TEDAŞ-MYD/95-012.C
TURKISH ELECTRICITY DISTRIBUTION CO.
MATERIAL MANAGEMENT DEPARTMENT
TECHNICAL SPECIFICATION FOR
MV / LV DISTRIBUTION POWER TRANSFORMERS
(WITH OIL CONSERVATOR, EXPOSED TO AIR)
CONSULTANT
ELTEM-TEK
ELECTRICAL INSTALLATIONS ENGINEERING SERVICES
AND TRADE CO.
DECEMBER – 1995
MARCH – 1999 (REVISED)
FEBRUARY – 2003 (REVISED)
JANUARY – 2005 (REVISED)
TEDAŞ-MYD/95-012.C
TECHNICAL SPECIFICATION FOR
MV / LV DISTRIBUTION POWER TRANSFORMERS
(WITH OIL CONSERVATOR, EXPOSED TO AIR)
CONSENTS
1.
2.
GENERAL
1.1.
Scope
1.2.
Standards
1.3.
Service Conditions
CHARACTERISTICS
2.1.
Type
2.2.
Electrical Characteristics
2.2.1.
Rated Frequency : 50 Hz
2.2.2.
Rated Powers : 50-100-160-250-400-630-1000-1250-1600 kVA
2.2.3.
Highest System Voltages (primary) : 7,2-12-17,5-36 kV
2.2.4.
Rated Voltages
2.2.5.
Off-Load Voltage Adjustment
2.2.6.
Tapping Powers
2.2.7.
Temperature Rise
2.2.8.
Connection Symbol
2.2.9.
Impedance Voltages
2.2.10.
Short Circuit Thermal Withstand
2.2.11.
Rated Insulation Levels
2.2.12.
Sound Power Levels (LWA)
2.2.13.
Losses
2.2.14.
Operation (Loading) Mode
2.2.15.
Operation Under Overvoltage Conditions
2.2.16.
Temporary Overloading
2.2.17.
Tolerances
2.3.
Constructional Characteristics
2.3.1.
Magnetic Circuit
2.3.2.
Windings
2.3.3.
Insulation
2.3.4.
Oil Filling
2.3.5.
Tap-Changer
2.3.6.
Tank and Cover
2.3.7.
Cooling Equipment
2.3.8.
Oil-Conservator
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TEDAŞ-MYD/95-012.C
3.
4.
2.3.9.
Bushings and Terminals
2.3.10.
Cable Box
2.3.11.
Protection and Signalling Equipment
2.3.12.
Insulating Oil
2.3.13.
Arrangement of the Top Cover and Dimensions
2.3.14.
Dimensions
2.3.15.
Nameplate
2.3.16.
Anticorrosion Precautions
TESTS
3.1.
Type Tests
3.2.
Routine Tests
ACCEPTANCE TESTS AND PROVISIONS
4.1.
Sampling
4.2.
Acceptance Tests
4.3.
Acceptance Criteria
4.4.
General Provisions for Acceptance Tests
5.
DOCUMENTS TO BE SUBMITTED WITH THE BID
6.
MISCELLANEOUS CONDITIONS
6.1.
Bid Prices
6.2.
Special Tools
6.3.
Packing
6.4.
Documents to be Submitted for Approval
6.5.
Documents to be Submitted with the Transformers
6.6.
Inspections and Tests Outside the Acceptance Tests
6.7.
Warranty
APPENDICES
APP – I
List Of Materials
APP – II Schedule Of Guaranteed Characteristics
APP – III Drawings (2 pieces)
APP – IV Technical Specifications for Insulating Oils (2 pieces)
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TEDAŞ-MYD/95-012.C
TECHNICAL SPECIFICATION FOR
MV / LV DISTRIBUTION POWER TRANSFORMERS
(WITH OIL CONSERVATOR, EXPOSED TO AIR)
1. GENERAL
1.1. Scope
This specification covers the technical characteristics of MV/LV power transformers to be
purchased for use in medium voltage distribution networks with rated voltages up to 36 kV and
rated power from 50 kVA up to 1600 kVA.
Unless otherwise specified in this specification and its enclosures, the transformers shall be
supplied with all accessories mentioned in the specification as a complete unit filled with
insulating oil.
The types and the technical characteristics of the transformers to be purchased have been
given in the Bill of Materials and/or Schedule of Guaranteed Characteristics.
1.2. Standards
Unless otherwise specified in this specification and its enclosures, transformers shall be
manufactured and tested in accordance with the latest editions of the following Turkish
Standards (TS), European Standards (GENELEC) and International Electrotechnical
Commission (IEC) standards.
Standard No
(TSE)
TS 267
EN 60076-1
Standard No
(GENELEC, IEC
and Others)
Name of Standard
Power Transformers
IEC 60076-1
TS 10901
EN 60076-2
IEC 60076-2
TS 10902
EN 60076-3
IEC 60076-3
Power Transformers-Part3: Insulation Levels and
dielectric tests
TS 10903
IEC 60076-4
Power Tranfsormers-Part4: Tappings and Connections
IEC 60076-5
Power Transformers-Part5: Ability to Withstand Short
circuit
TS HD 428.1 S1
GENELEC HD
428.1 S1
Three-phase oil-immersed distribution transformers for
rated voltages up to 24 kV
TS HD 428.3 S1
GENELEC HD
428.3 S1
Three-phase oil-immersed distribution transformers for
rated voltages up to 36 kV
TS 8711
IEC 60551
Determination of transformer and reactor sound levels
TS 3215
IEC 60354
Loading guide for oil-immersed power transformers
TS 10904
EN 60076-5
Power Transformers-Part2: Temperature rise
TEDAŞ-MYD/95-012.C
Standard No
(TSE)
Standard No
(GENELEC, IEC
and Others)
TS EN 50180
TS EN 50386
BS EN 50386
TS HD
428.2.1. S1
TS HD
428.2.2.S1
TS HD
428.2.3.S1
TS EN 60641-1+A1
IEC 60641-1-AM1
TS EN 60641-2
IEC 60641-2
Name of Standard
Bushings-for equipment other than oil-immersed
transformers. Voltage: 1 kV – 36 kV (including) and
Current: 250 A-31.5 kA (including)
Bushings for oil-immersed transformers. Up to 1 kV and
from 250 A up to 5 kA
50 Hz, three-phase oil-immersed distribution transformers
from 50 kVA up to 2500 kVA, for equipment whose
highest voltage do not exceed 36 kV.
Part2: Distribution transformers with cable boxes on their
High Voltage and/or Low Voltage side.
Section: 1 General Characteristics
50 Hz, three-phase oil-immersed distribution transformers
from 50 kVA up to 2500 kVA, for equipment whose
highest voltage do not exceed 36 kV.
Part 2: Distribution transformers with cable boxes on their
High Voltage and/or Low Voltage side.
Section 2: Type: 1 distribution boxes used in distribution
transformers meeting the characteristics in HD.428.2.1.S1
50 Hz, three-phase oil-immersed distribution transformers
from 50 kVA up to 2500 kVA, for equipment whose
highest voltage do not exceed 36 kV.
Part 2: Distribution transformers with cable boxes on their
High Voltage and/or Low Voltage side.
Section 2: Type: 2 distribution boxes used in distribution
transformers meeting the characteristics in HD.428.2.1.S1
Characteristics for Pressboard and Pressed Paper used
for electrical purposes-Part 1: Definitions and General
Provisions.
Characteristics Required for Pressboard and Pressed
Cardboard used for electrical purposes Part 2: Test
Methods.
1.3. Service Conditions
Transformer shall be suitable for operation under following conditions:
Location use
Indoor Outdoor
Altitude
Up to 1000 m
Ambient Temperature
- Minimum .........................................
- Maximum ........................................
- Average over 24 hours....................
- 25 0C
+ 40 0C
below + 350C
Exposure to earthquakes
- Horizontal acceleration....................
- Vertical acceleration........................
0.5 g
0.4 g
The following Special Service Conditions shall be valid if specified in the Bill of Materials:
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TEDAŞ-MYD/95-012.C
Altitude *
- up to 2000 m
- up to 3000 m
Ambient Temperature **
- 400C
+ 50 0C
- Minimum .........................................
- Maximum ........................................
* :
It shall be specified by the PURCHASER in the BILL of MATERIALS
** :
For +500C ambient temperature, Winding Temperature Rise shall be 55 0K and Top Oil
Temperature Rise 50 0K.
2. CHARACTERISTICS
Power transformers, in the scope of this specification, shall be used in the distribution
networks as voltage step-down transformers or auxiliary service transformers and shall have
the following characteristics, unless otherwise specified in the Bill of Materials.
2.1. Type
-
Three phase, two windings
-
Oil-immersed (mineral oil), with oil conservator, exposed to air
-
Natural oil circulation and natural air cooling (ONAN)
-
Off-Load tap adjustment for voltage settings
-
Suitable for Outdoor or Indoor uses
2.2. Electrical Characteristics
2.2.1. Rated Frequency
: 50 Hz
2.2.2. Rated Powers
: 50-100-160-250-400-630-800-1000-1250-1600 kVA
2.2.3. Highest System Voltages (primary) : 7,2-12-17,5-36 kV
(Secondary) : 1,1 kV
2.2.4. Rated Voltages
• HV Winding (Main tapping)
: 6.3-10.5-15.8-33 kV
• LV Winding
: 400/231 V
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2.2.5. Off-Load Voltage Adjustment
• Tapping Winding
: On the HV side
• Voltage adjustment range
: Constant flux (TS-SAA; IEC-CFVV)
• Tapping (adjustment) class
6.3-10.5-15.8 kV
33 kV
• Tapping (adjustment) class
: ± 2 x 2.5 %
28.5-30-31.5-33-34.5 kV
• Number of taps
:
• Off-Load tap ratio
: HV±2x2,5%/0.4 kV 28.5-30-31.5-33-34.5/0.4 kV
5
5
NOTE: Values written in bold letters are the main taps.
2.2.6. Tapping Powers
• 6.3-10.5-15.8 kV transformers
: Equal to the rated power for all taps
• 33 kV transformers
: Equal to the rated power between 30 kV and
34.5 kV
2.2.7. Temperature Rise
• For windings
: 65 K
• For highest oil level
: 60 K
2.2.8. Connection Symbol
Up to 160 kVA (including 160 kVA)
Yzn 11
250 kVA and up
Dyn 11
2.2.9. Impedance Voltages (at 75 0C, and main tap)
Impedance Voltage
Uk (%)
Transformer power (kVA)
6.3-10.5-15.8 kV
33 kV
Up to 630 kVA (including 630 kVA)
4
4.5
Above 630 kVA
6
6
2.2.10. Short Circuit Thermal Withstand
Transformer Power (kVA)
Short Circuit Duration
Up to 630 kVA (including 630 kVA)
2 seconds
Above 630 kVA
3 second
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2.2.11. Rated Insulation Levels
HV winding:
Rated voltage
Impulse withstand voltage
(kV-peak)
(1.2 - 50µs)
One-minute power-frequency
withstand voltage
(kV-rms)
6.3 kV
60
10.5 kV
75
15.8 kV
95
33 kV
170
20
28
38
70
LV winding:
One-minute power-frequency withstand voltage (kV-rms) ………………: 3 kV
2.2.12. Sound Power Levels (LWA)
Transformer power (kVA)
50
100
160
250
400
630
800
100
125
160
0
0
0
6.3-10.5-15.8 kV
55
59
62
65
68
70
72
73
74
76
33 kV
52
56
59
62
65
67
68
68
69
71
NOTE: The values in the Table are the highest values. Tolerance shall not be applied.
2.2.13. Losses
Rate voltage
(kV)
Up to 15.8 kV
33 kV
Rated Power
(kVA)
50
100
160
250
400
630
800
1000
1250
1600
50
100
160
250
400
630
800
1000
1250
1600
No-Load Losses
Pb (W)
190
320
460
650
930
1300
1500
1700
2100
2600
230
380
520
780
1120
1450
1750
2000
2250
2800
Load Losses
Py (W)
1100
1750
2350
3250
4600
6500
8500
10500
13000
17000
1250
1950
2550
3500
4900
6650
8700
10500
13000
17000
NOTE: The values in the Table are the highest values. Tolerance shall not be applied.
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TEDAŞ-MYD/95-012.C
2.2.14. Operation (Loading) Mode
Transformers shall be suitable for continuous operation under 100 % unbalanced loading.
2.2.15. Operation Under Overvoltage Conditions
Transformers shall be suitable for continuous operation under the following overvoltage
conditions;
• At 105% of rated voltage and at rated current
• At 110% of rated voltage at no-load
Note: The slight temperature rise increase which would correspond to the 5% overvoltage, due
to higher no-load loss, is disregarded.
2.2.16. Temporary Overloading
Shall be in accordance with TS 3215/IEC 60354 standards.
2.2.17. Tolerances
Each transformer in the scope of the order, shall be considered as complying with this
specification when the guaranteed characteristics are found within the following tolerances.
Voltage ratios at no-load
(at the main tap)
: ± 0.5%
Impedance voltage
(At rated current)
: ± 10%
No-load current
: + 30%
Losses
: + 0%
2.3. Constructional Characteristics
2.3.1. Magnetic Circuit
The core shall be manufactured of high-grade silicone-steel laminations with low losses.
2.3.2. Windings
Windings and winding connections shall be designed and manufactured in a way that they
shall withstand thermal and dynamic stresses due to short circuits at transformer terminals,
and insulation withstand tests, specified in the specification without any damage. Windings
shall be dried out under vacuum.
2.3.3. Insulation
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TEDAŞ-MYD/95-012.C
1
For insulation of the windings, high grade insulation materials of at least Class-A material shall
be used. Neutral ends and line ends of the same LV windings shall have the same insulation
level.
2.3.4. Oil Filling
The oil-filling of transformers shall be made under vacuum.
2.3.5. Tap-Changer
Each transformer shall be supplied with off-load tap-changers mounted at the HV winding.
The construction of regulation windings and tap-changers shall be strong enough to withstand
against high voltage impulses, overload and short-circuit currents without any damage.
Tap-changing operation shall be performed by means of a control mechanism mounted on the
top cover of the tank. Control mechanism shall be marked such that the tap position 1 shall
indicate the minimum number of turns of the windings. For each of the tap positions tap
indicator shall have a stop slot.
2.3.6. Tank and Cover
Tank and cover shall be fabricated of high grade steel plates with high durability and best
workmanship. Tank base shall have a chassis which will carry all the weight of the transformer
on four wheels.
All the bolts and nuts on the tank shall be made of stainless or galvanized steel.
Welding shall be carried out in accordance with strict standards, with double weld provided
where tightness is required. All oil-tight welds shall be tested to ensure that no oil leakage will
occur.
All the gaskets for leakage prevention shall be manufactured by using materials resistant to
insulating oil and suitable for use within operation temperature range of the transformer, and
shall not deteriorate the characteristics of the insulating oil2
Metal continuity shall be ensured between the parts forming the tank and the various pipes etc.
so that they will all be at the same potential.
The tank shall be equipped with the following arrangements and equipment:
-
Two lifting rings, to lift the transformer safely and to pull out the core and windings together
with the cover from the tank,
1
The highest permissable temperature for the insulating material Class A is 105 C (FOR INFORMATION)
o
2
Sample gasket material: Neopren, Nitrile. (All responsibility in the choice of gasket, shall belong to Manufacturing firm)
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TEDAŞ-MYD/95-012.C
-
Four wheels, which are lockable and orientable in two perpendicular directions (the
transformers having the rated power 250 kVA or less, shall be designed for wheel
mounting, but the wheels shall not be delivered for these transformers).
-
An oil sampling and oil drain valve located at 2-3 cm above the tank base (in conformity
with DIN 42551, at the same level as the winding base, sealed),
-
Thermometer pocket (for transformers having rated power 400 kVA or less and in
conformity with DIN 42554),
-
Two earthing terminals (in conformity with DIN 48088-B)
Two M12 size bolted type, earthing terminals from stainless steel shall be provided, one of
which shall be on the cover and the other on the side surface, at the base. The bolts, shall
be equipped with nut, washer and spring-washers, made also from stainless steel.
Earthing terminals shall be marked with earth symbols.
2.3.7. Cooling Equipment
Sheet thickness of the fixed flat or corrugated-wall type radiators to be used in the natural
cooling of the transformers, shall not be less than 1.2 mm.
2.3.8. Oil-Conservator
Each transformer shall be equipped with an oil-conservator of suitable capacity and the oilconservator shall include following arrangements:
-
Oil precipitation arrangement
Oil drain tap
Oil filling tap (according to DIN 42533)
Magnetic oil level indicator (according to DIN 42569)
Connection flange for air dryer (for 250 kVA and larger units)
For 630 kVA and larger units, an arrangement for mounting of Buchholz relay on the pipe
connecting the conservator to the tank.
2.3.9. Bushings and Terminals
The HV line & LV windings and LV neutral ends shall be taken out through ceramic bushings,
having the same insulation level with the relevant windings.
2.3.9.1 HV Bushings and Terminals
• HV bushings and terminals shall comply with TS EN 50180 standard, be Open Type or
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TEDAŞ-MYD/95-012.C
Outside Cone-Plug-in Type as indicated in the Bill of Materials. In case any specific type is
not specified in the Bill of Materials, Open Type Bushings shall be used.
• Bushings’ rated current shall be 250 A.
• Insulating material of Open Type HV Bushings shall be ceramic and insulating material of
Plug-in Type HV Bushings shall be epoxy resin.
• Minimum Rated Specific Creepage Distance for Open Type HV Bushings shall be chosen
by the PURCHASER according to the following Table and specified in the Bill of Materials.
Pollution Level of
the Medium
(According to IEC 60815)
Surface I (Slightly polluted)
Rated
Distance
Specific
Creepage
16 mm / kV
Surface II (Moderately polluted)
20 mm / kV
Surface III (Heavily polluted)
25 mm / kV
In case any alternative is not indicated in the Bill of Materials, Rated Specific Creepage
Distance shall be selected as 20 mm/kV.
NOTE: Outside Cone-Plug-in Bushings shall be used with detachable full-insulated cable
terminals (sealing ends). Unless otherwise specified in the Bill of Materials, Detachable Cable
Sealing Ends shall be supplied by the PURCHASER.
2.3.9.2 LV Bushings and Terminals
LV Bushings and Terminals shall comply with TS EN 50386 standards, shall be open type and
shall have ceramic insulating material. The number, rated current and rated voltage of the
bushings to be used according to the powers of the distribution transformers, are given below:
Transformer Rated
Power kVA
Bushings
Rated Current
(Amper)
250
Number
Rated Voltage
(kV)
1
50 – 100 – 160
4
250 – 400
4
630
1
630 – 800
4
1250
1
1000 – 1250
4
2000
1
1600
4
3150
1
NOTE: Connectors to be used for connection of cables or flat busbar conductors to the LV
terminals shall be supplied with 630 kVA or larger transformers.
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TEDAŞ-MYD/95-012.C
2.3.10. Cable Box
In case it is specified in the Bill of Materials, in order to prevent an accidental touch to the parts
under voltage, a metallic and/or non-metallic protective enclosure (Cable Box) shall be
provided in the HV or LV connection end arrangements of the transformer.
Construction of Protective Enclosure (Cable Box) shall comply with TS HD 428.2.3.S1.
NOTE: In case Plug-in Type, Outside Cone Type bushings are used on the HV side of indoor
type distribution transformers, no Cable Box shall be required on their HV side.
2.3.11. Protection and Signalling Equipment
Following protection and signaling equipment for transformers shall be supplied unless
otherwise specified in the Bill of Materials:
-
Air dryer, (For units with 250 kVA and higher capacity, in compliance with DIN 42567),
-
Buchholz relay, (two-stage), (For units with 630 kVA and higher capacity, in compliance
with DIN 42566),
-
Double-scaled, double-contact bimetal thermometer (For units having 630 kVA and higher
capacity, in compliance with DIN 16160),
-
Clemens box (for units with 630 kVA and higher capacity. Enclosure of the clemens box
may be of a metallic or insulating material and have a Protection Level of at least IP 44.
Should it be of insulating material, the material to be used shall be flame-resistant).
2.3.12. Insulating Oil
Transformers shall be delivered with their oil filled-in. Oil used for filling transformers shall be
new and free of humidity and with a characteristics which will not cause precipitation. Unless
otherwise specified in the Bill of Materials or Bidding Documents, the insulating oil shall comply
with the enclosed Transformer Oil Specifications. Should the PURCHASER deems necessary,
may cause the oil sample he will take from a manufactured transformer outside the
Acceptance Tests, according to the relevant oil specifications. The results of the test shall be
binding for the CONTRACTOR.
The type and brand of insulating oil used shall be indicated in the routine test reports and as
well as on the nameplates of all the transformers within the scope of the order.
2.3.13. Arrangement of the Top Cover and Dimensions
Arrangement of HV and LV bushings on the top cover, marking of the connection terminals,
location of the oil conservator as well as distances between wheels’ axis shall be according to
the drawings given in APP.III.
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TEDAŞ-MYD/95-012.C
Marking of low voltage, high voltage and external neutral terminals of the transformer shall be
carried out on the tank cover.
Marking shall be durable (for instance: marking by punch, etc.), easily visible and legible.
Painting, label-sticking or similar marking procedures shall not be accepted. Marking shall be
carried out as follows:
MARKING ON THE COVER
High Voltage
Low Voltage
For connection conductor L1
1U
2U
For connection conductor L2
1V
2V
For connection conductor L3
1W
2W
-
2N
For neutral connection conductor
2.3.14. Dimensions
The maximum external dimensions of transformers including the oil conservator and the
wheels shall not be greater than those given in the table below.
Dimensions (Maximum) of MV/LV Power Transformers
Up to
630
800-1000
1250
1600
400 kVA
kVA
kVA
kVA
kVA
Width (mm)
1100
1200
1300
1500
1850
Length (mm)
1700
1700
2100
2100
2100
Height (mm)
1950
1950
2250
2300
2450
NOTE: Cable Box is not included in the dimensions
2.3.15. Nameplate
Each transformer shall have an easily visible nameplate made of stainless steel or other noncorroding metal. The nameplate shall be fixed on the transformer with stainless steel screws or
rivets and the lettering shall be legible and durable.
In addition to the information given in TS 267/EN 60076-1, following information shall be
included on the nameplate.
-
Purchaser’s name and order number
Year and month of manufacture
Type and brand of insulating oil
No-load losses and load losses
Numbers of tapping positions and the
corresponding voltages (V and/or kV)
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TEDAŞ-MYD/95-012.C
-
Insulation measurement results
Purchaser’s material code number
Each transformer shall bear the Purchase’s symbol and/or name with letters of 25 mm height
on two opposite sides of the transformer or on the oil conservator.
2.3.16. Anticorrosion Precautions
2.3.16.1 General
Metal parts of the transformers shall be manufactured with corrosion resistant materials and be
finished in such a way that corrosion is minimized.
The following precautions shall be taken against corrosion:
Current-carrying parts shall be made from non-ferrous metals
All surfaces shall be self-draining
Materials and combination of materials used in the construction of the equipment shall be
selected and arranged in a way to prevent galvanic corrosion;
Aluminium alloys used for current carrying or structural purposes, shall be resistant to
corrosion,
Ferrous parts shall be either hot-dip galvanized or painted,
Surfaces to be galvanized or painted shall be sound, clean and free from any foreign
materials which will in any way reduce the life and functioning of the coating.
2.3.16.2 Painting
All the externally exposed surfaces such as tank, radiator, oil-conservator etc. and all parts of
the transformers manufactured by using corroding metals, unless otherwise specified in the Bill
of Materials, shall be painted.
In case the internal surfaces of the tank are painted or coated with varnish, the paint or varnish
to be used shall have rust-inhibiting characteristics and shall not be affected from the
maximum temperature (at least 105 0C) reachable by the insulating oil.
For the painting of exterior surfaces following procedure shall be adopted:
Prior to painting, all surfaces shall be subjected to complete cleaning process according to
methods given in painting standards (such as sandblasting or chemical cleaning, etc.)
Coating with zinc by hot dipping.(If requested at the Bill of Materials)
Catalyzed epoxy paints with anti-corrosion pigments shall be used for primary-coating.(In
case of a request by coating with zinc, the
primer paint shall be chosen by the firm.)
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TEDAŞ-MYD/95-012.C
Any paint, for intermediate coats, may be selected by the Manufacturer.
One of the following types of paints having color code RAL 7033;
-
Polyurethane paints;
-
Alkyd and silicone-based paints;
-
Modified vinyl paints;
shall be used as finishing coat.
The minimum thickness of each coat shall be 35 microns. Painting of the transformers shall be
completed before the routine tests. The thickness of the film at five points, chosen at random
on the painted surface, shall be measured by employing a paint inspection gauge. The mean
of the values measured shall not be less than 105 microns.
The quality of painting shall be determined by checking the thickness and adhesion of
coating.
The film adhesion shall be verified by the adhesive tape test according to TS 4313/ASTM D
3359. The degree of adhesion shall not be worse than Class-1 mentioned in these standards.
2.3.16.3 Galvanizing
Galvanizing and tests on galvanized surfaces shall be carried out in accordance with TS 914
“Galvanizing (with the hot-dip method)”.
3. TESTS
Unless otherwise specified, the tests shall be carried out according to relevant standards, on
completely assembled and oil filled transformers.
3.1. Type Tests
Full wave impulse test,
Temperature rise (heating) test,
The test shall be performed for 33/0.4 kV transformers at the 30 kV tapping; and for 6.310.5-15.8/0.4 kV transformers at the lowest tapping, with the corresponding load losses
taken into account.
Measurement of sound power level,
Dynamic ability to withstand short-circuit test (DAWSCT), Unless any design difference
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TEDAŞ-MYD/95-012.C
exists, distribution transformers are grouped with respect to DAWSCT as follows:
Rated Voltage (kV)
6.3-10.5-15.8
33
50 – 160
50 – 160
250 – 630
250 – 630
800 – 2500
800 - 2500
Transformer Rated
Power (kVA)
Checking of quality of painting (According to Clause 2.3.16.2 of this specification)
3.2. Routine Tests
Following routine tests shall be carried out by the Manufacturer on all of the fully manufactured
transformers in the scope of this specification:
Measurement of winding resistance,
Measurement of voltage (turn) ratio and check of voltage group symbol,
Measurement of impedance voltage (short circuit impedance) and load losses,
Measurement of no-load loss and current,
Applied voltage test,
Induced voltage test,
Measurement of insulation resistance,
The measurement shall be carried out between windings and between each winding and
tank at 0,15,30,45 and 60 seconds, by 2500 V or 5000 V insulation tester on oil filled
transformers and the results shall be corrected to 20 0C. The measurement results at 60
seconds shall be indicated on the nameplate of the transformer.
Measurement of loss angle tangent
For transformers with rated power of 630 kVA or higher, the loss angle tangent or power
factor (tan δ or Cos∅) between windings and between each winding and the tank shall be
measured by a Schering bridge or Doble instrument and the results shall be corrected to
20 0C.
Oil Leakage Tightness Test, (to test oil leakage and oil tightness)
Measurement of paint thickness (According to Clause 2.3.16.2 of this specification)
14
TEDAŞ-MYD/95-012.C
4. ACCEPTANCE TESTS AND PROVISIONS
4.1. Sampling
The transformers which are submitted for inspection and testing at one time and having the
same design and type, shall be considered a party.
The samples shall be selected at random by the PURCHASER’s representative /
representatives. The number of samples shall, unless otherwise specified, be determined
according to the following table.
Party Size
1 – 10
11 – 30
31 – 50
51 – 100
101 – 200
Sample Size
2
3
4
6
8
4.2. Acceptance Tests
The type test specified in the Contract:
Shall be performed on an appropriate number of samples, depending upon special
requirements of the test.
The routine tests specified in Clause 3.2: (Oil tightness test shall be performed as specified
below.)
Oil-tightness Test:
Shall be performed on every selected sample. The test shall be performed by applying
inside the tank a pressure which is equal to two times the static oil pressure to be measured
at the base of the tank. Duration of the test shall be 12 hours. No oil leakage shall occur in
the transformer at the end of the test.
Insulating Oil Tests:
Unless otherwise specified in the Bidding Documents, shall be performed on a sample to be
taken from supplied ones. Breakdown voltage, Water Content, Interior Surface Tension,
Neutralization Number and Power Factor (at 250C and 100
0
C) shall be measured
(According to the relevant oil specification).
Oil sample, shall be taken two times in the presence of the Supplier/Manufacturer’s
representative(s) in Oil Sampling Jars, one of them as witness sample, and the lids of the
jars shall be properly sealed by the PURCHASER. Oil Sampling Jars shall be provided by
the Manufacturer/Supplier. Of the two samples, one shall be sent to the test, while the other
will remain at the manufacturing firm as a witness sample. All responsibility for the process
of proper sampling shall lie with the manufacturing firm.
4.3. Acceptance Criteria
15
TEDAŞ-MYD/95-012.C
i.
All type tests shall have positive result.
In case of a negative result that causes the PURCHASER to reach the conclusion that
service reliability of the transformers will be lost, it may reject all the transformers in the
party. The Purchaser, at its unobjectionable judgement, may accept the repetition of the
test, if the Supplier proposes to modify within a reasonable period of time the design of
the transformers and to repeat at its own expense, all the type tests specified in the
Specification.
ii.
All Routine Tests and Oil Tightness Test shall produce positive results. Should the
results of any routine tests on any sample prove negative, then these test(s) shall be
repeated on all the transformers in the party.
In this case, the defective units shall be replaced or repaired at the full expense of the
Supplier.
iii.
In case a negative result is obtained from the Insulating Oil Sample sent for test, witness
sample shall be tested. In case a positive result is obtained from the witness sample, the
result of the test shall be accepted as POSITIVE. Otherwise, it will be concluded that the
insulating oil of the transformers comprising the delivery lot in question is inappropriate
and request will be made for the insulating oil of the transformers in the scope of the
delivery to be improved to acceptable conditions. The Supplier shall not be given any
extention of time for these operations.
4.4. General Provisions for Acceptance Tests
i.
Upon the signing of the Contract, the Supplier shall notify the Purchaser of a Test
Program, at least 20 (twenty) days in advance for the tests to be performed abroad and
at least 7 (seven) days in advance for the tests to be performed in Turkey, which shall
cover the information such as name, place and starting date of tests.
ii.
Acceptance tests shall be carried out under the supervision of the PURCHASER’s
representative(s). Unless otherwise specified in the Contract, performance of acceptance
tests on the Manufacturer’s premises is essential. Tests which are included in the scope
of acceptance tests but can not be performed on the manufacturer’s premises, may be
carried out in another place to be deemed appropriate by the PURCHASER,
Implementation regarding type tests shall be made according to Clause 4.4.iii herein.
iii.
Type tests to be performed within acceptance tests, may be carried out at an accredited
laboratory or alternatively, at an unaccredited laboratory but under the supervision of the
PURCHASER’s representative(s). Other acceptance tests shall not start before the
submission to the PURCHASER of the type test reports with positive results. In case the
type tests are performed at an accredited laboratory, the presence of the PURCHASER’s
representative(s) is not necessary.
iv.
The Purchaser, by notifying the Supplier in due course, may inform that it will not attend
the tests. In such a case the Supplier shall carry out the tests together with the
Manufacturer
and
notify
the
PURCHASER of their results. The test reports
16
TEDAŞ-MYD/95-012.C
prepared and signed together by the Supplier and Manufacturer, shall be sent to the
PURCHASER in 2 (two) copies for review and approval. If test reports are approved, the
PURCHASER shall issue a Release Note for shipment and return 1 (one) approved set
of the Test Reports to the Supplier.
v.
Outside the reasons arising from the PURCHASER’s actions (failure to be present at the
test site on the date notified, failure to reach a clear decision on the test results etc.), no
extention of time shall be given to the Supplier for delays that may occur in the delivery
due to incompletion of acceptance tests.
vi.
No payment shall be made to the Supplier before the conclusion of acceptance tests.
vii.
Test reports shall include the serial number(s) and characteristics of the sample(s)
tested. Test reports shall also clearly state the compliance or incompliance of the test
results with this specification and than shall be countersigned. In case the test results
and other related issues (if any) stipulated in the specification are appropriate, the
PURCHASER’s representative(s) shall give permission for the shipment of relevant party
of goods.
The Purchaser’s representatives may leave the decision to the General Management, if
a clear decision concerning the test results can not be reached by them.
5. DOCUMENTS TO BE SUBMITTED WITH THE BID
Schedule of Guaranteed Characteristics
Schedule of Guaranteed Characteristics shall be signed by the Bidder and the Manufacturer
firm after being filled in separately for the transformer in each item. Information given in
these schedules shall be binding for both the Bidder and the Manufacturer firm.
Type test reports and certificates
Bidders are required to submit with their bids, reports or certificates of type tests carried out
in an accredited laboratory.
Reports of type tests which were carried out with the presence of PURCHASER’s or TSE’s
representatives, may also be accepted. The test reports must belong to the type of
equipment offered. Therefore, the PURCHASER, if deems necessary, may ask the Bidder
the proof that the test reports belong to the type of equipment offered.
The test reports shall contain the name of the laboratory, names, titles, and signatures of
observers and persons performing the tests, and the date of tests.
If the equipment offered are manufactured under a license, type test reports shall belong to
the transformer produced in the place where the manufacturing process in question is being
carried out.
The Purchaser reserves the right to determine to its satisfaction to evaluate the bids of the
Bidders who did not submit appropriate or any type test reports, provided that the type tests
to be carried out in Turkey shall be carried
17
out on a sample unit to be selected out of the
TEDAŞ-MYD/95-012.C
first delivery lot, and the type tests to be carried out abroad shall be carried out before the
first lot is delivered, at the Supplier’s cost.
Following documents and drawings;
In addition to the Schedule of Guaranteed Characteristics, the Bidders shall submit their
bids with following documents for each type of equipment offered.
-
T.S.E. Certificate,
-
ISO 9000 : 2000 Quality System Certificate and ISO 14 000 Environment Management
Systems Certificate, held by the Manufacturing firm,
-
Detailed catalogues, manuals for mounting, operation and maintenance instructions,
-
Descriptive information and drawings concerning tank, type of core and windings and
winding arrangement,
-
Drawings with overall dimensions and location of auxiliary equipment,
-
Drawings with transport dimensions and transport weights.
The Bidder’s failure to submit any of the documents required herein or any missing data may
entitle the PURCHASER to reject the bid.
6. MISCELLANEOUS CONDITIONS
6.1. Bid Prices
The bid units prices shall be given in accordance with the relevant terms of the bidding
documents:
The bid unit prices shall include the prices of:
-
The complete transformer with all the equipment required in the specification,
Acceptance tests,
Special tools (if any)
Packing
6.2. Special Tools
If special tools are required for mounting and dismantling of transformers, these special tools
shall be delivered together with transformers and list of the tools shall be specified in the bid,
18
TEDAŞ-MYD/95-012.C
6.3. Packing
Transformers shall be delivered together with their bushings, radiators oil-conservators and all
other specified accessories and equipment (except wheels) mounted on them and their oil
filled in. Transformers shall be delivered without packing, but necessary measures shall be
taken to protect the bushings from breakage during transportation and storage by enclosing
them into wooden boxes fixed to the tank properly.
Parts which shall be delivered as unmounted on the transformer, such as spare parts, special
tools, wheels (if any) shall be placed into a separate wooden box and delivered together with
the transformers. Packing box shall be marked with transformer brand, characteristics and
order number.
6.4. Documents to be Submitted for Approval
After the signing of the Contract, the Supplier shall submit the following drawings in 2 (two)
copies for approval within an appropriate time, taking into account the delivery program,
Drawings indicating the overall dimensions of transformers complete with all auxiliary
equipment,
Nameplate drawings
Warning labels
The approval of drawings and documents shall not relieve the Supplier of his obligations for
carrying out the terms of the Contract, and of his responsibility for correctness of drawings and
manufacturing according to technical aspects.
The drawings submitted for approval shall be approved and sent back to the Supplier not later
than 10 (ten) days, however any delay due to late submission of drawings shall not entitle the
Supplier to claim for a time extension.
6.5. Documents to be Submitted with the Transformers
Following documents shall be submitted with each transformer, enclosed in a plastic protection
envelope
Operation and maintenance instruction
Approved drawings
Routine test reports
Type, brand and weight of insulating oil.
Warranty Certificate obtained from the Manufacturer
6.6. Inspections and Tests Outside the
Acceptance Tests
19
TEDAŞ-MYD/95-012.C
i.
The fact that goods have been inspected, tested and accepted by the PURCHASER’s
representative(s) before loading, shall not restrict or remove the right of the PURCHASER
to re-inspect, re-test and, if necessary, reject them at their last point of delivery.
ii.
The PURCHASER may, at its unobjectionable judgement, decide upon the repetition of all
or a part of type tests or routine tests on the manufacturer’s premises or at an accredited
laboratory either inside or outside the country, within the contract period.
Sample(s) shall be selected by the PURCHASER’s representative(s) and countersealed.
Should the result of the tests to be performed prove positive, all the costs thereof shall be
paid by the PURCHASER. However, If the result of the tests come out negative all the test
expenses shall be borne by the Supplier. The PURCHASER may, at its unobjectionable
decision, decide on the change of such transformer with the appropriate ones, after the
performance of the relevant type tests and routine test of the latter, provided that this
change shall be done within a reasonable period of time and that all the expenses shall
met by the Supplier, or it may decide on the unilateral cancellation of the contract.
6.7. Warranty
The Supplier shall warrant that each transformer of the supply shall have no defects arising
from design, materials or workmanship, for a period of 24 months after the date of delivery.
Should the transformers become defected/damaged within the warranty period, defected
transformers shall be transported to the manufacturer by the PURCHASER for expertise. At
the end of this expertise:
i.
In case it is determined that the transformer has become defected/damaged due to
reasons arising from the Manufacturer such as design, workmanship, material and/or
packing (including the reason that some other construction is used than the one used
during the type tests), it shall be repaired or replaced by a new unit at full expense of the
Manufacturer/Supplier and transported to the destination to be indicated by the
PURCHASER. The expenses incurred by the PURCASER during the transportation of the
transformers to the Manufacturer, shall be repaid by the Manufacturer to the
PURCHASER.
ii.
In case it is determined that the same quality of material as stipulated in the specification
is not used, notwithstanding the determination that the transformer has become defected
due to reasons arising from operation, the reason of this defect shall be attributed to the
Manufacturer and the case shall be treated within the scope of clause “i”.
iii.
In case it is determined that the transformer has become defected due to reasons arising
from operation and if its repair is decided by the PURCHASER, the necessary repair work
shall be carried out on the Manufacturer’s premises at the contract unit price3 which were
3
In determining repair cost ,the unit prices to be used are determined according to following clarifications:
20
TEDAŞ-MYD/95-012.C
realized at the latest transformer repair contract awarded by the General Management
within the last two years (excluding transformers with wound type cores), and the
calculated sum shall be paid by the PURCHASER. If no repair work has been carried out
within the last two years, repair price shall be determined by mutual negotiations.
iv. In case no determination can be made as to which party is responsible for the
transformer’s defect:
-
The transformers which are decided to be repaired, shall be repaired on their
manufacturer’s premises, and repair price, to be determined according to the clause
“iii”, shall be shared on a fifty-fifty basis between the PURCHASER and the
Manufacturer.
-
In case the transformer is replaced with a new unit, the price included in the relevant
purchasing contract shall be met on a fifty-fifty basis by the PURCHASER and the
Manufacturer.
-
The transformer repaired or replaced with a new unit, shall be transported by the
Manufacturer to the destination indicated by the PURCHASER at expense of the
Manufacturer.
The Manufacturer, shall get the defective/newly replaced transformer ready for acceptance
within at the latest 1 (one) month as of the date of expertise. Upon the completetion of
acceptance tests, the transformers repaired within the scope of “I”, “ii” and “iv”, shall be
transported to the destination to be indicated by the PURCHASER within 15 (fifteen) days at
the latest. If the Manufacturer fails to meet the repair and transportation expenses arising from
his own default, these expenses and costs shall be collected from the earnings or performance
security of the Supplier.
The repaired or replaced equipment shall be covered by the same warranty stipulations.
- Should the repair contract has been awarded on a fixed price basis and the main order still continues, exactly same prices of the
relevant contract are used.
- Should the repair contract has been awarded on a fixed price basis and main order already completed; contract prices are escalated,
taking into account the date of completion of the main order according to the delivery program and using DEI’s Wholesale Price
Index.
- Should the repair contract has been awarded on a escalated price basis, contract prices are escalated to the date of expertise
according to the escalation formula and the prices thus found are used.
21
TEDAŞ-MYD/95-012.C
APPENDICES
APP. – I
BILL OF MATERIALS
APP. – II
SCHEDULE OF GUARANTEED CHARACTERISTICS
APP.– III
DRAWINGS
APP.– IV
TECHNICAL SPECIFICATION FOR INSULATING OIL (TWO COPIES)
22
TEDAŞ-MYD/95-012.C
APP. – I
BILL OF MATERIALS FOR
MV/LV DISTRIBUTION POWER TRANSFORMERS
File No:
1
Rated Power
2
Rated Voltage
3
UNIT
kVA
- HV winding
kV
- LV winding
kV
1
ITEM NO
2
3
Service Conditions
- Altitude
meter
- Lowest ambient temperature
0
- Highest ambient temperature
0
C
C
- Environment Pollution
4
Off-load voltage regulation
- Voltage regulation range
- Number of taps
5
Connection symbol
6
HV Bushing
-(Open type/Outside Cone Type)
7
Cable Box
- at HV-(YES/NO)
- at LV-(YES/NO)
8
Other Issues
(Other issues requested by the PURCHASER as different from the technical specification shall be
written in this part.)
9
PURCHASER’s material code number
-
10
Quantity to be purchased
PIECES
23
TEDAŞ-MYD/95-012.C
APP. – II
SCHEDULE OF GUARANTEED LIST
File No
: ………………
Item No
: ………………
Purchaser’s Material Code No. : ………………
UNIT
1
Manufacturer’s name
-
2
Manufacturer’s type designation
-
3
Numbers of Standards applied
4
Type
-
5
Rated power
kVA
6
Rated voltage
- HV winding
GUARANTEED
with conservator exposed to the air
-
- LV winding
-
7
Voltage regulation range and number of taps
-
8
Voltage regulation type
-
9
Connection symbol
10
Service Conditions
HV and Off-load
- Service altitude
meter
- Lowest ambient temperature
0
C
- Highest ambient temperature
0
C
- Environment Pollution
-
11
HV Bushing
(Open type/Outside Cone Plug type)
-
12
Rated creepage distance for Open type HV
Bushings
13
Cable Box
kV/mm
- at LV (YES/NO)
- at MV (YES/NO)
14
15
16
Temperature Rise Limits
- LV Winding
K
*
- HV Winding
K
*
Top oil
K
*
- One-minute power frequency withstand voltage
for HV windings
kV-rms
*
- One-minute power frequency withstand voltage
for LV windings
kV-rms
*
- Lightning Impulse withstand voltage for HV
windings (1.2-50 microsecond)
kV-rms
*
Insulation Levels
Impedance Voltage (at 750C)
- at main tapping
%
- at highest tapping
%
- at lowest tapping
%
24
TEDAŞ-MYD/95-012.C
UNIT
GUARANTEED
*
17
No-load losses (at main tapping voltage)
Watt
18
No-load current (at main tapping voltage)
%
19
Load Loss (corrected to 75 C)
o
- At main tapping
Watt
- At highest tapping
Watt
- At lowest tapping
Watt
20
Sound power level
LWA
21
Thermal ability to withstand short-circuit
Sec.
22
LV Winding
*
- Conductor material (aluminum/copper)
23
- Conductor cross section
mm 2
- Conductor type (metal foil-rectangular)
-
- Coil type
-
Circular concentric
Non-circular concentric
HV Winding
- Conductor material (aluminum/copper)
24
- Conductor cross section
mm 2
- Conductor type (metal foil-rectangular)
-
- Coil type
-
Circular concentric
Non-circular concentric
Conductor weight of windings
- LV winding
Kg/phase
- HV winding
Kg/phase
25
Core type (shell type/core type)
-
26
Quality of silicone steel laminations used
-
27
Magnetizing flux density
Wb/m 2
28
Weight of magnetic circuit (core)
Kg
29
Weight of tank
Kg
30
Insulating oil brand and type
-
31
Weight of oil
Kg
32
Weight of complete transformer
Kg
33
Gasket used between Tank and Cover;
- Gasket material
- Gasket type (cork, round etc.)
34
Dimension (without Cable Box)
- Width
- Height
- Length
- Height of Upper Cover
25
**
TEDAŞ-MYD/95-012.C
UNIT
35
GUARANTEED
Dimensions (with Cable Box)
- Width
- Height
- Length
- Upper cover height
(*): This part shall be filled in, if the guaranteed values are different than those specified in the
Technical Specification.
(**) : As mineral-based oils, oils with brand such as NYNAS-NYTRO 10 GB XT, SHELL-DIALA
AX, TECHNOL-296 XT, NYNAS-NYTRO 10 XT; TECHNOL-2000 shall be used in
transformers. In case a mineral-based different oil is proposed, the sample of the oil proposed,
shall be tested in TEİAŞ’s Chemical Laboratory according to the relevant oil specifications
given in the appendix. All the test expenses (regardless of the test results) shall be borne by
the Supplier. In case positive results are obtained from the tests, use of the oil in question shall
be permitted.
26
TEDAŞ-MYD/95-012.C
APP-III/1
PRINCIPLE DRAWINGS SHOWING
INSULATORS, OIL CONVERSATOR LOCATION, MARKING OF CONNECTION TERMINALS
AND DISTANCES BETWEEN WHEELS FOR DISTRIBUTION
POWER TRANSFORMERS WITH CAPACITIES 160 kV AND BLOW
“IMPORTANT: The Drawings at the Turkish Copy of this
specification, shall be taken as the Basis for all Bidding.”
FRONT VIEW
VIEW-A
50-160 kVA
1
2
3
4
5
D
G
VIEW FROM TOP
27
D
520 mm
G
50 mm
Name plate
Lifting ring
Earthing Terminal
Oil Drain Valve
Tap Changer
Distance Between Wheels
Width of Wheel
TEDAŞ-MYD/95-012.C
APP-III/2
PRINCIPLE DRAWINGS SHOWING INSULATORS, OIL CONVERSATOR LOCATION,
MARKING OF CONNECTION TERMINALS, DISTANCES BETWEEN WHEELS FOR DISTRIBUTION
POWER TRANSFORMERS WITH CAPACITIES 250 kVA AND UP
“IMPORTANT: The Drawings at the Turkish Copy of this
specification, shall be taken as the Basis for all Bidding.”
FRONT VIEW
VIEW-A
250 kVA
400-630 kVA
800-1600 kVA
1
2
3
4
5
6
D
G
D
520 mm
670 mm
820 mm
G
50 mm
50 mm
70 mm
Terminal Box
Name Plate
Lifting Ring
Earthing Terminal
Tap Changer
Oil Drain Valve
Distances Between Wheels
Wheel Width
VIEW FROM TOP
NOTES:
Protective equipment specified in the technical specification depending on the transformer power, are shown on the drawings.
Placement of the protective equipment included in the technical specification shall be carried out by the manufacturing firm.
28