height of winding and core duly signed by
manufacturer‘s design personnel.
r)
GA drawings/details of various types of bushings and connectors.
s)
Illustrative & descriptive literature of the Transformer
t)
List of customers to whom similar equipments have been supplied.
u)
Type test certificates from a recognized institute preferably CPRI of
equipment of similar design and rating.
v)
Performance report of equipment of similar design and rating which
is in satisfactory operation for at least three years. Performance
report issuing officer‘s rank should be S.E./ DGM and above of the
utility.
29.0 QUALITY ASSURANCE PLAN:
The bidders shall invariably furnish the following information along with the bid in
respect of quality assurance, failing which, offers are liable to be ignored.
(a)
(i).
List of important raw materials (CRGO laminations, wires and
strips, transformer oil, insulating paper, press board, bushings and
terminal connectors etc.)
(ii).
Name of Suppliers/ sub suppliers
(iii). List of standards which are followed during testing of raw materials.
(iv). List of test carried out on raw materials along with test certificate.
(i) List of manufacturing facilities.
(j) Level of automation achieved.
(k) Quality control on stages of manufacturing process along with inspection
reports.
(l) List of testing equipments available along with valid calibration certificates.
Manufacturer shall possess 0.1 accuracy instruments for measurement of
losses.
Quality Assurance Plan (QAP) with hold points for Purchaser‘s Inspection as
per Annexure – III.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
379
Technical Specification
30.0 DATA SHEET
SL
NO
DESCRIPTION
20.
21.
22.
Continuous KVA Ratings (CMR)
Number of phases
Rated voltage kV
iii) Primary (HV)
iv) Secondary (LV)
23.
24.
25.
Highest System Voltage, kV
iii) Primary (HV)
iv) Secondary (LV)
Rated frequency, Hz.
Connection of HV, LV
26.
27.
28.
TRANSFORMER CLASS
11/0.433-0.250 KV
250, 315, 500 & 630
3
11
0.433
12
1.1
50±5%
HV Delta & LV Star with
neutral solidly earthed
Solidly earthed
DYN 11
Method of system earthing
Vector group
Insulation Level:
iv) PF withstand voltage, kV
28
(rms.): HV
v) PF withstand voltage, kV
3
(rms.): LV
vi) Lightening impulse voltage, kV
95
(peak) HV
9.2
Minimum Insulation resistance at HV- E : > 2000 MΩ
200C
LV – E : > 1000 MΩ
29.
5%
Percentage Impedance at 75C
and at principal tap
30.
Maximum flux density at rated
1.6
KVA, Maximum System voltage
[12 KV/1.1 KV] and minimum
system frequency [48.5 HZ],
31.
Method of cooling
ONAN
32.
Type of tap changer
No tap switch for 250 &315
KVA. Off Load tap changer for
500 KVA and above Tr.
33.
Number of taps
(+)3% to (-)9% in 5 steps of
3%
34.
Clearance of air, mm
b) phase to phase, HV / LV
285 / 75
phase to earth, HV / LV
140 / 40
35.
Electrical Clearance, mm
a)
Core to LV:
4.0 (up to 250KVA)
4.5 (for 315 KVA)
5 (500 KVA and above)
b)
Between HV & LV
12
c)
HV Phase to Phase
10
d)
Between tank inside & top
150
of Yoke
40
e)
Between yoke to bottom
50
f)Between tap switch and inside
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
380
Technical Specification
SL
NO
36.
37.
38.
DESCRIPTION
TRANSFORMER CLASS
11/0.433-0.250 KV
tank cover
Maximum current density
2.50 Amp / sq. mm for Copper
& 1.5 Amp/sqmm for
Aluminium
Temperature Rise, 0C
(i) Winding
(measured
resistance.
(ii) Top
Oil
(measured
thermometer)
by
35
40
by
Bushings:
3. Rated voltage in kV
1.4 HV bushing
12
1.5 LV bushing
1.1
1.6 Neutral bushing
4. Rated current in Ampere
1.1
2.4 HV bushing
As per IS: 3347 Part III
(Section 1 & 2)
As per IS: 3347 Part I (Section
1 & 2)
As per IS: 3347 Part I (Section
1 & 2)
2.5 LV bushing
2.6 Neutral bushing
6. Rated
impulse
voltage in kV rms.
withstand
3.2 HV bushing
7. One-minute power frequency
withstand test in kV (rms.)
4.4 HV bushing
4.5 LV bushing
95
28
3
4.6 Neutral bushings
8. Minimum Creepage distance in
mm
5.4 HV bushing
5.5 LV bushing
5.6 Neutral
3
350
55
55
31.0 DOCUMENTATION :
31.1 The bidder shall furnish along with the bid the dimensional drawings of the items
offered indicating all the fittings.
31.2 Dimensional tolerances
31.3 Weight of individual components and total weight.
31.4 An outline drawing front (both primary and secondary sides) and end elevation
and plan of the tank and terminal gear, wherein the principal dimensions shall be
given.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
381
Technical Specification
31.5 Typical general arrangement drawing of the windings with the details of the
insulation at each point and core construction of transformer.
31.6 Typical general arrangement drawing showing both primary and secondary sides
and end-elevation and plan of the transformer.
32.0 GUARANTEE:
32.1 The manufacturers of the transformers shall provide a guarantee of sixty (60)
months from the date of commissioning and handover.
32.2 In case of failure within the guarantee period the APDCL will immediately inform
the supplier who shall take back the failed DTR within fifteen (15) days from the
date of intimation at his own cost and replace/repair the transformer within thirty
(30) days of date of intimation with a roll over guarantee.
32.3 The outage period i.e. period from the date of failure till unit is repaired/replaced
shall not be counted for arriving at the guarantee period.
32.4 In the event of supplier‟s inability to adhere to the aforesaid provision,
suitable penal action will be taken against the supplier which may inter alia
include blacklisting of the firm for future business with the APDCL for a
certain period.
33.0 SCHEDULES:
33.1 The bidder shall fill in the following schedule which will be part of the offer. If the
schedule are not submitted duly filled in with the offer, the offer shall be liable for
rejection.
Schedule – A :
Guaranteed Technical Particulars
Schedule – B :
Schedule of Deviations
34.0 DEVIATIONS:
34.1 The bidders are not allowed to deviate from the principal requirements of the
Specifications. However, the bidder is required to submit with his bid in the
relevant schedule a detailed list of deviations without any ambiguity. In the
absence of a deviation list in the deviation schedule, it is understood that such bid
conforms to the bid specifications and no post-bid negotiations shall take place in
this regard.
34.2 The discrepancies, if any, between the specification and the catalogues and/or
literatures submitted as part of the offer by the bidders, shall not be considered
and representations in this regard shall not be entertained.
34.3 If it is observed that there are deviations in the offer in guaranteed technical
particulars other than those specified in the deviation schedules then such
deviations shall be treated as deviations.
34.4 All the schedules shall be prepared by vendor and are to be enclosed with the
bid.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
382
Technical Specification
SCHEDULE - A
GUARANTEED TECHNICAL AND OTHER
PARTICULARS
(To be filled in by Bidder and shall be furnished with the Technical Bid)
Sl.
No
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Description
Name of the Manufacturer
2Installation [indoor/outdoor]
3Reference standards
4Continuous Ratings
a)
Type of cooling
b)
Rating [KVA]
c
Rated voltage
i
HV [KV rms.]
ii
LV [KV-rms.]
d
Highest system voltage
i
HV [KV rms.]
ii
LV [KV-rms.]
e
Rated frequency with ±%
variation
f
Number of phases
g
Current at rated full load and on
principal tap
i
HV [Amps]
ii
LV [Amps]
5Connections
HV
LV
6Connection symbol and vector group
7Temperature rise
a
Top oil temperature rise
b
Winding Temperature rise
c
Temperature gradients between
windings & oil.
d
Limit of Hot spot temperature for
which
the
Transformer
is
designed [°C]
8Type of OFF load tap changing switch
9Tapping on windings for
i
Constant flux/variable
flux/combined
Regulation
ii
Tapping provided at
iii
Number of steps
iv
Range of tapping for variation [+
percent to - percent]
1i
No load loss at rated voltage and
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
383
Technical Specification
Sl.
No
Description
0
ii
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
frequency at principal tap [KW]
No load loss at the voltage
corresponding to highest tap
[KW]
1Load loss at rated output, rated
1frequency, corrected for 75 °C winding
temperature at:- [Copper loss]
i
Normal tap [In KW]
ii
Highest tap [In KW]
iii
Lowest tap [In KW]
1Total losses at normal ratio
3
Maximum losses at 100% loading at
750C
Maximum losses at 50% loading at
750C
1Positive sequence impedance on rated
4KVA base at rated current and
frequency at 75°Centigrade winding
temperature at
i
Normal tap [%]
ii
Highest tap [%]
iii
Lowest tap [%]
1% reactance at rated KVA base at rated
5current and rated frequency at
i
Normal tap [%]
ii
Highest tap [%]
iii
Lowest tap [%]
1% resistance at rated KVA base at
6rated current and rated frequency at
i
Normal tap [%]
ii
Highest tap [%]
iii
Lowest tap [%]
1% Impedance at rated KVA base at
7rated
current and rated frequency at
i
Normal tap [%]
ii
Highest tap [%]
iii
Lowest tap [%]
1a
Polarisation index i.e. ratio of
8
Megger values at 600 secs to 60
secs, (H.V. to E, L.V. to E, &
H.V.to L.V.). Measurement by 1.0
kV motorised megger.
b
Insulation Resistance in MΩ
(At temp ……….0C)
c
In Between
H.V - E
L.V. - E
H.V – L.V.
PI
HV – E :
LV – E :
HV – LV :
Regulation at full load and 75°C
winding temperature expressed
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
384
Technical Specification
Sl.
No
21.
22.
23.
24.
25.
26.
27.
Description
as a percentage of normal
voltage
i
At unity power factor [%]
ii
At 0.8 power factor [lagging][%]
2Efficiency at 75°C winding temperature Unity power
0as derived from guaranteed loss figures factor
and at
a
At full load [%]
b
At ¾ load [%]
c
At ½ load [%]
2i
Maximum efficiency [%]
1ii
Load at which maximum
efficiency occurs[% of full load]
2Short time thermal rating of
2i
HV winding in KA and duration in
seconds
ii
LV winding in KA and duration in
seconds
2Permissible over loading:3a
HV winding
b
LV winding
2Terminal arrangement
4a
High voltage [HV]
b
Low voltage (LV)
2Insulating and cooling medium
5
2Test voltage
HV
6i
Lightning impulse withstand test
0.8 Power
factor
LV
voltage [KVP]
Power frequency withstand test
voltage [dry and wet][for 1
minute] [KV-rms.]
2External short circuit withstand capacity
7[MVA] and duration [seconds]
2Over-fluxing withstand capability of the
8Transformer
2DETAILS OF CORE
9a
Type of core construction
b
Type of corner joints of the core
c
Maximum flux density at
i
Rated voltage [11/0.4 KV] & rated
frequency 50 Hz][in Tesla]
ii
Highest system voltage [12/1.1
KV] and lowest system frequency
[48.5Hz.][in Tesla]
d
No load current, no load loss and No load No Load No
no load power factor at normal current
Loss
PF
ratio
and
frequency
[Amp/KW/p.f.]
ii
28.
29.
30.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
Load
385
Technical Specification
Sl.
No
Description
i
ii
iii
iv
v
vi
vii
viii
ix
x
xi
xii
e
i
ii
iii
iv
v
vi
vii
viii
ix
x
f
i
ii
iii
iv
v
vi
vii
viii
10 percent of rated voltage
25 percent of rated voltage
50 percent of rated voltage
85 percent of rated voltage
100 percent of rated voltage
105 percent of rated voltage
110 percent of rated voltage
112.5 percent of rated voltage
115 percent of rated voltage
120 percent of rated voltage
121 percent of rated voltage
125 percent of rated voltage
Core laminations:Material of core lamination
[M4/HIB]
Grade of core laminations
Thickness of core lamination
[mm]
Specific loss [watt/Kg.] at rated
voltage and rated frequency
Specific loss [watt/Kg.] at highest
system voltage and lowest
system frequency
Whether specific core loss graph
[flux
density
vs.
watt/Kg.
submitted
VA/Kg at rated voltage and rated
frequency
VA/Kg. at highest system voltage
and lowest system frequency
Whether VA/Kg. Vs. flux density
graph Submitted
Insulation of core laminations
CORE ASSEMBLY:Core diameter [mm]
Core window height [mm]
Core leg centre [mm]
Gross core cross-sectional area
[cm²]
Whether details of core widths,
stacks and calculation furnished
as per enclosed annexure
Distance between centers [mm]
Total height of core [mm]
1)
Details of core Clamping
with nos. of core stud.
2)
Material, grade & type
3)
Width
4)
Thickness
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
386
Technical Specification
Sl.
No
31.
Description
5)
Fixing method
ix
Details of top end frame
x
Details of Bottom end frame
xi
Details of clamp plate [Material,
thickness, Insulation]
xii
Total core weight [kg]
xiii
Core loss basing on core loss
graph at operating flux density
[rated
voltage
and
rated
frequency] [kw]
xiv
Core stacking factor
xv
Net core area Sq. cm.
g
Describe location/method of core
grounding
h
Details of oil ducts in core if any
i
Peak value of magnetizing Inrush
current (% of HV rated current).
3DETAILS OF WINDINGS.
0a
Type of winding
b
Material of the winding conductor
c
Maximum current density of
windings [at rated current] and
conductor area
i
HV
ii
L.V.
d
Whether HV windings are
crossover/ Sectional
e
Whether windings are preshrunk?
f
Whether adjustable coil clamps
are provided for H.V. and L.V.
windings?
g
Whether steel rings or perma
wood are used for the windings?
If steel rings used, whether these
are split?
h
Winding Insulation.
i
H.V.
ii
LV Winding
i
Insulating material used for
i
H.V.
ii
L.V Winding
iii
Tapping connection
j
Insulating material used between
i
H.V. and L.V. winding
ii
Core and L.V winding
iii
H.V. winding and core
iv
H.V. to H.V. winding [between
phases]
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
HV
LV
Conductor
area [cm²]
Current density
[A/cm²]
Type & class
Assam Power Distribution Company Ltd
387
Technical Specification
Sl.
No
Description
V
Vi
Vii
k
i
ii
l
i
ii
m
n
o
p
q
r
s
t
u
v
i
ii
iii
iv
v
vi
vii
viii
a
b
Inter coil spacers between HV
sections (mm)
Type of block between HV
sections
Oil duct between
LV to cylinder (mm) :
Cylinder to HV (mm) :
Type of axial coil supports
H.V. winding
LV winding
Type of radial coil supports
H.V. winding
LV winding
Maximum allowable torque on
coil clamping HV & LV bolts
Bare conductor size (mm).
HV :
LV :
Insulated conductor size (mm).
HV :
LV :
Number of coil per phase
HV :
LV :
No. of conductors in parallel
HV :
(Nos.).
LV :
No. of turns/phase
HV coil :
LV coil :
Inside diameter (mm).
HV coil :
LV coil :
Outside diameter (mm).
HV coil :
LV coil :
Axial height after shrinkage (mm). HV coil :
LV coil :
D.C.RESISTANCE
L.V winding at 75 ° C (Ohms).
HV winding at normal tap at 75°
C (Ohms).
HV winding and at highest tap at
75° C (Ohms).
HV winding at lowest tap.
(Ohms).
Total I²R losses at 75 ° C. for
normal tap. (KW).
Total I²R losses at 75 ° C. for
highest tap. (KW)
Total I²R losses at 75 ° C for
lowest tap.(KW).
Stray losses including eddy
current losses in winding at 75°C
(KW).
Normal tap position
Highest tap position
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
388
Technical Specification
Sl.
No
Description
c
d
w
a
b
c
Lowest tap position.
Any special measures taken to
reduce eddy current losses and
stray losses, mention in details
Load losses at 75°C [I²R + stray].
Normal tap position [KW].
Highest tap position [KW].
Lowest tap position [KW].
w
32.
33.
Details of special arrangement
provided to improve surge
voltage
distribution
in
the
windings
3BUSHINGS.
HV
LV
Neutral
1a
Make and type
i
Rated voltage class [KV-rms.]
ii
Rated current [Amps.]
b
Lightning Impulse withstand test
voltage [1.2/50 micro
second][KVP]
c
Power frequency withstand test
voltage
i
Wet for 1 minute [KV-rms]
ii
Dry for 1 minute [KV-rms]
d
Minimum creepage distance in
mm
e
Weight of assembled bushing
[Kg.]
f
Minimum clearance height for
removal of bushing [mm]
g
Under oil flashover or puncture
impulse voltage [KVP]
h
Under oil flashover or puncture
power frequency voltage (KVrms).
i
Phase to earth clearance in air of
live parts at the top of bushings
3Minimum clearance [mm]
In Oil
Out of Oil
2
Betwee Phase Betwee Phase
n
to
n
to
winding Groun winding Groun
s
d
s
d
HV
LV
a
Radial clearance between LV and
HV (mm)
b
Radial clearance between core to
LV (mm)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
389
Technical Specification
Sl.
No
Description
c
34.
35.
End clearance of HV coil to yoke
(mm)
d
End clearance of LV coil to yoke
(mm)
e
Gap between yoke to bottom of
tank (mm)
3Weight [Tolerance + 5%]
3[Approximate value is not allowed]
a
Core [Kg.]
b
Core with clamping [Kg.]
c
H.V. winding insulated conductor
[Kg.]
d
L.V.winding insulated conductor
[Kg.]
e
Coils with insulation [Kg.]
f
Core and winding [Kg]
g
Oil required for first filling
[Liter/Kg.]
h
Tank and fittings with accessories
[Kg.]
i
Untanking weight [Kg.]
j
Total weight with oil and fittings
[kg.]
3DETAILS OF TANK
4a
Material for Transformer tank
b
Type of tank
c
Thickness of sheet
[No approximate value to be
mentioned]
i
Sides [mm]
ii
Bottom [mm]
iii
Cover [mm]
iv
Radiators [mm]
d
Inside dimensions of main tank
[No approximation in dimensions
to be used]
i
Length [mm]
ii
Breadth [mm]
iii
Height [mm]
e
Outside dimensions of main tank
[No approximation in dimensions
to be used]
i
Length [mm]
ii
Breadth [mm]
iii
Height [mm]
f
Thickness of spray galvanisation
of tank bottom.
g
Vacuum recommended for hot oil
circulation [torr]
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
390
Technical Specification
Sl.
No
Description
h
36.
37.
Vacuum to be maintained during
oil filling in Transformer tank [torr]
i
Vacuum to which the tank can be
subjected without distortion [torr]
j
No. of bi-directional wheels
provided
l
Type and make of pressure relief
device and minimum pressure at
which it operates [Kpa]
3CONSERVATOR
5a
Total volume [Liters]
b
Volume between the highest and
lowest visible oil levels [Litres]
3OIL QUALITY
6a
Governing standard
b
Density in gms/cu-cm
c
Kinematics viscosity in CST
d
Inter facial tension at 27°C in N/m
e
Flash point in °C
f
Pour point in °C
g
Acidity [neutralization value] in
mg of KOH/gm
h
Corrosive sulfur in %
i
Electric strength [breakdown
voltage]
i
As received [KV-rms.]
ii
After treatment [KV-rms.]
j
Dielectric dissipation factor [tan
delta] at 90°C
k
Saponification value in mg of
KOH/gm
l
Water content in ppm
m
Specific resistance
i
At 90°C [ohm-cm]
ii
At 27 °C [ohm-cm]
o
Oxidation stability
i
Neutralization value after
oxidation
ii
Total sludge after oxidation
p
Characteristic of oil after ageing
test as per ASTMD-1934
i
Specific resistance at
27°C [ohm-cms]
90°C [ohm-cms]
ii
Tan delta
iii
Sludge content
iv
Neutralization number
v
Details of oil preserving
equipment offered
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
391
Technical Specification
Sl.
No
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
Description
3RADIATORS
7
a
Overall dimensions lxbxh [mm]
b
Total weight with oil [Kg.]
c
Total weight without oil [Kg.]
d
Thickness of radiator tube [mm]
e
Types of mounting
f
Vacuum withstand capability
g
Total radiating surface in sq.m
h
Type and make of material used
for the radiators
i
Total number of radiators/Banks
for
Transformer and dimensions of
tubes
j
Thickness of hot dip
galvanization of radiators
3TEMPERATURE INDICATORS
8a
Make and type
b
Scale
c
Size [lxbxd]
d
Nos.
3APPROXIMATE OVERALL DIMENSIONS
9OF TRANSFORMER
Length [mm]
Breadth [mm]
Height [mm]
4Transformers will be transported with
2oil.
4Types of terminal connectors and
4drawing No
a
HV
b
LV
4Details of painting, galvanization
5conforms to this Specification [Yes/No]
4No. of breathers provided [Nos.]
6
4Type of dehydrating agent and quantity
7used for breathers
4Valve sizes and numbers
8a
Filter valves- mm-Nos
b
Sampling valves- mm-Nos
4a
Type and make of PRV
9b
No. of each type of devices per
transformer
c
Min. pressure at which device
operates
5Please enclose the list of accessories
0and fittings, being provided on
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Assam Power Distribution Company Ltd
392
Technical Specification
Sl.
No
49.
50.
51.
52.
53.
54.
Description
transformer. Please confirm, these are
as stipulated in the tender
5Whether the transformer, covered is
1fully type tested and if so, whether
copies of type test certificates, enclosed
with the tender
5What are the arrangements, available
4for jointing the winding. Preference shall
be given to the tenderer using highfrequency brazing machines. In case
other jointing techniques are used,
adequacy of the same is to be
recorded. Please note that bolted joints
in the winding are not acceptable. This
should be confirmed here
5Please confirm that you will guarantee
5maximum Impedance variation between
phases within the limit of 2% only
5a
Please
confirm
that
the
6
transformer shall be dried by
vapour/ vacuum-phase drying
method. Please specify level of
dryness
b
In case, other methods of drying
are used, the level of dryness, so
achieved should be identical to
that by V/VPD. Adequacy of such
system should be justified
5Whether the Tenderer has got In-House
7core-cutting facility for cutting core
materials for the transformer ratings as
tendered
5In case SL.53 is not confirmed, whether
8the tenderer is agreed to follow the
procedures, as stipulated at clause 12.3
of this technical specification
Signature of Bidder Representative:
Name of Representative:
Designation:
Date & Place:
Seal:
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Sl.
NO
Clause NO.
SCHEDULE - B
Technical Deviation Sheet
Deviations
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33.0 TECHNICAL SPECIFICATION FOR AC DISTRIBUTION CUBICLE FOR
DISTRIBUTION TRANSFORMER
1. Scope
This section of the specification covers the design, manufacture, testing at
works transport to site insurance storage erection and commissioning of 415
volts AC 50Hz AC Distribution Board (Cubicle) complete with all equipments
and accessories as described in subsequent clause for DTR of different
capacity.
2. Constructional features
A) The Cubicle shall be outdoor, made of sheet metal clad type, thickness 2.5mm
in top and back side, 2.00mm in other sides painted with powder coated paints,
comprising of combination MCCB units and bus bar chambers and equipped
with the circuits and equipments as specified later. The enclosure shall
conforming to IP-54 standard. The different circuits shall be mounted above and
below the bus bar chamber to form a suitable arrangement except that the
incomings will be located at the front and mounted below the busbar chambers.
All equipments shall be suitable for the reception of the cables rising from the
ground level the switch boards shall be so designed as to be readily extensible.
B) Type
TYPE
Type of poles
Rated current
Rated operational voltage
Rated insulation voltage
Rated impulse withstand
voltage
Rated frequency
Reference Ambient
Temperature
In
Ue
Ui
Uimp
A
V
V
kV
DN2-400/630
3/4
315, 400, 630
415
750
8
Hz
⁰C
50
40
Rated ultimate S.C. Breaking
capacity (at 415V ac, 50 Hz)
Rated service S.C. Breaking
capacity (at 415 ac, 50 Hz)
Type of release
Icu
kA
35,50,70
Ics
kA
100% of Icu
Current rating
In
Protectio
n
Overload
Instantaneous
A
ThermalMagnetic
315, 400, 630
Microprocess
or
315, 400,
630
0.8-1 In. 3-6
In/6-10/ In
Adjustable
3. Combination MCCB Unit
A) All MCCB shall be triple pole rotary operated type and shall open and close with
snap action. The series combination MCCB shall conform to the provisions of
latest issue of IS 13947-2
B) The MCCB shall be suitable for rated voltage of 415 volts AC., 50 Hz. The rated
current of each unit shall be as specified before. MCCB should be reputed make
such as Havell‘s/Seimen‘s/Schneider etc.
4. Bus Bars
A) The phase and neutral bus bars shall be of high conductivity (as per IS 5082)
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Technical Specification
aluminium of adequate uniform cross section. The bus bars shall be insulated
from the structure by means of durable non-hygroscopic, non-combustible and
non-tracking materials. Bus bar joints shall be bolted type. The Bus bars Shall
have complete insulation with Red, Yellow,Blue and Black colours for phases
and neutral.
5. The 415 Volts, L.T. A.C. switchgear shall have following circuits and equipments:
A) INCOMING:- incoming cable shall be directly connected to the Bus Bar with
proper
size Lug and GI Nuts & Bolts
B) OUTGOING:- .(i) Four no 3-Ph(300Amp, Adjustable) and one 1-Ph (32A,
Adjustable) MCCB as Out going for 500KVA DTR and Above.
(ii)
(iii)
(iv)
6.
7.
Three no 3- Ph (300Amp,Adjustable) MCCB and one 1-Ph
(32Amps ,adjustable) MCCB as outgoing for DTR 315 & 250
KVA.
Two no 3-Ph (200Amp,Adjustable) MCCB and one no 1-Ph
(32 A,mp, adjustable) MCCB for DTR 100 & 63 KVA
One 3-Ph(100Amp,Adjustable) and one 1-ph MCCB for 25
KVA DTR
.
Name Plate
The board shall be provided with nameplate covering all technical data and also
name of the project shall be clearly mentioned ―RAPDRP‖
Cubicle Supporting structure
The Cubicle shall be fitted by fixing GI channels in poles or by means of some
other supporting structures in convenient height for easy maintanace keeping
sufficient clearance from ground. All nuts and bolts shall be of GI.
8.
Inspection
Inspection may be carried out by the purchaser or third party nominee at any stage
of manufacture. The supplier shall grant free access to the purchaser‘s
representative or third party nominee at a reasonable time when the work is in
progress. Inspection and acceptance of any equipment under this specification by
the purchaser shall not relieve the supplier of his obligation of furnishing equipment
in accordance with the specification and shall not prevent subsequent rejection if
the equipment is found defective.
9.
The design and drawing should be submitted along with the offer.
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Technical Specification
TECHNICAL SPECIFICATION FOR AC 3 PHASE 4 WIRE CT/CT- PT
OPERATED FULLY STATIC THREE VECTOR ENERGY METER (AMR
COMPATIBILITY WITH DLMS PROTOCOL FOR DTR METERING
1. OBJECTIVE & SCOPE
This scope shall cover design, engineering, manufacture, assembly, inspection, testing
at manufacturers works before dispatch, packing, supply and delivery at destination,
subsequent storage, erection and commissioning at site (including insurance during
transit and storage), of 0.5S accuracy class fully static 3 phase–4 wire CT operated
three-vector energy meter for R-APDRP works along with other metering accessories
such as metering cabinet, CTs of relevant accuracy class etc. detailed out in the
specification. The meter shall be suitable for measurement of different electrical
parameters as per the energy and power demand requirement in an AC
balanced/unbalanced system over a power factor range of zero lag to unity. These
meters should have communication port to interface for remote meter reading (AMR
Compatible).
2. APPLICATION
On Distribution Transformers – The pole mounted meter cabinets with the CTs and meters
are to be installed for metering of Distribution Transformers.
3. WORKING ENVIRONMENT
3.1. As per IS 14697-1999 (reaffirmed 2004). Meter to perform satisfactorily under
Non-Air Conditioned environment (within stipulations of IS)
3.2. The meter shall be suitable designed for satisfactory operation under the hot and
hazardous tropical climate conditions and shall be dust and vermin proof. All the
parts and surface, which are subject to corrosion, shall either be made of such
material or shall be provided with such protective finish, which provided suitable
protection to them from any injurious effect of excessive humidity.
3.3. The meter casing should have IP 51 degree of protection.
4. SERVICE CONDITION
4.1. The meter shall be suitable for satisfactory continuous operation under
the following tropical conditions:a)
Maximum ambient temperature in a closed box
:
65 °C
b)
Maximum ambient temperature in shade
:
55 °C
c)
Relative Humidity
:
10 to 95%(noncondensing)
d)
Maximum annual rainfall
:
2280 mm‘
e)
Maximum wind pressure
:
150 Kg/m. sq.
f)
Maximum altitude above mean sea level
:
up to1000 meters
g)
Isoceraunic level
:
60 days/year
h)
Seismic level (Horizontal acceleration)
: 0.3g
i)
Average number of thunderstorms/annum
:
40
(5
months)
k)
Minimum ambient air temperature
:
-10°C
4.2. The climate is moderately hot and humid, conducive to rust and fungus growth.
The climatic conditions are also prone to wide variations in the ambient conditions.
Smoke is also present in atmosphere. Lighting also occurs during rainy season.
5.
APPLICABLE STANDARDS
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5.1. Unless otherwise stated elsewhere in this specification the energy meter
shall be of accuracy Class 0.5S for active/reactive /apparent energy and conform to
relevant clauses of following standards or report to be read with up to date and latest
amendments/revision thereof in all respect: 1. Guidelines on ―Data Exchange for Electricity Meter Reading, Tariff and Load
Control – Companion Specification‖ related to IEC 62056 series of standards;
2. IS-14697/1999 (reaffirmed 2004) Specification for AC Static Transformer
operated Watt Hour & VAR-Hour meters (class 0.5S & 0.2 S);
3. IS-15707 Specification for Testing, evaluation, installation & maintenance of
AC Electricity Meters-Code of Practice;
4. CBIP Report No. 88 /No. 304 : Specification for AC Static Electrical Energy
Meters.
5. Metering code for Assam Grid Regulations-2004 by AERC.
5.2. The equipment meeting with the requirements of other authoritative standards,
which ensure equal or better quality than the standard mentioned above, also shall
be considered; in case of conflict related with communication protocol, the
Guidelines on ―Data Exchange for Electricity Meter Reading, Tariff and Load Control
– Companion Specification‖ shall prevail upon. For any unresolved conflict related
with other parts of this specification the order of priority shall be – 1. Standard
Technical specification for 3p/4w CT/PT operated fully static AMR compatible Trivector energy meters for R-APDRP projects. II. IS 14697/1999 (reaffirmed 2004).
6.
GENERAL TECHNICAL REQUIREMENT
1
TYPE
2
3
FREQUENCY
ACCURACY
CLASS
SECONDARY
VOLTAGE
BASIC CURRENT
(Ib)
MAXIMUM
CONTINUOUS
CURRENT
POWER FACTOR
DESIGN
4
5
6
7
8
AMR Compatible Static, 3 Ph, 4 Wire Tri-Vector
Energy Meter Import type for DTR
50 Hz ±5%
0.5S
Suitable for operation for 3 x 415V
-/5 Amps. as per requirement specified
2.0 Ib;
(Starting and Short time current shall be as per
IS-14697)
0.0 Lag -Unity- 0.0 Lead
Meter shall be designed with application specific
integrated circuit (basic) or micro controller; shall
have no moving part; electronic components shall be
assembled on printed circuit board using surface
mounting technology; factory calibration using high
accuracy (0.05 class) software based test bench.
Assembly of electronic components shall be as per
ANSI/IPC-A-610 standard.
7. GENERAL ELECTRICAL REQUIREMENT
7.1 STARTING CURRENT
The meter shall start and continue to register at the current 0.1% of Ib.
7.2 RUNNING WITH NO LOAD
When the 115% of rated voltage is applied with no current flowing in the current
circuit, the meters shall not register any energy and test output of the meter shall not
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Technical Specification
be more than one pulse/count on "no load".
7.3 POWER SUPPLY VARIATION
The extreme power supply variation (which an operating meter should withstand
without damage and without degradation of its meteorological characteristics when it
is subsequently operated under its operating conditions) is as follows.
Voltage
: 70% to 120 % of Vref
Frequency
: 45 Hz to 55 Hz
The manufacturer can also offer meters, which can withstand higher variations.
7.4 ACCURACY
The class of accuracy of the meter shall be 0.5S for DTRs . The class of
accuracy of CT shall be 0.5. The accuracy should not drift with time.
7.5 POWER CONSUMPTION
The active and apparent power consumption in each voltage circuit of the CT
Operated meters at reference voltage; temperature and frequency shall not
exceed the limit as specified by the latest amendment of IS 14697 per phase.
The apparent power consumption in each current circuit for the CT Operated
meters at basic current, reference frequency and reference temperature shall
not exceed 1.0 VA per phase.
8. PERFORMANCE UNDER INFLUENCE QUANTITIES
8.1.The meters performance under influence quantities shall be governed by IS
14697-1999 (reaffirmed 2004). The meter should be designed and protected
such that all external effects and influences shall not change its performance &
shall work satisfactorily within guaranteed accuracy limits, as specified in IS
14697(latest version).
9. MANUFACTURING PROCESS, ASSEMBLY AND TESTING
9.1. Meters shall be manufactured using latest and ‗state of the art‘ technology and
methods prevalent in electronics industry. The meter shall be made from high accuracy
and reliable surface mount technology (SMT) components. All inward flow of major
components and sub assembly parts (CT, PT, RTCs/Crystal, LCDs, LEDs, power circuit
electronic components etc.) shall have batch and source identification. Multilayer ‗PCB‘
assembly with ‗PTH‘ (Plated through Hole) using surface mounted component shall
have adequate track clearance for power circuits. SMT component shall be assembled
using automatic ‗pick-and-place‘ machines, Reflow Soldering oven, for stabilized setting
of the components on ‗PCB‘. For soldered PCBs, cleaning and washing of cards, after
wave soldering process is to be carried out as a standard practice. Assembly line of the
manufacturing system shall have provision for testing of sub-assembled cards. Manual
placing of components and soldering, to be minimized to items, which cannot be
handled by automatic machine. Handling of ‗PCB‘ with ICs/C-MOS components, to be
restricted to bare minimum and precautions to prevent ‗ESD‘ failure to be provided.
Complete assembled and soldered PCB should undergo functional testing using
computerized Automatic Test Equipment.
9.2. Fully assembled and finished meter shall under go ‗burn-in‘ test process for 24
Hours at 50 degree Celsius (Max. temperature to not exceed 60 degree Celsius) under
power-on no load condition.
9.3. Test points should be provided to check the performance of each block/stage of the
meter circuitry.
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Technical Specification
9.4. RTC shall be synchronized with NPL time at the time of manufacture. Meters testing
at intermediate and final stage shall be carried out with testing instruments, duly
calibrated with reference standard, with traceability of source and date.
10.
GENERAL & CONSTRUCTIONAL REQUIREMENTS
10.1. The case, winding, voltage circuit, sealing arrangements, registers,
terminal block, terminal cover & name plate etc, shall be in accordance with the
relevant standards. The meter should be compact & reliable in design, easy to
transport & immune to vibration & shock involved in the
transportation & handling. The construction of the meter should ensure
consistence performance under all conditions especially during storms/heavy
rains/very hot weathers. The insulating materials used in the meter should be
non-hygroscopic, non-ageing & have tested quality. The meter should be sealed
in such a way that the internal parts of the meter become inaccessible.
10.2. Meters shall be designed and constructed in such a way so as to avoid
causing any danger during use and under normal conditions. However, the
following should be ensured.
a) Personal safety against electric shock
b) Personal safety against effects of excessive temperature.
c) Protection against spread of fire
d) Protection against penetration of solid objects, dust & water
e) Protection against fraud
f) Protection against pilferage
10.3
The meter should be housed in a safe, high grade engineering plastic /
polycarbonate casing, which is of projection mounting type and is dust/moisture proof,
conforming to IP-51 of BIS 12063 / IEC 529, vermin proof and sturdy.
10.4. All insulating material used in the construction of meters shall be nonhygroscopic, non-ageing and of tested quality. All parts that are likely to develop
corrosion shall be effectively protected against corrosion during operating life by
providing suitable protective coating.
10.5. The meter shall be supplied with a transparent extended terminal block cover
(ETBC). The meter base, meter cover, terminal block and ETBC shall be made of
unbreakable high grade fire resistant non-flammable reinforced, polycarbonate (not
bakelite) or equivalent high grade engineering plastic, which should form an extension of
meter cases and have terminal holes and shall be of sufficient size to accommodate
insulation of the conductors, meeting the requirement of IS 14697.1999 / CBIP.88.
The extended terminal block cover should be separately sealable at two places
and housed at the bottom of the meters and once sealed should prevent
unauthorized tampering.
The terminal block should have sufficient insulating properties, mechanical strength and
should have house plated solid brass/steel terminals with two fixing screws per terminal.
The terminals should be designed to withstand high overload with cage clamp.
10.6.
The meter shall have an operation indication device such as a blinking LED. The
operation indicator shall be visible from the front window and capable of being monitored
conveniently with suitable testing equipment.
10.7.
The meter-base, meter cover, terminal block and ETBC shall be made of
unbreakable, high grade, fire resistant, reinforced, non-flammable, polycarbonate or
equivalent high grade and good quality engineering plastic certified by NABL accredited
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laboratory preferably CIPET
10.8.
The meter cover shall have one window. The window shall be of transparent,
high-grade engineering plastic certified by CIPET for easily reading all the displayed
values/parameters, nameplate details and observation of operation indicator. The window
shall be ultrasonically welded with the meter cover and the meter cover should be
ultrasonically welded to the meter base such that it cannot be removed undamaged
without breaking the meter cover.
10.9.
The terminal block, the ETBC and the meter case shall ensure reasonable safety
against the spread of fire. They should not be ignited by thermal overload of live parts in
contact with them.
10.10. The meter shall have tin plated brass/steel terminals or nickel plated brass
terminals. The terminals shall have suitable construction with barriers and cover to
provide firm and safe connection of current and voltage leads of stranded copper
conductors or copper reducer type terminal ends (thimbles).
10.11. The manner of fixing the conductors to the terminal block shall ensure adequate
and durable contact such that there is no risk of loosening or undue heating. Screw
connections transmitting contact force and screw fixing which may be loosened and
tightened several times during the life of the meter shall be such that the risk of corrosion
resulting from contact with any other metal part is minimized. Electrical connections shall
be so designed that contact pressure is not transmitted through insulating material. The
internal diameter of the terminal holes shall be 5.5 mm minimum. The clearance and
creepage distance shall conform to relevant clause of IS 14697:1999/CBIP technical
report No.88.
10.12. The entire and construction shall be capable of withstanding stresses likely to
occur in actual service and rough handling during transportation. The meter shall be
convenient to transport and immune to shock and vibration during transportation and
handling.
10.13. Bidder will submit predefined copies (Qty. indicated in Bid Proposal Sheets) of
all the software‘s (meter reading software for HHU/CMRI, Base computer software for
meter data analysis and technical details).
10.14.
It should be possible to check the healthiness of phase voltages by displaying
all the voltages on the meter display.
10.15. The meter shall have three fixing holes, one at the top and two at the bottom.
The top hole shall be provided with a special clip at the back of the meter so that holding
screw is not accessible to the consumer after fixing the meters. The lower fixing screws
shall be provided under the sealed terminal cover. The requisite fixing screws shall be
supplied with each meter.
11. TROPICAL TREATMENT
11.1. All parts, which are subject to corrosion under normal working conditions, shall be protected
effectively. Any protective coating shall not be liable to damage by ordinary handling or
damage due to exposure to air, under normal working conditions. Meters shall withstand
solar radiation. The meters shall be suitably designed and treated for normal life &
satisfactory operation under the hot and hazardous tropical climatic conditions as specified
in clause no. 2. The meter shall work from -10°C to +55°C and RH 95% non-condensing
type.
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12. QUALITY
12.1. Overall the quality of the meter should be good and the service life of the
meter shall be more than the guarantee period. The material, components
used for manufacturing the meter shall be of premium quality. The LCD
display shall not fade with time and the display annunciators should be
visible. Functionality of the meter shall not be affected by the harsh
environmental conditions. Quality meters shall be given preference and the
performance of previous installed meters shall be analyzed before awarding
the tender. Aesthetically, the meter shall be of premium quality.
12.2. The meter shall have a design to operate satisfactory for 10 years under
normal electrical condition and guaranteed life of 66 months from the date
of commissioning against manufacturing and design defects. The meters
found defective with in guaranteed period should be replaced/repaired by
supplier free of cost with in one month of intimation.
13 SEALING OF METER
13.1. Reliable sealing arrangement should be provided to make the meter tamper
proof and avoid fiddling or tampering by unauthorized persons. For this, at least
two no. of seals on meter body, two no. of seals on meter terminal cover and one
no. of seal on communication port and one seal for the meter cabinet shall be
provided. All the seals shall be provided in front side only. Please refer technical
specification for specification for sealing system. Except the meter cover seals all
other seals should be provided loose.
14. MARKING OF METERS
14.1. The marking of meters shall be in accordance with IS: 14697 /1999
(reaffirmed 2004). Every meter shall have nameplate beneath the meter cover
such that the nameplate cannot be accessed without opening the meter cover and
without breaking the seals of the meter cover and the nameplate shall be marked
distinctly and indelibly. The basic marking on the meter nameplate shall be as
follows:
a) R-APDRP Project
(Details to be given later)
b) Manufacturer‘s name & trade mark
c) Type, Designation/ Category of Meter
d) No. of phases & wires
e) Reference Voltage
f) Rated secondary Current of CT
g) Reference Standard: IS 14697
h) Principal unit(s) of measurement
i) Meter Constant ( imp/kwh, kvARh)
j) Class index of meter
k) Serial number
l) Month and Year of manufacture
m) ―Property of ―APDCL‖
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n) Purchase Order No. & Date
o) Guarantee period
14.2. The meter shall also store name plate details as given in the table A5.1 of
annexure of the guideline document. These shall be readable as a profile as and
when required.
15.
CONNECTION DIAGRAM
The connection diagram of the meter shall be clearly shown for 3 phase 4 wire
system, on inside portion of the terminal cover. The meter terminals shall also be
marked and this marking should appear in the above diagram.
16. COMMUNICATION CAPABILITY
16.1. The meter shall be provided with two ports for communication of the
measured/collected data as per the guideline document for DLMS/COSEM energy
meters:
16.2. LOCAL COMMUNICATION PORT
The energy meter shall have a galvanically isolated optical communication port
located in front of the meter and complying with the hardware specifications
detailed in IEC-62056-21 for data transfer to or from a hand held DLMS
compliant Data Collection Device (Common Meter Reading Instrument, Hand
Held Units etc.) with proper security and without error.
16.3 REMOTE COMMUNICATION PORT
Meter shall have an additional communication port (RS 232/485) for periodic
data
transfer
by
remote
access
through
suitable
modem
(GPRS/GSM/EDGE/CDMA/PSTN/). Meter shall operate on open DLMS protocol
and will be individually addressable. Meters with similar kind of RS 485 ports
shall be possible to hook up in multi-drop arrangement for exporting data to the
remote end server through suitable communication medium. Both ports shall
support the default and minimum baud rate of 9600 bps.
17.
DATA COLLECTION DEVICE
17.1. To enable local reading of meters data a DLMS compliant data collection
device (HHU, CMRI/Laptop etc;) shall be used. This device shall be as per
specification given in the guideline document. It shall be compatible to the DLMS
compliant energy meters that are to be procured /supplied on the basis of this
specification. This device shall be supplied by the meter manufacturer along with
the meter free of cost (one unit per 100 meters).
17.2. Preferred equipment is a laptop of general configuration so as to be
compatible for data downloading with ease form DLMS compliant meters.
18.
QUANTITIES TO BE MEASURED AND DISPLAYED
The meter shall be capable of measuring and displaying the following electrical
quantities within specified accuracy limits for poly-phase balanced or unbalanced loads:
18.1. Instantaneous Parameters such as phase and line voltages, currents, power
factors, overall kVA, kW, kVAr, power factor, frequency etc as per details
given in the table below and the guideline document annexure.
18.2. Block Load Profile Parameters such as kVAh, kWh, kVArh (lag, lead),
Maximum Demand (MD) in kW & kVA, power factor, phase and line
voltages, currents etc as per details given in the table below and the
guideline document annexure.
18.3. Daily Load Profile Parameters such as cumulative energy kWh (import,
export), cumulative kVAh (while kW- import/export), cumulative energy
kVArh (quadrant-1/2/3/4), reactive energy high (V>103%)/low (V<97%), etc
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Technical Specification
as per details given in the table below and the guideline document annexure.
18.4. In addition to above the meter shall also record the Name plate details,
programmable parameters (readable as profile), occurrence and restoration
of tamper events along with the parameters (Table A5.1,A 5.2 and A 6.1 to A
6.8 respectively of guideline document).
Detail of category wise parameters requirement suitable for specific location
such as feeder/DT metering, interface points/boundary points is given in
following tables :
Category
Parameter group
GUIDELINE
DOCUMENT Indian Companion
Specification Annexe
Substation Feeder/ Distribution Instantaneous parameters
A2.1
Transformer meter
Distribution
Transformer/
Block Load Profile parameters
Block Load Profile parameters
Billing Profile parameters
Name Plate details
Programmable Parameters
Event Conditions
A2.2
A4.2
A4.3
A5.1
A5.2
A6.1 to A6.7
Logging parameters for each of
Capture parameters for
A6.8
the
event
event condition – shall be
as applicable (Event Log
selected
Profile)
The
OBIS code for each parameter
shall be as identified as per DLMS /COSEM
protocol/ Indian companion standard.
18.5. Demand Integration period shall be selectable between 15/30 minutes,
19.
DISPLAY OF MEASURED VALUE
19.1. The measured value(s) shall be displayed on seven segments, seven digit (with ±
indication), parameter identifier, backlit Liquid Crystal Display (LCD) display unit/register,
having minimum character height of 10 mm, wide viewing angle. LCD shall be suitable for
temperature withstand of 70 degree centigrade.
19.2. The data should be stored in non-volatile memory. The non-volatile memory should
retain data for a period of not less than 10 years under unpowered condition. Battery
back-up memory will not be considered as NVM.
19.3. The meter should have facility of auto display mode where all parameters
automatically scroll within the specified time and a manual mode where the parameters
can be read by push button operation. In auto display mode each parameter shall on
display for 10 seconds. The display ―off‖ period between two cycles shall not exceed 30
seconds. The register should not roll over in between this duration.
19.4. It should be possible to easily identify the single or multiple displayed parameters
through symbols/legend on the meter display itself or through display annunciators.
19.5. Meter shall have Scroll Lock facility to display any one desired parameter
continuously from display parameters for at least 5 minutes.
19.6. The register shall be able to record and display starting from zero, for a minimum of
1500 hours, the energy corresponding to rated maximum current at reference voltage and
unity power factor. The register should not roll over in between this duration.
The principle unit for the measured values shall be Wh/kWh/MWh for active
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Technical Specification
energy, VArh/kVArh/MVArh for reactive energy & VAh/kVAh/MVAh for apparent
energy. Bidder shall mention the scale in which the meter displays the energy
values.
There should also be a provision through the push button mode to access a high
resolution display of the principle unit of measurement for testing purpose. This
high resolution display should provide for displaying the measured units up to 4
decimal point without any rounding off the digits in case of power failure.
20.
DISPLAY PARAMETERS & DISPLAY SEQUENCE
a) The meter shall display the following required parameters in two different
modes as follows:
A) Auto-Display Parameters for CT operated Static Meters:1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
LED/LCD test
Date
Real Time
Cumulative Reset Count
Phase to Neutral Voltages (R,Y,B) :
Line Currents(R,Y,B).
:
Bill point Active Energy (Kwh) : History 1
Bill Point Average Power Factor : History 1
Bill Point Power-on-hours : History 1
Bill Point Tamper Count : History 1
Bill Point TOD Active Energy (Kwh - REG 1,2,3) : History 1
Bill Point TOD Maximum Demand (KVA - REG 1,2,3) : History 1
Instantaneous Average Power Factor
Cumulative Current Active Energy (Kwh)
Instantaneous Load (KW)
Indication of any present occurrence of tamper (i.e. existing tamper)
B) Push Button-Display (with back scroll facility) Parameters for CT
operated Static Meters:1. LED/LCD test
2. Date
3. Real Time
4. Rising Demand (KVA) with elapsed time
5. Phase to Neutral Voltages (R,Y,B)
6. Line Currents (R,Y,B)
:
7. Supply Frequency
8. Instantaneous Power Factor
9. Instantaneous Load, Active, Reactive, Apparent
10. Cumulative Reset Count
11. Bill Point Active Energy (Kwh) : History 1
12. Bill Point Apparent Energy (Kvah): History 1
13. Bill Point Average Power Factor : History 1
14. Bill Point Power-on-hours : History 1
15. Bill Point Tamper Count : History 1
16. Bill Point TOD Active Energy (Kwh - REG 1,2,3) : History 1
17. Bill Point TOD Apparent Energy (Kvah REG 1,2,3) : History 1
18. Bill Point TOD Maximum Demand (KVA - REG 1,2,3) : History 1
19. Cumulative Power-on-hours
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20. Cumulative Maximum Demand (KVA 0-24 HRS)
21. Cumulative Current Active Energy (Kwh)
22. Cumulative Current Reactive Lag Energy (Kvarh-Lag)
23. Cumulative Current Reactive Lead Energy (Kvarh-Lead)
24. Cumulative Current Apparent Energy (Kvah)
25. Cumulative Current TOD Active Energy (Kwh - REG 1,2,3)
26. Cumulative Current TOD Apparent Energy (Kvah REG 1,2,3)
27. Current TOD Maximum Demand (KVA - REG 1,2,3)
28. Indication of any existing Tamper
29. Cumulative tamper occurrence counts
30. Tamper information as mentioned in the relevant clauses of the specification
should be recorded and displayed in the push button display
31 Connection Check.
C) One high resolution display for Kwh & Kvarh suitable for easy dial testing of
the meter.
Data Transfer through HHU/CMRI: Apart from the display parameters (Auto
display & Push Button) as specified above and the standard parameters as
specified in the relevant clause of the guideline document, the meter should
record in addition the following parameters and all these parameters as well as
the displayed parameters should be retrievable/calculable at the BCS end
through CMRI/HHU/LAPTOP through an additional and separate retrievable
mode (i.e. other than the standard DLMS data downloading mode):
1.
Bill Point TOD Reactive Energies (Kvarh) Lag & Lead
2.
Current TOD Reactive Energies (Kvarh) Lag & Lead
3.
Current Maximum Demand (KVA) ( 0 –24 HRS)
4.
Instantaneous power factors of individual phases
5.
Bill Point Power factors of individual phases
6.
Detail Tamper information
7.
Detail historical data of all the parameters for at least 6 calendar months
8.
Information regarding following failures:
a) Time & Calendar
b) RTC battery
c) Segment failure.
d) Self diagnostic details
e) Battery bad flag
Note:- If for any reason a separate data downloading mode (i.e. other than the
standard DLMS data downloading) cannot be provided or impossible to be
implemented, then six months historical backup of energy and demand
recordings of the meter should be made available in the push button display of
the meter.
b) Sub-station feeder and DTR meters
The standard parameters as specified in the relevant clause of the guideline
document shall be displayed in the auto display mode. Additional parameters if
required for the push button mode and BCS mode will be notified in due course
prior to ordering. However in addition to the daily accounting data, monthly or
other periodic figures should also be available.
21.
CALIBRATION & TEST OUTPUT
21.1 All the meters shall be tested, calibrated and sealed at works before
dispatch. Further, no modification of calibration shall be possible at site by any
means.
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However, it shall be possible to check the accuracy of energy measurement of the
meter while in operation in the field by means of LED test output on meter,
accessible from the front as well as through high-resolution display using suitable
test equipment. Resolution of the test output shall be sufficient to enable the
starting current test in less than 10 minutes.
Test output device shall be provided in the form of preferably one common LED
for KWh & KVARh or two separate LEDs, for the provision of selecting the
parameter being tested. The test output device should have constant pulse rate in
terms of pulse/unit energy.
22.
REAL TIME INTERNAL CLOCK (RTC)
22.1. RTC shall be pre-programmed for 30 Years day/date without any necessity
for correction. The maximum drift shall not exceed +/- 180 Seconds per year. The
uncertainty of setting initial time shall not exceed + 30 Seconds with respect to
Indian standard time (Ref. NPL New Delhi).
The clock day/date setting and synchronization shall only be possible through
password/Key code command from one of the following:
a) Hand Held Unit (HHU) or Meter testing work bench and this shall need password
enabling for meter;
b) From remote server through suitable communication network or Sub-station data logger
‗PC‘
23.
.
DEMAND INTEGRATION & MD REGISTRATION
24.
23.1. The meter shall continuously monitor and calculate maximum demand for
each interval of time, which may be programmable as a block of 15 minutes or
30 minutes as per the user‘s choice through the communicating ports as and
when required with proper password identification & authentication. At the end of
every demand integration period the new calculated MD shall be compared with
the previous MD and meter shall store whichever value is higher with date & time
stamping. Under the current integration period, the rising demand should be
displayed continuously along with the elapsed time. The rising demand with the
elapsed time should be held in the memory in the event of interruption or
switching off supply and it should not become zero on such instances. The
registered demand and the number of times the MD is reset shall also be
displayed and the information stored.
23.2. The display of Maximum demand should be as per the provision G-6 of IS
14697 : 1999
MD RESET
It should also be possible to reset the MD using options. The meter shall have any of
the following MD resetting options:
24.1
Automatic reset at the end of a certain predefined period by default (24:00
hrs of the last day of the month).
24.2
Resetting through a hand held terminal capable of communicating with
the meter (i.e. through HHU with proper password identification & authentication).
24.3
Communication driven reset form the base terminal/server with proper
password identification and authentication.
24.4
Note:- It should not be possible to reset the MD by the use of the
local push button.
25.
ELECTROMAGNETIC COMPATIBILITY
The static energy meters shall conform to requirements listed in relevant standards and
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shall also be protected against radiated interference from either magnetic or radiofrequency source.
a.
IMMUNITY TO ELECTROMAGNETIC DISTURBANCE
The meter shall be designed in such a way that conducted or radiated
electromagnetic disturbance as well as electrostatic discharge do not damage or
substantially influence the meter and meter shall work satisfactorily under these
conditions as per relevant standards
NOTE: the disturbances to be considered are: (a)
Harmonics
(b)
Voltage dips and short interruptions
(c)
Conducted transients
(d)
D.C. and A.C. magnetic fields
(e)
Electromagnetic HF fields
(f)
Electrostatic discharges (ESD)
b.
RADIO INTERFERENCE SUPPRESSIONS
The meter shall not generate noise, which could interfere with other equipment, and
meter shall work satisfactorily as per relevant standard
26.
TAMPER & FRAUD MONITORING FEATURES
The meter shall work satisfactorily under presence of various influencing conditions like
External Magnetic Field, Electromagnetic Field, Radio Frequency Interference,
Vibrations, harmonic Distortion, Voltage/Frequency Fluctuations, and electromagnetic
High Frequency Fields etc. The meter shall be immune to abnormal voltage/frequency
generating devices and shall record the occurrence and restoration of such tamper
events along with parameters such as current, voltages, kWh, power factor, event code,
date & time etc. (listed in Table A6.1 to A6.8 in the guideline document).
Tamper details shall be stored in internal memory for retrieval by authorized personnel
through either of the following:
i)
HHU.
ii) Remote access through suitable communication network.
Minimum 250 numbers of events (occurrences & restoration with date & time) should
be available in the meter memory.
The meter shall function properly under following common abnormal conditions:
1. Phase
The meter shall keep working accurately irrespective of
sequence
the phase sequence of the supply.
reversal
2. Missing
Neutral
The meter shall continue to record accurately according to
electrical connections even if the Neutral of potential
supply is accidentally or incidentally disconnected.
3. Current
reversal / CT
polarity
reversal
The meter shall log energy in forward direction even if the
current is flowing in reverse direction in one or more
phases. The meter shall also be capable of detecting and
recording occurrence and restoration with date and time if
the current is flowing in reverse direction in one or more
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phases.
4. External
magnetic
influence
The metering system shall be provided with adequate
magnetic shielding so that any external magnetic field (AC
Electro Magnet or DC Magnet) as per the values specified
in CBIP Technical Report No.88 (with latest amendments)
applied on the metering system shall not affect the proper
functioning and recording of energy as per error limits
prescribed by CBIP.
Beside this the meter should have features to detect the occurrence and restoration of,
at least, the following common abnormal events:
a) Missing Potential & Potential imbalance: The meter shall be capable of
detecting and recording occurrence and restoration with date and time the
cases of Potential failure which could happen due to disconnection of
potential leads (one or two), failure of phase line fuse from the Transformer
primary side. Meter shall also detect and log cases of voltage unbalance
(from 5 % for more than 5 minutes or more- programmable) of voltages.
b) Voltage High / Voltage Low: In case the average 3 phase voltage remains
less (below 0.75Vref by default) or more (above 1.15Vref by default) for a
predefined period (15 minutes by default), the meter shall log such
incidences with date & time. The voltage thresholds & persistence time shall
be programmable using the CMRI & BCS. This abnormal condition shall be
logged only when all the three-phase voltage is available.
c) Current imbalance: The meter shall be capable of detecting and recording
occurrence and restoration with date and time of Current unbalance (30% or
more for more than 15 minutes- programmable).
d) Current Circuit Short: The meter shall be capable of detecting and
recording occurrences and restoration of shorting of any one or two phases
of current circuit to identify events like CT saturation, CT lead shorting, CT
inter turns short etc.
e) Current Circuit Open: The meter shall be capable of detecting and
recording occurrences and restoration of opening of any one or two phases
of current circuit which can happen due to intentional / accidental
disconnection of current circuits. The meter shall be able to log abnormality
conditions in current open event like CT leads burns, loose connection, CT
winding open etc in the meter memory. No load condition should not be
recorded in meter memory as a Current circuit open event.
f) Power on/off: The meter shall be capable to record power on /off events in
the meter memory. All potential failure should be record as power off event.
g) High Neutral Current: The meter shall be capable of recording incidences of
excess neutral current (if In is in excess of x % of Ib – programmable) .The
limits shall be define by the purchaser during the time of final supply.
h) Over load/ low load Hours: The meter shall be capable of recording the
over load / low load hours in KVA in the meter memory. The over loads limit
shall be in terms of % of Transformer rating in KVA (programmable using
HHU & BCS). The over load limits shall be define by the purchaser during the
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time of final supply.
i) The meter shall also be capable to withstand and shall not get damaged if
phase-to-phase voltage is applied between phases to neutral for 10 minutes
The meter shall record the total duration of the above abnormalities, time and date of
their occurrences & restorations with a snap shot of electrical conditions viz. Voltage,
current, kwh energy, PF etc.
Logic for calculation of voltage and current imbalance shall be furnished by the
tenderer.
The meter shall keep records for the minimum last 250 events (occurrence +
restoration) for above of abnormal conditions. It shall be possible to retrieve the
abnormal event data along with all related snap- shots' data through the meter's optical
port or through radio with the help of a hand held unit (HHU) and download the same to
the BCS where it shall be available for viewing. All this information shall be made
available in simple and easily understandable format.
The above shall be selectable and will be in line with Table A6.8 of GUIDELINE
DOCUMENT: Data Exchange for Electricity Meter Reading, Tariff and Load Control –
Companion Specification.
Note: DLMS guideline document should be followed as far as DLMS compatibility of the
meter data and communication is concerned. Any additional features asked for in the
TS are to be available for viewing (in the display if specifically asked for) and in the
manufacturer specific BCS to be supplied along with. Programmability features related
to persistence time and threshold values not supported by DLMS may be ignored.
27.
TAMPER LOGIC
Properly designed meter event logic should be provided. There shall be separate
compartments for logging of potential related event, current related event and power on/off
event. The bidder should explain the events details in each compartment under their offer.
The logging of various events in each compartment should be as under:
Once one or more compartments have become full, the last event pertaining to the same
compartment will be entered and the earliest (first one)-event should disappear. Thus, in this
manner each succeeding event will replace the earliest recorded event, compartment wise.
Events of one compartment/category should overwrite the events of their own
compartment/category only.
Properly defined meter tamper logic should be provided. The tamper logic should be
capable of discriminating the system abnormalities from source side and load side and
it should not log/record tamper due to source side abnormalities.
There shall be separate compartments for logging of different types of tampers/events
as follows:
Compartment No. 1:
40 % of the tamper memory space shall be allocated for the following current
related tampers
- CT polarity reversal
- CT open circuit
- CT short (bypass)
Current unbalance
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Compartment No. 2:
35 % of the tamper memory space shall be allocated for potential related
tampers including power failure events.
Compartment No. 3-7:
25 % of the tamper memory space shall be allocated for other events.
28.
BILLING HISTORY & LOAD SURVEY
The meter shall have sufficient non-volatile memory for recording history of energy
parameters for minimum last six billing cycles (Bill date shall be 00 hrs of the 1st date of
the calendar month by default – programmable) and information should be made
available at the BCS end.
Load survey parameters and data set required for different categories will be made
known in due course after consultation with the bidders before ordering. It will be based
on the guideline document. Load survey should be of 45 days with 30 minutes demand
integration period.
These load survey and history data can be retrieved with the help of Meter Reading
Instrument on local interrogation or remotely using the remote communication interface.
The above load survey data should be available in the form of bar charts as well as in
spreadsheets. The BCS shall have the facility to give complete load survey data both in
numeric and graphic form.
29.
TOD METERING PROVISIONS
There shall be a provision up to three Time of Day Zones for Energy (active import,
reactive lag while active import & apparent import) and Demand (Apparent demand)
registers. TOD provision shall however be as per the guideline document with
maximum script identifiers (16) for energy and demand for future use. However at
present only three time zones will be used : 06:00 Hrs to 17:00 Hrs, 17:00 Hrs to 22:00
Hrs and 22:00 Hrs to 06:00 Hrs. Number and timing of these TOD Zones shall be user
programmable with proper security system.
30.
HARMONICS MEASUREMENT
THD up to 29th Harmonic shall be measurable that is at sampling rate of 3000/sec. The
meter should be capable of measuring fundamental energy as well as total energy.
Fundamental energy shall be made available on meter-display and the same only shall
be used for billing purpose.
The total energy shall be logged in the meter memory and be capable of down loading
to the BCS through HHU as well as through the remote communication port and be
available for analysis at the BCS end.
Note: DLMS guideline document should be followed as far as DLMS compatibility of the
meter data and communication is concerned. Any additional features asked for in the
TS are to be available for viewing (in the display if specifically asked for) and in the
manufacturer specific BCS to be supplied along with. For example total energy is to be
used as the billing parameter as per DLMS. However fundamental energy is required to
be available in the display or be downloadable in the manufacturer specific BCS.
31.
SELF DIAGNOSTIC FEATURE
The meter shall be capable of performing complete self-diagnostic check to monitor the
circuits for any malfunctioning to ensure integrity of data memory location at all time.
The meter shall have indication for unsatisfactory/non-functioning/malfunctioning of the
following:
a) Time and date on meter display
b) All display segments on meter display
c) Real Time Clock (RTC) status in meter reading prints out at BCS end
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d) Non-volatile Memory (NVM) status in meter reading prints out at BCS end.
e) While installing the meter, it should be possible to check the correctness of
Current Transformer, Voltage connections to the meter and their polarity from
the functioning of the meter for different voltage injections with the help of
vector/phasor diagrams. It should also be possible to check the current and
voltage sequence parity. For this purpose suitable software for field diagnosis of
meter connections with the help of HHU/Meter Reading Instrument should be
supplied.
Note: Features not supported by DLMS should be available in the manufacturer
specific BCS.
32.
OTHER SALIENT FEATURES OF METERS
a) It should be possible to check the healthiness of phase voltages by displaying all the
voltages on the meter display.
b) The meter must be readable in power off condition. For that a battery back-up
of suitable capacity shall be provided. Push button for the normal display
shall also be used for battery back-up display in power off condition for the
manual mode reading of the auto display parameters. It must be possible to
power up the battery by means of an external source or by the HHU itself for
reading the meter in power off condition by the HHU. In case of an external
source an inductive coupling arrangement shall be provided so that it should
not be possible to damage the circuit of the meter by applying excess voltage
directly in the meter.
c) The meter should work accurately irrespective of phase sequence of the
mains supply
d) The meter should remain powered up and functional even when either of the
two phases or one phase along with neutral is available to meter.
e) The meter should continue to record accurately as per prevailing electrical
conditions even if the neutral of the potential supply gets disconnected.
33.
TEST AND TEST CONDITIONS
Unless specifically waived off, all tests shall be witnessed by the purchaser.
33.1.1. The Energy meter offered shall be fully type tested at any of the NABL
accredited test laboratories as per standards indicated in Clause 5 above. That is
the meter offered should have successfully passed all type tests described in the
IS 14697 and the meter Data Transfer and Communication capability as per the
guideline document.
33.1.2. One (1) out of every one thousand (1000) meters or part thereof
shall be subjected to the complete range of type tests after final
assembly. In case of any failure to pass all specified tests, the bidder
shall arrange to carry out the requisite modifications/replacements in
the entire lot of meters at his own cost. After any such modifications
and final assembly, two (2) meters selected out of the lot by the
Owner's representative shall be subjected to the full range of type tests.
The Owner shall accept the lot only after successful type testing.
33.1.3. Further Purchaser shall reserve the right to pick up energy meters at
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random from the lots offered and get the meter tested at third party lab i.e. CPRI /
agencies listed at Appendix-C of CBIP publication No-304 / NPL / CQAL/ ERTL /
ERDA at the sole discretion of the Purchaser. The supplier has no right to contest
the test results of the third party lab or for additional test and has to replace/take
corrective action at the cost of the supplier
33.1.4..It shall be the responsibility of the supplier to arrange such tests and
Purchaser shall be informed of the date and time of conduction of tests well in
advance to enable him to witness such tests. Test charges of the testing authority,
for such successful repeat type tests, shall be reimbursed at actual by the
Purchaser.
33.1.5. The meters used for type testing shall be separately identified,
duly marked, and supplied to the Owner in case they are fully functional
and as good as other (new) meters, after necessary touching
up/refurbishing. In case this is not possible, the bidder shall provide
their replacements at no extra cost to Owner.
33.1.6
The Bidder shall arrange all type te sting specified above, and
bear all expenses for the same.
Type test certificate shall be submitted along with the offer and the same shall
not be more than 36 months old at the time of bid submission. Make & type of
major components used in the type-tested meter shall be indicated in the QAP.
33.2. Acceptance Test
33.2.1. All acceptance tests as per relevant standards shall be carried out in the
presence of utility representatives.
33.2..2. Additional acceptance shall include Surge withstand (SWC) for 6 kVp, as
per IEC 62052-11, Lightning impulse test and HF disturbance test as IS 14697.
One sample meter per order from one of the offered lot shall be subjected to
SWC/other semi-destructive tests. Meters after tests shall not be used.
33.2..3. Accuracy tests shall be performed at the beginning and at the end of the
acceptance tests specified.
33.3
Routine Test
33.3.1. All routine tests as specified in table 18 of CBIP Technical Report No. 88
shall be carried out on each individual meter and routine tests certificates shall
be submitted for approval of purchaser.
34.
QUALITY ASSURANCE:
34.1. The manufacturer shall have a comprehensive quality assurance program at all
stages of manufacture for ensuring products giving reliable, trouble free performance.
Details of the bidder‘s quality assurance and test set up shall be furnished with the
bid. A detailed quality assurance program shall be finalized with the successful bidder
during the award stage. Bidder shall furnish following information along with his bid:
i)
Organization structure of the manufacturer and his main sub-suppliers (PCBs,
SMT cards, CT/PT) with details of ‗QA‘ setup, overall workflow;
ii) Copy of system manual showing ‗QAP‘ (Quality Assurance Plan) as actually
practiced during manufacturing and final testing.
iii) List of raw materials and critical components (ASIC chip, crystal clock, memory
register Chip, transformers, optical ports etc.) with their suppliers;
iv) Stage inspection of product before final testing;
v) Procedure adopted for ‗In-situ‘ testing of PCBs, after placement of surface
mounted component, for quantitative parametric variation of tolerance by self or
sub-contractor.
vi) Testing and calibration facility, date of calibration of test bench, manpower data
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of bench operators;
vii) Sample copies of test certificate of bought out components.
35.
GUARANTEE
35.1. Equipment (Meter) supplied shall be guaranteed for a period of 66 months from
the date of supply or 60 months from the date of installation, whichever is earlier.
Bidders shall guarantee to repair or replace the meters and meter boxes and other
accessories, which are found to be defective/ inoperative at the time of installation, or
become inoperative/ defective during guarantee period. Replacements shall be
effected within 1 month from the date of intimation.
The bidder shall extend the guarantee of 5 years. However the backup bank
guarantee provided by the bidders shall be valid for 2 years only.
36. FIXING & CONNECTION ARRANGEMENT
Manufacturer shall ensure following technical points:
i)
Meter shall be suitable for mounting on Simplex type vertical panel with front
door; CAT-M4 disconnecting type TBs to be used for Current circuit; Panel
wiring to be properly dressed and harnessed; External cables to enter panel
from bottom gland plate using double compression glands.
ii)
Meter installation and inter-connection from existing CT/PT connections
to energy meters in the panel shall be in the scope of contractor/bidder.
iii) Energy Meter terminals block shall be adequately sized with regard to
maximum conductor dimension, commensurate with current rating of Energy
Meter.
37. SOFTWARE
37.1.
Licensed copies of the relevant software shall be made available for
installation on each Hand Held Unit (HHU) /Common Meter Reading
Instrument (CMRI) and Base computer software (BCS) for installation on the
server and other terminals by the supplier.
HHU/Common Meter Reading Instrument (CMRI) would be loaded with userfriendly software (windows based) for reading, downloading meter data and
relevant programming transaction in the meter with proper security system.
37.2.
Windows based user interactive Base Computer Software (BCS) shall
have to be supplied for efficient and speedy recovery of data from
HHU/CMRI/Meter(by remote communication) and downloading instructions
from base computer software to HHU/CMRI/Meter(by remote communication).
This BCS should have, amongst other requirements, features and
facilities to communicate, download and display meter data as described
in the “Guideline document – Data Exchange for Electricity Meter
Reading, Tariff and Load Control (Companion Specification for IEC 62056
series of Standards)” from DLMS/COSEM meters. The BCS should also
have facility to convert meter reading data into user definable DBF (Access)
and spreadsheet format for integrating with the purchaser's billing system.
Here again an "Export wizard" or similar utility shall be available whereby user
can select file format, the variable data to export, the field width selection of
each variable so that it may be possible for the user to integrate the same with
the user‘s billing data and process the selected data in desired manner. The
BCS shall also allow for viewing and easy analysis of the meter data acquired
and for exporting that data in ASCII or CSV format. It should have in general
the following features:
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i)
ii)
iii)
iv)
v)
vi)
It shall allow collecting of meter data on direct communication with the meter
through wires as well as through remote system.
It shall be possible to view the meter data and details in user friendly manner
(Windows Based Platform).
New users with their level of access rights could be defined and managed by
supervisors based upon their usage requirement.
It shall be possible to maintain a meter information database, to add, edit, delete
meters from the meter information database with proper authentication. The
meter information database shall have amongst others the information relating to
meter serial no, meter location, meter status, CT, PT ratios, KVA ratings etc.
BCS must have provision to manage users and roles. It shall be possible to
create a user and assign him privileges to perform specific types of operation
according to the ―Role‖ assigned to him. It shall be possible to define a role and
link it with ―Rights‖ of using different options. If rights are not assigned for a
particular option, a ―User‖ with that ―Role‖ shall have no right to use or view that
option.
The software must have the user friendly GUI and User Interface should be
customisable by the user. It shall be possible for a user to
a) Display or hide a column in the Meter List Pane
b) Change the column width
c) Activate & apply column wise filter for displayed list
d) Sort the order of the displayed list. The sorting can be enabled on any of the
displayed field / column
e) Group the meter list according to a field displayed in a column and then
further sub-group the list according to another field
37.3. The software‘s shall have the flexibility to generate at least the following
sets of reports amongst others




Energy Accounting reports
Billing Point reports
Load survey reports
Tamper information reports
37.4. Billing reports to include customer ID, Name & Address, connected Load,
meter status, billing cycle, historical meter reading, date and time, current
meter reading, date and time, Maximum Demand, date and time of Maximum
Demand occurrence
37.5. .Load survey report for a pre determined time i.e. from ________ date to
___________ date, to include the following.
Customer ID, meter number, Consumer Connectivity references i.e. identity &
location of pole / Distribution transformer reference, feeder reference, subdivision reference, division reference, circle reference, time, date, maximum
demand (kW),KVAR, kWh, power factor, kVAh, MD reset count, power on
hours, outage duration, number of outages, Voltages max R, Y, B date time
and duration, Voltages minimum R, Y, B date time and duration, load factor as
(energy consumed/(maximum demand x power on hours)), average load as
(energy consumed / power on hours), TOD max DEMAND and duration,
Average current phase wise.
37.6. The load survey data should be available in the form of bar charts as well
as in spreadsheets. The BCS shall have the facility to give complete load
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Technical Specification
survey data both in numeric and graphic form. The exact parameters set and
the period for the load survey report for each category of meters will be
specified in due course after consultation with the bidders prior to ordering.
37.7. Tamper reports to include for a pre determined duration or month wise,
tamper count, tamper duration and tamper history for each of the meters.
37.8. Bidder will provide soft copy of all the software in CD form along with the
meters supplied.
37.9. Bidder to install & demonstrate working of software programmes on the
HHU/CMRI‘s of APDCL
a) Base computer station software for accepting data from hand held unit/CMRI/
for Processing, generating reports and downloading instructions from the
BCS to HHU/CMRI for onward transmission to DLMS/COSEM meters of
specific makes..
b) Dial-up software for accepting data from the meter by remote communication means
to the BCS, processing data, & generating reports.
38. SOFTWARE SECURITY
The BCS shall have multilevel password for data protection and security. The first level shall
allow the user to enter the system. The different software features shall be protected by
different passwords. The configurable of passwords shall be user definable. The
software installed on one PC shall not be copied on another PC without additional
security.
39. HELP SYSTEM
Exhaustive online & offline help shall be an integral part of the software so that user can use all
the features of the software by pulling down the help contents from the user friendly
menus for any references.
40. DATA SECURITY
In addition to the basic security, selective advanced security with encryption and authentication
by the use of NIST SP 800-38D as specified in the companion standard guideline
document must be provided for.
The security system must be adequate enough not to allow data manipulation at any stage.
The system should be able to achieve security through authenticated transaction on the
HHU/CMRI form the back office software only.
Compatibility of the meter for any relevant security system to be developed by the SI for proper
data protection is an essential requirement. For further elaboration, clause 7 of the
Guideline Document related Association and Data Security may be seen.
41. Conformance Testing :Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
All the categories of meter are required to comply strictly with the Conformance Testing
clause as detailed out in Annexure A of the Guideline Document. Conformance test
certificates are to be provided with the sample meters.
GUARANTEED TECHNICAL PARTICULARS FOR 3 PHASE 4 WIRE CT/CT PT OPERATED
TRIVECTOR ENERGY METER
Sl.
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Item
Bidder‟s data
Type of Meter
Application
Standard to which the meter
confirm
Rated Voltage
Rated Current
Frequency
Overload capacity
Minimum starting current in % of
base current
Power Factor Range
Power loss in potential circuit
Power loss in current circuit
Change in error due to
a. Variation in frequency
b. Variation in temperature
c. Variation in voltage
Accuracy Class
Type of Energy Registration
Mechanism.
MD Reset Mechanism
Dynamic Working range
a) Voltage
b) Current
Type of load (linear, non linear,
balanced /unbalanced at any
P.F.)
Total Weight of meter
Dimension of the meter
Details of meter base & cover
Terminal Cover details
Capability for fraud Prevention &
detection
Sealing and Locking Arrangement
Display details
i. Display Cycle (descriptive in
order of
display sequence)
auto and manual
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Technical Specification
25
26
27
28
29
30
31
32
33
34
35
ii. Period of display of each
parameter
iii. Display scroll-lock facility
iv. Backlit LCD
v. display off period between two
cycles
vI. No of digits of display and
height of character.
Memory Capacity
Non volatile memory retention
capacity
Powering on facility in absence of
mains
Tamper
data
preservation
capacity :
a) on display
b) with meter data downloading
provisions.
Tamper logic in detail
Load Survey details :
a) Parameter measured & Logged
b) Logging interval
c) No. of days of Load Survey
Time of the day Zone Provision
Type of communication:
a) Local-Optical port details
b) Additional Communication port
for AMR compatibility
Real Time Clock
Self Diagnostic Features (Provide
Details)
Certification Marks
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Technical Specification
TECHNICAL SPECIFICATION FOR LT RESIN CAST RING TYPE
CURRENT TRANSFORMER FOR OUTDOOR APPLICATION
41.0 SCOPE:
The scope covers packing, supply and delivery at destination, subsequent storage, erection
and commissioning at site (including insurance during transit and storage), of Resin cast
Ring Type LT Current transformer (CT), of accuracy class 0.5 for Distribution transformer
Metering. CT‘s should be outdoor type and suitable to be mounted on the bushing of LT
side of transformer. Suitable fixing arrangement to mount the CT on the transformer‘s
bushing shall be provided with each CT. Current Transformers are required for 25 KVA TO
1000 KVA‘s distribution transformers.
41.1
APPLICABLE STANDARDS:
IS 2705
IS 4201
IS 2629
41.2
Current Transformers specifications
Application guide for CT
Hot dip galvanizing
TYPE AND RATING OF L.T.CURRENT RANSFORMERS:
LT CTs shall be of the following type and ratings:
Sr.
Characteristics
no
Nominal system voltage
1.
Highest system voltage
2.
Insulation level (HVPF test
3.
voltage for 1 minute)
Frequency
4.
5.
Transformation ratios
6.
Type
7.
Rated output
8.
Class of accuracy
9.
Short time thermal current
10.
Rated continuous thermal
current
11.
Instrument security factor
12.
Ratio (current) error max.
13.
Phase angle error max.
14.
Temperature rise over values
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
Values
415 Volts
660 Volts
3 KV
50 Hz
100/5, 200/5,
400/5A,600/5A,800/5A, 1000/5A,
1200/5A
Ring type
5 VA (2.5VA for 100/5A)
0.5
Minimum 5 K Amp. For one
second
120% of the rated
Shall not exceed 5.
Shall not exceed the values
prescribed in IS: 2705/1992.
Shall not exceed the values
prescribed in IS: 2705/1992.
Shall not exceed the values
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Technical Specification
ambient temperature 55 deg C
at rated continuous thermal
current (1.2 Ip).
15.
Supply system variation
prescribed in IS: 2705/1992.
Voltage: 70% to 120% Vref
Frequency: 45 Hz to 55 Hz
41.3. GENERAL TECHNICAL SPECIFICATION OF RESIN CAST RING
TYPE L.T. CURRENT TRANSFORMERS:
41.3.1 Current transformer shall have an opening in the center to accommodate
a primary conductor that may be cable (with the lugs) / bus-bar / Secondary
terminal of Distribution transformer. The current transformers shall have
rated burden as 5 VA ( 2.5VA for 100/5A). The terminals should be complete
with connecting lugs.
41.3.2 Current transformers shall be of Resin cast type, suitable for outdoor
installation, class of insulation shall be ―F‖ as specified in IS:2705 made of
cyclo elephatic resin should be used for manufacturing these CTs. The
material of CT may be verified at material lab / Details of material shall be
provide .
41.3.3 For above 100/5A & above ratio CTs internal diameter of LT CT shall be
suitable to pass the cable of 120% current rating of CT and fit on bushing of
Transformer of specified ratings above.
41.3.4 The polarity marking on the offered CT primary & secondary side should
be embossed.
41.3.5 A three core (2.5sq. mm) HR FR PVC insulated flexible multi strand
copper cable shall come out directly from the CT as secondary terminal. The
length of the wire shall be around 3 Mtrs for 100/5, 200/5, 400/5 & 600/5A, 4
Mtrs for 1000/5A & above current ratings. Secondary wire shall directly
connect to the energy meter‘s terminals. Pin type lugs shall be required on
open end of cable. Proper colour coding/identification shall be used to
identify the CT & PT leads.
41.3.6 LT CTs shall be of Brick red colour
41.3.7 Type test report of same design and out door type LT CTs shall be
submitted along with the bid. One no sample of each rating is required to be
submitted along with the bid document for verification otherwise bid will be
considered non responsive.
41.3.8 CT shall be of similar design as shown in drawing attached.
41.4 TESTS:
41.4.1 ROUTINE TEST & ACCEPTANCE TEST
a. Current Transformer shall comply with and shall be subjected to all routine
tests prescribed in relevant IS: 2705/1992
b. Routine tests as per relevant standard along with accuracy test as per
clause 7.2 of IS: 2705 (Part.II)
c. All routine tests as stipulated in the relevant standards shall be carried out
and routine tests certificates shall be submitted before inspection
d. Schedule of routine & acceptance test for CT:
i. Verification of terminal marking and polarity.
ii. Determination of error according to the requirement of appropriate
accuracy class at 20% and 120% with Full and Quarter Burden.
41.4.2 Type Test
The CT offered shall be fully type tested at any of the NABL accredited test
laboratories as per relevant standards.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
41.4.3 Schedule of type test for CT (As per Reference Standard) to be
conducted and certified by NABL Certified Lab / test house:
a.
b.
c.
d.
e.
f.
41.5
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Verification of terminal marking and polarity.
High voltage power frequency test.
Over voltage inter-turn test.
Determination of error according to the requirement of appropriate
accuracy class at 5%, 20%, 100% and 120% with Full and Quarter
Burden.
Short time current test and Peak dynamic current test.
Temperature rise test
NAME PLATE AND MARKING:
The ratio, VA burden, class of accuracy, name of manufacturer / year of
manufacturing shall be printed on metallic nameplate of CT. The ratio &
polarity should be marked on the body of the LT CTs.
Self adhesive, laminated, printed label must be having following details:
R-APDRP Works
Manufacturer's name
Manufacturing month and year.
Batch No
Property of ASEB
Ratio, Burden & Accuracy Class
Applicable Standard
I.L.
STC Rating
Continuous thermal current
Caution against open secondary
Guarantee Period.
41.6 DRAWING APPROVAL:
Party must get final drawing approval before commencement of commercial
production/supply.
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Technical Specification
GUARANTEED TECHNICAL PARTICULARS FOR LT CTs
Sl.
N
1.
Type / Capacity
2.
a) Rated Voltage
Characteristics
Bidders Data
b)
c)
d)
e)
f)
3.
Highest System Voltage
Rated Primary Current
Rated Secondary Current
No. of Cores
Rated Continuous Thermal Current
temperature rise over ambient
g) One minute withstand Power
frequency Voltage
Class of Accuracy - 0.5
4.
Burden –
a) 100/5A : 2.5 VA
b) 200/5A & above 5 VA
5.
Dimension in mm
i.
Inner Dia of CT ( CT Rating wise)
ii.
Length of secondary lead 100/5A,
200/5A,400/5A, 600/5A - 3 Mtrs.
iii.
Length of secondary lead 1000/5A &
above current rating – 4 Mtrs.
6.
Material
i)
Core
ii)
Conductor
iii)
Insulation ( Class : F as per IS
2705)
Type Test Report
Conformance Standards
7.
8.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
TECHNICAL SPECIFICATION FOR SMC DTC METER BOXES
COMPRISING METER
1) SCOPE:
 This scope shall cover design, engineering, manufacture, testing at
manufacturers works before dispatch, packing, supply and delivery at
destination, subsequent storage, erection and commissioning at site
(including insurance during transit and storageof anti-corrosive, dust proof,
rust proof, shock proof, self extinguishing property, resistant to heat, vermin &
water proof, ultra violet stabilized and pilfer resistant SMC distribution
transformer meter boxes made of thermosetting plastic i.e. Glass reinforced
polyester sheet moulding compound (SMC) confirming to IS : 13410 (1992)
and attached technical specification, drawing and IS : 14772:2000.
2) CONSTRUCTION OF METER BOX:
a) The meter box shall comprise of moulded single base and doors. The
construction the box shall be of single base type. The meter box shall generally
comply with the provision of IS-14772. The boxes shall be suitable for
outdoor/indoor application. Meter box shall have minimum inside size of 450 mm
(H) X 375 mm (W) X 200 mm (D) and thickness minimum 2.0 mm as per
enclosed drawing. Colour of the box shall be off white. The thickness of the box
shall not be less than 2.0 mm on all sides including door. The top surface of
meter box shall have tapering shape for easy flow of rainwater.
b) The meter box shall have a groove all round to hold soft rubber gasket with
corresponding tongue in door to ensure tongue & groove type sealing
arrangement in addition to gasket sealing for protection against entry of dust and
water.
c) The door shall rest on the base of box in such a way that any access from
outside to the meter is not possible. The door in closed position should be
overlapped on collar of base such that direct entry of screwdriver or tool is not
possible.
d) The box shall confirm to ingress protection level IP-54
e) All corners of the meter box should be round and not pointed ones. Meter
mounting in the box shall be fitted with raised SMC sheet of 4 mm thickness so
as to facilitate mounting of the meter .
f) The box should be capable to house of LT TVM and 1 No. GSM / GPRS modem.
Door with locking and sealing arrangement should be provided.
g) Meter box cover shall be fitted to base by concealed stainless steel strip hinges.
The SMC meter boxes shall be closed by S.S.‘U‘ clamp of minimum 0.8 mm (+
0.1mm) thickness for holding and locking of the door. The ―U‖ clamp shall have
4mm diameter hole through which it is possible to seal the box for sealing
purpose.
h) For meter reading the box should have a window with toughened/triplex glass
fixed with S.S. frame from inside. The box should have a window of size 140mm
X 120mm provided with glass as shown in the drawing.
i) For CT secondary PT supply cable entry 1 Nos. hole having diameter of
minimum 19mm shall be provided on bottom of box with good quality polymeric
gland having diameter of minimum 19mm as shown in the drawing.
j) One no. earth bolt of 6mm diameter x 25mm length with 2 number nuts and 2
nos. washers plus a spring washer shall be provided. The earthing arrangement
shall be of M.S. with zinc passivated. Earthing symbol is to be provided near the
earthing bolt.
k) All metal parts shall be zinc passivated if not mentioned specifically.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
l) The meter door shall accommodate the 9-pin D type male connector of the cable
used for interface between meter and HHU/CMRI as defined in class 4.2.1 of
CBIP technical report no 88. This cable will have meter optical sensor
terminating at the other end of the cable and permanently fixed to the optical port
of the meter. The nine pin D type mail connector should be provided with a
suitable sealable cap. For downloading data from meter through CMRI the
operator has to break the seal of the cap, remove the cap download the data put
back the cap and again seal the cap properly. This arrangement is provided to
ensure that data stored in NVM is downloaded from the door of meter box
without opening the door of the meter box and physically approaching the meter
m) Similarly the RS-485 port should also be brought on the cover of the door with
the proper sealing arrangement
n) Printing: Metallic/engraved label containing the letters R-APDRP, Circle Name and the
PO no and date shall be engraved/embossed on the top cover of the box. The name of
manufacturer shall be engraved/embossed on the bottom half of the box. A blank sticker
shall also be pasted on the
o)
meter box for use of field staff to indicate service no. etc. The front cover shall be
embossed with following Notice:
Property of APDCL
Breaking of Seals or any Tempering
With Meter is a Cognizable Offence
p) The fixing arrangements shall not be complex and it shall be easily approachable for
connections when the door is open and is completely tamper resistant once it is sealed.
q) The box shall be robust and sufficient space for convenience in metering with adequate
space for meter and proper arrangement for fixing up of communication modem (AMR
compatibility provision).
r) The dimensional drawing giving details of the meter box shall be enclosed with the bid.
3)
4)
5)
6)
7)
8)
9)
GUARANTEED TECHNICAL PARTICULARS:
Guaranteed technical particulars are given in enclosed annexure bidder shall submit
the data in given Performa.
INSPECTION AND TESTING
The bidder has to offer the boxes for inspection at his works before dispatch. The
manufacture will offer all facilities to inspectors without any charge.
DESPATCH
The SMC meter boxes shall be so dispatched as to ensure that no damage occurs
during transport where they may be subject to rough handling.
TYPE TEST CERTIFICATE:
The bidder shall submit type test report as per IS-144772-2000 & IS-13410 : 1992
from CIPET, Ahmedabad/ ERDA, Baroda along with the offer. Type test certificate
should not be older than 3 years as on the date of tender opening.
TYPE TEST
Type test report as per requirement of this specification shall be furnished before
commencement of supply
RAW MATERIALS
The manufacturer has to submit the test certificate for the material used in the lot
offered and document for purchase of raw material.
ROUTINE TEST:
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Technical Specification
Manufacturer has to carryout routine test during production to check the essential
requirements which are likely to vary during production. Manufacturer has to keep
records of the same and to be produced for verification of inspector when asked at
the time of inspection of lot.
10)
ACCEPTANCE TEST: The acceptance tests shall be carried out on randomly
selected samples.
11)
FACILITY
The bidder shall have facility to test the box for routine tests and acceptances as
per IS-14772:2000 and IS-13410 at their works. The bidder has to submit list of
machinery & equipment/testing instrument etc.
12) TENDER SAMPLE
A sample as per specifications will have to be submitted for approval.
13. Pilfer Proof Box Tests
Type Tests:
The following tests are to be conducted on the pilfer proof box at an NABL
accredited laboratory.
I.
II.
III.
IV.
V.
Test of material identification
Test for mechanical strength as per IS 5133
Test for water absorption as per IS 5133
Test for stability at high temperature as per IS 5133
Test for withstanding temperature of boiling water for 5 minutes continuously for
non-distortion or softening of material.
VI. Glow wire test at 650oC as per clause 5.2.4 of CBIP Technical Report No.88 read
with amendments.
Acceptance and Routine Tests:
a) Acceptance Tests:
The following shall constitute acceptance test for box.
i. Physical verification of dimensions of the box.
ii. Compatibility of the box for housing the meter for ensuring ease of
connections and reading the meter.
b) Routine Tests
i. Routine test certificates as per relevant standards shall be furnished for
approval.
ii. Physical verification
Sd/Chief General Manager (Material):APDCL
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Technical Specification
GUARANTEED TECHNICAL PARTICULARS OF BOX
Sr.
No.
1
2
3
4
5
6
7
8
9.
10
11
12
PARTICULARS
METER BOX
DETAILED PARTICULARS
TO BE
OFFERED BY
BIDDER
Maker‘s name
Material
To be intimated by the supplier
Glass reinforced polyester sheet
moulding compound
Grade of material
SMC confirming to IS:13410:1992 grade
S1
Properties of material of construction of meter box
Flame retardant
As per IS-11731 (Min FV0)
test
Exposure to flame
Self-extinguishing
(ref std IS:4249)
Degree of
IP-53 as per IS-12063/87
protection
Heat distortion
1500C (min) as per IS:13411
temp.
Inside dimension of To be mentioned by the supplier
meter box
a. height
450 mm (min)
b. width
375 mm (min)
c. depth
200 mm (min)
d. thickness
02 mm (min)
Earthing
arrangement
Earthing bolt
One no. of earthing bolt of MS with 2
nuts and 2 washers shall be provided
on RH side of box. Earthing sign has to
be provided near to earthing bolt.
Dia & length of
Dia 6 mm length 25 mm
earthing bolts
Locking
For holding & locking of door with base
arrangement
two nos (min.) of ―U‖ shaped clamps to
be provided
Sealing
Holes for wire seal
arrangement
Cable entry holes
Cable entry holes 1 nos with minimum 0
19MM polymeric gland on bottom of the
box.
Colour of box
Off white
Window having
Window size 140mm X 120 mm
triplex glass
Fixing of glass
Fitted from inside in such a way that it
can not be replaced without opening
door (with S.S. frame all around)
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
SECTION - 5
SPECIFICATION OF POLY CARBONATE SEALS REQUIRED FOR SEALING METERS &
METERING SYSTEM
5.01
Seal should be made of polycarbonate with ultra violet additive & should not be
affected by boiling water, muriatic acid.
5.02
The seal should withstand temperature up to 147  C.
5.03
Seal should be available in Clear / Red / Blue / Yellow / Amber / Green / Grey
colour and should be transparent.
5.04
Every seal should have 6 ― twisted strand stainless steel wire.
5.05
Seal should have facility to print mono gram / name of company
5.06
Every Seals should have a unique seven-digit number. Numbers shall be printed
on seal including the anchor cap-using laser marking which shall not be erased
using any tool or by any chemical reaction. Both the seven digit seal numbers
should be visible separately after closing the seal.
5.07
Seals should have tamper proof, internal ― anchor ― locking mechanism that
permanently secures the wire upon closing. The mechanism should be designed
in such a way that its original position can‘t be restored after any effort of tamper
or breaking of seals
5.08
Sealing mechanism shall be designed in such a way that it can be sealed without
using any pliers or tools.
5.09
Seal should be constructed of two parts, first the main body ( female type)&
second the anchor (male type) having locking mechanism. Both the part should
be designed in such a way that once the seal is closed the two parts can‘t be
separated.
5.10
Seal should be patented. Copy of patent shall be submitted along with offer.
5.11
Packaging: Seals shall be supplied in packet of 100 seals. Each packet shall be
labeled for following information
 Client Name
 Purchase order number &date
 Serial number range in the form of bar coding.
5.12
Seals shall be provided with tracking & recording software. The software shall
have following features

Software should have facility of defining the system controller

Facility to enter serial number of seals with the help of bar code scanner.

Receiving of seal in the system and with authentication like signature.

Facility to identify the concern who is responsible for receiving of seals
and nominated by system supervisor.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification

Provision to define different type of seals for various uses.

Software should have facility of report generation for inventory & issue
records.

Facility to track for relevant data for individual seal entered in the system.
Bidding Document for Part-B, R-APDRP, Version-1, May‟ 2012
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Technical Specification
SPECIFICATION FOR HT COMBINED CT- PT SETS FOR 3P 4W METERING
Combined 3 element CT-PT sets of specified PT and CT ratios of accuracy class
0.2S, earthed neutral shall be supplied for high tension 3 phase 4 wire metering with
AMR compatibility for R-APDRP projects. The combined sets are to be supplied with
metering
cabinet of specified design along with other necessary accessories for
installation and
commissioning of the complete metering system for Ring Fencing
Metering under the projects.
The schematic diagram of the metering system with approximate dimensions are
enclosed for ready reference. The core construction material for the metering
cabinet may be same as that of the LT metering cabinet or MS steel of 18 gauze,
properly coated with anti-corrosive paints.
1. APPLICABLE STANDARDS:
IS 3156 Part 1 &
2
IS 2629
Voltage Transformers specifications
Hot dip galvanizing
2. GENERAL TECHNICAL REQUIREMENT:
Rated Voltage
:
Rated Secondary Ct (I Basic)
33 kV/110 V & 11 kV/110 V as per requirement
:
-/5 & -/1A as per requirement specified
Rated Frequency
:
50 Hz.
Rated Burden
:
CT burden-15 VA, PT burden- 50 VA
Accuracy class
:
0.2S
Power Factor
:
Unity to Zero (all power factor lag / or lead).
Temperature
:
The standard reference ambient temperature for
Performance shall be 40 °C.
Supply system variation
:
Voltage Vref 70% to 120%
Frequency
:
45 Hz to 55 Hz
Highest system voltage
system
:
12 kV for 11 kV system and 36 kV for 33 kV
Current Transformer Ratio
25/1A,
:
15/5A, 25/5A, 50/5A, 100/5A, 200/5A, 15/1A,
50/1A, 100/1A as per specified requirement
3. GENERAL CONSTRUCTIONAL REQUIREMENT
a) The combined sets are to be of single ratio.
b) In the primary studs terminal clamps suitable for Raccon conductors
should be provided.
c) Insulation cap in HT primary bushings and conductors should be
provided with self locking system and sealing facility. Cap opening
towards the conductor shall be extended by atleast 20 cms so that the
insulation of the connecting conductor goes inside by atleast 10 cms,
d) No HT fuses are to be provided in the sets.
e) Arcing horns are not required in the sets.
f) Pressure valve is to be provided in the main tank.
g) Secondary terminal box has to be provided with double cover sealing
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Technical Specification
provisions
h) Inspection manhole is not required in the sets.
i) Sealing provision in the top cover has to be provided.
4. RATING PLATE
Self adhesive, laminated, printed label must be having following details:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
R-APDRP Works
Manufacturer's name
Manufacturing month and year.
Batch No
Property of ASEB
Ratio, Burden & Accuracy Class
Applicable Standard
I.L.
STC Rating
Continuous thermal current
Caution against open secondary
Guarantee Period.
5. DRAWING APPROVAL:
Party must get final drawing approval before commencement of commercial
production/supply.
9. TEST AND TEST CONDITIONS
Type Test
The CT offered shall be fully type tested at any of the NABL accredited test
laboratories as per relevant standards.
Routine & acceptance test
Acceptance and routine test on the sets will be conducted as per the
provisions of the relevant standards
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Technical Specification
GUARANTEED TECHNICAL PARTICULARS FOR CT- PT SETS
S.
No.
SUPPLIER‟S DATA
PARTICULARS
1.
Manufacturers Name & Address
2.
3.
Type / Capacity
a)
Rated Voltage
b)
Highest System Voltage
c)
Rated Primary
current
No. of cores
d)
Current/Secondary
e)
f)
4.
5.
Rated Output
Rated continuous Thermal Current
Temperature rise over ambient
g)
One
minute
withstand
Power
Frequency Voltage
Class of ACCURACY
Limits of current error and phase displacement
error as a percentage of the rated currents
i) 5%
ii) 20%
i) 100%
ii) 120%
6.
Material
i)
Core
ii)
iii)
Conductor
Insulation
iv)
Base
v)
No. Of CTs
7.
Secondary Termination
8.
Standard length of cable
9.
Conformance standards
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Technical Specification
GENERAL & OTHER REQUIREMENTS
1.
Meter Testing Equipment
The specified number of sets of complete equipment required for in situ functional checking and rough testing of accuracy of the meters
shall be supplied to the Purchaser. It shall include secondary v oltage
and current injection equipment (3-phase, balanced, variable power
factor), precision instruments, timing device etc., which have a sturdy
construction suitable for frequent transportation. The equipment shall
be easily portable, and shall generally comply with IEC-736, for type
and acceptance testing of Energy Meters of 0.5S/0.2S class (Table -1
of IEC 736, 1982).
In addition to the above, a test output pulse counting device, with an
accurate built-in timer, shall be provided, for independent checki ng of
Wh measurement accuracy against Owner's precision instruments.
2.
Installation and Commissioning
The static energy meters specified above shall be installed at the
premises The exact location and time -table for installation shall be
finalized by the purchaser in due course, and advised to the bidder.
The Bidder shall be responsible for total installation and
commissioning of the meters (along with test blocks, if supplied
separately) as per Owner's advice, including unpacking and
inspection on receipt at site, mounting the meters, connection of
input& output cables to the meters including any required rewiring,
functional testing, commissioning and handing over. The Bidder's
personnel shall procure/carry the necessary tools, equipment,
materials and consumables (including insulated wires, lugs, ferrules,
hardware etc.).
As a part of commissioning of BCS/HHU/CMRI, the Bidder shall load
the relevant software into the PCs at the Base computer stations and
other equipments, and fully commission the total m eter scheme as per
R-APDRP requirement. He shall also impart the necessary
instructions to Utility engineers.
Following technical information shall be furnished by the Bidders in
their offers:
i)
ii)
iii)
iv)
v)
vi)
Foreseen dimensions of proposed meter.
Expected weight of proposed meter.
Foreseen dimensions of HHU/CMRI
Expected weight of HHU/CMRI
Details of Meter testing equipment proposed to be supplied.
Dimensions and weight of the test block, if supplied separately.
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Technical Specification
3. QUALITY ASSURANCE PLAN
The bidder shall furnish the following information along with his bid; failing which
his bid shall be liable for rejection. Information shall be separately given for
individual type of material offered.
I.
The structure of Organization
II.
The duties and representatives assigned to staff ensuring Quality of work
III.
The system of purchasing, taking delivery and verification of materials
IV.
The system for ensuring quality of workmanship
V.
The quality assurance arrangements shall conform to the relevant
requirement of ISO 9001 or ISO 9002 as applicable
VI.
Statement giving list of important raw materials names of sub-suppliers for
the raw materials, list of sub-suppliers for the raw materials, list of
standards according to which the raw materials are tested. List of test
normally carried out on raw materials in presence of vendor‘s
representative, copies of test certificates.
VII.
Information and copies of test certificates as in (i) above in respect of
bought out accessories.
VIII.
List of manufacturing facilities available.
IX.
Level of automation achieved and lists of areas where manual procession
exists.
X.
List of areas in manufacturing process, where stage inspections are
normally carried out for quality control and details of such tests and
inspections.
XI.
Lists of testing equipment available with the bidder for final testing of
equipment specified and test plant limitation. If any, vis-à-vis the type,
special acceptance and routine tests specified in the relevant standards.
These limitations shall be very clearly brought out in schedule of
deviations from specified test requirements.
The vendor shall also submit following information:
iii) List of raw materials as well as bought out accessories and the names of
sub-suppliers selected from those furnished along with offers.
iv) Type test certificates of the raw materials and bought out accessories if
required by the utility.
iii) Quality Assurance Plan (QAP) withholds points for purchaser‘s inspection.
The quality assurance plan and purchasers‘ hold points shall be
discussed between the purchaser and vendor before the QAP is finalized.
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Technical Specification
4. DOCUMENTATION
4.1 All drawing shall conform to International Standards Organisation (ISO) ‗A‘ series of
drawings sheet/India Standards Specification IS: 656. All drawings shall be in ink and
suitable for microfilming. All dimensions and data shall be in S.I. Units.
4.2 List of Drawings and Documents:
The bidder shall furnish the following along with bid.
i)
Two sets of drawings showing clearly the general arrangements, fitting details,
electrical connections etc.
ii) Technical leaflets (user‘s manual) giving operating instructions.
iii) Three copies of dimensional drawings of the box for each quoted item.
4.3 The manufacturing of the equipment shall be strictly in accordance with the
approved drawings and no deviation shall be permitted without the written approval of
the purchaser. All manufacturing and fabrication work in connection with the equipment
prior to the approval of the drawing shall be at the supplier‘s risk.
4.4 Approval of drawings/work by purchaser shall not relieve the supplier of his
responsibility and liability for ensuring correctness and correct interpretation of the
drawings for meeting the specification.
4.5 The requirements of the latest revision of application standards, rules and codes of
practices The equipment shall conform in all respects to high standards of engineering,
design, workmanship and latest revisions of relevant standards at the time of orde4ring
and purchaser shall have the power to reject any work or materials which, in his
judgment is not in full accordance therewith.
4.6 The successful Bidder shall, within 2 weeks of notification of award of contract,
submit three sets of final versions of all the drawings as stipulated in the purchase
order for purchaser‘s approval. The purchaser shall communicate his
comments/approval on the drawings to the supplier within two weeks. The supplier
shall, if necessary, modify the drawings and resubmit three copies of the modified
drawings for their approval. The supplier shall within two weeks, submit 30 prints and
two good quality report copies of the approved drawings for purchaser‘s use.
4.7 Eight sets of operating manuals/technical leaflets shall be supplied to each
consignee for the first instance of supply.
4.8 One set of routine test certificates shall accompany each dispatch consignment.
4.9 The acceptance test certificates in case pre-dispatch inspection or routine test
certificates in cases where inspection is waived shall be got approved by the
purchasers.
5. INSPECTION
5.1 The inspection may be carried out by ASEB at any stage of manufacturing/
installation/ commissioning. Inspection and acceptance of any equipment under
this clause shall not relieve the bidder of his obligation of furnishing the
equipment in accordance with the specification and shall not prevent subsequent
rejection if the equipment is found to be defective.
5.2 The bidder shall keep ASEB informed in advance about the status of
manufacturing/ installation/ erection/ commissioning programme so that
arrangements can be done for inspection. The purchaser (ASEB) reserves the
right to insist for witnessing acceptance and routine tests of bought out items,
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Technical Specification
with an advance intimation of two weeks.
5.3 The purchaser (ASEB) reserves the right to get any meter/box type-tested,
from any of the lots offered for inspection received at any destination, at
purchasers‘ expense and relevant clause will apply for rejection in case of failure
to pass the tests.
5.4 The bidder shall indicate names of reputed agencies and inspection charges
for each lot/ activity clearly. The purchaser reserves the right to appoint at own
cost, any inspection agency to carryout inspection.
6. CAPACITY B