Saturday, August 1, 2009


01.00 a)The requirements of Electric Power Supply system are
specified herein on system basis. The contractor shall
be fully responsible for engineering and furnishing a
complete and operational system fully meeting the intent
and requirements of this specification and owner
approved drawings. All equipment and accessories
requires for completeness of this system shall be
furnished by the contractor whether these are
specifically mentioned herein or not. All the
equipments and sub-systems offered shall be from reputed
experienced manufacturer. All system cabinets,
enclosures & distribution boards shall be manufactured,
assembled, wired and fully tested as a complete assembly
as per the requirements of this specification at the
manufacturer's works.

b) Standards and Conformityi)Safety requirement –IEC 62040 Part-I/EN 50091 Part-I
ii)EMC requirement - IEC 62040 Part-II (Class-A)
iii)UPS Test & performance -IEC 62040 Part-III

.02.00 The power supply system shall be designed to meet the
electric power requirements of various C&I systems
including DDCMIS and shall be configured as described

a) For MMIPIS portion of DDCMIS including peripherals
like CRT's. printers, disks etc. and other systems such
as SWAS, panel instruments, requiring stabilized AC
power, the bidder shall furnish a redundant UPS

b) The power supply to each DDCMIS system cabinets is fed
through dual 240 V AC Feeder from UPS.

.03.00 The UPS system in the above mentioned configurations
employed float cum boost chargers, battery banks, static
inverters, static switches. AC/DC distribution boards etc.
shall meet the following specification requirements as a

.04.00 Uninterruptible Power Supply(UPS)System-Design Criteria
The UPS system shall have 2x100% parallel redundant
chargers and inverters, 2x100% battery bank, bypass line
transformers and voltage stabilizer, static switch,
manual bypass switch, AC/DC distribution boards, other
necessary protective devices and accessories and shall
meet the following requirements as a minimum.

(a)The UPS shall conform to IEC-62040.3 and the specification given below, in case of any conflict between the two, most stringent conditions will apply.
(b) The UPS shall be parallel redundant, double conversion (VFI -SS 111).
c) The KVA rating of UPS shall be as required by expected loads and include 10% spare capacity guaranteed at 50 Deg.C Amb. If UPS KVA rating is applicable at a lower ambient temperature than specified 50 Deg.C, the bidder shall consider Derating factor of at least 1.5% Deg.C for arriving at the specified UPS capacity at 50 Deg.C ambient.

(d) The UPS shall have an over load capacity of 125% rated
capacity for 10 minutes and 150% rated capacity for 1 Min.

(e) The inverter shall have sufficient I2t capability to
clear fault in the maximum rated branch circuit.

(f) The sizing of UPS shall be based on the power factor of
the loads being fed subject to a maximum of 0.8.

(2) Each of the redundant chargers & batteries shall meet
the specification requirements.

(3) The UPS system shall be capable of operating without DC
battery in circuit under all conditions of load and the
performance of various components of UPS like inverter,
charger static switch etc. shall be guaranteed without
the battery in circuit.

(4) The UPS system design shall ensure that in case of
failure of mains input power supply to one of the
chargers, the other charger whose mains input power
supply is healthy, shall feed to one or both the
inverters as the case may be as per manufacturer's
standard practice & continue to charge the DC battery at
all load conditions. The bidder should note that this
situation should not in any way load to the discharge of
the DC battery.

(5)(i) Electrical Input of UPS
a) 415 V +/- 10%, 3 Ph
b) 50 Hz +/- 5%
c) THD <> 3 : 1

(viii)Back feed protection as per IEC 62040.1

(ix) Panel (Degree of protection)- IP 41

(x) Redundant Cooling Fans with Monitoring

(xi)a)The winding of transformer shall be electrolyte grade
copper with F Class insulation with temperature rise
limited to Class ‘B’.

b)All isolation transformers shall be as per BS-3535.

.05.00 Static Inverters

(i)a)The static inverter shall be solid state type IGBT
using proven pulse width modulation(PWM) quasi square
wave/step wave technique. The inverter equipment shall
include all necessary circuitry and devices to conform
to requirements like voltage regulation, current
limiting, wave shaping, transient recovery, automatic
synchronization etc. The steady state voltage regulation
shall be +/- 1% and transient voltage regulation(on
application/ removal of 100% load)shall be +/-2%.
Frequency regulation for all conditions of input
supplies, loads and temperature occurring simultaneously
or in any combination shall be better than +/-0.5%
(automatically controlled).

b)The inverter efficiency shall be at least 85% on full load
and 80% on 50% load.

c)The synchronization limit for maintenance of synchronization between the inverter and stand by AC source shall be 48-52 Hz, field adjustable in steps of 0.5 Hz.

d)DC input window of each inverter shall be either 315–434
or 320-450 V DC.

e)Total output voltage distortion (Max) 3% THD (Linear Load
Condition) 5% THD(Non Linear Load Condition).

(ii) Over load, short circuit and load loss
The inverter shall be provided with suitable HRC fuses
at the input and output which will permit proper
coordination with other protective devices and at the
same time protect the inverter against damage due to
internal faults. However, if the Bidder's system
design does not use fuses then the fuse free circuit
breaker may also be permitted provided it meets the
specification requirements. All necessary equipment
shall be provided to protect the inverter against over
load, short circuit and 100% loss of load. The inverter
shall be self protecting against damage if energized
with full load connected.

(iii)Inverter equipment shall include all solid state
circuitry and devices including stable oscillator etc. to
enable inverters to operate satisfactorily in parallel
sharing mode each inverter taking 50% load during
normal operation. In case of failure of either
inverter, 100% load shall automatically be transferred
to healthy inverter without any break and degradation in
the quality of UPS output and disconnecting the faulty
inverter automatically.

(iv)The inverter failure shall be alarmed and the healthy
inverter shall get synchronizing signal from the standby
AC source and remain synchronized within the set
limits. The limits for the synchronization between
healthy inverter and standby AC source shall be field

(v)a)On failure of both inverters, the loads shall be
transferred to standby, AC Power without a break if
within synchronized limit.

b) with break (10 msec. Max.) in case of inverters being out of synchronization limits .

(vi)Bidder shall provide isolation transformer after each inverter and before Static Switch.

.06.00 Static Switch and Manual Bypass Switch

The static switch shall be provided to perform the
function of transferring UPS loads automatically without
any break from (i) faulty inverter to standby AC source
in case of failure of both the inverters and (ii)from
faulty inverter to standby AC source in case of failure
of both the inverters. Manual bypass switch shall be employed for isolating the UPS during maintenance.

.07.00 Step Down Transformer and Voltage Stabilizera)The transformer shall be of low impedance type and the
rating shall be such that extremely fast fault clearance
is achieved, even in the largest rated branch circuit.
The over load capacity of the transformer/ stabilizer
shall not be less than 300% for 200 ms. The stabilizer
shall employ silicon solid state circuitry and the
output voltage regulation shall be +/- 2%. The
efficiency of the stabilizer shall be 95% or better.
b)The winding of all transformer shall be electrolyte grade
copper with ‘F’ Class insulation and Temperature rise up to ‘B’ Class.

.08.00 (1) Float cum boost chargers:
a)Bidder shall provide 2x100% redundant chargers. The each charger Shall sized to meet the 100% load requirements of the control system plus recharge the fully discharged battery within 8 hours.

b)The chargers shall be self regulating, solid state
silicon controlled,12 pulse full-wave rectifier type
designed for single and parallel operation with battery
& shall have automatic voltage regulators for a close
voltage stability even when AC supply voltage and DC load
fluctuates, effective current limiting features and
filters on both input and output to minimize harmonics.
The charger output regulation shall be +/- 1% from no
load to full load with an input power supply variation
of +/- 10% in voltage and +/- 5% in frequency.

c)Bidder shall provide line filters and 12 pulse rectifier/ IGBT to achieve TDH less than 8% at charger input.

d)In addition to alarms on charger panel, potential free
contacts for alarms like charger O/P voltage high etc.
shall also be provided for use in DDCMIS. Further
isolated 4-20 mA signals shall be provided for important
parameters like charger voltage etc.

(2) Batteries
a)The batteries shall be heavy duty Lead Acid PLANTE type
and shall be sized for one hours of full load operation.
The PLANTE Lead Acid batteries shall conform to IS:1652.

b) The battery shall be sized considering following parameters –

(i) Minimum Amb. Temp. 1.6 Deg.C .
(ii) End Cell Voltage 1.85 v .
(iii) Aging Factor 1.2 ,
(iv) Design Margin of 15% .

c)The procedure for estimate battery capacity at 27 Deg .C and shall be as per guidelines stipulated in IEEE standard 485.

d)The racks for supporting battery cell shall be
constructed of teakwood, painted with at least three
coats of anti acid paint. The racks shall be free standing type on porcelain insulator.

e)Bidder shall consider voltage drop of 4 V(Max)in battery
cable,(Battery to Charger)while sizing the battery & Cable.

d)Battery Health Monitoring System (BHMS)BHMS shall include microprocessor based hardware and software to monitor the condition of each battery cell of UPS battery banks on-line. With BHMS it shall be possible to measure & analyze the minimum and maximum voltage values of each battery-cell so that any damage to battery shall be prevented by pro-active maintenance. BHMS shall communicate with the Controller and provide alarms as finalized by Employer during detailed engineering.
.09.00 AUXILIARY EQUIPMENTSAll required auxiliary equipment/materials as finalised
during detailed engineering shall be furnished with
each charger/inverter/ battery bank and shall include as
a minimum various meters(AC/DC voltage /current, KVA
power factor, frequency meters etc., circuit breakers,
selector switches, push buttons indicating lights,
ground detector system, battery accessories like inter
cell connectors, inter step connectors, battery racks
etc.)further, isolated 4-20 mA signals for important
parameters and potential free contacts for important
alarms shall be provided for use in DDCMIS.

.10.00 Bidder shall furnish the power supply distribution
scheme, single line diagram, all calculations such as
charger/inverter rating calculations, battery sizing
calculation etc., during detailed engineering for
owner 's review and approval.

.11.00 GENERALa) A C Distribution Board
The Bidder shall provide 2x100% AC distribution board. However 25% spare feeder (Minimum 1 No.)with fuse for each rating shall be provided.
b) Bidder shall provide earthing as per Indian standard/NEC.
(a) Redundant cooling equipment(2x100%) shall be furnished for each assembly. Reserve fan capacity shall be equal to 100 percent of cooling fan requirements for full load operation with only one bank of rectifier/inverter in service at the specified maximum ambient temperature.
(b) Completely independent duplicable wiring and control systems shall be provided for the normal cooling fan system and the reserve cooling fan system.
(c) Each cooling fan shall normally run continuously and shall be powered from the output of the inverter whose enclosure it serves (for cubicles housing inverters). For other cubicles, fan power supply shall be as finalised during detailed engineering. Each cooling fan supply circuit shall be separately fused.
(d) Each cooling fan shall be equipped with an airflow switch for monitoring & alarm.
.12.00 Bidder shall provide following minimum accessories per Battery set for maintenance of battery and safety equipment for maintenance personals.
a) Hydrometer - 5 Nos.
b) Thermometer - 5 Nos.
c) Cell Tester(Voltmeter) - 5 Nos.
d) Alkali Mixing Jar - 5 Nos.
e) Rubber Apron - 5 Nos.
f) Rubber Gloves - 5 Pair
g) Set of Spanners - 5 Pair
h) Spare acid in Container - 25% of Total acid
i) Other accessories as per
Recommendation of Battery manufacturer

j) Specific gravity correction chart - 2 Nos.
k) Cell Lift Facility - 1 No.
l) discharge resistance - 1 No.

.13.00 U P S TESTING.13.01 Factory Acceptance Test- (as per IEC 62040-3)
The following shall be constitute the Factory Acceptance
Test (FAT) to be conducted as minimum but not limited to -
a) Light Load Test
b) UPS Auxiliary Device(s)Test
c) Synchronization Test
d) A C Input Failure Test
e) A C Input Return Test
f) Simulation of parallel redundant UPS fault Test
g) Transfer Test
h) Full Load Test
i) UPS Efficiency Test
j) Unbalanced Load Test
k) Balanced Load Test
l) Test of current Division in parallel redundant UPS
m) Over load capability Test
n) Short Circuit Test
o) Short Circuit Protection device Test
p) Restart Test
q) Output over voltage Test
r) Periodic output voltage variation Test
s) Frequency variation Test
t) Harmonic components measurement

The above test shall be witness By owner / Owner’s

.13.02 Type TestBidder shall submit following Type Test Report along with
final acceptance report.

a) Battery as per IS – 1652
b) UPS/ Charger
i) IP degree
ii) Type Test as per IEC 62040.3.

.13.03 Bidder shall submit following documents along with factory acceptance test (FAT) Report –
a) Internal Test Report along with heat run test report.
(48 Hrs. at 50 Deg.C + 120 Hrs. at Amb. Temp.)
Transformer winding temp measurement shall be by change in resistance method.
b) Calibration certificate of measuring instruments.
c) Routine Test as per IEC 62040.3
.13.04 . Testing at site

Full load test shall be demonstrated after commissioning of UPS and charger with batteries at site as per IEC 62040.3.
.13.05 All above test shall be conducted as per IEC 62040 Part-3.

9 .

VENDERS -lead acid plante

2.HBL Nife , hyderabad  

UPS standards

IEC 62040-1 Generals and Safety
IEC 62040-2 EMC
IEC 62040-3 Testing and Performance
IEC 60950-1 ITE Safety
IEC 60146-1 Semiconductor converters
IEC 60146-2 Inverters
IEC 60439 Switchgear Assemblies

Nuclear Power Plant specific IEC standarts
IEC 60780 Electric equipment, Qualification
IEC 60880 Software for computers
IEC 60980 Seismic qualification
IEC 61225 Electrical Supplies for Safety

UPS IEEE standardsIEEE 944 Application and Type Testing

Nuclear Power Plant specific IEEE standartsIEEE 323 1E Equipment, Qualification
IEEE 344 Seismic Qualification
IEEE 650 Chargers and Inverters, Qualification

UPS NEMA standardsPE 1 Generals and Performance Testing
PE 5 Battery Chargers

UPS UL standardsUL 1778 Safety ( )

Nuclear Power Plant GOST standardsPNAE G-9-027-91 Design, Emergency Power Systems
PNAE G-5-006-87 Design, Seismic Resistance