DRAFT Specification No……..
lR;eso
t;rs

GOVERNMENT OF INDIA
MINISTRY OF RAILWAYS
SPECIFICATION FOR GUIDELINES TO SET-UP THE TEST
BED OF TESTING OF REPAIRED/OVERHAULED 3-PHASE
TRACTION MOTORS OF WDG4 / WDP4 LOCOMOTIVES.
FEBRUARY 2011
Issued by
Motive Power Directorate
Research, Designs and Standards Organisation
Manak Nagar, Lucknow-226011
1.0
Introduction
ALCO locomotives are rebuilt at DMW/PTA. It has been decided that repairing/
overhauling of traction motors for 4000/4500 hp AC-AC WDG4 and WDP4
locomotives are also to be carried out at DMW/PTA. In view of this test facilities shall
be required to verify the characteristic of these repaired /overhauled traction motors.
A general guidelines for installation and commissioning of test bed for testing of
repaired/overhauled traction motors of WDG4/WDP4 locomotives at DMW/PTA have
been framed.
Objectives:
2.1
This guidelines covers the technical requirements for setting-up the test facilities for
conducting routine testing of 3-phase traction motor type 1TB2622 and ITB2525 of
M/s Siemens make or equivalent Traction motor of other manufacturers used in 3phase Diesel Electric Locomotives of Indian Railways. The scope of technical
requirement of this guidelines covers the design, manufacturing, supply and
commissioning of the equipment for test set-up at DMW/PTA for conducting routine
testing of the motor. The system should be suitable to deliver 2500V to test the
motor. Specified schematics for test set-up in given in Annexure-I.
2.2
The proposed test bed shall be such that the existing set-up shall be suitable for
ROUTINE TEST comprising of short duration temperature rise test, No-Load test,
short circuit test, vibration test & Noise test etc. as per IEC 60349-2 of above said
motors under uncoupled conditions without any modification in the existing ones. The
test parameters of already tested motors is given at Annexure-II for reference
2.3
At a latter date, if it is required to upgrade the test bed, for conducting full load test
(Part of type test as in IEC) it should be possible to do so by minimum adjustment in
the existing set-up and by commissioning of additional equipment along with various
interfaces. In that case the test bed shall be comprised of four quadrant active front
drive during upgradation for load tests. The test parameters at testing (Part of type
test) of already tested motors is given at Annexure-III for reference.
2.4
The equipment required for carrying load test (Part of type test as in IEC) of the
motors shall be taken up in 2nd phase after successful completion of the project for
conducting routine testing of the motors.
2.5
The offered equipment shall be designed to comply with the latest issues of the
appropriate International Electro-technical Commission Standards (IEC) or Indian
Standards (BIS) standards. The same may be indicated in the offer.
3.0
Scope of Supply:
3.1
This guidelines defines the supply of transformer and their associated auxiliary
equipment / accessories, off-circuit tap changer and earthing bus bars. The
successful tenderer shall supply the necessary equipment and undertake the testing
and commissioning of the test bed on turnkey basis.
3.1.1
The scope of Transformer include s:
• The tap changer
• The marshalling kiosk
• The Primary phase CTs
• The Primary neutral CTs
• The Secondary neutral CTs
• All multicore / multipair cabling between those items
• All multicore / multipair cabling between other equipment such as WTI’s, cooling
pumps and fans.
The Primary and Secondary currents should be indicated with appropriate meters.
3.1.2
The scope will also include the provision of separate Earthing connections to the
main tank, each cooler bank, the Primary neutral Earthing connection, cocoordinating rod Earthing connections, the Secondary neutral Earthing connection for
the transformer.
3.2
This guidelines also defines the supply of VFD drive suitable for driving the 3-phase
Motor to be tested rating upto 1.4MW / 2.5KV. It shall also consist of control desk,
from which the control of all the testing parameters can be controlled, monitored /
measured and recorded.
3.3
Switchgear Equipment: Since the supplier has to supply the test bed on turnkey
basis, the supplier shall supply suitable switchgear equipment for satisfactory
operation and protection of the overall system.
3.4
Surface Plates for Traction Motor Test Bed to be supplied by the tenderer.
3.5
Cables and Cable accessories to connect all the equipment under the scope of
supply of tenderer. Distance from supply points to the equipment & test plant shall be
provided by DMW.
3.6
Instrumentation

Power Analyzer

Insulation Tester

High Voltage Tester

Multimeter(s)

Temperature Scanner

Tachometer with speed sensors

Vibration Measurement meter

Noise Level Meter

DC Current Source

1-ph Variac of 28-Amps & Current source of 50 Amps, having voltage, and
current measuring instruments
4.0
Transformer
4.1
References

IEC 60529: Degrees of Protection Provided by Enclosures

IS 2026-1: Power transformers: Part 1 (General)

IS 2026-2: Specification for power transformers: Part II Temperature-rise

IS 2026-3: Specification for power transformers: Part III Insulation levels and
Dielectric tests

IS 2026-4: Specification for power transformers: Part IV Terminal markings,
tapings and connections
4.2
Definitions

CMR - Continuous Maximum Rating – capable of delivering the maximum applied
load constantly

Primary - The high voltage winding of the transformer and any components (e.g. CTs,
Bushings) associated with it.

4.3
Secondary - The low voltage winding of the transformer and any component (e.g.
CTs, Bushings) associated with it.
The Input voltage System: The
indicative
rating/requirement
of
the
transformer proposed for the test-set up is furnished as below. The tenderer
may offer its own design to cater to the requirement during in the offer.
System Voltage (available at input supply from SEB):
11 kV
Rated Voltage
:
12 kV
• Size of step
:
5%
• Nominal position Tap
:
3%
• Number of tapping positions
:
5%
Rated Frequency
:
50 Hz
Design Fault Levels 3ph
:
25 kA for 1 Sec
Design Fault Levels Ph-E
:
25 kA for 1 Sec
Rated lightning impulse-withstand voltage (peak value) to earth:
95 kV
Minimum Electrical Clearances
Basic electrical clearance (Phase-Earth)
:
160-mm
Phase to Phase clearance
:
250-mm
Insulation height (Pedestrian access)
:
2440-mm
Safety working clearance (vertical & horizontal):
2600-mm
4.4.1
Requirement of the Transformer:
4.4.1
Technical Conditions:
.1
The transformer shall be converter duty with one winding in the primary side & multiwinding phase shifted at secondary, suitable to feed the VFD, required to test the
motor.
.2
The transformers shall be suitable for installation outdoors and shall comply with IS2026. Cooling shall be type ONAN / OFAF or ONAN / ONAF. The design of
accessories shall be coordinated so that the thermal rating of the unit shall not be
limited by these accessories.
.3
Transformers under this guidelines shall be suitable for frequency range between
20Hz to 70Hz to test the motor, three phase units with electrically separate Primary
and Secondary windings. They shall typically have a combination of natural / forced
cooling.
.4
The windings shall be able to withstand without damage the thermal and dynamic
effects of external short circuit levels. The transformer shall be designed to ensure
that leakage flux does not cause overheating in any part of the transformer.
Avoidance of over-fluxing at the most onerous operating conditions, especially on
cyclic overloading condition, is essential.
.5
Rated Power: The temperature rises associated with maximum power ratings and
overloads for 11.5 kV, suitable voltage to run the motor under test, transformers are
expected to be within the limits specified in IS: 2026. The designs submitted should
comply with the temperature rise limits specified in IS:2026, Part 2, when operating
under ONAN and OFAF (or ONAF) conditions on any tapping position. Control of
Voltage shall be done using an off-load tap changer.
.6
The guaranteed losses of transformer shall be stated in the tender. These losses
shall also be considered during evaluation of the tender.
.7
Creepage distances shall be a minimum of 25mm per kV at the rated voltage.
4.4.2
General Conditions:
.1
The equipment shall be compliant with IS-2026 Power Transformers where
appropriate unless otherwise varied in tender document. Any variations from this
Standard shall be listed.
.2
The transformer and all associated components shall be designed to be suitable for
use at the defined cyclic rating, without exceeding any defined parameters, at an
ambient temperature of 45 degrees C.
.3
The transformer and all the ancillary equipment (e.g. CTs, instruments etc.) forming
part of the transformer of similar design shall have been type tested by the
manufacturer or testing authority in accordance with the relevant IS or IEC standards
before delivery. Copies of the relevant type test certificates shall be submitted with
the offer.
.4
The transformer shall be supplied with suitable and sufficient anchorage points
(painted yellow) for the attachment of work positioning and fall arrest lanyards for use
when working at height.
.5
All labels shall be clearly visible from the normal operating position and shall indicate
the function of the component, not merely a reference number. The transformer and
all connections shall be capable of operating at any tapping position on load.
.6
Manuals shall be provided which clearly indicate any special considerations and
procedures for use, maintenance, trouble shooting etc.
.7
The normal operating condition of transformers on the power system is to maintain
the secondary voltage constant for either, variations in load on the secondary
winding, or variations in voltage applied to the primary winding. (i.e. to boost the
voltage by operating the tap changer).
.9
Tap changers shall provide facilities for remote tap position indication, tap change in
progress indication and tap-change raise and lower complete indication.
.10
Cable boxes: The transformer shall have cable boxes at both the primary as well as
secondary windings
.11
Open Terminal Bushings: On primary winding unit, the HV terminations shall
usually be outdoor bushings, with a smaller bushing insulator for the Primary neutral.
The Tenderer must specify the types of bushing to be used. On primary winding unit
the primary neutral is not bought out as its insulation level is uniform.
.12
Marshalling Kiosk: The Marshalling Kiosk will provide the point at which all alarms,
trips, controls, indications, and CT outputs from the main transformer, the earthing or
auxiliary transformer and the pump are terminated and ferruled ready for connection
with multi-cores to the relay panels. A tank mounted or cooler support structure
mounted weatherproof local marshalling kiosk is required on transformer. Paint finish
to be the same as the main transformer.
.13
Cooling System: The arrangement of cooling systems should be normally either
ONAN/OFAF or ONAN/ONAF types. Coolers are required with detachable radiators,
valves for oil filtering, motors, fans, pumps, and related control gear associated with a
forced cooling system.
5.0
Variable Frequency Drive (VFD):
Variable speed AC drive also referred as Variable Frequency Converter (VFC) or
Variable Frequency Drive (VFD) or Variable Speed Drive (VSD) is used for
converting ac input power into a controlled output variable ac voltage or current of
variable frequency of 3-phase Induction motor testing.
Power Converter and Inverter: It shall consist of line side 3-phase uncontrolled bridge
rectifier using power diodes / thyristors for AC to DC conversion and the drive shall
be based on IGBT technology & the VFD output shall be PWM waveform.
Rating of the Drive: The rating of the drive offered by the tender shall be suitable for
future expansion (or excel the test requirement) to load the motor for temperature
rise test and evaluating the load characteristic, no-load characteristics & lock rotor
test upto 70Hz at different frequency. The method to be followed for testing of the
motor shall be as per IEC-60349-2
5.1
Reference for Standards:
5.1.1
The design, manufacture and testing of Inverter Panels for AC Drives shall be carried
out as per the latest applicable BIS, International Standard, Indian Electricity Rules,
Code of Practices and requirement of Chief Electrical Inspectorate of the State Govt.
However, for ready reference some of the Standards are listed below.

IEEE 519 - Recommended Practice and requirement for harmonic control in
power systems.

IS 1248 - Direct acting indicating analogue electrical measuring instruments and their
accessories.

IS 1885 - Part 7 - Semi Conductor Devices

IS 1885 - Part 27 - Power Electronics

IS 3700 - Essential ratings and characteristics of semi conductor devices.

IS 6619 - Safety code for semi-conductor rectifier equipment.

IS 13947 - Low voltage switchgear and control gear.
electrical
5.2
Requirement of VFD Drive
5.2.1
Technical Requirement:
.1
Closed loop vector control (entire speed range) drive to be used with features as
specified:
The general requirement of the VFD drive is
indicative as below. In case the tenderer proposes different design for the
proposed test set up to cater to the requirement the same shall be furnished
in the offer.
a.
Speed control 0.01%, dynamic 0.2%sec, torque lin. <2%, torque rise time ~2
ms.
b.
Starting Torque: 150 %, Frequency stability: +0.1%.
c.
Overload: 110% load for 60 seconds. Once in every 10 minutes.
d.
The ratio of peak inverse voltage to peak voltage of the drive shall be more
than 2.5 (under normal operating conditions).
e.
Drive Design temperature: 45 ºC.
f.
Speed range: 1 % to 270% of the normal speed of the motor.
.2
AC Output: Current waveform should be approx. sinusoidal to provide step less
speed variation for the operation of traction motors.
.3
AC drives should be designed / supplied for an output frequency range of 1Hz to
160Hz.
.4
The efficiency of the drive at rated voltage and load should not be less than 97.5%.
.5
The drive supplied should be with input reactor for reduced harmonics as per
IEEE159. VFD module and the input reactor should be of same make.
.6
The Bidder shall provide Type and expected life of DC link capacitors used in the
system.
5.2.2
General Requirement
.1
The output current of the drive shall be sized on the basis of full load current of
motor. It may need to be oversized to accommodate application requirements such
as high starting, overload or accelerating torque. It shall also be able to accelerate
the load from zero to full speed under specified voltage and frequency variation.
.2
The Drive shall be based on Microprocessor based Digital controller with digital &
analogue input / output cards to fulfil the controlling of system.
.3
Auxiliary power supply: 415V AC, 3-phase, 50 Hz supply shall feed Control
transformer, panel cooling, motor cooling, panel illumination, panel and motor space
heaters etc. Suitable switchgear ( Fuse unit or MCCB) shall be provided for isolation.
.4
Control supply :Control supply voltage shall be considered 110V / 220V AC. All logic
control wiring, indication lamps, control contactors, Local control station wiring, and
discrete DCS I/O shall be at Control supply voltage.
.5
Drive should be suitable for Switching Duty of 5 starts per hr in normal operation and
6 starts per hr in trial run.
.6
Acceleration and de-acceleration time: Up to 3000 seconds independently
adjustable.
.7
All the drives should be with varnished PCBs. Operator Display & control for
parameterization of drive to be provided on panel door.
.8
Open Circuit mode: The drive shall be operational in open circuit mode i.e.
disconnected from the motor for start-up adjustments and troubleshooting.
5.3
Operation features of the drive: The drive shall have the following features as
mention below:
.1
Soft start with adjustable time acceleration.
.2
Speed reversal locking for unintended direction of rotation.
.3
User programmable carrier frequency for optimum harmonic distortion and switching
losses.
.4
Auto tuning feature to configure Drive parameters according to Motor rating and
characteristics.
.5
Operator display unit shall be multi-line alphanumeric keypad for on line simple
English text message for cause of fault, fault diagnostics, parameterisation,
configuration, and control. It shall store History of last 30 faults with real time stamp
and actual value recorded at the time of fault. The operator display unit shall display
the cause of fault in English text message not in code, so that fault can be identified
& resolved to reduce the down time of system.
.6
Power loss ride thru – in case of momentary supply failure, the drive shall be able to
run load by using kinetic energy of rotating motor.
.7
Flux optimisation – to reduce energy consumption and reduce motor noise level
when motor running at below nominal load.
.8
Independently adjustable set point up and down ramps.
.10
Serial bus Communication cards with MODBUS / PROFIBUS DP Protocol to connect
with DCS.
5.4
Harmonics
.1
De-rating (if required) due to harmonic currents shall be considered to ensure rated
load without exceeding rated temperature rise under worst supply condition.
.2
Tenderer shall recommend any power de rating for the motor when operated with the
drive in order to account for the harmonic content of the drive output.
.3
Chokes and Filters: Distance of the motor with the drive can be more than 100
metres. Necessary hardware e.g. chokes / filters in load side etc. if required, shall be
supplied on the basis of calculation of peak voltages at motor terminals.
.4
Modes of operation: Panel shall be provided with 2 way selector switch for Remote /
Panel / Field (Local) mode selection. It will be possible to change the reference only
from the place of selection of operation.
.5
PC software for Configuration: A PC based, Windows 2000 / XP / NT compatible
software tool suitable for configuration, parameterisation, upload /download data,
tuning, diagnostic purpose, trouble shooting. The PC shall be connected to drive’s
RS232 / RS 485 port. Necessary hardware and complete documentation shall be
included in the scope.
5.5
Type of Protection on the Drive Panel: Following protection shall be provided on
the drive.
.1
Earth fault protection’ and ‘Surge protection’
.2
The ‘short circuit rating’ of panel should be more than available short circuit capability
of connected ac line.
.3
Capability to skip / exclude frequency bands that may cause mechanical resonance.
.4
The fault detection system shall shutdown the rectifier and inverter firing circuit and
output during fault signal. The operator display unit shall identify the abnormal
condition, which caused shut down of the drive system.
5.6
Display Indications on the Drive Panel / Operator Display

Short circuit in converter and inverter

Instantaneous over current

Breaker trip.

Thermal overload. Stall protection and Locked rotor.

I2t monitoring for power devices and motor.

Phase imbalance. Single phasing.

AC under voltage / over voltage protection.

DC link over voltage.

Control and regulated power supply failure.

High temperature protection.

Communication fault.

Transformer protection trip.

External emergency off.

Over speed / under speed.

Stator motor temperature by motor modelling.
5.7
Wiring Details of Drive:
Wiring of power cable and control cables will be laid
separately. All power cables sizing from drive to motor shall be recommended by
tenderer. All the control wiring shall be done by stranded copper wires of minimum
1.5 mm2, cross-section. All signal cables shall be 0.75 / 1 mm2 screened type. All the
wires will be ferruled at both the ends. Adequate cabling space shall be provided for
external cable termination. Inter-module wiring will be colour coded as far as
possible.
Proper wiring, shielding, grounding should be done in the panel to
minimize noise and interferences.
5.8
Bus bars Details: All metallic parts, components etc. shall be connected to main
earth bus bar. Main earth bus bar shall be connected to plant earth grid by minimum
60 x 10 mm copper bus bar. Bus bars should be of Electrolytic grade copper or
aluminium type. It should be suitably supported to avoid stress on the terminals.
Support points shall not be used for power tapping.
5.9
Wherever required, Live parts shall be suitably shrouded with transparent acrylic
sheets.
5.10
Terminal Board Details: All external power and control circuit connections shall be
brought on readily accessible spring press screw less connectors at the bottom of the
cubicle. Ample space shall be provided at the bottom up to a height at least 250 mm
for connecting the Power & Control Cables and for easy accessibility.
5.11
Each functional module should have its own terminal board and panel should be
complete with the inter-connections between them. Terminals shall be of springpress screw less type.
5.12
All the terminating points shall be brought on the front of the Panel. The reference
voltages / signals should be displayed on digital operator station to facilitate
faultfinding. 20% extra spare terminals should be provided for customer’s interlocking
with down stream equipment.
5.13
Cooling system: The system shall be designed for continuous operation at site
ambient condition with forced cooling for drive. The arrangement shall preferably be
such that the ventilation air passes only through transistor heat sinks in a separate
duct so as to prevent dust deposition and consequent tracking.
5.14
Indications & Fault Monitoring on Control Desk Panel: The panel should be
provided with Status of the Indication Lamps - Power ON, Drive Ready, Motor
Running, Remote Breaker trip and 2 Spares. Meters should display true RMS value
of inverter drive input and output currents. All faults and running parameters like
current, speed; KW etc. shall be displayed on operator display unit on the front panel.
Following Controls switches shall be provided on the front of the panel.
5.15

A lockable mushroom head red colour push button –to operate and turn to
release type Emergency Stop PB to isolate incoming supply.

Start (green)-Stop (red) PB.

Speed raise-lower (Blue and yellow).

2-way selector switch (16 A rating) for DCS / Panel / Local mode.

Indicating meters: Meters of 96 x 96 mm Flush mounted on front panel.

AC Ammeter with selector switch on control desk panel.

AC Voltmeter with selector switch on control desk panel.
Constructional Details of the Panel:
Panel shall be floor mounted, freestanding, cubicle made of cold rolled sheet steel,
suitable for indoor (IP4X). The preferred thickness of sheet steel shall be 2 mm
except for all the covers and base plates of 1.5 mm thickness. The base channel
would be 3.0 mm thick. Panel shall have suitable lifting hooks. Louvers with filters
shall be provided on the panel doors. Drawing pockets on the doors for keeping
drawings will be provided.
All doors shall be hinged and provided with electro-mechanical interlocking so that
power cubicles can not be opened until power source is disconnected. Similarly
interlock system shall ensure that power can’t be switched on until all power cubicles
are closed.
All power and control components shall be easily accessible from panel front. If use
of rear doors are made necessary, it shall be clearly indicated in the offer.
All metal surfaces shall be painted as per RAL 7032 of DIN (Pebble Grey) before
thorough cleaning/ rinsing and degreasing of the panel All unpainted steel parts shall
be suitably treated to prevent rusting.
5.16
Type of protection of the Panel: Panel shall confirm IP42 protection. The panel
shall also have effective protection against Electromagnetic emissions. The panel
shall be totally enclosed and dust, vermin proof. Panel shall have proper separation
between HV and LV side for Human safety inside the panel.
5.17
Marking: Identification labels: All the main and sub-assemblies of the Panel shall
bear proper identification labels / tags. Information like rating, drive name, drive
number shall be inscribed on the nameplate and fixed on panel front.
6.0
Technical requirement of surface plate of Motor Test Bed: Technical requirement of
supply of commissioning of material motor test bed are as follows:

Cost iron surface plate shall be preferred to mount the traction motor for
conducting various tests.

The surface plate shall be confirms to IS: 2285-1991.

The surface plate shall be made from close grained plain cast iron conforming to
Grade FG: 220 of IS: 210-1978.

C.I. Surface Plates shall be made from one piece casting.

The finished surface plate shall have smooth machine finished for grade 3
flatness accuracies.

Flatness determination shall be done by grid method as per clause 4.3.1 of IS:
12937-1990 Indian standard on Engineering Metrology “Methods of Testing
Straightness, Flatness, and Perpendicularity”.

Flatness accuracy shall be checked by Electronic level. Computer print out of the
contour of top working surface shall be furnished.

Size of the Surface plate shall be of 2500-mmx 2500-mm in size.

Special features of grid slots for location, tapped holes, and T-slots shall be
provided on working surface to meet the dimensions of the Traction Motor.
Envelope dimension of the motor to be tested is given in Annexure-IV. It is for
reference. These envelop dimension may vary with the motors of other
manufacturers, so tenderer may have to supply necessary fixtures for fixation of
other motor having different dimensions on the surface plate.

Installation of surface plate at site is in the scope of supplier. Necessary
modifications on the civil structure for installation of the complete ‘drive system’
required for the test bed is in the scope successful tenderer.
7.0
Evaluation / Qualification Criteria of the Firm / Tenderer:
The tenderer shall be experienced in manufacturing of major equipment of the
system like VFD drive Panel and Transformer having the capability to produce
minimum 1MVA rating of these equipments. Firm / tenderer shall also be
manufacturer of motors of industrial use with a capability & exposure for combined
testing of motor & drive system together. Documentary proof for the above cited
experience shall be submitted.
8.0
QAP and Inspection Plan :
The tenderer should have a well-defined Quality Assurance Plan (QAP) for major
equipment (like VFD drive System, Transformer and switchgear) offered for
installation of the proposed test bed. He will furnish a copy of such QAP documents
along with the rating during submission of the offer. If the tenderer proposes to
obtain sub-assemblies/ components/ material from a sub-contractor, QAP
documents of sub-contractor shall also be submitted by the tenderer. The QAP shall
also include test procedure/standards and acceptance limits followed during stage
manufacturing of these major equipment. The submitted QAP will require approval of
IR. Proper test procedure for proposed system through the offered equipment
system shall also be submitted by the successful tenderer for approval by IR before
execution of the work.
9.0
Warranty:
The supplier shall offer warranty against any manufacturing
defects/commissioning noticed on the test bed or on the equipment offered for a
period of 12 months from the date of commissioning & 18 months from the date of
despatch which ever is earlier. Any inadequacies or unsatisfactory performance on
equipment due to design or manufacturing or commissioning noticed after set up of
test bed during the warranty period shall be rectified /replaced by the firm free of
cost. In such cases the warranty may be extended after modification with mutual
consent between the Firm and IR. Firm to support the system for the expected life of
atleast 5 years of the system.
10.0
Literature and Maintenance Instructions: The approved supplier shall supply
sufficient copies of manuals for operation, complete Drive maintenance and
overhaul. The approved supplier shall provide training to the personnel free of cost
with sufficient number of days at place of commissioning (i.e. DWW/PTA) till they
become expert to handle the complete drive independently for testing of the motors.
Firm should also nominate few expert to assist these personnel for testing of first 15
nos. of motors at DMW/PTA.
*********