TECHNICAL SPECIFICATION OF 48 VOLTS 300/120AH SMPS BASED BATTERY
CHARGER SUITABLE FOR VRLA MAINTENANCE FREE BATTERY BANK
1.
SCOPE:
This specification provides for design, Engineering, manufacture, stage testing,
inspection and testing before dispatch, packing, forwarding and delivery at site FOR
destination of 48 Volts 300/120AH SMPS based battery charger suitable for indoor
installation, complete with all fittings accessories and associated auxiliary equipment
mandatory which are required for efficient and trouble free operation as per specified
here under.
It is not the intent to specify completely all the details of design and construction of
equipment. However, the equipment shall conform in all respects to the high standard of
engineering, design and workmanship and shall be capable of performing in continuous
commercial operation up to the Bidder’s guarantee acceptable to the purchaser. The
equipment offered shall be complete in all component necessary for its effective and
trouble free operation along with associated equipment interlocks protection scheme etc.
Such components shall be deemed to be within the scope of supply irrespective of
whether those are specially brought out in this Specification and or the commercial order
or not. All similar parts particularly movable ones shall be interchangeable.
1.02
1.03
1.04
CLIMATIC CONDITIONS :
The equipment to be supplied against the specification shall be suitable for satisfactory
continuous operation under the following tropical conditions:
Max. ambient air temperature
Max. daily average ambient temperature
Max. yearly weighted ambient temperature
500 C
450 C
350 C
Min. air temperature
Max. humidity
Min. relative humidity
Average number of thunder storm days per annum
Average annual rain fall
Number of months during which tropical monsoon
conditions prevail altitude above MSL
(-) 50 C
100%
26 %
40
15 cm to 100 cm.
4 months (June to
Sept). Varies from 61 meters to
815.00 mtrs.
120 days
0.3g.
Heavy
1.0 KW/sq.m.
195 kg/sq.m.
Average number of rainly days per annum.
Seismic level (Horizontal acceleration)
Degree of pollution
Intensity of solar radiation
Max. Wind load
STANDARD:
All material and equipment shall comply in all respect with requirement of the latest
addition of the relevant IS/IEC/TEC/RDSO. A set of standards adopted, translated in
English, if it is in language other than English, shall also be enclosed with the tender, to
enable due comparison, wherever a standard is specially mentioned in these
specification. It is understood that the corresponding standard amongst the sources
mentioned above shall also apply.
MANUFACTURE AND WORKMANSHIP:
All the material used in the construction of the equipment shall be of the best quality
obtainable of their respective kinds and whole of the work shall be of the highest class,
well finished and of approved design and make. Casting shall be free from blow holes,
flaws and of the true form and dimensions.
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All machined surfaces shall be true and smooth and well finished.
1.05
DUTY AND GENERAL ARRANGEMENTS:
The power for the charging apparatus shall be given through an independents 4-core
cable connection from an A.C. 50 cycles 3 phase 415 ± 10% volts switchboard fed from
a Station Transformer.
1.06
GENERAL TECHNICAL REQUIREMENT:
The battery chargers of 48V/25Amp. in N+1 configuration with ultimate capacity
50Amp/75 Amp/100Amp shall be of SMPS type with positive earth. The system shall
consist of a Distribution/Switching/Alarms arrangement (DSA) and Float Rectifier-cumChargers (FR/FCs) in a rack. It shall employ modular configuration for flexible provision
of DC Power. It shall employ menu driven Micro Processor Controlled Techniques for
DSA as well as module for control, monitoring and alarm to achieve better reliability of
the system. The SMPS battery chargers shall be capable of continuous operation with
float voltage 2.23 to 2.25 Volts per cell (at 27 Deg. C) and 2.3 Volt per cell (at 27 Deg C)
for charge voltage while supplying the constant DC load
1.06.1 The SMPS battery chargers shall have constant voltage characteristics throughout the
range (from zero to full load) at the floating value of the voltage so as to keep the
maintenance free type VRLA batteries fully charged but without harmful overcharge.
The system shall employ a modular configuration to provide flexibility in view the future
load requirements of DC power. The modules shall be accommodated in a rack.
Distribution/Switching/Alarm (DSA) shall be provided in first rack or in a separate rack as
per manufacturer’s design for the ultimate system capacity. All factory wiring for the rack
shall be for the ultimate capacity so that only plugging of FR/FC module shall enhance
the DC power plant output.
1.06.2 Principal Parameters: Input Nominal Voltage
i) 230 Volt +/-10% AC single phase for module of
25Amp.For ultimate capacity of 50Amp
ii) System rack having ultimate capacity of 75 Amp and
125Amp will be provided AC Three phase input power
supply and each module shall operate on individual
phase of three-phase AC input power supply.
Input Voltage Range
165V to 260 V AC
Frequency
48Hz to 52Hz
Power factor
>0.98 at 50% and above load
Efficiency
>0.90 at 50% and above load
Soft Start time
10 sec Min output current ramp up
Output Voltage adj.
48V to 56V DC
Current limit adjustable
For 50Amps SMPS
5 to 50A
Current limit adjustable
For 25Amps SMPS
5 to 25A
Regulation:
1)
Output
voltage +/-5% of DC output voltage for any load of 25% to 100%
over shoot/under shoot
when charger is switched
on
+/-5% of DC output voltage for any load of 25% to 100%
2)
DC output voltage
over shoot for a step
change in AC voltage
165V to 260V single +/-5% of DC output voltage for any load of 25% to 100%
phase
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1.07.
3)
DC output voltage
for a step load change of
25% to 100%
Ripple
<200mV RMS
Load Sharing
Better than +/-5% active current sharing at full load
Cooling
Convection
Main Features of SMPS Charger
1.07.1 CONSTRUCTIONAL FEATURES:
The rack structure shall be made up of rigid frame work of steel profiles and rear door
may be of hinged or removable type. The rear door shall be provided with ventilation
arrangement. Alternate design of aluminum and other rigid structure meeting the
requirements are also permitted.
The rack shall be free of sharp edges or sharp corners. The rack shall be designed for
easy maintenance & installation. The rack mounting arrangement shall be such as to
provide easy access from rear and top for installation and maintenance.
The individual FR/FC module shall be easily mounted to/removed from the front side of
the rack. The FR/FC module shall be designed to slide in to the rack on a suitable
mechanical arrangement. The associated AC input, DC output connections,
control/systems & interface cable connecting the modules shall be connected
/disconnected easily without causing any interruption in the supply and damage to load
or other working module.
Proper thermal engineering of hardware design shall be done by the manufacturer so as
to ensure the uninterrupted use of the equipment. The rack complete with all panels
fitted shall be designed to allow cooling by natural convection.
With the doors in position, all the common visual alarms and meters shall be clearly
visible. However the fixtures on the door shall not restrict the movement of door in any
way.
The FR/FC modules shall be cooled by natural convection. AC input to FR/FC shall be
through locking type arrangement. DC output shall be through hot plug in connector on
the FR/FC side and through lugged termination on the bus bar/termination end. Control
alarm and mentoring connection shall be through connectors. The FR/FC module shall
be removable from the rack only. All AC input, DC output & alarm/control/monitoring
cables interconnecting the modules and rack shall be easily disconnected by plugs or
connectors.
AC Terminations
The input terminal should be single phase or three phases as the case may be cleared
marked as R Y B and N and for AC three phase, L and N for AC single phase.
AC input termination shall be suitably protected against the accidental touch/contact with
the working staff for their protection and shall also have clear and prominent be “Danger”
marking. Screening shall be provided between AC and DC components to prevent
accidents.
The AC input connection to the rectifier module shall be by means of locking type plug
and socket arrangement. All the connection between distribution and FR/FC shall be
through proper rated cables only. Fuses and circuit breakers for each FR/FC shall be
easily accessible and properly rated. Proper termination for the AC input of the circuit
breakers and its output to the FR/FC.
The system racks having ultimate capacity of 100 Amp. will be provided AC three phase
input power supply and each module shall operate on individual phase of three phase
AC input power supply.
DC Terminations
The output of each rectifier in the negative load shall be taken through full rated ISI
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marked MCBs. All the AC, DC control & alarm cabling shall be supplied with the rack.
All DC +ve and - ve leads shall be clearly marked.
Wiring
All insulated conductors except those within the confines of a printed circuit board
assembly shall be of the rating enough to withstand the maximum current and voltage
during fault and overload. All the wires and cables used shall be fire retardant as per IS
1554 with amendment I (June 94).
All wiring shall be neatly secured in position and accurately supported. Where wires
pass through any part of metal or cover the holes through which they pass shall be
suitably bushed.
Earthing: Two power earth terminals shall be provided in the frame of the system.
Mounting off component & layout:
Components mounting and fixing methods shall be secured. Suitable mechanical
structure/ arrangement for holding modules in position shall be provided so that the
module is held firmly by sliding through it.
The FR/FC modules shall be cooled convection. AC input to FR/FC shall be through
locking type arrangement. DC out put shall be through hot plug in connector on the
FR/FC side and through lugged termination on the bus-bar termination end. Control,
alarm and monitoring connections shall be through connectors.
The FR/FC module shall be removable from the front of the rack only. All
AC input, DC output and alarm/control/monitoring cables interconnecting the modules
and racks shall be easily disconnected by plugs or connectors.
1.07.02 Distribution, Switching, Control, alarm & Monitoring (DSA)
The Distribution Switching sub - system of DSA shall preferably be in the modular from
whereas control, alarm &, monitoring sub-system shall only be modular. The Controller
must be Microprocessor based. The distribution switching sub-system 'may be
accommodated in a rack with other FR/FCs or in separate rack. These sub systems
shall be rack mountable. DSA shall preferably be housed in the upper portion of the rack
above the FR/FC modules. The unit shall be equipped to meet the ultimate system
capacity.
1.07.03. Battery Temperature Compensation.
The charger shall be provided with the appropriate circuitry to interface with the
temperature probe assembly. With the probe, the charger shall automatically
compensate gassing and constant voltage setting inversely proportional to the probe’s
temp/ battery ambient temp., so that over charging at high temperature and under
charging at low temperature can be prevented.
1.07.04 Current Limiting (Voltage Drop)
Current Limiting (Voltage" Drop) shall be provided for float/ charge operation. The
float/charge limiting shall be continuously adjustable between 50% to 100% of rated out
put current for out put voltages range of 44.4 to 56 volt. For test purposes upper limit of
100% +5% and lower limit of 50% - 5% shall be acceptable. The float and charge current
limit adjustment shall be provided on the front panel of the rectifier module. The FR/FC
modules shall be fully protected against short circuit. It shall be ensured that short circuit
does not lead to any fire hazard.
1.07.5 Fuses
All fuses shall be HRC Link type. Fuses shall be mounted on fuse carriers which are in
turn mounted on fuse bases. Wherever it is not possible to mount fuses on carriers,
fuses shall be directly mounted on plug-in type base. In such case one insulated fuse
pulling handle shall be supplied for each charger. Fuse rating shall be chosen by the
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Bidder depending on the circuit requirement. All fuses in the chargers shall be
monitored. Fuse failure annunciation shall be provided on the failure of any fuse.
1.07.6 Blocking Arrangements
Blocking arrangement shall be provided in the positive pole of the out put circuit of the
charger to prevent current flow fr9m the DC battery into the charger.
1.07.7 Monitoring, Alarm and Indicating Lamps.
The visual indications/ display such as LEDs, LCDs or a combination of both shall be
provided on each FR/FC module to indicate:
(A)
Functional indications:
The following functional indications shall be provided on FR/FC and DSA:
a) Mains available.
b) FR/FC on Auto Float.
c) FR/FC on Auto charge.
Note: The functional indication (a) shall be provided on both DSA & FR/FC module. While b
and c may be provided either on DSA or both FR/FC & DSA.
(B)
Alarm indications
(i) On FR/FC
(a) FR/FC over voltage, under voltage or output fail.
(b) FR/FC over load (voltage drop)
Functional indications shall be extended as status and alarm. FR/FC fail to distribution /
switching / control & alarm unit.
(ii) On DSA
a)
Load voltage high (above 56v /low (below 45.6 v)
b)
FR/FC fail
c)
Mains out of range
d)
System Over Load
e)
Mains ON/Battery Discharge
f)
Temp. Compensation fail
g)
Battery Fail or No Battery
h)
Battery Isolated from the load
All alarm circuits shall be provided with suitable delay to ensure that they do not operate
to transient. All the protection /alarm shall be within tolerance of O.25v in case of DC
voltage and 10/0 in case of current. For AC voltage it shall be +/- 5V.
Every alarm, condition shall be accompanied with an audio alarm with audio cut off
facility.
Potential free contacts two (one for alarm and one redundant) shall be provided for
extension of alarms to centralized display. .
1.07.8 Radio Interference
The equipment shall be efficiently screened against interference to radio and also other
communication equipment, which may be installed in the same building. All sources of
noise shall be filtered if necessary with suppressors generally in accordant with relevant
standards.
1.07.9 Name plates and marking
The name plates shall be while with Black engraved letters. On top of each charger, on
front as well as rear sides, larger and bold name plates shall be provided to identify the
charger.
Name plates with full and clear inscriptions shall also be provided on and inside of the
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panels for identification of the various equipments and ease of operation and
maintenance.
An etched, engraved or anodizer name plate shall be fitted on each $MPS battery
charger unit having following details inscribed.
Manufacture's name.
P.O . No. & date.
S.No. of SMPS unit
Rating of SMPS charger
Input voltage of SMPS charger
Output voltage of SMPS charger
Year of Manufacture
8.0 RESPONSIBILITY FOR DESIGNS:
The contractor shall assume full responsibility for co-ordinate and adequate design and
shall conform to the best engineering practice for the operating conditions specified. In
case the equipment covered by this specification is to be co-ordinate with other
equipment, the contractor shall furnish complete information and data as may be desired
by the purchaser.
9.0 TESTS & INSPECTION:
The tenderer must furnish test reports carried out on one of the SMPS battery charge
unit which shall pass all the prescribed type tests for conformity of relevant standards.
These type test reports must be issued by a Govt. approved / Govt. recognized/ a Govt.
accredited laboratory and must not be older than 7 years from the date of opening of
tender.
Routine/ acceptance tests shall also be carried out on each SMPS Battery Charger as
per specification. Following type tests shall be carried out for compliance of specification
requirements:
TYPE TESTS:
(I)
(II)
(III)
(IV)
(V)
(VI)
(VII)
(VIII)
9.1
Visual Inspection
Insulation Resistance Test
Applied high Voltage test.
Performance test.
Test for protection device.
Burn in test.
Climatic test.
Vibration test.
ROUTINE & ACCEPTANCE TESTS:
On each of the SMPS battery chargers following routine and acceptance tests shall be
carried out at manufacturer's works before dispatch.
(I)
(II)
(III)
(IV)
(V)
Visual Inspection
Insulation Resistance Test
Applied high Voltage test.
Performance test.
Test for protection device & other tests shall be carried out as per requirement of
GTP in the presence of inspecting officer.
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9.2
a)
b)
c)
d)
INSPECTION:
The inspection of the equipments shall be carried out by the purchaser's representatives
in accordance to the relevant standards.
The purchaser shall have access at all times to the works and all other places of
manufacture, where the equipments are being manufactured and; the supplier shall
provide all facilities for unrestricted inspection of the Supplier's works, raw materials,
manufacture of the material and for conducting necessary tests at any stage.
The supplier shall keep the purchaser informed in advance about the manufacturing
program so, that arrangements could be made for inspection.
No equipments shall be dispatched from its point of manufacture unless the material has
been satisfactorily inspected, tested and cleared.
Inspection and acceptance of any quantity of equipment shall in no way relieve the
Supplier from his responsibility for meeting all the requirements of this specification and
shall not prevent subsequent rejection if such equipment is later found to be defective.
9.3
TESTS AT SITE: The purchaser reserves the right to conduct all the tests on the equipment after arrival at
site and the supplier shall guarantee test certificate figures under actual service
conditions.
10.
DRAWINGS, LITERATURE AND MANUALS:
In addition to any other drawings which the tenderer may like to submit lo show the
arrangement and merits of the offered equipments. The following drawings shall be
supplied with the tender.
General installation layout of SMPS equipments showing position of all associated
equipments.
Detailed dimensional drawings and descriptive literatures of all the associated
equipments separately.
Circuit wiring diagram and schematic diagram.
Literature/ pamphlets / manuals of SMPS and its associated equipments.
i.
ii.
iii.
iv.
The successful tenderer shall within four weeks of placement of order, submit four sets
of final version of all the drawings of the SMPS Battery Charger for purchaser’s
approval. The purchaser shall communicate his comments/approval on drawings to the
supplier within a period of four weeks. The supplier shall if necessary modify the
drawings and resubmit three copies of modified drawings for purchaser’s approval within
two weeks from the purchaser’s comment, which will be approved within 15 days. After
receipt of purchaser’s approval the supplier shall submit four sets of drawings and
literature containing erection, operating and maintenance instructions per equipment. A
set of reproducibles of the approved drawing too will be supplied for the purchaser use.
11.
i.
ii.
iii.
iv.
PACKING & MARKING
All SMPS equipments shall be packed in strong seasoned wooden crates to avoid
handling problem.
The packing shall be of sufficient strength to withstand rough handling during transit,
strong at site and subsequent handling in the field.
Suitable cushioning, protective padding, or dunnage or spacers shall be provided to
prevent damage or deformation during transit and handling.
All packing cases shall be marked legibly with the appropriate caution symbol and
correctly so as to ensure safe arrival at their destination and avoid dispatched on
account of faulty packing and faulty or illegible markings stenciled on it-in indelible ink.
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v.
Whenever 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 supplier
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 instruction.
All gauges, meters, instruments etc. shall have dials or scales calibrated in metric
system of units. All name plates, instruction plate, warning signs and any marking
what-so-ever on the equipment and its parts and accessories shall be in Hindi-English
Language, using idioms, words and meaning as in current use in India.
In order to facilitate sorting and erection at site every part of the plant and equipment
shall be suitably marked.
12.
PLACE OF MANUFACTURE AND INSPECTION:
The tenderer shall state in his tender the place(s) of manufacture, testing and inspection
of the various portions of the work included in the tender. The purchaser or his duly
authorised agent shall have access to the contractor's or sub contractor's work at any
time during working hours for the purpose of inspecting the manufacture and testing of
materials, equipment and completed plant and the contractor shall provide the
necessary facilities for inspection.
13.
DEPARTURE FROM SPECIFICATION:
Should the tendered wish to depart from provision of this specification either on account
of a manufacturing practice or for any other reasons, he will draw special attention to the
proposed points of departure in his tender and submit such full information, drawings &
specifications as will enable the merit of his proposal to be appreciated.
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APPENDIX ‘A’
SCHEDULE OF REQUIREMENT
Battery Charger:
The Battery Charging equipment shall be housed in a sheet steel cabin finished in stove
enameled light grey color conforming to shade of 631 of IS-5 specification. The charger
cabin shall have thickness of 18 gauge or better with adequate ventilation. The minimum
size of cubical should be 585mm Width, 500mm depth and 560mm Height. The rack
shall be free of sharp edges or sharp corners. The rack shall be designed for easy
maintenance & installation. The rack mounting arrangement shall be such as to provide
easy access from rear and top for installation and maintenance. Two power earth
terminals shall be provided in the frame of the system to provide effective earthing to the
system.
The individual Rectifier module shall be easily mounted to/removed from the front side of
the rack. The Rectifier module shall be designed to slide in to the rack on a suitable
mechanical arrangement. The associated AC input, DC output connections,
control/systems & interface cable connecting the modules shall be connected
/disconnected easily without causing any interruption in the supply and damage to load
or other working module. There should be auto/manual change over between float and
boost charger.
Charger Section:
The charger should be suitable for operation from single (230 ± 30% volts, 50Hz) or 3
phase (415 ± 30% volts, 50Hz) AC supply as per the system ultimate capacity and
suitable for charging 24 cell at 2.16 to 2.40 per cell while simultaneously supplying a
continuous load as per requirement at an ambient temp. of 45⁰C. The output of charger
should be stabilized within 1% of the charging voltage. There should be individual MCB
for each module and complete system. The charger section shall comprise of the
following items:
S No. Item Description
Qty
1.
Cabinet
1
2.
Hot Swap Rectifiers Modules 25A/48V
N+1
( N = Load Current +
Battery Charging Current)
The rectifier Modules shall be hot swappable with Individual Alarm Indications for Over
Voltage/ Under Voltage or Output Fail.
3
Dropping Diode
During the Boost charging the full battery voltage should not be reflected on the bus
bars, that is, it should be ensured that the constant voltage is available on DC bus bars
irrespective of the fact whether the battery is on float or on boost charge and at same
time all battery cell should be equally charged. There should be auto/manual change
over between float and boost charger.
4
Voltage monitoring Card
1
5
AC Contactor
1
6
DC Contactor
1
7
Low Voltage Detection Card
1
8
MCB 10A
4
9
MCB 64A
2
10
Lightening Protection Device Class C
1
11
Battery temperature Compensation Probe
2m
12
Microprocessor based Controller
1 No
The controller should be mounted so that it is front accessible , front monitored and
Front Controlled. It shall be installed in such a manner that the LCD panel is visible
without opening and Lock / Door of the unit. The controller should have the following
facilities:
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A. Metering :
a) Load Voltage.
b) Load Current.
c) Battery Voltage.
d) Battery Current.
e) Battery Temp.
f) Voltage and current of Individual module.
B. Alarms and Indications :
a) Load voltage high.
b) Single Rectifier alarm
c) Multiple Rectifier alarm
d) Mains out of range
e) System Over Load
f) Mains ON/Battery Discharge
g) Temp. Compensation fail
h) Battery Fail or No Battery
i) Battery Isolated from the load
All alarm circuits shall be provided with suitable delay to ensure that they do not operate
to transient. All the protection /alarm shall be within tolerance of O.25v in case of DC
voltage and 10/0 in case of current. For AC voltage it shall be +/- 5V.
Every alarm, condition shall be accompanied with an audio alarm with audio cut off
facility.
C. Functional Indications:
a)
Mains available.
b)
Rectifier on Auto Float.
c)
Rectifier on Auto Charge.
d)
Alarm to indicate general alarm condition
13.
Potential free contacts:
Potential free contacts should be provided for extension of alarms to centralized display.
a)
Mains out of range.
b)
Single Rectifier alarm
c)
Multiple Rectifier alarm
d)
Communication Error.
e)
System Over Load.
f)
System voltage high.
g)
System voltage low.
All the components should be of best quality and from reputed manufacturers. The
layout of components, wiring workmanship reliability etc. shall be of best quality.
Adequate space should be provided within the charger section and Distribution,
Switching, Control, alarm & Monitoring section for easy accessibility of MCB, Fuses,
Alarms, protection devices etc. The charging equipment should be complete with the
various component listed above but necessarily limited to the same. The charger shall
also be complete with wiring, glands and fixing bolts.
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