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NAME : SUBHAMOY SINGHA ROY

REGISTRATION NO. :B1/WB/0429201/14/16

DESIGNATION : DIPLOMA HOLDER TRAINEE

( GOI/ ELECTRICAL)

TRAINING PERIOD : 02.04.2014 TO

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ACKNOWLEDGEMENT

I Express my deepest gratitude to the Vice Principle, Mr.

Sunirmal Basu For his invaluable guidance and blessings

I am very grateful to Chief Instructor, Mr. P. P. Saha for

providing us with an environment to complete our project

successfully.

I also thank all the staff member of the workshop and

technicians for their help in making project a successful

one.

Finally, I take this opportunity to extend my deep

appreciation to my family and co – trainees for all that

they meant to me during the crucial times of the

completion of my project

SL NO.

1. Brief History Of Kanchrapara Workshop

2.

SHOP NO.

Shop No.- 09 (Panel Sec.)

3.

Shop No. - 09 A

(i)Aux. Motor Sec. (ii) TM – Frame Sec. (iii) TM – Sec. (iv) TFP & GR Sec.

4.

Shop No. -

(i)Heavy Armature Section(ii)Core and Commutator Section(iii)Coil Section (iv)Transformer Section(v)ABFCR & SL (Armature Bearing and Field Coil Reclamation Section and Smoothing Reactor[SL

CONTENTS

SUBJECT

Brief History Of Kanchrapara Workshop

SHOP NO. DURATION OF TRAINING PERIOD

(Panel Sec.)

02/04/2014 to

10/08/2014

09 A

11/08/2014 to 31/12/2014

- 14

Armature Section (ii)Core and Commutator Section

(iv)Transformer Section (v)ABFCR & SL (Armature Bearing and Field Coil Reclamation Section and Smoothing Reactor[SL – 30])

01/01/2015 to 01/04/2015

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PAGE NO.

3 - 4

5 - 20

TRAINING PERIOD

11/08/2014 to 31/12/2014 21 - 54

01/01/2015 to 01/04/2015 55 - 72

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History Of Kanchrapara Railway Workshop

Kanchrapara Workshop is one of the oldest Railway workshops in the country. It was set up by the then Eastern Bengal Railway during the year 1863 at the present Loco Complex site in Kanchrapara. It was developed as an integrated shop to carry out repairs to Steam Locomotives, wooden body Carriage and Wagons. The management of the workshop was taken over by the state on 1st July, 1884. In the year 1914 a separate carriage and wagon shop was completed.

This shop has displayed high level of flexibility by adapting to the changing environment and product-mix from time to time. During the World Word II ( Since 1939 – 45) , the workshop served the Defence Department for repairs to aircrafts and manufacture of armoured cars and hand-grenade shells.

Today Kancrapara Works ranks First Indian Railway Workshop in terms of EMU

Coaches overhauled. POH Of electrical Locomotive is the major maintance and

repairing work and is the most vital activity in this workshop.

In 1962, with the introduction of 25 KV Electric traction in Eastern India, a decision was taken for remodeling Kanchrapara Workshop to make it a base workshop for Periodic Overhauling of Electric Locomotives and Electric Multiple Unit (Suburban Electric Trains) stock of Eastern and South Eastern Railways. This workshop also had the privilege of turning out the first electric locomotive after Periodic Overhauling (POH) in 1965 and the first Electric Multiple Unit motor coach was turned out after POH in the very same year.

At present Loco Complex mainly deals with repair and overhaul of Electric

Locomotives and Electric Multiple Unit Motor Coaches. The Carriage Complex

deals with Periodical Overhauling of Electric Suburban Trains, Mainline Electric

Multiple Unit trains, Diesel Electric Multiple Unit trains, Non-Air Conditioned

Coaches, Accident Relief Train vans and 8 wheeler Tower Cars.

Passenger Electic Locomotive are overhauled after the period of 6 years or 12 lack

kilometre of running which is of earliar. Reck of the Loacal EMU trains and

convenantional LOCO coaches come for POH after 18 months. The periodic

overhauling of Electric Locomotive distributed over 22 shops through out the loco

complex and 18 shop through out the Carriage complex.

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Setting up of 2.7 million litters/day Effluent Water Treatment Plant in September’ 2002 was a landmark in environmental pollution control. The workshop was accredited with ISO-9001:2000 certificate in September 2005. With up gradation of ISO-9001 certification to the latest 2008 standard recently, the workshop is geared up to meet the ever-changing requirements of Indian Railways and serve the nation with high quality output

HISTORY OF MAJOR ACTIVITY

ACTIVITY YEAR FROM YEAR TO

POH of Steam Loco 1863 1972

POH of Freight Wagon 1863 1987

POH of Conventional coaches 1863 Continuing

Manufacture of 4-Wheeler OHE

Tower Wagon

1957 1986

POH of Electric Loco 1965 Continuing

POH of Electric Multiple Unit

1968 Continuing

Rewinding of Traction Machines 1975 Continuing

POH of Diesel-Electric Multiple

Unit

2000 Continuing

POH of self-propelled ART 2003 Continuing

POH of 8-Wheeler Tower Car 2003 Continuing

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Shop No. – 9 is Apparatus Shop of Kanchrapara Railway

Workshop, Where both Periodic Overhauling (POH) and RC of Relay, meters, gauges, DJ/VCB, Pneumatic Apparatus, Compressor and Pentograph are done.

In Panel Section Has a three Section : (i) BA Panel Overhauling Section (ii) EMU Switch Group Overhauling Section. (iii) TK Panel Overhauling Section.

Mr.Subrata Dutta SSE is the Incharge of Shop No.-09 and Others SSE and JE are as follows:

Panel Section: Mr. Mahmud Alam (SSE) Mr. Amit Kr. Ghosh (JE) Mr. Bibhash Das (JE) Mr. Sushil Kumar( JE)

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BA PANEL

B.A Panel stands for "Block Apertures Panel". The BA Panel is a device by which speed of the traction motor is controlled; it’s also responsible for rotating the motor in forward or reverse direction. This section of the shop does the POH of BA Panel for both LOCO .There are tree B A panels in a loco viz. BA-1, BA-2, BA-.3. It is also called as the heart of loco. BA panel has following parts:

1. Various rating resistors. 2. Shunting Contactors:- These are used to increase the speed of the loco. These are kept in parallel with the field of the traction motor. As these contactor introduced in the circuit the field gets weakened and there by the flux reduces hence increases the speed. All shunting contactors are pneumatically controlled. This pneumatic control is done by electro valve assembly. 3. Relay QD- 1 (Differential Relay). 4. CTF-1 Inverter TR/BR or change over switch: - These are two electro valves assembly for CTF-1, one for TR (traction) side operation and another for BR (Breaking) side operation. 5. J-1 (Reverser):- The electro valve assembly for J-1 reverser one for forward direction (-->) operation of J-1 and another for reverse direction (<---) side operation of J-1.

BA-2 and BA-3 contains the following accessories:-

1. Field weakening resistance. 2. 2 Line contactor-All are pneumatically controlled. 3. Shunting contactor. 4. CTF-2(BA-2), CTF-3(BA-3). 5. J-2 reverser. 6. QD-2: Differential relay for slipping. 7. Q-20: Relay o/p voltage.

Short Description of BA Panel Parts :- Line Contactor :

These Contactors are used for forming the circuit of the Traction Motors. Line Contactors L1 to L6 are used to connect the motors in circuits. These Contactors are designed to open at off load. Auxiliary inter locks are provided to the Contactors, wherever necessary. These interlocks ensure the sequence of operations in the different circuits. There are six line contactors L1 to L6 to give path to TMs 1 to 6 respectively. These line contactors are controlled by switches HMCS-1, HMCS-2, HVSI-1, HVSI-2, HVMT-1 & HVMT-2. Drum Contactor (J1 & J2, Reverser Switch and CTF – 1 or CTF – 2 or CTF – 3 , Traction

Commutator Switch ) :- Drum contactor is closed and opened with the rotation of a Drum. The Drum is made up of an insulated material. The movable contact is in the form of copper segment, which is fitted on the drum. These contactors are always operated on no-load, hence arc-chutes are not required. The reversers J1& J2 provided in Loco are Drum contactors. From CAB 1 leading direction, the manual operating handles of both J1& J2 should be upward. When MPJ is moved to ‘F’ position from ‘O‘ position. When MPJ is moved to ‘ R ‘ from ‘ O ‘, both the reverser J1& J2 should be thrown to downward direction and the CAB2 is in the leading direction. Mainly for change the direction of rotation of Traction motor The CTF 1, 2, Drum Contactors are having

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two positions (i) Motoring or Traction, (ii) Braking When MP is on motoring side, the CTFs are thrown upwards and when MP is on Braking side, the CTFs are thrown downwards. For ensuring the position of operation, manual operating handle is also provided CAM CONTACTOR :-

Cam contactor is opened or closed by the position of cam with movable contact. The cam contactors can be operated by SMGR or manually with a handle. While progression or regression of notches any of 3 CGRs should be closed to avoid intermittent supply. So, minimum one CGR should be in close position at any notch. When the roller is in the cavity, the movable jaw gets lowered and CGR gets opened. When the roller is on projected surface of the cam, the CGR gets closed as the movable jaw lifts up. By means of an auxiliary contact [cam contact] the GR position is indicated in Loco Pilot’s Desk by pilot lamps. Heavy ARC-CHUTES are provided with locking clips on either sides, as heavy arcs are formed while opening the CGRs. TFPs gets supply from TFWR through CGRs. CGR 12&3 are located in HT2 compartment. To arrange different type of power circuit during breaking mode.

Six (6) “T” Shape Segment, Two(2) “T” Shape Segment + Three(3) “C” Shape Segment and six (6) “C” Shape Segment Shunting Contactor : All Contactor either 9 Shunting Contactor or 12 Shunting Contactor

Rated Voltage = 1270 V DC Rated Current = 125 A DC Rated Air pressure = 7kg/cm² Rated Aux. Coil Voltage = 110V DC Electro Pneumatic Contactor is use

It weak the motor field coil, increase the speed of the motor. Generally Shunting contactor is use where low level to high level load is use or wagon is use.

Breaking Excitation Extractor(C – 145) : - Rated Voltage = 75V AC Rated current = 850 AC, 50 Hz Rated Air Pressure = 7Kg/cm² Rated Aux. & Coil Voltage = 110V DC

Relay Q50 : -

This is main control relay, which is suitable in relay board. This relay supervise of following equipments Revrerser J₁ and J₂ CTF – 1, CTF – 2, or CTF – 3 C – 145 Rated Current = 1000 A DC Rated Voltage = 1500 A DC or 1270 V DC Electro Valve Rating (MTDJ) :- Rated Voltage : 110V Air Pressure : 8 kg/cm²

Fig : BA Panel ( Model No.

Work Instructions For Overhauling Of BA Panel Of Conventional Electric Locomotives SCOPE :- Work instruction for overhauling of BA

POH/RC RESPONSIBILITY:- SSE/PANEL Section of SHOP PROCEDURE :- Overhauling of BA INCOMING CHECKING & STRIPPING OF BA1/BA1+4 PANEL

(i) Open the arc chute of all EP Contactors from the Panel.(ii) Open Electrical Connection of Magnetic coils of EP Contactors, Reverser and CTF and

their Inter Lock Contacts also(iii) Open Pneumatic Connection of EP Contactors, CTF and Reverser.(iv) Open fixation bolts of EP Contactors ( Shunting are line also in some cases). Rev

and CTF and dismount from panel by crane with sling and put them on work bench.(v) Open all power circuit bus bar connection, including RS Connection, LTBT/LTSB all

connection of control cable in POH work. In case of POH+RC work, cut all the control cables at LTBT connection ends. Collect the stripped material and keep it in custody room.

(vi) Open the foundation bolts of LTBT, LM fitting, PCLCrate from panel by crane with sling and put them on the work bench.

(vii) Cut the old benching tapes and remove control aux. cable and old glass tape from all Stiffeners.

(viii) Necessary repair to be made of panel frame including stiffeners also by welding or otherwise etc. if any damage.

CLEANING & ATTENTION OF STRIPPED MATERIALS

(i) Clean The Panel frame with Stiffeners and foundation Porcelain insulator of RS create as well as RS element with K. Oil, nylon brush, wire brush and cotton waste.

Fig : BA Panel ( Model No. –L/27787- BA₂)

Work Instructions For Overhauling Of BA Panel Of Conventional Electric LocomotivesWork instruction for overhauling of BA-1, BA-4, BA-2 & BA-3 Panel During POH &

SSE/PANEL Section of SHOP-9/KPA Overhauling of BA-1 & BA-4Panel During POH/POH+RC of LOCO

INCOMING CHECKING & STRIPPING OF BA1/BA1+4 PANEL :- Open the arc chute of all EP Contactors from the Panel.

en Electrical Connection of Magnetic coils of EP Contactors, Reverser and CTF and their Inter Lock Contacts also Open Pneumatic Connection of EP Contactors, CTF and Reverser. Open fixation bolts of EP Contactors ( Shunting are line also in some cases). Revand CTF and dismount from panel by crane with sling and put them on work bench.Open all power circuit bus bar connection, including RS Connection, LTBT/LTSB all connection of control cable in POH work. In case of POH+RC work, cut all the control

les at LTBT connection ends. Collect the stripped material and keep it in custody

Open the foundation bolts of LTBT, LM fitting, PCL-X-Socket, SHAACrate from panel by crane with sling and put them on the work bench.

ng tapes and remove control aux. cable and old glass tape from all

Necessary repair to be made of panel frame including stiffeners also by welding or otherwise etc. if any damage.

CLEANING & ATTENTION OF STRIPPED MATERIALS :- rame with Stiffeners and foundation Porcelain insulator of RS create as

well as RS element with K. Oil, nylon brush, wire brush and cotton waste.

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Work Instructions For Overhauling Of BA Panel Of Conventional Electric Locomotives : Panel During POH &

4Panel During POH/POH+RC of LOCO

en Electrical Connection of Magnetic coils of EP Contactors, Reverser and CTF and

Open fixation bolts of EP Contactors ( Shunting are line also in some cases). Reverser and CTF and dismount from panel by crane with sling and put them on work bench. Open all power circuit bus bar connection, including RS Connection, LTBT/LTSB all connection of control cable in POH work. In case of POH+RC work, cut all the control

les at LTBT connection ends. Collect the stripped material and keep it in custody

Socket, SHAA-1 Shunt and RS Crate from panel by crane with sling and put them on the work bench.

ng tapes and remove control aux. cable and old glass tape from all

Necessary repair to be made of panel frame including stiffeners also by welding or

rame with Stiffeners and foundation Porcelain insulator of RS create as well as RS element with K. Oil, nylon brush, wire brush and cotton waste.

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(ii) Clean the control cables, in case of POH only HTSB/HTBT ( after unscrewing the HT terminal bolts to open HT separators) LTBT SHAA-1 Shunt, HT Terminal Bolt, HT separators etc. with K. Oil & then by petrol and soft nylon brush along with cotton waste.

(iii) After drying the natural air, apply paint on Panel frame, RS frame, air pipe line etc. (iv) Clean Copper bus bar ends with steel wool/emery Paper and then do necessary tinning.

(v) Apply anti-track red varnish on all stiffeners , cupper bus bars except tinning portion, HTBT, contractor fixing insulated bar etc.

(vi) Prepare and replace all the control cables in case of RC work and change practically/ fully these cables on condition basis in case of POH work.

(vii) Provide nomex paper in gap of EP Contactor fixation clamp. (viii) Blow air pipe with compressed air in order to clean out any dust Particle if available. (ix) Check IR value of insulated support tube/ Base.

ASSEMBLING OF MATERIAL :-

(i) Assembling LTSB/LTBTs with proper order of number and HTSB/HTBT along with terminal bolt and HT separator.

(ii) Fit all LTSBs, HTSBs, PCLX Socket, SHAA-1 Shunt, LM fittings etc. in the Panel. (iii) Make LTSB connection of control cables in proper route as incoming in POH Work. (iv) In case of RC work, make new LT cables with lagging, numbering, layout with

proper route as per CLW’s cabling chart in the panel. (v) Do control cable connection of all the components such as PCLX Socket, SHAA-1, LM

fitting holder etc. (vi) Lift reverser & CTF (after overhauling & Testing) and then RS create also by crane with

sling from work bench and place on the Panel and mount. Fit/mount overhauled all EP connectors on the Panel.

(vii) Make all LT control cable connection at the contactors and reverser/CTF interlock ends and all the magnet coil also. Ensure fitting of interlock cover in case of Reverser/CTF.

(viii) Make Pneumatic connection of all EP Contactors, reverser and CTF where applicable. (ix) Check IR valve of contactor fixing insulated support tube and flylane HTSB with megger. (x) Make all the HT Bus bar connection at the both ends in the panel. (xi) Fit all the Chute of EP Contactors in the Panel.

TESTING OF PANEL :-

(i) Connect air Pressure to air Pipeline and Check the air Leakage with Soap Water. (ii) Check cable continuity from SB ends to other ends. Give 110V DC Supply to LTSB and

also check Operation manually. (iii) Check RS element valve with micro-ohms meter and also IR valve with megger. (iv) Offer for inspection and attend booking, if any. (v) Write name plate, apparatus number and also LOCO number with paint. (vi) Record all the best result in the Check Sheet. (vii) Hand Over BA-1 & BA-4Panel to Shop no-11 for equipping.

OVER INSTRUCTION FOR OVERHAULING OF BA-2 & BA-3 PANEL DURING POH/POH + RC

OF LOCO :- (i) Open the arc chute of all EP contactors from panel frame. (ii) Open Electrical Connection of magnetic coils of EP contactors, reverser, and CTF and

their interlock contacts also. (iii) Open pneumatic connection of EP contactors. CTF and reverser. (iv) Open Foundation bolt of EP Contactors ( Shunting, line & C 145 also in some cases) and

CTFs and reverser dismount from panel by crane with sling and put hem on work bench.

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(v) Open all the power circuit bus bar connection including RS connection, LTBT/ LTSB all connection of control cable in POH work. In case of POH + RC work, Cut all the control cables at LTBT connection ends. Collect and put bus bars in custody rooms.

(vi) Open the foundation bolts of LTBT, LM fitting, PCLX socket, SHF 1+2, SHAA-2, HQOP 1+2, RQOP 1+2, RQ-20 and RS crate from panel by crane with sling and put them on the work bench except RQOP 1+2 and RQ20.

(vii) Hand over RQOP 1+2 & RQ20 to relay Section. (viii) Open the Electrical connection ( Both LT & HT) of C118 contactor along with surge trap

unit While Fitted in BA 2+3 panel in some LOCOs. Hand over C118 contactor to EM contactor panel section & surge trap unit to Misc. section. ( All relay are to be collected by relay section)

(ix) Cut the old bunching tape and remove control auxiliary cables and old glass tape from all stiffeners.

(x) Necessary repair to be made of panel frame including stiffeners also. CLEANING AND ATTENTION OF STRIPPED MATERIALS :-

(i) Clean the panel frame & porcelain foundation insulator of RS crate as well as RS elements with K.oil, nylon, wire brush and cotton waste.

(ii) Clean all the control cables in case of POH only, HTSB/HTBT ( after unscrewing the HT terminal bolt to open HT Separators) LTBT, SHAA-2 Shunt, HT terminals bolt, HT Separators, HQOP 1 + 2, SHF 1 + 2 etc. with K. Oil and then Petrol and soft nylon brush along with cotton waste.

(iii) Apply paint on panel frame, RS frame air pipe line etc. after drying with natural air. (iv) Clean copper bus bar ends with steel wool, emery paper and then do necessary tinning. (v) Apply red anti track varnish on all stiffeners copper bus bars except tinning portion,

HTBT, Contactor fixing insulated bar etc. (vi) Prepare and replace all the control cables in case of RC work and change fully/Practically

on condition basis in case of POH work. (vii) Provide nomex paper in gap of EP contactor fixation clamp. (viii) Blow the air pipe with compressed air of 8kg/cm sq. in order to clean out any dust

particle, if available. (ix) Check IR value of insulated support tube/bar.

ASSEMBLING OF MATERIALS :- (i) Assemble of LTSB/LTBT with proper order of numbers and HTSB/HTBT along with

terminal bolts and HT separator. (ii) Fit all LTSBs, HTSBs,PCLX Socket, SHAA-2 LM fitting, HQAP 1 + 2 switches RQOP 1 + 2 &

RQ- 20 (both coming from relay section ) etc in the panel. (iii) Make LTSB Connection of control cables in proper route as incoming in POH work. In

case of RC work, make new LT cables with lagging, numbering, sleeving and layout with proper route as per CLW’s cabling chart in the Panel.

(iv) Do control cables connection of all components such as PCLX socket, SHAA-2, LM fitting Holder, HQOP 1 + 2, RQOP 1+2, RQ – 20 etc.

(v) Lift reverser/ CTF and then RS crate also by crane with sling from work bench and place on the panel and mount. Fit/ mount over haulted all EP contactors on the Panel.

(vi) Make all the LT control cable connection at the contactors and reverser/CTF interlock end and all magnet coils also. Ensure fitting of inter lock over in case of reverser/CTF.

(vii) Make Pneumatic connection of all EP contactors, reverser and CTF where applicable.

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(viii) Mount C-118 contactor (Coming from EM contactor panel section) along with RC surge trap unit on the panel in case of incoming available and make the necessary LT and HT connection.

(ix) Check IR value of conductor fixing insulated support tube and nylon HTSB with megger. (x) If any defects found in above apparatus replace by new. (xi) Make all the HT bus bar connection at the both ends in the panel. (xii) Fit all the arc chute of EP contactors in the Panel.

TESTING OF PANEL :- (i) Connect 8kg/cm. sq. air pressure to air pipeline and check the air leakage with soap

water. (ii) Check cable continuity from SB end to other and give 110V DC Supply to LTSB and Check

Operation manually. (iii) Check RS element value with micro ohm. Meter and also IR value with megger. (iv) Offer for inspection and attend booking, if any. (v) Record all test result in the check sheet. (vi) Write name plate, apparatus number and LOCO number with Paint. (vii) Hand Over ready BA2/ BA2+3 Panels to shop no.-11.

WORK INSTRUCTION FOR OVERHAULING OF EP CONDUCTOR : INCOMING CHECKING AND DISMANTLING :

(i) Visual Check of defects, deficiency of components/ Parts, if any. (ii) Visual Check of damage & deformation, if any. (iii) Put EP Conductor (Line, C 145 and Shunting) on the work bench manually. (iv) Do dusting of EP conductor with soft nylon brush, duster or clean dry compressed air. (v) Open the fixation screws of the servomotor assembly and moving contact assembly

from the conductor. (vi) Dismantle of side plates, blowout coil assembly servo assembly, moving contact

assembly and both fixed & moving contacts. CLEANING, OVERHAULING AND ASSEMBLING :-

(i) Clean the dismantled side plates by K. Oil and then Petrol. Remove any frames of metallization with sand paper. Replace them if found split or scratched.

(ii) Check the blowout coil with brush or dry comp. air. (iii) Check the condition of asbestos thread provided to avoid its inter turn short circuit. (iv) Change it on condition basis. (v) Clean the contact portion of blow out coil by Polish paper and with petrol if any

overhauling works. (vi) Varnish the coil with red insulating varnish. (vii) Remove the EP valve by unscrewing bolts fitted on Servomotor. (viii) Clean the exciting grease of piston, piston cap, cylinder and spring with duster. Wash

them with petrol. (ix) After drying, replace new piston bucket, lubrication felt and all gaskets. (x) Reassemble the servomotor assembly with cylinder & new EP valve and then lubricate

with mobile oil. (xi) Remove the knuckle spring from moving contact assembly and check roller, roller arm,

brush, roller pin, axl pin and spring etc. for any defect change if required. (xii) Clean roller arm, brass plate and moving contact lever.

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(xiii) Check the condition of all flexible shunt. If found any abnormality such as breakage of shunts then replace by new moving contact assemble/ new contactor.

(xiv) Lubricate the roller & brush. Open moving contact and clean the contact portion of assembly by polish paper and then refit by new one.

(xv) Refit the knuckling spring. (xvi) Refit the fixed contact by new on fixed contact/ blow out coil assembly in the fitment of

both the contactors; air gap between contacts and contact holder is not permissible. (xvii) Finally, assemble the EP contactor fitted with side plates, blow out coil assembly

moving contact assembly and servomotor assembly along with new insulating sleeves/ components including distance piece especially damage in case of line/ C 145 contactors.

(xviii) Lubricate all moving parts. TESTING OF EP CONTACTOR :-

(i) Mount the overhauled contactor on the test bench manually; Connect its nipple with

compressed air supply ( maintain from 5 to 9 kg/cm sq.) (ii) Check the coil resistance, min. operating air pressure, min. working voltage, pick up and

voltage, air tightness test, IR value between coil & Body of EP ( NC4 ) Value. (iii) Check air tightness test of contactor in coil energize and de-energize Condition. (iv) Ensure that there is a no gap between fixed and moving contact while closing. (v) Ensure that contact bedding between fixed and moving contact is more than 80%, Check

and adjust main contact gap with “ GO – NOT GO ” gauge in open condition. (vi) Check main contact pressure with the help of spring balance. (vii) Check continuity and discontinuity of aux. interlock. (viii) Check Mechanical endurance test for 20 times continuous operation in order to

maintain air pressure range of 5 kg to 9 kg/cm sq and voltage range of 68 volts to 136 volts/cm sq.

(ix) Check the locking condition of arc Chutes. (x) Check IR value with meggar (a) Between power terminal & earth with arc Chute. (b) Between power contact to contact with arc chute fitted and contact in open condition. (xi) Record all results of Test Parameters in the Check sheet.

WORK INSTRUCTION FOR OVERHAULTING OF RESERVER (J) AND TRACTION BREAKING

SWITCH (CTF)

INCOMING CHECKING & DISMANTLING:-

(i) Visual Check of defect, deficiency of components/Parts of frame & base of Switch, if any. (ii) Visual check of damage & deformation, if any. (iii) Put reverser/CTF on the work bench manually. (iv) Remove finger contact assembly, servomotor, auxiliary switch assembly, pressure

setting nut & spring, Aux. interlock cover etc. from reverser/CTF. (v) Remove mobile drum contacts from drum assembly by unscrewing allen screw, NC – 4

EP valve from servomotor, finger contact from foundation base and cylinder cap of servo motor with piston.

CLEANING, OVERHAULTING AND ASSEMBLING:-

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(i) Clean, dismantled parts/ components such as frames, finger contact assembly, dram contact, insulated dram etc. with blowing of compressor air and then with K/Oil and finally with petrol.

(ii) Remove the EP valve by unscrewing bolts fitted on servomotor; clean the existing grease of servomotor assembly.(Piston, Piston Cap, Cylinder and Spring ) with duster, wash them with K.Oil and then Petrol.

(iii) Reassemble the servomotor assembly. With new replacement of EP valve, lubricant the servomotor with mobile oil.

(iv) wash the drum including bearing with petrol. Apply a coat of red varnish on the insulated parts of the drum and finger contact fixing bar ( insulated carrier ).

(v) Check “ U ” for the roller and replace the roller if worn out. (vi) Adjust the driving cam so that the interlocking lever should rest in cam group, when the

servomotor piston reaches its max. limit. (vii) Remove any groove and scratch mark form both drum segment contact finger contact

by an extra smooth file and fine sand paper after unscrewing both the contacts.

(viii) Replace both the contact when these wear by 1 mm. from the original thickness ( approx 2 mm. ) of silver lining and any breakage of flexible shunt in case of finger contacts assly.

(ix) Check the dip ( Clearance between finger contact & contacts holder of finger contact assly., which should be 2 + 0.5 mm).

(x) Replace all aux. contacts by new. (xi) After painting of frame assemble the reverser/CTF with ensuring double doewel pins at

all places. TESTING OF REVERSER & CTF :- (i) Mount the overhauled reverser/CTF on the test bench and connect its nipple with

compressed air supply ( maintain from 5 to 9 kg/cm sq. ) (ii) Check the coil resistance, minimum operating air pressure, min. working voltage, pick up

& drop out voltage, air tightness test, IR value between coil and body of EP ( NC 4 ) valve (iii) Check air lightness test of reverser/ & CTF in coil energized and de- energised condition. (iv) Ensure that there is no gap between fixed and moving contact. Check the dip clearance

of finger contact. Also Check main contact pressure. (v) Check the continuity & discontinuity of aux. interlock. (vi) Check the mechanical endurance for 20 times no load conditions operation by

energizing electro valve from 68V to 100V DC supply and maintaining air pressure from 5 kg/cm sq. to 9 kg/ cm sq. The switch should not shown any sluggishness or abnormality.

(vii) Check the minimum air pressure, which should be 3kg/cm sq. (viii) Check the IR value with meggar. (ix) Between power terminal and earth. (x) Between two terminals of finger contacts as well as drum contacts also. Record all test

parameters in the check sheet. In EMU the BA Panel is know as switch group(1,2) and consists of the following parts:- SWITCH GROUP 1 :- 1. Electro-pneumatic motor Contractor(M1,M2) 2. Electro-pneumatic Reverser(1) 3. Negative Electro-pneumatic Contractors(NC1,NC2) 4. Overload Relay(1,2) 5. Current Limiting Relay Board(CLR,2 relays)

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6. Notch Repeater Relay(NR,1,2)

7. Auxiliary Over voltage Relay(AOVR) Switch Group 2:- 1. Electro-pneumatic motor Contractor (M3, M4) 2. Electro-pneumatic Reverser(1) 3. Negative Electro-pneumatic Contractors(NC3,NC4) 4. Overload Relay(1,2) 5. Current Limiting Relay Board(CLR,2 relays) 6. Auxiliary Over voltage Relay(AOVR)

CHECKING & TESTING AFTER OVERHAULING :-

TESTING DATA

M/CONTACTOR [M₁-M₄, NC₁-NC₄]

5022 PC6 1500V , 375A NR₁ NR₂

REVERSER (K₁, K₂) 29RPS 1500V, 600A

Lc CONTACTOR, 8EC4,150V

12A(LH), 100 (RH)

Vc CONTACTOR 8EC5,1500V

12A(LH), 12A(RH)

Cc, CONTACTOR 19EC, 150V

200A

Cc2 CONTACTOR SEC, 120V, 10A

WORKING AIR PRESSURE (kg/cm²)

4.9

-

- - - -

MAIN CONTACT GAP (mm)

20.6 TO 23.8 (M₁ - M₄/

NC₁ - NC₄ )

19.05 ± 1.6

10.3(MINᴹ) 10.3(MINᴹ) 10.3(MINᴹ)

6.15 TO 7.35

AUX. CONTACT GAP (mm)

2.4 TO 3.2

28.6 (MIN)

-

-

- -

MAIN CONT. PRESSURE (kg)

1.8 TO 3.0 (M₁ - M₄/NC₁ - NC₄ )

1.59 (NR₁ - NR₂)

2.3 – 3.6 kg (O/C)

2.49 – 4.1 kg (I/C)

0.9 TO 1.8 0.9 TO 1.8 2.3 TO 3.2

0.10 TO 0.15

AUX. CONTACT PRESSURE (kg)

0.11 TO 01.17 0.34 - - - -

VALVE FERRULE BORE (mm)

2.38 (M₁ - M₄/NC₁ - NC₄ )

1.59 (NR₁ - NR₂)

6.35 - - - -

AIR BOLT BORE (mm)

6.35 (M₁ - M₄/NC₁ - NC₄ )

130 (NR₁) 2.38 ( NR₂)

- - - - -

COIL RESISTANCE AT 20˚C 957 ± 8% dc 919 ± 8%

102 + 8% (SET COIL)

105 +8% (TRIP COIL)

102 +8% (SET COIL)

105+8% (SET

COIL)

468 +8% 1122+8%

COIL PICK UP VOLTAGE 55V (min) 55V DC (MIN)

55Vdc min 55Vdc min 55Vdc min 55Vdc min

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COIL DROP OUT VOLTAGE

CAM TO ROLLER GAP (min)

10V dc 10v

dc(min)

Megger Value :-

(i) Body To Magnet Coil O/C – OUT SIDE CONTACT (ii) Body To Fixed Contact 5MΩ I/C – IN SIDE CONTACT

(iii) Body To Mobile Contact (iv) Body To Terminal Board

BLOCK DIAGRAM OF SWITCH GROUP FOR EMU :

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Motor Contactor = 4 Nos. Magnetic Contactor = 4 Nos. Reverser = 2 Nos. NR₁ Notching Relay =1 Nos. NR₂ Notching Relay = 1 Nos. O/L Over Load = 4 Nos. Current Balancing Relay = 2 Nos. Over Voltage Relay = 1 Nos. Aux. Voltage Relay = 1 Nos.

TK PANEL

TK Panel is the another main part of LOCO. TK Panel also call AC2 Panel. Its play vital role in Panel, All cable and connection go through in this section. In this section divided into many parts, like (i) Relays, (ii) Resistance, (iii) Diodes, (iv) Electro Pneumatic Contactor (3 Phase), (v) Switch board, (vi) BD, (vii) Microprocessor, (viii) Capacitor for MCP and ARNO, (ix) LTBA Checking & Testing after overhauling/ EM Section : During Overhauling and RC all contactors are maintain the following chart.

Test C101, C102, C103, C105, C106,

C107, C111, C121, CPR C118

1.Main Contact Gap 8.5 ± 1 mm 17 ± 1 mm

2.Aux. Contact Gap 6 ± 1 mm 6 ± 1 mm

3.Main Contact Pressure 850gm – 1050gm 5 – 6.7 kg

4.Aux. Contact Pressure 80gm ± 10% 80gm ± 10%

5.Crussing 3.3 – 4.3 mm 4.45 – 4.55

mm

6.Magnet Coil Resistance Value 585 ± 5% Ω 95Ω ± 5%

7.Min Pick Up Voltage 68 V 68 v

8.Drop Out Voltage 10 – 20v 10 – 20 V

9.Dist. b/w Pole to Pole(3 Phase) 40mm -

10.Dist b/w Yoke & Armature 12mm 12mm

11.Allowable Slackness (a) Diameterically

(b) Laterally

0.5mm

0.2 to 0.5mm

0.5mm

0.2 to 0.5mm

12.Phase Sequence

13.Megger Valve with 500v Meggar (a) B/w pole to pole (b) B/w Pole to Body (c) B/w Coil to Body

5MΩ 5MΩ 1MΩ

5MΩ 5MΩ 1MΩ

14. Verify the Alignment of Main Moving Contacts with respect of fixed contacts

RELAY :-

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Relay is an electrical device and also an electrically operated switch placed in between the main electrical power circuit and the circuit breaker in such a manner that any fault in the circuit actuates the relay which in turn energises the trip circuit and causes circuit breaker to open and turns protects the circuit from any severe damage.

When an electric current is passed through the coil it generates a magnetic field that activates the armature, and the consequent movement of the movable contact(s) either makes or breaks (depending upon construction) a connection with a fixed contact. If the set of contacts was closed when the relay was de-energized, then the movement opens the contacts and breaks the connection. When the current to the coil is switched off, the armature is returned by a force, approximately half as strong as the magnetic force, to its relaxed position. Usually this force is provided by a spring. In a low-voltage application this reduces noise; in a high voltage or current application it reduces arcing.

When the coil is energized with direct current, a diode is often placed across the coil to dissipate the energy from the collapsing magnetic field at deactivation. Alternatively, a contact protection network consisting of a capacitor and resistor in series may absorb the surge. Notching Relay :

A DC motor power circuit relay which detects the rise and fall of current in the circuit and inhibits the operation of the resistance contactors during the acceleration sequence of automatically controlled motors. The relay operates a contactor stepping circuit so that, during acceleration of the motor, when the current falls, the relay detects the fall and calls for the next step of resistance to be switched out of the circuit. See DC Resistance Control and Camshaft. No-Volt Relay :

A power circuit relay which detected if power was lost for any reason and made sure that the control sequence was returned to the starting point before power could be re-applied. See Motor Protection. Overload Relay :

A power circuit relay which detected excessive current in the circuit and switched off the power to avoid damage to the motors. See Motor Protection above. RELAY POSITION FRONT SIDE FOR CONVENSATIONAL LOCO :

TK Panel having the following Relay : QOP – 1 & QOP – 2 = Earth Fault Relay for Circuit for Power circuit to Earth Protection QOA = Earth fault relay for auxiliary circuit. QE = Overload Relay For Breaking Excitation. QRS - 1.1 & QRS - 1.2 = Overload relay for rectifier protection. Q – 30 = No Voltage relay. QLM = Overload relay for main Transformer. QLA = For tripping purpose in Auxiliary. Microprocessor Relay With SIV

RESISTANCE : The electrical resistance of an electrical conductor is the opposition to the passage of an electric current through that conductor. The inverse quantity is electrical conductance, the ease with which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical notion of friction. The SI unit of electrical resistance is the ohm (Ω).

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In TK Panel there are seven (7) nos. resistance, there are as follows – RQOA1 RQOA2 RHOBA RPQOA RPQOP1 RPQOP2 RQ3O (680Ω) (680Ω) (210Ω) (150Ω) (150Ω) (150Ω) (Value Variable) In RQOA1, RQOA2, RHOBA and RPQOA No Need For SIV. RQ3O No Need For Microprocessor. DIODES USE IN TK PANEL ( Microprocessor With SIV) :

CT & SIGNAL CONDITIONING UNIT:

Electromagnetic Contactor each parts consist of the following main parts :

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1. Yoke 2. Armature 3. Coil 4. Fixed Contact 5. Auxiliary Contacts 6. Arc Chutes 7. Pressure Adjusting Springs 8. Copper Shunts 9. Bearing 10. Bolts, Nuts, Screws, Washers

CONSTRUCTION : These Contactors have a U – Shaped fixed part (yoke), a fixed core and a U- Shaped moving armature. The armature is attracted inside fixed yoke. The auxiliary contacts are fitted below the magnetic circuit. Dimensions of contactor type CBC – 45 – A – 320Z are shown. MAGNETIC COIL CHARACTERISTICS: (a) RESISTANCE : Coil resistance should be 580 ± 8% ohms at 20˚c. (b) OPERATING (PICK UP) VOLTAGE: The minimum operating voltage should not be more than 57 V at ambient temperature when the contactor picks up. (c) RELEASING ( DROP OUT) VOLTAGE : The voltage at which the contactor electrically opens out should be more than 10 V and less than 20 V at ambient temperature.

IMPORTANT PARAMETERS OF ELECTRO MAGNETIC CONTACTOR TYPE I EMC/ 1 : 1968 : 64A : 3P

Main Circuit rated voltage : 500 V AC, 50HZ Main Circuit rated current : 80 A, AC 95 A, AC for high Capacity Contactor Minimum Pick up voltage : 57 V D.C. Rating of operating coil Resistance at 20˚c : 580 ± 8 % ohms Nominal Voltage : 110V D.C. Operating Voltage : Between 68V to 136 V DC Number of Auxiliary Contacts : 2 N/C and 2 N/O Rated Voltage of auxiliary contacts :136 V D.C. Rated current of auxiliary contacts : 5 A D.C. Rupturing capacity of auxiliary contacts : 2A, 136V DC at L/R Ratio of 25/1000

ELECTRO MAGNETIC CONTACTOR :-

This is a 3Phase,380V, AC, 50 Hz contactor with 3 Poles and is used for operating auxiliary machines in the locomotives, Operating Coil is Connected to 110V DC by switching “ON” the lever of BL key from driver desk. When coil get energised its armature is attracted then the fixed and moving contacts get closed. According the auxiliary machines starts with their respective time delay.

THE FOLLOWING CONTACTORS ARE USED IN THE LOCOMOTIVE :-

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SL. NO.

Description Abbreviations

1. Contactors for Traction Motor Blower

Motors C105, C106, MVMT₁, MVMT₂

2. Contactors For Main Compressor Motor C101, C102, C103

3. Contactors for Transformer Oil Cooler

Blower Motors C107 HVRH

Switch Board :

LECC ( Lamp/ Fuse Tester) ZUBA ( Voltmeter Relaxation Switch) HSIV (Static Inverter) HBA ( Battery On Off Switch) HPH ( Oil Pump Rotary Switch) HVRH ( HVRH Motor) HCP( Compressor Motor Snt. MCP) HVSL 2 ( Silicon Rectifier Motor)

HAD ( Air drier switch) HPAR ( Head Light Fault) HVSL1 ( Silicon Rectifier) HRAVT ( Cab Fan/ Cab Heater) UBA ( Voltmeter Switch) HMCS2 ( Switch For Motor Cut Out) HVMT1( Blower Motor 1) HVMT2 ( Blower Motor 2) HMCS1 ( Switch For Motor Cut Out) “D” Type HRC Fuse: CCBA(35 A), CCLC/6 A), CCRA2(16 A), CCRA1(16 A), CCLF1(6 A), CCPT(16 A), CCVT(6 A), CCLF2(6 A), CC1VT(6 A) Fixed Coupler (19 no. Pin)

WORK INSTRUCTION FOR OVERHAULING OF TK PANEL + SWITCH BOARD ( POH/ POH + RC )

INCOMING CHECKING AND TESTING :-

(i) Visual Check of defect and deficiency of materials/ Components. (ii) Visual Check of damage & deformation of panel frame.

STRIPPING OF MATERIALS :-

(i) Open all the chute separator and arc chutes of EM contactors( EMC ) and open their coil connection as well as interlock connection. Open fixation/ foundation bolts of the entire EM fixation bar and dismount them from the panel.

(ii) Open all the electrical connection of SB 1+2, SBTR & TKBD terminals in TK panel and SB3 terminal in switch board and then dismount these terminals after unscrewing of fixation bolts in case of POH Work.

(iii) In case of Re-cabling, strip out all the cables by cutting of both end connection after removing/ Cutting the existing bunching tapes.

(iv) Open electrical connection of all the VS Diode, economy resistance, Push bottom switches ( BP, DJ, BP 2 DJ etc.), LTBA, Aux. capacitor Boxes, if available, TFS if any ZLE switches, LE 3 + 4 Lamp fitting etc. of TK Panel & all fuses, LECC, ECC, HOBA Knife Switch etc. from switch board.

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(v) After unscrewing all the above equipment, dismount them from front/ back side (TK – 1/TK-2) Panel and switch board. Other equipment such as rotary switches from switch board are to be stripped by Rotary switch section and relays are to be stripped by relay section.

(vi) Remove the power circuit bus bars from inside the TK Panel in R/C LOCO.

CLEANING, OVERHAULING AND ASSEMBLING :-

(i) Necessary mechanical repairing of TK Panel frame and switch board frame in LOCO, if required is to be made including stiffeners, relay base, capacitor base etc. in case of POH. In case of re cabling, do any mechanical alteration/ addition of panel frame, if required.

(ii) Clean the Panel frame both inside and outside as well as switch board frame with K.Oil and then petrol, soft nylon brush, duster and cotton waste. Clean all the LT control cables with petrol in case of POH work only.

(iii) Paint inside and outside of TK Panel as well as switch board, apply anti track varnish on all stiffeners of TK Panel and switch board.

(iv) Clean copper bus bar ends with steel wool/ emery paper and then do necessary tinning. Apply anti track varnish on bus bar except tinning portion.

Shop No. – 9A is Traction Motor shop of Kanchrapara Railway

Workshop, Where Periodic Overhauling (POH) of Traction Motor, Traction Motor Frame, Auxiliary Motor, Transformer of LOCO & EMU are done.

This Shop Has a Four Section : (iv) Traction Motor (v) Traction Motor Frame (vi) Auxiliary Motor (vii) Transformer

Mr. Debdas Goswami SSE is the incharge of Shop No.-9A and Others SSE and JE are as follows:

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Mr. A.K. Samaddar ( SSE/ Traction Motor) Mr. Debabrata Mukhopadhye (SSE/ TMF) Mr. T.K. Biswas (SSE/ Auxilary Motor) Mr. A.K. Mitra (SSE/ TFP[LOCO]) Mr. B.N. Bera ( SSE/ TFP [EMU])

Auxiliary Motors

Auxiliary Motors can be run AC or DC. It is not use for Traction Purpose but it helps to cooling of Transformer, Traction Motor, Compressor etc.

Various Type Of Auxiliary Motors are as follows: MPH (Transformer Oil Circulating Pump) :

The transformer tank is filled with oil and it absorbs the heat generated in the transformer and takes it away to the transformer oil cooling Radiator. The circulation of the oil is carried out by MPH. A flow valve with an electrical contact is provided in the oil circulating pipe. As long as the oil is circulating properly the contact on the relay remain closed. However in case of MPH fails or stop the relay contact open which in terns trips QPH relay. This strip the main circuit breaker(DJ) of the LOCO. Thus transformer is protected. Work : For Circulating of Oil Pump. Specification: It is used in both EMU and LOCOs.

Phase : 3 Phase Frequency : 50 HZ Voltage : 290V to 500 Volt Model : 1143L Size : 100 x 100 Discharge : 750 LPM/400LPM LOCO&EMU Speed : 2850 rpm HP : 4.3 Current : 7 Amp Insulation Class : H Winding Connection : Star Connection Manufacture : 23/12/2013 Makers: Flow well pumps & Meter, Bangalore, India

MVRH (Transformer Oil Cooling Radiator blower) :The MPH circulates the transformer oil through a radiator array on top of the transformer.

Air is blown over the radiator by the MVRH. This discharged the heat from the radiator into the atmosphere. A detecting relay is provided in the air stream of the MVRH. The flow detector is a diaphragm type device. The flow of air presses the diaphragm which closes the electrical contact. This relay is known as QVRH. In case the MVRH blower fails the Qtrips the DJ through the relay Q-118.Work : For Oil Cooling through Radiator. Specification: It is used in LOCOs.

Phase : 3 Phase Voltage : 415V (290V – 500V)Speed : 1470rpm Current : 40 Amp Winding Connection : Star ConnectionMake: Crompton Greaves Ltd.

MVSI 1 and 2( Rectifier cooling blower):One blower is provided for each of the rectifier blocks. As rectifiers are semiconductors,

they are very sensitive to heat and hence must be cooled continually. The switching sequence of the MVSI blowers is set up in such a way that unless the blower is rbe achieved. A detection relay of diaphragm type is also provided in the air stream of the

Fig: MPH Motor

MVRH (Transformer Oil Cooling Radiator blower) : The MPH circulates the transformer oil through a radiator array on top of the transformer.

Air is blown over the radiator by the MVRH. This discharged the heat from the radiator into the mosphere. A detecting relay is provided in the air stream of the MVRH. The flow detector is a

diaphragm type device. The flow of air presses the diaphragm which closes the electrical contact. This relay is known as QVRH. In case the MVRH blower fails the Q

118. Work : For Oil Cooling through Radiator.

It is used in LOCOs. Frequency : 50±3 %

500V) AMB : 65˚C KW/HP : 22.0/30.00 Insulation Class: H

Winding Connection : Star Connection Manufacture : June 2014 Make: Crompton Greaves Ltd.

Fig: MVRH Motor

MVSI 1 and 2( Rectifier cooling blower): One blower is provided for each of the rectifier blocks. As rectifiers are semiconductors,

they are very sensitive to heat and hence must be cooled continually. The switching sequence of the MVSI blowers is set up in such a way that unless the blower is running, traction can not be achieved. A detection relay of diaphragm type is also provided in the air stream of the

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The MPH circulates the transformer oil through a radiator array on top of the transformer. Air is blown over the radiator by the MVRH. This discharged the heat from the radiator into the

mosphere. A detecting relay is provided in the air stream of the MVRH. The flow detector is a diaphragm type device. The flow of air presses the diaphragm which closes the electrical contact. This relay is known as QVRH. In case the MVRH blower fails the QVRH releases and

One blower is provided for each of the rectifier blocks. As rectifiers are semiconductors, they are very sensitive to heat and hence must be cooled continually. The switching sequence

unning, traction can not be achieved. A detection relay of diaphragm type is also provided in the air stream of the

blowers. However the detection relay (QVSI 1 & 2) are interlocked with different relay known as Q45. This is a much faster acting relay withblower would trip the DJ in less than 1 sec.Work: For Ventilation of Silicon Panel. Specification: It is used in both EMU and LOCOs.

Frequency : 50 HZ HP : 4.3 Motor No.-05669 Manufacture : September 1991

MVSL (Auxiliary of the Smoothing reactor) :In WAM4 LOCOs only MVSL blower is provided for the cooling of

Work : Its Helps to Smoothing reactor. When current convert from DC to AC, a smooth curve is needed, hence it required. Specification: It is used in LOCOs.

Voltage : 415V (290V – 500V)Type: AB-50 Speed : 2880 rpm Manufacture : January 2005 Make: Ranjan Axle Blower, India

blowers. However the detection relay (QVSI 1 & 2) are interlocked with different relay known as Q45. This is a much faster acting relay with a time delay of only 0.67. Hence the failure of MVSI blower would trip the DJ in less than 1 sec. Work: For Ventilation of Silicon Panel.

It is used in both EMU and LOCOs. Type: AX 28-400 Speed : 2860 rpm Current : 4.7 Amp

Manufacture : September 1991 Make: Blower Sahal Haram Motor, India

Fig: MVSI Motor

MVSL (Auxiliary of the Smoothing reactor) : In WAM4 LOCOs only MVSL blower is provided for the cooling of smoothing reactors SL 1 & 2.

Work : Its Helps to Smoothing reactor. When current convert from DC to AC, a smooth curve is

It is used in LOCOs. 500V) Phase: 3 Phase

Wattage : 1850 Current : 4.6 Amps

Connection : Star Make: Ranjan Axle Blower, India

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blowers. However the detection relay (QVSI 1 & 2) are interlocked with different relay known as a time delay of only 0.67. Hence the failure of MVSI

Make: Blower Sahal Haram Motor, India

smoothing reactors SL 1 & 2.

Work : Its Helps to Smoothing reactor. When current convert from DC to AC, a smooth curve is

Fig: MVSL Motor

MVMT 1 and 2 (Traction Motors Cooling blower) :In normal operation of traction motor generates a lot of Heat. This heat is dissipated by

two blowers namely MVMT 1 and 2. Which force air through a duct into the traction motors of bogie 1 namely TM1, TM2, TM3 and bogie 2 namely TM4, TM5, TM6 respectivelymotor cooling blowers required a large quantity of air which is taken from vents in the side walls of the LOCO. Work : For traction Motor Cooling Purpose. Specification: It is used in LOCOs.

Phase : 3 Phase Voltage : 290V to 500 Volt Frame : C200M Speed : 2955 rpm Current : 46 Amp Winding Connection : Star ConnectionMakers: Crompton greaves Ltd, India

MCP 1,2 & 3 (Air Compressors) :

Electric LOCOs need compressed air at a pressure ranging from 6kg/cm² to 10kg/cm². Compressed air is used for the LOCOs won air brake system as also for the train brakes for raising the Pantograph, Operating the power switch gear incontactors, Change over Switch, Windscreen wipers, Senders the compressed air is obtained by providing 3 air compressors, each having capacity to pump 100 Lt. of air per minute.Work : For main compressor ( Air pressure build u Specification : It is used in LOCOs.

Phase : 3 Phase Voltage : 415Volt Speed : 970 rpm Current : 24 Amp Winding Connection : Star ConnectionMakers: Crompton greaves Ltd, India

MPV 1 & 2 ( Vacuum Pumps):

Fig: MVMT Motor

MVMT 1 and 2 (Traction Motors Cooling blower) : In normal operation of traction motor generates a lot of Heat. This heat is dissipated by

two blowers namely MVMT 1 and 2. Which force air through a duct into the traction motors of bogie 1 namely TM1, TM2, TM3 and bogie 2 namely TM4, TM5, TM6 respectivelymotor cooling blowers required a large quantity of air which is taken from vents in the side

Work : For traction Motor Cooling Purpose. It is used in LOCOs.

Frequency : 50 HZ Motor No.: 26 KD2-MVMT

AMB: 65˚C KW/HP : 26/35 Insulation Class : H

Winding Connection : Star Connection Manufacture : July 2014 Makers: Crompton greaves Ltd, India

& 3 (Air Compressors) : Electric LOCOs need compressed air at a pressure ranging from 6kg/cm² to 10kg/cm².

Compressed air is used for the LOCOs won air brake system as also for the train brakes for raising the Pantograph, Operating the power switch gear inside the LOCO such as power contactors, Change over Switch, Windscreen wipers, Senders the compressed air is obtained by providing 3 air compressors, each having capacity to pump 100 Lt. of air per minute.Work : For main compressor ( Air pressure build up purpose)

It is used in LOCOs. Frequency : 50 HZ Model : M0409415 KW:10.4 Insulation Class : H

Winding Connection : Star Connection Manufacture : 23/12/2013Makers: Crompton greaves Ltd, India

MPV 1 & 2 ( Vacuum Pumps):

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In normal operation of traction motor generates a lot of Heat. This heat is dissipated by two blowers namely MVMT 1 and 2. Which force air through a duct into the traction motors of bogie 1 namely TM1, TM2, TM3 and bogie 2 namely TM4, TM5, TM6 respectively. The traction motor cooling blowers required a large quantity of air which is taken from vents in the side

MVMT

Electric LOCOs need compressed air at a pressure ranging from 6kg/cm² to 10kg/cm². Compressed air is used for the LOCOs won air brake system as also for the train brakes for

side the LOCO such as power contactors, Change over Switch, Windscreen wipers, Senders the compressed air is obtained by providing 3 air compressors, each having capacity to pump 100 Lt. of air per minute.

23/12/2013

In LOCOs equipped to haul vacuum braked trains, two vacuum pumps are also provided of which at least 1 is running in normal service and sometimes both may have to be run if train breaks are required to be released in a hurry

MVRF / MVRB ( Dynamic braking resistance cooling blower) :

In LOCOs equipped with internal dynamic braking resistances, MVRF blower are provided for cooling the resistance during braking. While all the auxilisupply provided by the ARNO Converter / SIV / Motor alternator Set, The MVRF blower runs of the supply derived from the output of the traction motor itself and is connected in parallel to the dynamic braking resistances. Specification: It is DC series motor with blower used in LOCOs.

Phase : 3 Phase Voltage : 450Volt AMB : 55˚C Speed : 2950 rpm Current : 75 Amp Make: Danlat Ram Industries, India

MCPA (BABY COMPRESSOR) :The foot mounted motor is series wound with four poles. A weak shunt field is provided

to limit the no load speed to safe valve thus safe guarding the unit coupled to the motor. The motor front cover is designed to provide a spigot mounting for the crankcase. The radial box type brush holders are mounted on the insulated rocker arm and can be removed without disturbing the rare cover. The armature is dynamically balanced and is supporteduty ball bearings. The entire winding is dipped in varnished to get good insulation properties. A protection cover is provided to protect commutator and brush gear. An oil seal is provided to prevent crank case oil entering into the motor.

For working of baby compressor (MCPA) to build up pneumatic Pressure. For raising of Pantograph. For closing of DJ (de jointer) Parts of Baby Compressor : (i) Crankcase, (ii) Cylinder, (iii) Piston, (iv) Silencer, (v) Terminal Casing, (vi) Rocker Ring

In LOCOs equipped to haul vacuum braked trains, two vacuum pumps are also provided of which at least 1 is running in normal service and sometimes both may have to be run if train

eaks are required to be released in a hurry

MVRF / MVRB ( Dynamic braking resistance cooling blower) : In LOCOs equipped with internal dynamic braking resistances, MVRF blower are provided

for cooling the resistance during braking. While all the auxiliary machine run on the power supply provided by the ARNO Converter / SIV / Motor alternator Set, The MVRF blower runs of the supply derived from the output of the traction motor itself and is connected in parallel to the dynamic braking resistances.

It is DC series motor with blower used in LOCOs. Frequency : 50 HZ Cooling – Air Closed KW : 30 HP : 40 Insulation Class : H

Ram Industries, India

Fig: MVRF/MVRB Motor

MCPA (BABY COMPRESSOR) : The foot mounted motor is series wound with four poles. A weak shunt field is provided

to limit the no load speed to safe valve thus safe guarding the unit coupled to the motor. The tor front cover is designed to provide a spigot mounting for the crankcase. The radial box

type brush holders are mounted on the insulated rocker arm and can be removed without disturbing the rare cover. The armature is dynamically balanced and is supporteduty ball bearings. The entire winding is dipped in varnished to get good insulation properties. A protection cover is provided to protect commutator and brush gear. An oil seal is provided to prevent crank case oil entering into the motor.

For working of baby compressor (MCPA) to build up pneumatic Pressure. For raising of Pantograph. For closing of DJ (de jointer)

: (i) Crankcase, (ii) Cylinder, (iii) Piston, (iv) Silencer, (v) Terminal

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In LOCOs equipped to haul vacuum braked trains, two vacuum pumps are also provided of which at least 1 is running in normal service and sometimes both may have to be run if train

In LOCOs equipped with internal dynamic braking resistances, MVRF blower are provided ary machine run on the power

supply provided by the ARNO Converter / SIV / Motor alternator Set, The MVRF blower runs of the supply derived from the output of the traction motor itself and is connected in parallel to

The foot mounted motor is series wound with four poles. A weak shunt field is provided to limit the no load speed to safe valve thus safe guarding the unit coupled to the motor. The

tor front cover is designed to provide a spigot mounting for the crankcase. The radial box type brush holders are mounted on the insulated rocker arm and can be removed without disturbing the rare cover. The armature is dynamically balanced and is supported by two heavy duty ball bearings. The entire winding is dipped in varnished to get good insulation properties. A protection cover is provided to protect commutator and brush gear. An oil seal is provided to

For working of baby compressor (MCPA) to build up pneumatic Pressure. For raising of

: (i) Crankcase, (ii) Cylinder, (iii) Piston, (iv) Silencer, (v) Terminal

Fig: MCPA Motor for LOCO

ARNO Converter : This is a rotary converter which has a combined set of winding & is used to convert the single phase supply from tertiary winding various auxiliary machines in the LOCO. ARNO is basically a split stator for the generating phase. In a induction motor, the rotating field of stator creates a corresponding field in the rotor squirrel cage too which cause the rotor to slip speed which is slightly less than synchronous speed. However this rotating field of the rotor is additionally utilized in the ARNO to create power in the generating phase winding which gives the three phase output of the ARNO convemotoring phases carry the load as well supply currents of the ARNO in opposite direction which cause a net reduction in the actual current carried by the winding in the stator but the generating phase carries only the load current which cause a voltage drop in the generating phase. Specification: S.R. No.: 2531 Single Phase Input : 150 KVA 380 Volts 395 Amps Frame – VA 330 Cycle - 50˚c Make : Jyoti Ltd., Varoda, India

Fig : Circuit Diagram of Arno Converter

Fig: MCPA Motor for LOCO Fig: MCPA Motor for EMU

This is a rotary converter which has a combined set of winding & is used to convert the single phase supply from tertiary winding of the LOCO transformer to 3ɸ AC which is fit for use by the various auxiliary machines in the LOCO.

ARNO is basically a split – phase induction motor with an additional winding on the stator for the generating phase. In a induction motor, the rotating field of stator creates a corresponding field in the rotor squirrel cage too which cause the rotor to slip speed which is slightly less than synchronous speed. However this rotating field of the rotor is additionally utilized in the ARNO to create power in the generating phase winding which gives the three phase output of the ARNO convertor. In the stator winding of the ARNO, the motoring phases carry the load as well supply currents of the ARNO in opposite direction which cause a net reduction in the actual current carried by the winding in the stator but the

ly the load current which cause a voltage drop in the generating

: S.R. No.: 2531 Three Phase Output : 120 KVA 380 Volts 190 Amps RPM : 1495 Connect to Star

Make : Jyoti Ltd., Varoda, India

Fig : Circuit Diagram of Arno Converter

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Fig: MCPA Motor for EMU

This is a rotary converter which has a combined set of winding & is used to convert the single AC which is fit for use by the

phase induction motor with an additional winding on the stator for the generating phase. In a induction motor, the rotating field of stator creates a corresponding field in the rotor squirrel cage too which cause the rotor to start rotating at a slip speed which is slightly less than synchronous speed. However this rotating field of the rotor is additionally utilized in the ARNO to create power in the generating phase winding which gives

rtor. In the stator winding of the ARNO, the motoring phases carry the load as well supply currents of the ARNO in opposite direction which cause a net reduction in the actual current carried by the winding in the stator but the

ly the load current which cause a voltage drop in the generating

Three Phase Output :

380 Volts

Work instruction of auxiliary Motor Section : Scope : Overhauling of Auxiliary motors of LOCOMOTIVE & EMU motor coaches Procedure : Incoming Testing, Dismantaling & Overhauling

(i) Check the motor visually and its insulation by 500V magger.(ii) Carry on SCT test on the stator.(iii) Remove the air duct and impeller with suitable puller .(iv) Run the motor at rated voltage on load and check the sound.(v) remove the end cover slowly with the help of snappers and wooden mallet.(vi) Take out the rotor and remove the bearing from it with the help of puller.(vii) Clean the stator and rotor well whi(viii) Check the rotor bar of any crack, flash marks damages/Cracks of cooling fan, impeller

locking threads, keyway.(ix) Check the condition of winding and cleanliness of rotor.(x) Measure the bearing Seat of the shaft wi(xi) Clean the end cover with Kerosene and cloth.(xii) Measure the bearing housing with dial bore gauge.

Assembly & Final Testing: (i) Bake the stator and rotor at 120 ± 10 degree centre grate for 8 to 12 hours (ii) Apply one lout of insulating varnish on winding over hang portion and allow it cool to room temperature. (iii) Fit new bearing on the rotor shaft for LOCO aux. motor &aux. motor by heating the bearing at induction RR-3 grease. (iv) Insert the rotor into the stator. (v) Assemble the end shields on both sides of the motor by tightening the bolts. (vi) Rotate the shaft by hand and check its rotation is free from anobstruction if so, take out the rotor & repeat the procedure again. (vii) Run the motor at rated voltage on no load and check sound. (viii) Insert the key on shaft and mount the fan.

(viii) Tighten the fan mount bolt and ensure that the fan position and paint it fit the duct wherever necessary.

Fig : ARNO Converter

Work instruction of auxiliary Motor Section :- Overhauling of Auxiliary motors of LOCOMOTIVE & EMU motor coaches

Incoming Testing, Dismantaling & Overhauling (i) Check the motor visually and its insulation by 500V magger. (ii) Carry on SCT test on the stator. (iii) Remove the air duct and impeller with suitable puller .

the motor at rated voltage on load and check the sound. (v) remove the end cover slowly with the help of snappers and wooden mallet.(vi) Take out the rotor and remove the bearing from it with the help of puller.(vii) Clean the stator and rotor well which compressed air and orion 77. (viii) Check the rotor bar of any crack, flash marks damages/Cracks of cooling fan, impeller

locking threads, keyway. (ix) Check the condition of winding and cleanliness of rotor. (x) Measure the bearing Seat of the shaft with the help of outside micrometer.(xi) Clean the end cover with Kerosene and cloth. (xii) Measure the bearing housing with dial bore gauge.

(i) Bake the stator and rotor at 120 ± 10 degree centre grate for 8 to 12 hoursii) Apply one lout of insulating varnish on winding over hang portion and allow it cool to

(iii) Fit new bearing on the rotor shaft for LOCO aux. motor & on condition basis in EMU motor by heating the bearing at induction heater, cool the bearing & apply servo gen

(iv) Insert the rotor into the stator. (v) Assemble the end shields on both sides of the motor by tightening the bolts.(vi) Rotate the shaft by hand and check its rotation is free from an

so, take out the rotor & repeat the procedure again. (vii) Run the motor at rated voltage on no load and check sound. (viii) Insert the key on shaft and mount the fan.

Tighten the fan mount bolt and ensure that the fan properly sealed on its paint it fit the duct wherever necessary.

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Overhauling of Auxiliary motors of LOCOMOTIVE & EMU motor coaches

(v) remove the end cover slowly with the help of snappers and wooden mallet. (vi) Take out the rotor and remove the bearing from it with the help of puller.

(viii) Check the rotor bar of any crack, flash marks damages/Cracks of cooling fan, impeller

th the help of outside micrometer.

(i) Bake the stator and rotor at 120 ± 10 degree centre grate for 8 to 12 hours ii) Apply one lout of insulating varnish on winding over hang portion and allow it cool to

on condition basis in EMU heater, cool the bearing & apply servo gen

(v) Assemble the end shields on both sides of the motor by tightening the bolts. (vi) Rotate the shaft by hand and check its rotation is free from any mechanical

properly sealed on its

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(x) Keep the assembled motor on test bench and tighten the foundation. (xi) Connect the 3Phase 415 ± 22.5% volt ac supply to the motor terminal for LOCO

Auxilary motors. For EMU motor coaches connect the capacitor in series with the starting winding and the phase and neutral of 220 volt AC the motor terminal.

(xii)Switch on the motor by switching “ ON ” the MCB. (xiii) Ensure the motor is rotating in proper direction and record the current. (xiv) Measure the insulation resistance, the value should not be less than 10 M Ω. (xv) Paint the motor with brush externally and dry it.

Different Type Of Test For Auxiliary Motors : (i) Winding to Winding Test, 3ɸ Motor, For 1ɸ a Identical motor is needed. (ii)Earth fault Test (iii)SCT Test (a) Inter Turn Short test (b) Open circuit Test (c) Coil to Coil Short in same phase (d) Phase to phase short

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Traction Motor Traction motor is one of the most important equipment of electric locomotives. Traction motor type HS-15250 A was specially dev99eloped by M/s Hitachi for Indian Railways. This traction motor is being used in AC locomotives type WAG-5, WAG-7, WAP-4 and AC/DC locomotives type WCAM-3. Mainly DC Series Motor is used as traction motor as its starting torque is high enough to provide tractive effort. Different Parts of Traction Motor: FRAME:- This is a magnetic steel cast member, on the commutator side. Opening have been provided for upper air inlets & lower inspection covers. The terminal box is situated above the axle side. POLE:- The mail pole are built up of magnetic laminations 1m tick, held together by drown steel retaining pins welded to the end plates the assembly is fixed to the frame by 3 screws the commutating pole are also built up from 0.5mm thick magnetic sheets with class it varnish insulation. The four inter segment stacks are supported by 3 intermediate supports & two end supports & assembled by two drown steel rivets. The stack assembly is fixed to the frame by three screws. On the main pole s every second lamination is insulated with h-class varnish. FIELD COIL:- The conductor is of high conductivity electrolyte copper, ground insulation is by kepton tape followed by glass mica, glass silicon tape & F,G tape in turn insulation is nomex silicone impregnated paper. ARMATURE STACK:-

These are composed of magnetic steel laminations of 0.5 mm thick insulated by class H varnish. The punching are keyed to the armature shaft. Assembled hot in a process, the laminations are maintained by a cast steel armature head at one end and the other end by the cast steel armature sleeve retained on the shaft by set ring and rotating ring. COMMUTATOR:-

The segment are in silver-copper alloy separated by micanite. The segment are assembled on the collector ring and maintained by a mobile cone with insulting micanite cones. Each complete assembly is secured by 20 screws.

ARMATURE WINDING:-

It is composed of high conductivity electrolytic copper conductor with 2/3 lap kapton, bunch insulation Is made by –

(1) Glass-mica silicon tape on the involute portion (2) Nomex –silicon mica upper in the slot portion The coil are maintained in the slot by moulded directs slot wedges or laminated fibre slot wedges and by polyglass tape.

BRUSH HOLDER:- The 6 brush holders are carried on a rotery brush holder ring whose positioning & locking is

obtained by means a special screw inverse threaded. Inspection of the brush holders are

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carried out through inspection door. The connection between stator and brush holder is assured by flexible connector. ARMATURE BEARING:-

The armature is supported on two roller bearing mounted on cast steel end shields. An inspection panel on the commutator side end shield allows access to the brush holder insulated supports. Cooling air is evacuated through the armature head & expended metal at the pinion en shield. Parallel roller are fitted TERMINAL BOX:- This is situated on the upper part of the motor frame axle side a removable cover gives access to the connection. Rating:- Continuous 535V 340A 1260 R.P.M Insulation (Armature) H Insulation Clean (Field) F Insulation Level 1000V Construction:- The armature core is built up from electrical quality varnished sheet steel lamination assembled on the shaft with interference fit and consolidated under pressure. The armature has a forty percent equalization. The armature coils are capton covered. The armature and equalizer coil leads are TIG welded to commutator riser. The armature coil are held down in the core slots by Epoxy glass wedges and the end winding are squired by Res-i-glass bands. The wound armature s finally vacuum pressure impregnated by insulating varnish. The commutator is of arch bound construction built up with hard drawn silver bearing copper segment which are insulated with micanite segment and are assembled with mounded mica insulation between steel V-ring. After assembly, the commutator is statically and dynamically seasoned to ensure stability. The complete armature is dynamically balanced. The commutator outer mica V-ring is protected with anti-creepage tape/ring. The high permeability cast steel or fabricate magnate frame is machined to ensure aliganment of the end shield, pole bores and alxe-way bores. The main pole are built from steel lamination rivetted together Main pole and interpole coil are epoxy insulated and bonded to pole bodies using epoxy resin. This improve heat dissipation. There are four brush holder per motor is carrying to split carbon brushes. The brush holder is and integral casting having a single adjustable spring for each brush to provide the correct brush pressure. The brush holder is secured to the magnet frame by FRP moulded insulated pins. The rubber top carbon brushes are split type to ensure better contact the commutator. Arching horns are provided near the brush holders to minimize the damage in an event of a flashover. The armature is supported on two grease lubricated rollers bearing. Bearing assemblies are sealded type, thereby necessitating lubrication in about two years. The armature is located axially by the commutator end bearing, while the pinion end bearing is capable of taking are any axial play between armature and frame. The axle suspension bearing is highly leaded bronze shell type one half of the bearing is keyed to the axle cap to prevent rotation and to align the oiling window. The oil lubrication is provided by spring loaded wick assembly of the axle lubricator. The pinion which is shrunk on the armature shaft, drives the loco axle through a spur gear wheel which is pressed on to the axle. The gearcase is of welded steel construction and is

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in two halves, which are bolted together. The complete gearcase is supported on the motor frame and endshield PE. The joint between the gearcase halves are baffled and grooved to carry felt sealing rings so as to prevent ingress of dust and any other foreign materials and the escape of the gear lubricant. The motor Is self ventilated and the fan is mounted on CE. Shaft extension. Air enters the motor through a duct system connected to an opening provided in fan chamber and assembled on the motor frame at the commutator end. The cooling air then sucked by fan flows in two parallel paths, one under the commutator through the armature core ducts and the other along the outside of the armature and between the field coil and is discharged through the opening provided at the penion end of the fream. No Load Testing Procedure Of BHEL, Hitachi, Tao Traction Motors :

Parameters Checked Standard Value For

BHEL Standard value For

HITACHI Standard Value For

TAO

Starting Voltage / Current

2 – 4Volts/ 25 – 40 Amps

4 – 6 Volts/45 – 65 Amps

3 – 4 Volts/ 40 – 60 Amps

2 Hr No – Load run test at rated RPM

1500 895 1095

Voltage/ Current on rated RPM

84 – 86 Volt/ 35 – 40 Amps

70 – 72 Volt/ 45 – 48 Amps

68 – 72 Volt/ 45 – 50 Amps

Maximum Temperature rise

Note maximum temperature

Note maximum temperature

Note Maximum Temperature

Decrease Stable Temperature

Note Minimum Temperature

Note Maximum Temperature

Note Maximum Temperature

Ambient Temperature Note Ambient Temperature

Note Maximum Temperature

Note Maximum Temperature

Temperature Rise 35 – 40 35 – 45 35 – 45

Vibration(mm/sec) by vibration Pen

0 to 1.4 Green 1.5 to 3.5 Yellow

3.6 to above – Red

a) 0 to 1.4 Green b) 1.5 to 3.5 Yellow

3.6 to above Red

0 to 1.4 Green 1.5 to 3.5 Yellow 3.6 to above Red

Assembly of traction Motor of type 4610AZ, HS – 15250A &TAO – 659 : (i) Keep the traction motor Yoke on assembly stand. (ii) Tilt the armature vertically and lift the armature assembly from wooden stand. (iii) Gradually insert the armature into the magnet frame carefully then fix the CE and shield on the magnet frame. (iv) Tight the PE and shield bolt crosswise with the help of torque wrench. (v) Fit the brush holder and check the gap between the brush holder and commutator permissible limit 1.6 to 3.2 mm. (vi) Check the ARC horn and ARC horn gap. Permissible limit 10 – 11 m. If the ARC horn defective change it. (vii) Check the clearance between commutator rise to brush holder face and check not rubber with raiser.

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(viii) Insert the carbon brush in the brush holder and check face movement of the carbon brush connect the pig tail with brush holder. (ix) Fit the inspection cover and point back side lower from stand using crane on testing bay. Work Instruction Of traction Motor Section:- Scope : Overhauling of EMU/LOCO traction Motor Procedure : 1.Incoming Checking of Traction Motor :

(i) Inspect the traction motor for any external mechanical damage, defects and deficiencies, condition of pinion. (ii) Inspect the traction motor for any axle suspension area damage. (iii) Check the cable cleat, cable, E/brush, E/brush fixation hole etc. (iv) Check the IR value of field coil and armature to the respect to earth with 1000 volt megger. (v) Check the commutator visually for any spark or end flash mark. (vi) Check the condition of brush holder. (vii)Check the vibration or bearing noise by running the TM for five minute by run at 1500 rpm.

2. Striping of EMU Traction Motor(460IAZ) :

(i) Dismantle of the air duct by removing the bolt size M – 16x 35 and remove the commentator inspection covers. (ii) Open the TM Fan chamber and check the condition of thread of the bolt and holes for any worn- out for any damage of threads. (iii) Remove the sealing wire from outer bearing cap ( PE Side) and adapter plate ( CE Side ). (iv) Remove the lock Nut 82.5 mm and lock plate. Remove the cooling fan with puller. (v) Check the fan blade for any damage or crack check the thread holes, key slot and hub dia. of the Fan for any deformation. (vi) Remove the pinion wiper PE wiper CE, With puller remove the adapter plate, Bearing cap PE by removing the Allen Bearing M12 x 40. Check all the fitting, pinion. (vii) Remove the PE and Shield bolt M-20 x 50 and remove PE end shield carefully so that the bearing not damage. Remove the arm with the help of eye bolt carefully. So that it does not rub with stator poles. (viii) Remove the bearing from the cartridge with the help of puller and check the condition

of bearing End shield block. Bearing cap etc. for any damage / cracks or threads damage.

Overhauling Of Bearing : (i) At the time of dismantling the traction motor, Special case should be taken to collect and stored the bearing grouped as per their identification and also along with corresponding inner race and outer race to avoid incorrect assembly or mismatches. (ii) Wiped out the coagulated grease with soft cloth, then the bearing fully depend into ORION- 776 or Kerosene Oil for one day long. Coagulated greases and foreign materials if any is removed by blowing compressed, air with IRION – 77/ Kerosene Oil from the

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inaccessible part of Bearing till bearing, till bearing cleaned up to the mark by checking visually. (iii) Finally the bearing are depend into a container which contains fresh IRION – 77 / Petrol and the rest particle of dust and grease are removed by rotating the rollers by hand, so as to residual unwanted materials come out from the inaccessible part of the bearing as well as remove

traces of kerosene oil. At the time of final cleaning compressed air is not used to avoid the moisture contamination with the bearing part as the compressed air is not dry and free moisture. After completing the above procedure the bearing are taken out from the container and wiped off the solvent thoroughly with the help of new soft cloths. (iv)Examine all the rollers freely rolling or not. (v) Visual checking is done to check the stretch mark, pit mark and score mark, dis-colouring on the functional surfaces i.e. rolling elements and race ways. (vi) Clean the inner racer, out racer and roller and examine for any crack score, dislocation and closely observe for any air hair line cracks. (vii) If any inner race found crack then changed the bearing. (viii) Check the radial clearance as per recommended value of the PE & CE bearing and record it in the register. (ix) If the clearances are not within the limit replace it with a new bearing. Date of insulation should be marked on the new bearing by itching pen and record it in bearing resister. (x)Record the bearing insulation date in bearing register and itch the same on outer racer.

Stripping of LOCO Traction Motor ( HS – 15250A & TAO – 659 ) :

(i) After incoming checking dismantle the bearing stopper, pinion stopper plate bolts & lock plate for dismantling of pinion and send to clearing area for clearing. (ii) Remove the outer bearing cover, outlet bearing stopper / retaining plate of PE side and send to clearing area for clearing. (iii) Stand the motor pinion side top position for remove pinion end Shield carefully to avoid any damage of the bearing and send to clearing area for clearing. (iv) Remove the Arm with the help of Eye bolt carefully so that it does not rub with starter poles. (v) Turn the CE end top position with the help of crane for removing the CE End shield brush holder and brush holder revolving ring after removing the BHRR locking bolt and send to clearing area for clearing. (vi) Remove the outer bearing cover, outer bearing stopper of CE side and send to clearing area for cleaning.

Overhauling of Traction motor end component :-

(i) Scrap the sludge, coagulated grease with the help of a meta scrapper and steel wire brush from the end components and fan chamber, air duct, impeller, adopter plate and all the inspection covers, earth return brush holder. (ii) To moist all the spare parts by Kerosene oil applied with a brush and wipe out with jute or cloth afterwards.

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(iii) Clean thoroughly using moistened jute or cloth by Kerosene oil and ensure that there is no dirt or sludge inside the bearing components and other metal parts. (iv) Check the condition of the end shield block, DPT test should be done in the welded portion of the end shield block. (v)Check the end Shield fixation hole is elongated or not. If elongated, then replace it with new one.

(vi) Measure the bearing housing dia. and bore of the end shield by Go, Not Go gauge or inside micrometer. (vii)Examine all threaded hole of end components to be checked, if found worn out then replace it with new one. (viii)Visually checked the condition of bearing housing of end component and bore, which is related with armature shaft for smooth surface damage etc.

Overhauling of Brush Holder assembly during POH :

(i) Clean the brush holder with petrol thoroughly to remove dust and carbon particle from brush holder. (ii) Check the brush holder assembly visually for any flashing / damage. (iii) Check the condition of arcing stud for any damage melt if found damage replace with new one. (iv) Check the condition of the brush holder insulator in case of EMU traction Motor if found damage replace with new. (v) Check the condition brush holder, pocket if any flashing mark or Pilting mark rectifies all and checking should be done with new carbon brush inserting in to the pocket. (vi) Check the slot of the brush holder fixation in case of LOCO brush holder if damage/ not matching replace with new one. (vii) Replace all the spring in case LOCO as must change and check the brush holder spring pressure with the spring balance or weighing machine if low than the recommended value adjust the spring. (viii) Check the megger value with 1 kV megger and finally do the HV test at 3 kV for 1 Minute

Rate Of Traction Motor and No Load Testing Schedule : EMU / LOCO Traction motor type 4601AZ/BZ/BY/BX continuously rating- 535 V, 350Amp, 167Kw, 1260 RPM one hour rating – 535v, 380 Amp. 187 kW, 1182 RPM Type of Bearing – PE NU 326 bearing , CE NUP 318 bearing Testing Procedure :

Run the Traction motor at rated speed 1500 RPM for 45 minutes in clockwise and 45 minutes in anticlockwise run the Traction Motor at 2000 RPM for 15 minutes and 2275 RPM period for high speed. Check all the parameter. LOCO Type Traction Motor:

Traction Motor type TAO – 659 Continuous Rating : 750 v, 840 Amp, 585 kW, 1095 RPM

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One hour Ratting : 750V, 870 Amp, 650 kW, 1076 RPM Type of Bearing : PE NU 328 Bearing, CE NH 318 Bearing

Hitachi Type HS – 15250A :

Continuous Rating : 750V, 900 Amp, 630Kw, 895 RPM One hour Rating: 750 V, 960 Amp, 670Kw Type Of Bearing :PE NU 330 Bearing CE NH 324 Bearing

Testing:

Run the LOCO Traction motor at rated speed for 3 hrs. including high speed for a short period in case of high speed LOCO traction motor as bellows and check all the parameters testing. For high speed TAO-659 traction motor run the Traction motor and 2000 speed for a short period.For Hitachi Traction Motor run the Traction Motor for high speed LOCO at 2200 RPM FOR a short period. Flow Chart of Work Schedule of Traction Motor (Shop No 9A)

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Traction Motor Frame The high permeability cast steel or fabricated round magnet frame is machined to ensure alignment of the end shields, pole bores and axle way bores. Main pole and com pole coils are edge wound, curved epoxy insulated and bonded to pole bodies using epoxy resin. This improves heat dissipation and eliminates spring and support plates.

Fig: LOCO TM Frame Fig : EMU TM Fram

Frame has the following parts: Yoke :

Yoke is made of cast steel/cast iron. It serves double purposes (a)It provides mechanical support for the poles & acts as a protecting cover for the whole machine and (b)It carries the magnetic flux produced by the poles. The feet of the terminal box is welded to the frame afterwards. Pole Core & Poe Shoe :

The field magnets consist pole core & pole shoes. The pole spread out the flux in the air gap & also being of large cross section reduce the reluctance of the magnetic path.

It is mainly made of cast iron or cast steel but the pole shoe is laminated and is fastened to the pole face by means of counter sunk screw. In modern design the complete pole core and pole shoe are build of thin lamination of annealed steel which are riveted together under hydraulic pressure. The laminated poles may be screwed to the yoke by means of screws boltethrough the yoke and into the pole body or the holding screws are bolted into a steel bar which passes through the pole across the plane of the lamination. Pole Coils : The field coil or pole coil is consist of cuppercorrect dimension then the former is removed and wound coil is put into place over the core when current is passed through this coil, they electromagnetism the poles which produces the necessary flux that is cut by revolving armature conductor Rocker Assembly & Brush Holder: This motor is pole type motor and brush holders are mounted on the rocker ring that is fixed to the bearing bracket at commutator side by four bolts. The brush holders and carbrushes can be inspected by rotating the rocker ring until each brush holder comes to the inspection windows. The brush holders are mounted on the rocker ring by one insulating rod. Brushes can be changed without dismantling the motor. Flame retard(fluonlex) cable is used for brush gear connections. Interpole:

Fig: LOCO TM Frame Fig : EMU TM Fram

Frame has the following parts:-

Yoke is made of cast steel/cast iron. It serves double purposes (a)It provides mechanical acts as a protecting cover for the whole machine and (b)It carries the

magnetic flux produced by the poles. The feet of the terminal box is welded to the frame

The field magnets consist pole core & pole shoes. The pole shoe serve two purposes (a)It spread out the flux in the air gap & also being of large cross section reduce the reluctance of

It is mainly made of cast iron or cast steel but the pole shoe is laminated and is fastened to y means of counter sunk screw. In modern design the complete pole core and

pole shoe are build of thin lamination of annealed steel which are riveted together under hydraulic pressure. The laminated poles may be screwed to the yoke by means of screws boltethrough the yoke and into the pole body or the holding screws are bolted into a steel bar which passes through the pole across the plane of the lamination.

The field coil or pole coil is consist of cupper wire or strip, are former correct dimension then the former is removed and wound coil is put into place over the core when current is passed through this coil, they electromagnetism the poles which produces the

by revolving armature conductor

Rocker Assembly & Brush Holder:- This motor is pole type motor and brush holders are mounted on the rocker ring that is

fixed to the bearing bracket at commutator side by four bolts. The brush holders and carbrushes can be inspected by rotating the rocker ring until each brush holder comes to the inspection windows. The brush holders are mounted on the rocker ring by one insulating rod.

Brushes can be changed without dismantling the motor. Flame retardant modified ETFE (fluonlex) cable is used for brush gear connections.

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Fig: LOCO TM Frame Fig : EMU TM Frame

Yoke is made of cast steel/cast iron. It serves double purposes (a)It provides mechanical acts as a protecting cover for the whole machine and (b)It carries the

magnetic flux produced by the poles. The feet of the terminal box is welded to the frame

shoe serve two purposes (a)It spread out the flux in the air gap & also being of large cross section reduce the reluctance of

It is mainly made of cast iron or cast steel but the pole shoe is laminated and is fastened to y means of counter sunk screw. In modern design the complete pole core and

pole shoe are build of thin lamination of annealed steel which are riveted together under hydraulic pressure. The laminated poles may be screwed to the yoke by means of screws bolted through the yoke and into the pole body or the holding screws are bolted into a steel bar which

wire or strip, are former - wound fir the correct dimension then the former is removed and wound coil is put into place over the core when current is passed through this coil, they electromagnetism the poles which produces the

This motor is pole type motor and brush holders are mounted on the rocker ring that is fixed to the bearing bracket at commutator side by four bolts. The brush holders and carbon brushes can be inspected by rotating the rocker ring until each brush holder comes to the inspection windows. The brush holders are mounted on the rocker ring by one insulating rod.

ant modified ETFE

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This are small poles fixes to the yoke and spaced in between the main pole. They are wound with comparatively few heavy gauge copper wire turns and reconnected in series with the armature so that they carry full armature current. As interpole carry armature current their commutating EMF is proportional to the armature current this ensures automatic neutralization of reactance voltage which is also due to armature current. The main function of interpole are (a) Reduce cross-magnetization effect of armature reaction (b) Reduce spark. (c) Help in commutation HIGH CURRENT TEST OF BRAZED JOINTS AS PER RDSO /2011/EL/SMI/0271 Rev ‘0’ (For traction motor frames of HS15250A & Tao-659) The stators are first dismantled from the traction motor and cleaned properly so that high current injection test can be performed. Main Field Coil Circuit:- The insulation resistance of the field circuit is measured with 1000 V Megger. If insulation resistance >30 MΩ, then 500 A current from DC high current set is injected to the field circuit and voltage drop at motor terminals are measured and recorded. Compoles in Armature Circuit:- The positive & negative terminals for the rocker ring in armature circuit is shorted. The insulation resistance of the armature circuit is measured with 1000 V Megger. If insulation resistance >30 MΩ, then 500 A current from DC high current set is injected to the field circuit and voltage drop at motor terminals are measured and recorded. CONNECTION ARRANGEMENT (AS PER DRG NO. SKEL-4867)

Equipment reqd: (i)1000V Megger; (ii)Voltmeter(Range->0V-15V), (iii)Ammeter(Range->0A-1000A) (iv)DC High Current Injection Set (Range->0A-1000A) HIGH CURRENT TEST PARAMETERS If the recorded value found more than the specified value as mentioned in the above table, investigation is carried out thoroughly to detect faulty or bad brazed joints.

VOLTAGE DROP AT 30°C MP CIRCUIT CP CIRCUIT

HITACHI STATOR 4.48±0.2 V 4.00±0.2 V

TAO/TAOCHI STATOR 3.70±0.2 V 2.70±0.2 V

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TESTING PARAMETERS OF TRACTION MOTOR FRAME :

Work Instruction of Traction Motor Frame Section:- Scope: Overhauling of Traction Motor Stator Type 15250/TAO659. Procedure: (i) Clean the stator with recommended cleaning agent or kerosene oil. (ii) Check and replace the nose wiring plate. (iii) Check and replace the gear case lug bush and attend any mechanical defect in the frame. (iv) Check the MP/IP Coil fixing bolts gor any looseness if found lose same to be tighten with recommended torque and locking to be done to avoid free movement of bolt and pole shoes for rubbing mark visually with armature. (v) Check the IR or MP and IP with megger, it should be recorded. (vi) Check visually the surface insulation of MP and IP coil for peel off/ damaged. For further checking and works like replacement of wear plates and both gear case lugs, strengthening of both bottom and top gear case lugs and modification of bottom inspection covers works as per SMI or TSO to be done by sending to mechanical shop. Motor Type HS – 15250A/ TAO -659 or TAOCHI Stator : (i) Place the cleaned and good stator in baking oven and bake for 150˚C for 12 Hours . (ii) Varnish the baked stator by H class anti tracking finishing varnish. (iii) Place the varnished stator at test area for electrical testing. (iv) HV test at 2.5 KV and note leakage current. (v) Check IR by 1KV megger and note . (vi) Check coil resistance by MOM and Note. (vii) Check brazing joints by applying high current as per SMI. (viii) Check the polarity of the coils i.e. N pole / S pole. (ix) Check all threaded poles and re-tapped. (x) Check tightness of all MP and IP coil fixing bolts at specified torque. (xi) Replace all needle roller bearing for HS- 15250A stator.

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(xii) Seal all coil fixing bolts with M-Seal and anabond- 685 or Similar only. (xiii) For Sealing of bolts at housing area use anabond – 685 or similar only. (xiv) Carry Out D.P test at welded part of nose supporting bracket For HS -152508 Stators. Note all relevant data regarding the stator and dispatch to TM section For further work.

No Load testing of Traction motor of EMU/ Loco:

Responsibility : SE of the TM Section, Shop No: 9A/ KPA Procedure : (i) Place the assembled traction motor in test bench. (ii) Connect the terminals of traction motor to no load test machine. (iii) Connect the speed sensor properly. (iv) Switch on the supply and run the motor and observe Any unusual noise Excessive Chattering of carbon Brush. (v) If everything OK run the motor for 2 hrs at rated speed and high speed as mentioned below in case EMU/LOCO traction motor. Check the vibration by using vibration monitor( Bearing Echo Meter) and shall not be more the 35 db( Yellow Zone ). If exceeds run the motor again for 2 hrs. If no improvement dismantle and check again. (vi) Check the bearing temperature with thermometer shall not exceed ambient +25˚c. (vii) If exceeding chattering in carbon brush check the ovulate not more than 0.05 mm also check the bedding of carbon brush. (viii) If all parameters ok after the motor is ready for pinion fitment.

Repair reclamation of potted IP field coil (BHEL) : TYPE:- 4601AZ WORKING PROCEDURE:- (i) Place the coil on the table and cleaned. (ii) Test the coil with the help of SCT machine. (iii) Place the coil on pressing zig under press M/C with the help of clean. (iv) Remove the shoe the from the coil with help of press machine. (v) After remove the pole shoe from the coil for any damage. (vi) Strip the lamination with the help of knife and mallet. (vii) Clean the coil with send paper. (viii) Ground insulation done on coil with the help of GUAT-CN & 4FTNA & EGT tape. (ix) Sacrifice tape done with the help of 4FT & polyester tape and baked. (x) VPI done with HEW-290 varnish with the help of VPI plant. (xi) Baked after VPI at 150°C. (xii) Pole shoe cleanest. (xiii) Pole shoe fitted in the coil & light with pressuring plate. (xiv) Resin 823(A+B) mixed with 1:1 & paint in between core & coil. (xv) Varnish 821(A+B+C+D) mixed with 5. (xvi) Apply varnish TVA1410 at 70°C - 80°C. (xvii) Test IR value, D,E test, SCT. (xviii) Dispatch.

TRANSFORMER

INTRODUCTION : The transformer is a static device, which transform power from one AC circuit to

another AC circuit at same frequency. These circuits are conductively disjointed but magnetically coupled by a common time varying magnetic field. It can raise or lower the vowith a corresponding decrease or increase in current.

In all the electric locomotives, limiting the value of current during starting, speed control is achieved by supply of variable voltage to the traction motors. This variation of applied voltage can be carried out easily by the use of transformer along with tap changer provided in the locomotive.

Transformer is one of the most important traction equipment of AC EMU/MEMU/LOCO. It is double wound with primary and seconsandwich construction.

Current at 25 kV is taken from OHE to its primary winding via the pantograph, the vacuum circuit breaker and the high tension main bushing. The return path for this current is via the earthing brushes mounted in the axle cap of each traction motor and the running rails.The secondary winding of the transformer is in two sections, one section having five tapped sections, other being untapped. This arrangement gives a total twentyvarious connections of transformer tappings and voltage dropping reactors. This voltage, which is controlled by the tap-changing switch group, is applied to the silicon rectifiers, the full wave output of which is fed to the traction motors via t

Two tertiary windings, auxiliary I and II are provided. Auxiliary I, 266 V winding feeds the single phase a.c. auxiliary machines. Auxiliary II, 141 V winding supplies power to normal lights & fans, head lights stabilizer, the auxilia

The transformer is a static device, which transform power from one AC circuit to another AC circuit at same frequency. These circuits are conductively disjointed but magnetically coupled by a common time varying magnetic field. It can raise or lower the vowith a corresponding decrease or increase in current.

In all the electric locomotives, limiting the value of current during starting, speed control is achieved by supply of variable voltage to the traction motors. This variation of applied

n be carried out easily by the use of transformer along with tap changer provided in the locomotive.

Transformer is one of the most important traction equipment of AC EMU/MEMU/LOCO. It is double wound with primary and secondary windings interleaved together to give a

Current at 25 kV is taken from OHE to its primary winding via the pantograph, the vacuum circuit breaker and the high tension main bushing. The return path for this current is

hing brushes mounted in the axle cap of each traction motor and the running rails.The secondary winding of the transformer is in two sections, one section having five tapped sections, other being untapped. This arrangement gives a total twenty-two voltagevarious connections of transformer tappings and voltage dropping reactors. This voltage, which

changing switch group, is applied to the silicon rectifiers, the full wave output of which is fed to the traction motors via the smoothing reactor.

Two tertiary windings, auxiliary I and II are provided. Auxiliary I, 266 V winding feeds the single phase a.c. auxiliary machines. Auxiliary II, 141 V winding supplies power to normal lights & fans, head lights stabilizer, the auxiliary rectifier for main compressor motor

Figure : LOCO Transformer

Figure : EMU Transformer

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The transformer is a static device, which transform power from one AC circuit to another AC circuit at same frequency. These circuits are conductively disjointed but magnetically coupled by a common time varying magnetic field. It can raise or lower the voltage

In all the electric locomotives, limiting the value of current during starting, speed control is achieved by supply of variable voltage to the traction motors. This variation of applied

n be carried out easily by the use of transformer along with tap changer provided in

Transformer is one of the most important traction equipment of AC EMU/MEMU/LOCO. dary windings interleaved together to give a

Current at 25 kV is taken from OHE to its primary winding via the pantograph, the vacuum circuit breaker and the high tension main bushing. The return path for this current is

hing brushes mounted in the axle cap of each traction motor and the running rails. The secondary winding of the transformer is in two sections, one section having five tapped

two voltage steps by various connections of transformer tappings and voltage dropping reactors. This voltage, which

changing switch group, is applied to the silicon rectifiers, the full wave

Two tertiary windings, auxiliary I and II are provided. Auxiliary I, 266 V winding feeds the single phase a.c. auxiliary machines. Auxiliary II, 141 V winding supplies power to normal lights

ry rectifier for main compressor motor

The characteristic of Transformer is as follows: The transformer used in loco is a special type. It’s a hybrid of autotransformer and a transformer.

Fig :

In this transformer tapping is done on load on the primary side. The transformer has two secondary. One secondary is for the Arno or Static converter (SIV) supplying fixed 415V for Arno (a1-a8 & a0-a7) or 830V for SIV (a0 The other secondary is for traction motor (a3traction motor. There are 33 taps which sends are mainly for controlling the induced voltage in secondary. Thus the taps are used for speed regulation of traction motor by voltage regulation. The tapping are changed by a servomotor(SMGR) The transformer has three limbs containing the transformer winding56 discs and the other two 48.

The transformer is cooled by oil forced and air forced(OFAF).The whole transformer is immersed in oil. The core of transformer is formed by Cold Rolled Grain Oriented steel (CRGO).In EMU there is a tap changer which is on the secondary side of the transformer. Thus tapings are done on the secondary side.

The characteristic of Transformer is as follows:- The transformer used in loco is a special type. It’s a hybrid of autotransformer and a

Fig : Active part of transformer 5400 kVA

In this transformer tapping is done on load on the primary side. The transformer has two secondary. One secondary is for the Arno or Static converter (SIV) supplying fixed 415V for Arno

for SIV (a0-a8). For SIV the secondary terminal a1-a7 is shorted.The other secondary is for traction motor (a3-a4 & a5-a6). Each terminal supplies to 3

There are 33 taps which sends are mainly for controlling the induced voltage in ary. Thus the taps are used for speed regulation of traction motor by voltage regulation. The tapping are changed by a servomotor(SMGR) The transformer has three limbs containing the transformer windings. The first limb has

Fig : Winding of 5400 kVA

The transformer is cooled by oil forced and air forced(OFAF).The whole transformer is

immersed in oil. The core of transformer is formed by Cold Rolled Grain Oriented steel (CRGO).In EMU there is a tap changer which is on the secondary side of the transformer. Thus tapings are done on the secondary side.

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The transformer used in loco is a special type. It’s a hybrid of autotransformer and a

One secondary is for the Arno or Static converter (SIV) supplying fixed 415V for Arno a7 is shorted.

a6). Each terminal supplies to 3

There are 33 taps which sends are mainly for controlling the induced voltage in ary. Thus the taps are used for speed regulation of traction motor by voltage regulation.

s. The first limb has

The transformer is cooled by oil forced and air forced(OFAF).The whole transformer is immersed in oil. The core of transformer is formed by Cold Rolled Grain Oriented steel (CRGO).In EMU there is a tap changer which is on the secondary side of the transformer. Thus

The tapings are changed through RGR, i.e. via a resistance to avoid flashing during tap changing.

Fig : Transition Resistance of N 32 Tap changer(RGR LOCO)

The main work of the transformer is to supply step down voltage to auxiliary and traction motor. The transformer used in LOCO/EMU are of either 5400 or 3900KVA rated. The WAG7 & WAP4 use 5400KVA transformer and WAG5 & WAM4 use 3900KVA transformer. The makers of transformer are BHEL, CGS & NGEF. There are two types of transformers used in locomotives. One is 5400KVA another is 3900KVA. 5400KVA is used in WAG7, WAP4 3900KVA is used in WAG5, WAM4

Fig : EMU Tap changer

The tapings are changed through RGR, i.e. via a resistance to avoid flashing during tap

Fig : Transition Resistance of N 32 Tap changer(RGR LOCO)

The main work of the transformer is to supply step down voltage to auxiliary and

The transformer used in LOCO/EMU are of either 5400 or 3900KVA rated. The WAG7 & 5400KVA transformer and WAG5 & WAM4 use 3900KVA transformer.

The makers of transformer are BHEL, CGS & NGEF.

There are two types of transformers used in locomotives. One is 5400KVA another is

5400KVA is used in WAG7, WAP4 3900KVA is used in WAG5, WAM4

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The tapings are changed through RGR, i.e. via a resistance to avoid flashing during tap

The main work of the transformer is to supply step down voltage to auxiliary and

The transformer used in LOCO/EMU are of either 5400 or 3900KVA rated. The WAG7 & 5400KVA transformer and WAG5 & WAM4 use 3900KVA transformer.

There are two types of transformers used in locomotives. One is 5400KVA another is

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LOCO Transformer:

Make:-BHEL Type:- 5400

WINDINGS PRIMARY SECONDARY AUXILIARY

SERVICE

KVA Volts

5670 22500 2500

27500

5400 0-1000 [Tap 0-32] 0-1000 [Tap 0-29] 0-1000 [Tap 0-26]

2135 415 830 461 922

507 1014

Amps. 252.0 226.8 206.2

2700 325 293 266

Terminals A33-A0 a6-a5 and a4-a3

a1-a0 and a8-a7 or

a8-a0

Temperature rise oil/winding:- 450C/55oC Make:-NGEF Type:- 3900

WINDING PRIMARY SECONDARY AUXILIARY

SERVICE

KVA Volts

At No Load

4170 22500 25700 27500

3900 0-865 [Tap 0-32] 0-871 [Tap 0-29] 0-859 [Tap 0-26]

276

2389

2432

2476

Amps. 185.3 166.8 151.6

22250 2347

2312.5

2283.5

Terminals A33-A0 a6-a5 and a4-a3 a0-a1 and a7-a8

Temperature rise oil/winding:- 450C/55oC DIFFERENT PARTS OF TRANSFORMER : Core :

The core is a three limbed shell type construction, each limb being inter-leaved with the top and bottom yokes. The laminations are made from high-grade non-ageing silicon alloy cold rolled grain-oriented steel. After cutting and punching the sheets are deburred, stress relieved and varnished. Windings :

H.V. (primary), L.V. (secondary), and auxiliary (tertiary) windings are arranged on the centre limb and are inter-leaved to give a robust mechanical construction. Tapings are provided

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on secondary for voltage variation andare brought out individually for connection to an external tap changer switch group. Terminal Arrangement : The H.V. (primary) line terminal is brought out to the H.V. turret through the cover & connection is made to condenser bushing/ cable head bushing. The L.V. (secondary) terminals, 8 in number each capable of carrying 1280 amperes, are taken from the side of the tank through epoxy resinated terminal boards with copper bars embedded into it. Four terminals of two auxiliaries are taken through another epoxy resinated terminal board in Four terminals of two auxiliaries are taken through another epoxy resinated terminal board in a similar fashion as in the case of L.V. The primary earthing terminal is taken through a 6.6 KV porcelain bushing and is connected to earth. Tank : The tank is of welded mild steel plate construction, shot blasted on the inside and outside to remove the scale before painting. The tank is designed to withstand a pressure of 0.55 kg/sq.cm. Inside of the tank is coated with Copal varnish and the outside with three coats of high quality paint, comprising of a primary coat of anti-corrosive paint, an intermediate coat and a finish coat of battleship grey. Fittings : The following fittings are provided with transformer.

1.Conservator with oil gauge. 2. Silica-gel breather mounted on the conservator. 3. Buchholz relay 4. Thermostat 5. Relief vent 6. Drain valve 7. Filling holes 8. Filter valve 9. Oil inlet and outlet valves. 10. Drain plug with locking valves. 11. Air release plug. 12. Pressure Relief Valve (PRV) 13. Turret 14. Main Bushing

Conservator With Oil Gauge :

It is a drum containing transformer oil and is mounted in the HT compartment. It is connected to the transformer via the Buchholz protection relay. As the volume of oil of transformer tank expands and contracts according to heat produced, this expansion and contraction of oil causes the level of the oil in conservator to rise and fall. The aim of conservator is to - Maintain the oil level in tank - Provide space for the expansion of oil. An oil gauge indicator is also provided on one side of conservator drum with a scale having marking according to temperature. Breather :

It is attached to conservator tank and contains silica gel, which prevents the moist air from entering into the tank during contraction of oil. When oil is hot there is expansion and gas passes to atmosphere through it. When oil is cooled, there is contraction and the air enters in it. Air entering the breather is first drawn through an oil seal and passes upwards through the silica gel crystals to the connecting pipe at the top. During this upward passage of air, any

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moisture present is absorbed by the dry silica gel. The oil seal ensures that the gel absorbs moisture only when the transformer is breathing. Thus it prevents transformer oil from moisture contamination. Buchholz Relay :

A gas actuated double element Buchholz device (BUD) is fitted in the pipe connection between the conservator and the transformer tank in which the metal to metal (silver) contacts are used. Under normal conditions, it is full of oil. Buchholz relay is provided with an indicating flag and a mechanical latch so that when it is closed by operation of either FAST or SLOW contacts of the Buchholz device, it remains closed until the reset button is pressed. Contact BIR/1 is connected in the air blast circuit breaker (or VCB) circuit to trip in the event of a Buchholz operation and red ABB/VCB ‘OFF’ light is lit in the faulty unit. Relay BIR trips permanently and the transformer is disconnected from the supply through circuit breaker tripping if any of the following faults occurred:

a. Broken down core bolts. b. Shorted laminations. c. Bad contacts d. Over heating of some part of the windings. e. Falling of oil level arising from leakage. f. Ingress of air, through defects in the oil circulating system. g. Puncture of bushings. h. Short circuit between phases. i. Earth faults. j. Winding short circuits. k. Oil level falling below height of mounting position of the protector.

Thermostat :

The thermostat fitted is a type GM thermostat of Teddingation control with a range of 57/ 99˚C continuously adjustable and is set at 75°C. Undue rise in temperature of the transformer oil causes the transformer thermostat to operate, which in turn picks up the transformer thermostat relay (TTR). Operation of the relay TTR interrupts the feed to the motor contactors and also lights unit fault lamps in the faulty unit. When the transformer oil has cooled, the thermostat TT and the relay TTR return to normal position, allowing traction power to be restored, but leaving the flag indication to show that a trip has occurred. The flag can be reset by operation of a button on the relay. Pressure Relief Valve :

In case of severe fault in the transformer, the inter pressure may built up to a very high level which may result in an explosion of tank. To avoid such a contingency, a pressure relief valve is fitted on the transformer. It is springloaded and has contacts for giving visual indication and ABB/VCB tripping. When pressure in the tank rises above predetermined safe limit, this valve operates and performs following function:

a. Allows the pressure to drop by instantaneously opening a port of about 150mm dia. b. Gives visual indication of valve operation by raising a flag. c. Operates a micro switch which gives PRV trip indication by glowing LED and ABB/VCB tripping in the faulty unit. The valve restores its position as soon as the pressure in the tank drops below set limit. The flag and switch remain operated until they are reset manually.

Main Bushing : The 25 kV condenser type bushing assembly consists of three major parts viz. roof bushing, condenser sleeve and transformer bushing. Originally this type of bushing is oil filled. But due to

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failure of condenser bushing resulting in its bursting and splashing of hot oil on to the floor of motor coach and this hot oil often leads to the fire in the motor coach. For avoid fire hazered now Cable Head Termination (CHT) type is in service AC EMU/ MEMU.

Fig : Circuit Diagram of Transformer

TAP CHANGER Description:

The tap changer is directly built on to the transformer. The tappings of the transformer are brought out and arranged in circular fashion on an insulated contact plate. There are two rows of contact segments which are aligned on outer and inner circles of the contact plate. An arm which is known as selector arm is driven by a shaft at centre of the contact plate. two rollers are suited at the edge of the select arm. these rollers make connection between the respective segment in outer or inner rings. these rings are provided to front of the contact plate. the centre shaft which extends outside the tap changer casing is driven by an servo motor known as SMGR. The design of the air servo motor is such that ones the selector arm beings its movement, it can be stop only at the required tap( not in between two taps). The connection between the inner or outer ring to the transformer is being establish by means of CGR contactor.

METHOD OF OPERATION (THE ASEA BROWN

Although there are many types of OLTCs, the one mainly used on the Indian Railways locos has been designed by Asea Brown Boveri and even today is known as the Brown Boveri type N-32.

This model is a huge success and is used on all the locos.The general requirements and constraints encountered while designing an OLTC should

be clearly understood before going into the specific design of the Nwill also help in understanding the manner in which these have been dealt with in the Ntype Tap-Changer:

While the tap is being changed the output current must continue to flow.Any two taps must never be directly shorted because the existence of different voltages on the taps causes short-circuit level current to flow between the taps whichthe tap-changer can also cause severe damage to the transformer.

The tap-changer must be able to operate frequently without requiring extensive maintenance The N-32 tap-changer has been designed keeping in mind the above mentioned In the N-32 Tap-Changer all taps are terminated on a circular contact plate (see Fig. 1) with two concentric circles of contacts. In addition there are two contact rings surrounding the contacts. Two selector arms rotate over the contacts andthe outer contact segments and the outer contact ring and the other selector arm provides a short between the inner contact segments and the inner contact ring.These contacts rings are connected to the transitiIn addition a resistance (RGR) is also provided which is inserted momentarily during transition from one notch to another. This insertion and removal of the resistance is carried out by the central contactor CGR2. Operational details of the N-32 have been described beside each of the diagrams. In this picture the Transition Contactors (CGR 1, 2, 3) and the Transition Resistance (RGR) as also the selector drum of the Tap Changer are visible clearly. The slotted elemeare the RGR. In the front the small cylindrical device with a bluish color with a pipe coming out of its top between the selector drum and the CGR block is the PHGR. The PHGR is a small pump operated by compressed air and is uorder to remove impurities which occur in the oil due to particles breaking off from the selector arms and the tap segments due to frequent operation as also nominal arcing occurring during switching. To the right of the Selector Drum a small gear wheel is visible. This is the gear which connects with the Air Servo Motor (SMGR). This motor has been removed from this unit. The SMGR is an interesting study in itself. The shaft of the gear mentionemechanism in the tap-changer body which operates the selector arms in the drum as also the CGR contactors in a pre-determined and closely co

Figure : tap Changer Equipment

METHOD OF OPERATION (THE ASEA BROWN-BOVERI N-32 TAP-CHANGER) :Although there are many types of OLTCs, the one mainly used on the Indian Railways

locos has been designed by Asea Brown Boveri and even today is known as the Brown Boveri

This model is a huge success and is used on all the locos. quirements and constraints encountered while designing an OLTC should

be clearly understood before going into the specific design of the N-32 type Tapwill also help in understanding the manner in which these have been dealt with in the N

While the tap is being changed the output current must continue to flow.Any two taps must never be directly shorted because the existence of different voltages on the

circuit level current to flow between the taps which in addition to damaging changer can also cause severe damage to the transformer.

changer must be able to operate frequently without requiring extensive

changer has been designed keeping in mind the above mentioned Changer all taps are terminated on a circular contact plate (see Fig. 1) with two

concentric circles of contacts. In addition there are two contact rings surrounding the contacts. Two selector arms rotate over the contacts and the rings. One arm provides a short between the outer contact segments and the outer contact ring and the other selector arm provides a short between the inner contact segments and the inner contact ring. These contacts rings are connected to the transition contactors CGR1 and CGR3 respectively.In addition a resistance (RGR) is also provided which is inserted momentarily during transition from one notch to another. This insertion and removal of the resistance is carried out by the

32 have been described beside each of the diagrams. In this picture the Transition Contactors (CGR 1, 2, 3) and the Transition Resistance (RGR) as also the selector drum of the Tap Changer are visible clearly. The slotted elements behind the CGR contactors are the RGR. In the front the small cylindrical device with a bluish color with a pipe coming out of its top between the selector drum and the CGR block is the PHGR. The PHGR is a small pump operated by compressed air and is used to circulate the oil in the selector drum. This is done in order to remove impurities which occur in the oil due to particles breaking off from the selector arms and the tap segments due to frequent operation as also nominal arcing occurring during

tching. To the right of the Selector Drum a small gear wheel is visible. This is the gear which connects with the Air Servo Motor (SMGR). This motor has been removed from this unit. The SMGR is an interesting study in itself. The shaft of the gear mentioned above is connected to a

changer body which operates the selector arms in the drum as also the determined and closely co-coordinated sequence. The CGR contactors

49 | P a g e

CHANGER) : Although there are many types of OLTCs, the one mainly used on the Indian Railways

locos has been designed by Asea Brown Boveri and even today is known as the Brown Boveri

quirements and constraints encountered while designing an OLTC should 32 type Tap-Changer. This

will also help in understanding the manner in which these have been dealt with in the N-32

While the tap is being changed the output current must continue to flow. Any two taps must never be directly shorted because the existence of different voltages on the

in addition to damaging

changer must be able to operate frequently without requiring extensive

changer has been designed keeping in mind the above mentioned requirements. Changer all taps are terminated on a circular contact plate (see Fig. 1) with two

concentric circles of contacts. In addition there are two contact rings surrounding the contacts. the rings. One arm provides a short between

the outer contact segments and the outer contact ring and the other selector arm provides a

on contactors CGR1 and CGR3 respectively. In addition a resistance (RGR) is also provided which is inserted momentarily during transition from one notch to another. This insertion and removal of the resistance is carried out by the

32 have been described beside each of the diagrams. In this picture the Transition Contactors (CGR 1, 2, 3) and the Transition Resistance (RGR) as also the selector

nts behind the CGR contactors are the RGR. In the front the small cylindrical device with a bluish color with a pipe coming out of its top between the selector drum and the CGR block is the PHGR. The PHGR is a small pump

sed to circulate the oil in the selector drum. This is done in order to remove impurities which occur in the oil due to particles breaking off from the selector arms and the tap segments due to frequent operation as also nominal arcing occurring during

tching. To the right of the Selector Drum a small gear wheel is visible. This is the gear which connects with the Air Servo Motor (SMGR). This motor has been removed from this unit. The

d above is connected to a changer body which operates the selector arms in the drum as also the

coordinated sequence. The CGR contactors

50 | P a g e

also have a common drive shaft with rotating cams which ensure that the CGRs operate in their proper sequence.

In the bellow figure the tap-changer is shown at the position of notch 1 and 2.But its supplying only to notch 1.The long selector is at tap segment 1 which in turn is supplying to the outer contact ring while the short selector is at tap segment 2 and is supplying to the inner contact ring. This ring is connected to CGR3 which is open. During transition from notch 1 to notch 2, CGR2 closes first which brings the RGR into the circuit. Here I should point out that the RGR serves two purposes, first of which is to ensure that when two taps are to be connected together it is done through this resistance which tends to limit the short circuit current which occurs when any two or more taps are connected with each other. Second purpose is to ensure the continuity of supply to the Traction Motors which is carried through the common link above the three contactors.

But a conflict arises while determining the ohmic value of the resistance RGR. If the resistance is too low then when the taps are shorted the short-circuit current would rise to unacceptable levels and if the resistance value is too high then the output voltage would be too low during transition which may cause a jolt when full voltage is restored. Hence, the ohomic value of RGR has to be a compromise between these two extremes.

Figure: 1

Now, coming back to the transition from notch 1 to notch 2, CGR2 closes first then CGR1 opens and then CGR3 closes thereby completing the transition. But here you will note that during the transition the selector arms have not moved. As soon as CGR-3 closes the long selector moves to tap segment 3. (See Fig. 2.)

51 | P a g e

Figure : 2

Fig. 2 describes the first phase of transition to notch 3. As CGR-1 is open, no current is flowing through the long selector hence it can move freely between the contacts without causing arcing. As soon as the long selector arrives at tap segment 3 the tap-changer is ready for transition to notch 3. Transition from notch 2 to notch 3 takes place on lines similar to that of the transition between notches 1 and 2. CGR-2 closes then CGR-3 opens and then CGR-1 closes.

As soon as transition to notch 3 is complete the short selector moves to tap segment 4 hence making the tap-changer ready for transition to notch 4. Again the short selector moves while CGR-3 is open so that there is no danger of arcing. (See Fig. 3.) When the short selector arrives at the tap segment 4, transition to notch 4 occurs on lines similar to that of the transition between notches 1 and 2.

Rest of the notches also undergo transition as per the above description. During regression the exact reverse of the transition sequence described above takes place. Although the mechanical process seems to be cumbersome, it's actually very smooth because the basic design is simple and the mechanism is usually well maintained and lubricated with graphite grease.

Figure : 3

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Figure:4

The efficiency of the tap-changer can be gauged from the fact that it can operate upto a

hundred or more times during a single run of the loco. As per CLW specifications, the tap-changer must be able to complete a full cycle from

first notch to the thirty-second notch in 11-13 seconds and similarly for regression from 32 to 0. As I've mentioned above the tap-changer is very efficient and smooth but even the best

maintained machines sometimes fail. As such in case of failure of any component of the tap-changer it must be ensured that the damage is curtailed as much as possible. For this purpose a series of protective and interlocking relays have been provided and wired in such a way that they can effectively protect the tap-changer and other equipment in the loco. Although detailed circuit descriptions are beyond the scope of this article, I will give a very brief description of the main relays associated with the tap-changer and their place in the larger hierarchy of the locos' complex electrical circuits. However, before proceeding to the relays, two other sub-assemblies of the tap-changer should also be described without which this article would be incomplete-namely: the air-servo motor (SMGR) and the auxiliary cam group switches ASMGR. Air-Servo Motor 'SMGR' :

The SMGR is the motor which drives the mechanism I have described above and it consists of four cylinders which contain pistons driving a common crank-shaft. Depending on the sequence under which compressed air enters the cylinders the motor can run in each direction as required. In turn the entry of the compressed air into the cylinders is governed by valves provided above the motor. These valves are operated by a camshaft which ensures that the valves operate with proper timing and sequence. This camshaft itself is connected to the crank-shaft of the SMGR and is thus self-perpetuating. It only requires a nudge in either direction to start the motor running in that direction. Hence, no complicated external control is required to run the motor. The Crankshaft also has a heavy flywheel at its other end which enables the motor to run smoothly when required. The above mentioned 'nudge' that I have mentioned is provided by two electro-valves placed opposite each other. One valve is for progression and one for regression. These valves are directly controlled by the master controller (MP) and are designated SMGR VE UP and SMGR VE DOWN, respectively.

As the SMGR is driven by air-operated pistons, it has a high inertia. This ensures that its rotation is highly accurate and does not overshoot. This is very important because each

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transition between notches requires only a half turn of the motor which (through the various gears) translates into a 10-degree rotation of one of the selectors and a 90-degree rotation of the CGR camshaft. POH OF TRANSFORMER :

Details of work to be carried out during POH is given as under: General :

First of all remove as much dirt as possible particularly around the transformer tank, radiator protective net, terminal block covers & PRV etc. Open the radiator protective net and blow the dust of transformer & radiator with compressed air. Incoming Tests/ Inspection :

Before carrying out any incoming tests, disconnect following connections. Disconnect roof bushing connection from HT primary cable/ condenser bushing. Disconnect the earth leads from the transformer primary earth bushing terminal

block. Disconnect all the power cable connection from secondary winding side terminal

blocks. Disconnect all the cables from auxiliary windings terminal blocks.

Visual Inspection : Clean the body of the transformer and tightened all the bolts in the body of the

transformer. Check the complete tank for any deformation and crack. Check the oil leakage from transformer tank, radiator, the oil pipes flange joints, conservator, Buchholz device, drain plugs, vent plugs and both side terminal blocks. Check the thread condition of drain plug and oil sample valve, air release vents and

replace all gaskets/washers.

Check the conservator for any bend and damage. Check the under frame oil pipe lines, gate valves, tank etc. for any hitting mark, damage etc. Note all the defects and deficiencies.

Meggering : Check the insulation resistance of windings between:

A. Different winding to earth by 2.5 kV megger. B. Between end frame and core by 1kV Megger.

Continuity Test :

Check the continuity of the following windings with the multimeter: Primary winding across P3 & P4 Secondary windings across a1& a2, a3 & a8 Auxiliary winding I across a11 & a12 Auxiliary winding II across a21 & a22

Transformer Oil Testing : (i) Check the oil characteristics for tests given in table given below. Compare the results with the result recorded earlier on the same oil. Any abrupt change

in the value of the parameters is indicative of the unhealthiness of the transformer. The transformer should be opened for detailed internal inspection for any incipient fault. However, if the flash point falls by 15 degree C from its initial value, replace the oil with new filtered oil without opening the transformer.

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(ii) If the colour of the oil has became dark brown, which is indicative of presence of dissolved copper, change the oil with new filtered oil meeting characteristics.

(iii) For interpretation of results of dissolved gas analysis. (iv) If either of the parameters i.e. flash point, interfacial tension, specific resistance,

total acidity and dielectric dissipation factor are beyond the permissible limits, replace the oil with new filtered oil.

(v) Measure and record the inhibitor content in the oil, if inhibited.

SL No.

Tests Test Methods Permissible Limit Requirement of new filtered Oil

1. Visual inspection As per IS

12463 – 1988

The oil Shall be clear and transparent and free from

suspended mater of sediment

3. Electrical Strength (Breakdown Voltage)

IS: 6792- 72 30 KV

(r.m.s.)(min) 60 KV (r.m.s.)

4. Water

content(PPM) IS: 335 – 1983 35 PPM (Max) 25 PPM (Max)

5. Specific Resistance at 90˚C (Ohm – cm)

IS: 6103 – 71 0.1 x 10¹² Ohm –

cm (Min) 35 x 10¹² Ohm cm ( Min)

6. Total acidity IS : 1448 – 67 0.5 mg KOH / gm(

Max) 0.08 mg KOH /gm

Purification of Transformer Oil :

If transformer is not due for core lifting and other test results are satisfactory, connect the transformer for oil purification. Filtration of EHV grade oil is to be carried out at a vacuum

level of 98% at a temperature of 60 degree C and of inhibited oil at a pressure of 0.15 torcillie at a temperature of 60 degree C. Filtration should continue till such time the oil is completely dried. Check the filtered oil sample for electrical strength and water content and if these parameters are within the limits, the oil is fit for use and if not, repeat filtration till electrical strength and water content are within limits. Internal Inspection :

In order to obtain optimum service life from the EMU transformer, it is suggested that transformer is opened and core is lifted at an interval of 6 to 8 years of service. Core should also be lifted during first POH after commissioning for tightening of the pressure bolts. Following work is to be carried out if transformer is due for internal inspection.

Removing of Active Part (Windings) From Tank Close all the gate valves of transformer and its pipes lines. Drain oil from transformer pipe lines. Disconnect all electrical connections of transformer. Disconnect and remove main bushing. Disconnect all pipe line connections to the transformer. Open all base parts from transformer tank. Provide hydraulic trolley below the transformer tank and lift the transformer by the

trolley. Remove all the foundation bolts fixing transformer to the motor coach.

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Remove the transformer with the help of hydraulic trolley. Bring the transformer in transformer repairing section. Clean thoroughly the transformer body. Drain the transformer oil completely. Remove all the bolts from the transformer tank top covers. Remove all three number inspection covers. Disconnect all windings connections from terminal blocks and also remove the

earthing connection of active part. Lift the active part (windings) with top cover with the help of crane. Place the active part on wooden blocks and remove the top cover by removing its

fixing bolts. Inspection of Active Part (Windings) :

Lower and raise the active part 4 to 5 times in a dry oil bath so as to remove the sludge from the ducts in the core/ windings.

Place the active part (windings) in a large vessel vertically on wooden blocks and hose down with clean dry oil. Do not impinge hot oil jet on the transformer windings.

Check all the core support bolts for any crack at the welded joint and replace them if required.

Check the tightness of yoke bolts by torque wrench. Check the spacers and wedges for proper position and thickness. Check the lead paper insulation for any damage and reinsulated if necessary. Check the distance between the bus bars and yoke. Check the bushing stud and insulator for any damage and replace if necessary. Check the tightness of bus bar leads and also crimping terminal joints. Check the condition of insulating separators. Tighten all pressure bolts until Belleville washers are flattened and then rotate by 1/6

turn in opposite direction. Bake the active part (windings) in oven at a temperature of 60 degree C. Check insulation resistance with 1 kV megger between end frame and core.

Inspection of Fittings Buchholz Relay

Clean the complete assembly with fresh transformer oil. Check the Reed switch on test bench for its healthiness. Check manually the free operation of BUD floats. Check visually the glass indicator for any damage. Check the operation of assembly by allowing the oil flow. Check the pet cock for free operation.

Silica Gel Breather :

Check the silica gel breather visually for any abnormality/ damage. Reactivate silica gel by heating in a shallow pan at a temperature of 150 deg. C to 200

deg. C for two or three hours until the crystals should have regained their original blue tint.

Clean and dry all parts of the breather before filling the container with silica gel. Fill the fresh or reactivated silica gel crystals. Verify that the oil level in the oil cup is correct after reassembly.

Thermostat : Clean the thermostat assembly with petrol. Check the contact closing temperature with the help of thermo-meter. Check visually the presence of transformer oil in thermostat pocket.

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Pressure Relief Valve :

Check the diaphragm visually for healthiness. Check the springs visually for any defect and ensure their tention. Clean the PRV contacts with petrol and check its operation manually. Ensure free movement of PRV plunger manually.

Radiator : Clean the radiator tubes thoroughly by compressed air and high pressure water jet. Check radiator tubes and fins for any damage. Replace both side cover gasket of radiator with new one.

Pipe Lines And Couplings :

Clean all the pipelines and coupling thoroughly. Check all the pipelines, flexible couplings for any damage, hitting marks etc. Check all the supporting clamps and brackets of the pipelines for any damage, welding crack etc. Paint all the pipelines with grey paint.

Conservator : Clean conservator and glass indicator thoroughly. Check the conservator for any damage, intactness of indicator glass and condition of

glass. Check flexible coupling below conservator for any damage, oil leakage etc. Paint the conservator with grey paint.

Main Bushing : Clean the roof bushing insulator, condenser sleeve and transformer bushing thoroughly. Check visually roof bushing porcelain insulator for any crack, flash mark etc. Check condenser sleeve for any damage, crack etc.

Remove oil from the condenser bushing if provided. Check and record tan- delta of the bushings (without oil at 1,2 and 5 kV). If the value of the tan delta is greater than 3%, replace the bushing. Check flange to flange distance in the condenser bushing, it should be of 2200± 5 mm. If this gap is found to be less. Final Fitment of Transformer on Motor Coach : Fit the transformer on motor coach with the help of hydraulic trolley. Fit all the fitting such as Buchholz device, main bushing, conservator, breather etc. Connect all the pipe lines, flexible couplings and pipe lines support. Connect all electrical connection, earthing leads etc. If transformer oil has been replaced due to any reason, replace the oil of choke tank also. Fill the transformer oil up to proper level. Ensure open condition of all gate valves. Connect the transformer to the oil purification plant for purification of transformer oil and carry out purification as described under section 2.4.4.

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Check the transformer, conservator, Buchholz device, pipe lines, couplings, gate valves, radiator etc. visually for any defect or deficiency. Final Checking : Check visually for any oil leakage from any point, coupling, joints etc. Ensure the open condition of all the gate valves. Check and ensure oil level in conservator, it should be minimum 15 degree C mark. Release air from vent plugs. Check the function of Buchholz relay. Ensure connection of thermostat and oil in TT pocket. Ensure operation of PRV plunger and its connections. Check the transformer fuses. Provide all terminal block covers

Shop No. – 14 is Rewinding shop of Kanchrapara Railway Workshop, Where both Periodic Overhauling (POH) and Rewinding of Traction Motor armature, TFP (EMU), Field Coil, Smoothing Reactor are done.

This Shop Has a Five Section : (ix) Heavy Armature Section (x) Core and Commutator Section (xi) Coil Section

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(xii) Transformer Section (xiii) ABFCR & SL (Armature Bearing and Field Coil Reclamation Section and

Smoothing Reactor[SL – 30])

Mr. Priyotosh Nandi SSE is the incharge of Shop No.-14 and Others SSE and JE are as follows:

Heavy Armature Section:

Mr. Pulakmoy Mondal (SSE) Mr. Shekhar Mitra (SSE) Mr. Bikramjit Nath (JE) Mr. Sanjay Ghosh (JE) Mr. Tapas Sarkar (JE) Mr. Amit Kr. Sharma (JE) Mr. Deepak Mandal (JE) Mr. Sunil Kr. Topno (JE)

Core and Commutator Section:

Mr. Parthapratim Mondal (JE)

Coil Sectio : Mr. Jayanta Das (SSE) Srmt. Baishakhi Paul (JE) Mr. Amaresh Poddar (JE)

Transformer Section:

Mr. N.K. Meena (SSE) Mr. Sanjoy Nath (JE)

ABFCR & SL Section :

Mr. Chandan Patra (JE)

Heavy Armature

POH OF TRACTION ARMATURES AFTER INCOMING INVESTIGATION Types- HS15250A

TAO-659 EMU(4601AZ)

Micro Ohm Meter(MOM) Test & Surge Comparison Test(SCT): During MOM test- For EMU armature difference between minimum & maximum reading should be 0.10. For Loco armature difference between minimum & maximum reading should be 0.06. During SCT test check whether there is inter turn short fault between conductors of loop

coils or coil earth fault.

If MOM & SCT Test are normal: Cleaning of armature by Thinner-205 Baking of armature at 120 degree centigrade temperature for 12 hrs .

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Removal of dust by blower Again cleaning of armature PTFE ring fitting according to its condition

After Cleaning : Application of Anti Tracking Varnish- Bectol Red for EMU & TAO-659 TVA-1410 for HS-15250A

After application of Anti Tracking Varnish: Commutator turning Mica under cutting Dissipation Factor (DF) test at 1 kV & value of TAN delta should be within 2% Despatch of armature to proper shops & sheds for fitting into traction motor frame.

Technical Data Of Traction Motor Armature

Type Of Armature HS-1520A TAO-659 4601AZ

No OF Arm/Loco/Unit 6 6 4

Kilo Watt 630 585 167

Volt 750 750 535

Amps 900 840 340

Speed 895 1060 1260

Weight Of Armature 980 850 518

Class Of Insulation 200 H H

No Of Pole 6 6 4

No Of Armature Slot 57 69 46

No Of Armature Coil 57 69 46

Armature Coil Pitch 1-10 1-12 1-12

No Of Equalizer Coil 2x57 6x23 46/92

Equalizer Coil Pitch On Commutator Segment 1-96 1-93 1-116

Total Weight Of Copper In Arm coil 94Kg 67Kg 55.4kg

Total Weight Of Copper In Equ. coil 2Kg 4Kg 1kg/2kg

Type Of Armature HS-1520A TAO-659 4601AZ

Resistance Of Armature In Ohm 0.01283 Ω At 115°c

0.0151Ω At 110°c

0.0185Ω

Commutator Dia.(New) 400mm 380mm 325mm

Commutator Dia.(Old) 380mm 364mm 304.8mm

No Of Commutator Segment 285 276 230

Comm. Tightening System Spring Lock Ring Bolts Bolts

Core Length Of The Armature 480mm 390mm 260.4mm

Core Diameter 500mm 500mm 45±0.2mm

Shaft Length 1306/1336mm 1130mm 975±0.5mm

Bearing Seat Dia.(PE) 150.043 to 150.068 140.05 to 140.07

130.035 to 130.055

Bearing Seat Dia.(CE) 120.037 to 120.059 90.025 to 90.045

90.025 to 90.045

ARMATURE REWINDING

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Insulation Resistance Test:-

Outer V core cleaning, commutator cleaning, short the commutator segment with the above strand of copper wire and take IR value of armature.

Tools, Equipment & Material Required:-500V Megger, brush, sand paper & strand of bare copper.

MOM (mΩ) Test:-

Under cut the commutator, clean commutators, brush and sand paper. Mark any one of the commutators segment by chalk. Select suitable range on the digital Micro Ohmmeter and start measuring the bar resistance starting from the segment pairs 1-2. Warm up the MOM machine fully before taking the reading. The probes should be kept at constant distance from the riser face for all measurement. Test should be carried out at ambient temperature. Complete the test at a stretch not exceeding 2-3hrs.

Standard Testing Parameters:- Tools, Equipment & Material Required:-

Digital micro ohmmeter (min. accuracy ± 0.1%), under cutter, sand paper, knife, brush & chalk

For EMU Armature:- Difference between minimum to maximum reading will be 0.10 mΩ For LOCO Armature:-Difference between minimum to maximum reasing will be 0.06 mΩ.

Surge Comparison Test:-

Clean the commutator properly. Adjust input voltage of SCT machine (230V) operating voltage stabilizer. Set the test voltage at 0 position. Set the test selector switch at armature test mode position (0-1KV). Set the VOLTS/DIVISION. switch. Put the power switch at on position. Connect the armature with SCT machine probe set all the other controls. Press the surge Test Switch & increase the test voltage up to 1KV. Now test the armature operating surge test switch by touching the probe lead at the commutator segment 1-5.

Standard Testing Parameters:- Follow the oscilloscope display & compare with the standard curve for individual type of

armature. Generally a diminishing sinusoidal curve is obtained for a non-faulty commutators, other wise the commutator segment is faulty.

Tools, Equipment & Material Required :- Under cutter, Sand Paper, Tester, Knife, Brush &

chalk. The rewinding which takes near about a month is done in the following procedure:-

Commutator Attention & core cleaning:- the old commutators is tested and checked if it can be reused or not. If it can be reused windings are kept intact and is send for core cleaning

If faulty the windings are stripped and are rewinded again. Deck insulation is done and is sent for baking. Equalizing coil is mounted on the deck insulation and is sent for baking (except for Hitachi). Equalizing coil is pressing is done High voltage test is done to see if the coil can withstand the voltage for a few second. Insulation over equalizing coil Baking I done for 8-10hrs at 140-180oC. Power coil mounting is done Piece setting, i.e. small piece of copper is inserted between the leads of ending to make the

structure compact.

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Baking I done for 8-10hrs at 140-180oC.

Fig:Before pressing of power coil

Power coil pressing is done High voltage test is done for limited time Glass fibre wedge (Epoxi) is inserted to make the armature compact. Excess lead cutting and riser facing. Tungsten Inert Gas (TIG) wielding is done to weld the lead end properly. Here inert gas

used is argon which cuts out the oxygen and tungsten is the electrode used. Baking I done for 8-10hrs at 140-180oC. Poly glass banding.

Fig:Armature

Final MOM, Surge Comparison Test, Dynamic balancing is done.

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High voltage test and tan delta test is done. Tan delta test is the dielectric test of the insulation between the rotor Shaft and armature. Generally the capacitance is tested.

Commutator turning. TRANSFORMER WINDING:-

In this section the rewinding of transformer winding is done. The transformer is rewinded in the following procedure:-

On receiving of transformer the following incoming test to be done:- IR test Ratio MOM mA current test Visual Inspection after oil draining & striping of active part from the tank Cleaning until sludge removed. Coil striped out from the limb & checking to be done Core barrel lifting. Core bolt & core tube checking to be done & after filling IR(Megger)

value to be taken. Barrel fitting to be done after proper insulation. Coil mounting with proper Separator & lock. Nomex separator to be used in between primary & secondary coil. Intake 25KV primary coil to be checked properly. Secondary coil bus bar and load connection be done with proper silver bracing Condition of lamination to be checked properly & mounting to be done. Channel fitting with proper insulation to be done. Connection to be made and all testing to be done (IR, Ratio, MOM, mA current). Active part to be boxed up into the tank with proper insulation. Boxing of transformer to be done properly. Filling of filterised oil after BDV testing of oil. Final Testing IR test, Ratio MOM Normal frequency High Frequency Dielectric test Painting of transformer Dispatch

COMMUTATOR

The is of arch bound construction built-up with hard drawn silver bearings copper segments which are insulated with micanite and are assembled with modulated mica insulation between steel V-rings.

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The function of the commutator in d.c. motor is to reverse the direction of current in each conductor as it passes from one pole to another, it helps to develop a continuous and unidirectional torque.

Work Instruction for New comutator Fitment: For HS 15250A: Heat the steel parts of the armature, then opened the steel parts with the help of puller.

Clean armature shaft and inside the steel parts property. Put the commutator in baking oven for 12 hour. Heat the steel parts of the commutator and

then insert the armature after proper centering. Take bar to bar and IR test, After cooling the commutator.

For TAO -659 : Clean the steel part properly. Set mica in a “V” Cone shell and then the commutator . Center

the commutator properly. Set mica “V” cone outer steel cone. Tight 20 Number fixing bolt with washer.

Put the armature in a baking oven for 12 hour. Then tight all the fixing. Bolt finnaly with the torqe range at 28 Kgm torque.

Take the bar to bar, IR test after colling the commutator. For 4601 – AZ: Heat the steel part of the armature and then open the steel part with puller. Clean the

armature shaft and inside the steam part properly. Heat the steel part of the cpommutator. The insert the armature shaft after proper centering. Take bar to bar and IR test after cooling the commutator.

Re - Surfacing/ Turning of commutator: Check and clean both side of the shaft centre. Mount the armature on lathe machine by EOT crane. Check the Shaft ovality. Adjust job speed and feed for better surface finish. Primary turning and groove cutting. Final turning. Measurement of commutator diameter.

COIL SECTION

This section deals with manufacturing of power coil and equalizer coil of TAO-659, EMU (4601AZ) and HITACHI (HS15250A) in a traction motor armature according to the

requirements. Incoming armature from shead or shop it investigated by three step (i) Visual (ii) Mechanical and (iii) Electrical.

Fig: TAO Equalizing Coil

The procedure of coil formation is as follows: Cutting of the Cu conductor to the required length according to the various requirements of

the motor.

requirements. Incoming armature from shead or shop it investigated by three step (i) Visual (ii)

Fig: TAO Power Coil

The procedure of coil formation is as follows:- Cutting of the Cu conductor to the required length according to the various requirements of

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requirements. Incoming armature from shead or shop it investigated by three step (i) Visual (ii)

Power Coil

Cutting of the Cu conductor to the required length according to the various requirements of

Fig: Conductors are cut to their required length

5 conductor are cut to form a coil(Hitachi/BHEL) and 4 conductors are cut to form a coil(TAO). V Bending of coils

Fig :HITACHI Evolute formation of Coil.

Conductors are cut to their required length

5 conductor are cut to form a coil(Hitachi/BHEL) and 4 conductors are cut to form a coil(TAO).

Fig :HITACHI Evolute formation of Coil.

Fig : Coil formed by Zig

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5 conductor are cut to form a coil(Hitachi/BHEL) and 4 conductors are cut to form a coil(TAO).

Lead cutting, i.e. the conductors are equally cut. Lead buffing, i.e. removing the insulation covering Lead flattening Lead annealing Reshaping Tapping Inter turn testing and ground testing

Coil testing Schedule:-

Serial No.

Type

1. BHEL

(4601AZ)

2. TAO(659)

3. Hitachi

(HS15250A)

WORK INSTRUCTION FOR MANUFECTURING TRACTION MOTOR ARMETURE COIL HITACHI COIL SHAPING : (i) Cut the conductor

(1)1700mm,(2)1690mm,(3)1675mm,(4)1665mm,and (5)1650mm respectively.(ii) Straighten the irregular portion of conductor by mallet and bunch the five conductors by

cotton tape as per order of conductor length.(iii) Cut excess length of conductor by shearing machine of sizes

(1)1691mm,(2)1682mm,(3)1666mm,(4)1654mm,and (5)1642mm.(iv) Cut the separator of leatheroid paper of dimension of 0.5x75x7mm.(v) Fix the bunched conductor in “U” bending machine.(vi) Fix the highest length conductor in the

length in the next slot at the middle of conductor near to pivot.(vii) Place four nos. separators in between conductors. conductor should be “U” bend by

operating by “U” bending m/c(viii) Mark as bottom arm before d

Fig: BHEL Coils

cutting, i.e. the conductors are equally cut. Lead buffing, i.e. removing the insulation covering

Inter turn testing and ground testing

Type Ground Insulation

(HV in KV) Inter turn (HV in KV)

BHEL (4601AZ)

7.5KV/15 Sec 2KV/15 Sec

TAO (659)

8KV/15 Sec 2KV/15 Sec

Hitachi (HS15250A)

10KV/15 Sec 2KV/15 Sec

WORK INSTRUCTION FOR MANUFECTURING TRACTION MOTOR ARMETURE COIL

Cut the conductor according to specified length of sizes (1)1700mm,(2)1690mm,(3)1675mm,(4)1665mm,and (5)1650mm respectively.Straighten the irregular portion of conductor by mallet and bunch the five conductors by cotton tape as per order of conductor length.

gth of conductor by shearing machine of sizes (1)1691mm,(2)1682mm,(3)1666mm,(4)1654mm,and (5)1642mm. Cut the separator of leatheroid paper of dimension of 0.5x75x7mm. Fix the bunched conductor in “U” bending machine. Fix the highest length conductor in the first slot and then one after another according to length in the next slot at the middle of conductor near to pivot. Place four nos. separators in between conductors. conductor should be “U” bend by operating by “U” bending m/c Mark as bottom arm before dismantling of bunched conductor fixed portions.

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WORK INSTRUCTION FOR MANUFECTURING TRACTION MOTOR ARMETURE COIL

according to specified length of sizes (1)1700mm,(2)1690mm,(3)1675mm,(4)1665mm,and (5)1650mm respectively. Straighten the irregular portion of conductor by mallet and bunch the five conductors by

gth of conductor by shearing machine of sizes

first slot and then one after another according to

Place four nos. separators in between conductors. conductor should be “U” bend by

ismantling of bunched conductor fixed portions.

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(ix) Removes 10 nos. lead kapton insulation by buffing m/c at least 40mm length. (x) Cut conex spiral tube should 45mm,35mm,32mm sizes. (xi) Insert 45mm,spirl tube 2nd 4th conductor top and bottom side and 35mm spiral tube 3rd

conductor of top side and 32mm spiral tube in the 3rd conductor of bottom side. (xii) Step down the conductor by step down m/c as per instruction.

1) Central conductor top & bottom inside. 2) Conductor nos.2nd, 3rd, & 4th top out side & bottom inside. 3) 5th conductor top & bottom outside.

(xiii) Flat 10 nos. lead by 75 ton press machine as per dimension 38x15x(1.35-1.4)mm. (xiv) Remove burr of leads by flat file. (xv) Place leatheroid separators in between conductor and bunch the conductor by cello

tape. (xvi) Bend the 10 nos. leads by lead bending machine as under mentioned:- (a)take half circle’s left side as bottom and left side as top. (b)place coil bottom side in the half circle’s bottom side & operate from right side to left side

directly. (xvii) Reverse the coil and place in the ½ circle’s top side and bend from right side to left

side. (xviii) Twist evolute’s portion of conductors by twister jig. (xix) Place the conductor in the shaping jig & from the coil. (xx) Dress the leads as per order-top arm: 1, 3, 5, 2, 4 & bottom arm: 5, 3, 1, 4, 2

respectively. (xxi) Remove the coil from jig & tie four corners of coil by cello tape. (xxii) Send the ready coils for insulation.

PROCEDURE FOR INSULATION:

(i) Prepare solution by mixing methyl alcohol & P200 as per ratio 50:1. (ii) Dip EGT tap sizes 0.07x13mm and EGT tape 0.1x25mm into p-200 solution for

10minutes. Lift the above tapes from solution and kept it for air dry for 30 minutes. Keep this tape in polythene bag.

(iii) Separate conductor from bunching. (iv) Clean the conductor by soft cloth (v) Check the conductor visually for any damage/abrasion part were cut or scratch mark. (vi) Repair damaged portion by kapton tape 0.065x12mm.long scratches cut kapton tape

size 0.065x12mm in required length and place over scratch portion flat wise to avoid dimensional problem in finished coil.

(vii) Four corners of the 2nd and 4th conductors are to be tapped by one layer ½ lap kapton tepe size (0.065x12mm) up to 15mm each side.

(viii) Checking of tube position in lead side of each conductor and if required shift the tube in position.

(ix) Bunch the five nos. conductor together and bind with kapton tape size (0.065x12mm) in the two portion in lead side (tapping beginning from end of tube).

(x) Setting of coil by malleting lightly with leather mal (xi) let and bind with kapton tape (size 0.065x12mm) in four position in straight(slot)

portion.

TESTING: Offer for inter turn test It test at 2kv for 15sec Slot portion tapping:

2 layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size (0.065x12mm)

1 layer ½ lap tapping with 4 FTNA (0.038x 25mm) sealed with

(0.065x12mm) One layer edge to edge tapping with EGT tape size (0.1x25mm)sealed with kapton

(0.065x12mm) Lead size and opposite side to lead tapping one layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size

(0.065x12mm) 1 layer ½ lap tapping with 4FTNA(0.038x19mm)/ 4 FTNA (0.038x 25mm) sealed with

kapton tape size (0.065x12m One layer 10% tapping with EGT tape size (0.1x25mm)sealed with kapton size

(0.065x12mm) Check visually and check correct dimension by GO/NO Offer for inspection. Test H.V. the coil by 10kv in 15sec. Keep good coil on dust tree table. Send to heavy armature coil godown for keeping.

Manufacturing of traction motor HS COIL SHAPING :

(i) Cut the conductor size 542mm.(ii) Removed end insulation 50mm in both end by lead buffing machine.(iii) Loop forming by loop forming machine.(iv) Conductor(even length)(v) Conductor (odd length)(vi) Step down at lead end by step

size (A&B) conductor A (even length) toplength) top 174mm; bottom 154mm.

(vii) Take A&B conductor and bunched together.(viii) Place the bunched conductor in a shaping jig and from t(ix) Sent for insulation.

Tapping :

(i) Clean the conductor by soft clout.(ii) Repair damage portion by kapton tape, size

2 layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size

1 layer ½ lap tapping with 4 FTNA (0.038x 25mm) sealed with

One layer edge to edge tapping with EGT tape size (0.1x25mm)sealed with kapton

Lead size and opposite side to lead tapping one layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size

1 layer ½ lap tapping with 4FTNA(0.038x19mm)/ 4 FTNA (0.038x 25mm) sealed with kapton tape size (0.065x12mm) One layer 10% tapping with EGT tape size (0.1x25mm)sealed with kapton size

Check visually and check correct dimension by GO/NO-GO gauge.

Test H.V. the coil by 10kv in 15sec. Keep good coil on dust tree table.

eavy armature coil godown for keeping.

Fig : Ready Hitachi Power Coil

Manufacturing of traction motor HS-15250A Equalizer coil

Cut the conductor size 542mm. Removed end insulation 50mm in both end by lead buffing machine.Loop forming by loop forming machine. Conductor(even length)-268mm with a bunch of conductors after straightening.Conductor (odd length)-278mm with a bunch of conductors after straightening.Step down at lead end by step down machine. take a bunch of conductors of each

size (A&B) conductor A (even length) top-164mm; bottom -166mm conductor B(odd length) top 174mm; bottom 154mm.

Take A&B conductor and bunched together. Place the bunched conductor in a shaping jig and from the coil.

Clean the conductor by soft clout. Repair damage portion by kapton tape, size – x0.065.mm.

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2 layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size

1 layer ½ lap tapping with 4 FTNA (0.038x 25mm) sealed with kapton tape size

One layer edge to edge tapping with EGT tape size (0.1x25mm)sealed with kapton size

one layer ½ lap tapping with KUATCZ(0.1x25mm) scaled with kapton tape size

1 layer ½ lap tapping with 4FTNA(0.038x19mm)/ 4 FTNA (0.038x 25mm) sealed with

One layer 10% tapping with EGT tape size (0.1x25mm)sealed with kapton size

Removed end insulation 50mm in both end by lead buffing machine.

268mm with a bunch of conductors after straightening. 278mm with a bunch of conductors after straightening.

down machine. take a bunch of conductors of each 166mm conductor B(odd

(iii) Re-in force both leads and evouate portion by kapton tape layer.

(iv) Again ½ lap one layer by glass tape 13x0.08mm (dry condition) in lead portion. (v) Bunch of conductor by kapton tape (10x0.065mm).(vi) Tapping ½ lap one layer by 4FTNA (0.038x19mm).(vii) Tapping done by EGT tape (13x0.08mm) ½ lap one layer.(viii) Inspect the coil and measu(ix) Visual checking. (x) Testing : inter turn test by 2KV in 15 Sec.(xi) Ready coil sent to heavy armature coil godown for rewinding.

MANUFACTURING OF TAO-659 TRACTION MOTOR POWER COIL COIL SHAPING :

(i) Cut conductor of size 1520mm(ii) Strengthen the irregular conductor by mallet.(iii) Cut notch 02 nos. of conductors of each coil by notch cutting machine and remove

burrs after notch cutting.(iv) From loop of 04 nos. conductors of coil by loop forming machine

cutting and another two numbers ordinary.(v) Bunch four numbers conductor together keeping two numbers notch cutting inside

and two notch ordinary conductors outside.(vi) From the coil by coil forming jig keeping long part as top in right side(vii) Cut excess conductors at lead end after marking.(viii) Remove lead end insulation at least 28mm by lead buffing machine.(ix) Flat 04 nos. conductor lead by 40 ton hydraulic press machine size of lead 27mmx(1.15

to 1.2)mm. (x) Dress all 08 nos. lead by f(xi) Anneal 08 nos. lead by annealing machine.(xii) Clean the 08 nos. leads by steel wool.(xiii) Re-shape the coil by mallet and coil forming jig.(xiv) Sent the ready coil for insulation.

PROCEDURE FOR EART INSULATION:

(i) Prepare DC-994 varnish by (ii) Dip the glass tape size 19x82

breaking the glass tape till air bubble coming out.

in force both leads and evouate portion by kapton tape (10x0.065mm)

one layer by glass tape 13x0.08mm (dry condition) in lead portion.

Bunch of conductor by kapton tape (10x0.065mm). Tapping ½ lap one layer by 4FTNA (0.038x19mm). Tapping done by EGT tape (13x0.08mm) ½ lap one layer. Inspect the coil and measure by Go/NO GO Gauge.

inter turn test by 2KV in 15 Sec. Ready coil sent to heavy armature coil godown for rewinding.

Fig : Ready Hitachi Equalizer Coil

659 TRACTION MOTOR POWER COIL

Cut conductor of size 1520mm Strengthen the irregular conductor by mallet. Cut notch 02 nos. of conductors of each coil by notch cutting machine and remove burrs after notch cutting. From loop of 04 nos. conductors of coil by loop forming machine, two of them notch cutting and another two numbers ordinary. Bunch four numbers conductor together keeping two numbers notch cutting inside and two notch ordinary conductors outside. From the coil by coil forming jig keeping long part as top in right sideCut excess conductors at lead end after marking. Remove lead end insulation at least 28mm by lead buffing machine. Flat 04 nos. conductor lead by 40 ton hydraulic press machine size of lead 27mmx(1.15

Dress all 08 nos. lead by file and lead buffing machine. Anneal 08 nos. lead by annealing machine. Clean the 08 nos. leads by steel wool.

shape the coil by mallet and coil forming jig. Sent the ready coil for insulation.

PROCEDURE FOR EART INSULATION: 994 varnish by mixing catalyst 15 as per ratio 400:3.

Dip the glass tape size 19x82-0.08mm and 13x0.08mm into varnish solution after breaking the glass tape till air bubble coming out.

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(10x0.065mm) ½ lap one

one layer by glass tape 13x0.08mm (dry condition) in lead portion.

Cut notch 02 nos. of conductors of each coil by notch cutting machine and remove

, two of them notch

Bunch four numbers conductor together keeping two numbers notch cutting inside

From the coil by coil forming jig keeping long part as top in right side from evaluated.

Flat 04 nos. conductor lead by 40 ton hydraulic press machine size of lead 27mmx(1.15

0.08mm and 13x0.08mm into varnish solution after

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(iii) Expose the glass tape in air for curing. (iv) Check the formed coil visually any defect is present or not. (v) Clean each conductor of coil by soft cloth.

INDIVIDUAL CONDUCTOR TAPPING :

Repair insulation cut portion and damaged portion by kapton tape size 0.065x12mm. Leads tapping – a)one layer ½ over lap up to 50mm by kapton tape size 0.065x12mmb)one

layer1/2 over lap upto 50mm.by nomex tape size (2mill x 10.c) one layer 1/2 over layer up to 50mm by impregnated glass tape size 13x0.08mm

Evaluate – 2 layer ½ over lap upto 70mm. by kapton tape size 0.065x12mm. Corners – one layer ½ over lap upto 30mm of wall corner by kapton tape staggering by

kapton tape size – 0.065x12mm.

EARTH INSULATION : Slot portion – a) one layer ½ over lap by KUATCZ size 0.1x25mm, b) one layer SPS by

KUATCZ size 0.1x25mm, c) one layer ½ over lap by KUATACZ size- 0.1x25mm. Over hung- a) 2 layer ½ over lap by KUATCZ size 0.1x25mm.on top over hung. b)one layer

½ over lap by KUATCZ sixe 0.1x25mm. on bottom over hung. Overall – a)one layer edge to edge by impregnated glass tape size 0.08x19 on slot portion,

b)one layer ½ over lap by impregnated glass tape size 0.08x19on over hung portion. Note – seal the end of each tapping by kapton tape size-0.065x12mm. Inspect the coil and measure by GO/NO GO gauge. Test – a) interturn test by 2KV in15 Sec. b)earth insulation test by 8KV in 15 Sec. Ready coil sent to heavy armature godown for rewinding.

Fig : Ready TAO Power Coil

EQUALIZER COIL SHAPING : Cut conductors size – 540mm. Strengthen irregular conductor by mallet. Cut notch of 06 Nos. conductor by notch cutting machine. Remove burrs after notch cutting by file. Remove of end insulation of 06 Nos. conductors about 50mm. length by lead buffing

machine. From loop a bunch of six numbers conductors by loop forming machine. From coil by coil forming jig and bunch them together. Sent for insulation.

INSULATION PROGRAME FOR EQUILIZER COIL :

(i) Individual conductor tapping

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(ii) Check each conductor visually and clean by shop floor. (iii) Repair insulation cut portion and damaged portion of each conductor by kapton tape

size-0.065x10mm. (iv) Tape the 1st , 3rd ,5th , and 6th conductors one layer ½ over lap by nomex tape size-2mil x

10mm, from one lead end to another lead end. (v) Re-inforce of all lead of 6 nos. conductors by impregnated glass tape size 0.08x13mm

one layer ½ over lap. (vi) Re-inforce of all leads of 06 nos. conduc5tors by kapton tape size 0.065x10mm.one layer

½ over lap. (vii) Bunch 06 nos. conductors together by kapton 9 nos. tape size 0.065x10mm. (viii) Do the final tapping by impregnated glass tape size 0.08x13mm.from one lead end to

another lead end and leaving evaluate portion only. (ix) Inspection the coil visually. (x) Test- i) interturn test by 2KV in 15 Sec (xi) Ready coil sent to heavy armature godown for rewinding.

Fig : TAO Equalizer

MANUFACTURE OF BHEL 4601AZ ARMATURE POWER COIL :

(i) Coil shaping (ii) Cut the conductor size 1390mm (iii) Strengthen irregular conductor by mallet (iv) Bunch 05 notch conductor by cotton tape (v) From v-loop by loop forming jig & mark bottom side 665 mm (vi) Bent v-looped in bending jig (vii) Shape the coil by coil forming jig be ensure that the long as top arm & fix in right side of

jig.(from evaluate end) (viii) Cut excess conductor of lead by cutting device length of top lead 38.6mm.& bottom lead

35.4mm (ix) Remove lead end insulation about 35mm by lead buffing machine (x) Flat 10 nos. lead by 40 to hydraulic press machine, lead thickness for 80% 1.15mm to

1.2mm.& 40% 1.6 to 1.65 mm. (xi) Anneal all leads of 40% power coil by lead annealing machine. (xii) Clean the lead portion by steel wool after annealing . (xiii) Re-shape the coil by mallet & shaping jig. (xiv) Sent the shaped coil for insulation.

INSULATION PROGRAMME OF 4601AZ POWER COIL :

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(i) Prepare DC-994 varnish solution by mixing catalyst 15 as per ratio 400:3. (ii) Dip the glass tape size 0.08mmx19mm and 13x0.08mm into varnish solution after

breaking the glass tape till air bubble coming out. (iii) Expose the glass tape in air for curing. (iv) Check the formed coil visually any defect is present or not. (v) Clean each conductor of coil by soft cloth.

INDIVIDUAL CONDUCTOR TAPPING :

(i) Repair insulation cut portion or damage portion by kapton tape size 0.065x12mm (ii) Lead tapping of 5 conductor a)one layer ½ over lap by kapton tape size 0.065x12mm.upto

30mm. (iii) Evaluate tapping- one layer ½ over lap by kapton tape size 0.065x12mm of each

conductor. (iv) Corner tapping- one layer ½ over lap by kapton tape size 0.065x12mm of four coners of

the 1st ,3rd and 5th conductors upto 25mm length. (v) Bunch 5 nos. conductors together and bind with kapton tape size 0.065x12mm.tightly (vi) Wrapping with cotton tape sized 19mmx0.1mm wall through the common 1st moulding. (vii) 1st moulding – moulding the coil by hydraulic press machine accord to the schedule

horizontally – 3550Kg/Cm² & vertically 1880Kg/Cm² for 170°C in 1 hr 10 min. & afterwards water cooling for 20min.

(viii) Remove cotton tape. (ix) Over hung-one layer ½ over lap by glass mica tape size 0.08x15mm. on wall over hung

portion (x) Corner- one layer ½ over lap by kapton size 0.065x15mm. for all four corner. (xi) Cut nomex mica sheet size 285x0.08x160mm. (xii) Put DC-994 varnish solution coating on the nomex mica sheet. (xiii) Vanish solution coating on the nomex mica sheet. (xiv) Wrap the previous prepare nomex sheet on the slot portion by 3 ½ layer. (xv) Do final tapping by impregnated glass type size 0.08x19mm,one layer ½ over lap on over

hung and one layer edge to edge on slot portion sealed with kapton tape size 0.065x15mm.

(xvi) Baking schedule- a) bake the coil for 1hr 10min. & 180°C sent for varnish, b)varnish the coil by DC994 varnish solution, c) bake the coil 6hr for 180°c sent

(xvii) Second moulding – mould the curing coil as per moulding schedule horizontally 3550Kg/Cm².vertically 1880Kg/Cm² at 170°c sent tem. Duration 10min.colling 20min.

(xviii) Inspect the coil and measure by GO/NOT GO gauge

TESTING :

(i) Interturn test by 2KV for 15 Sec. (ii) Earth insulation test by 7.5KV in 15 Sec. (iii) Sent ready coil to heavy armature coil godown for rewinding (iv) Shaping of equalizer coil of 4601AZ traction motor (v) Cut the conductor as per length 40% 640mm.& 80% 660mm. (vi) Remove end insulation of the conductor about 45mm.to 50mm. by lead buffing machine. (vii) From loop by loop forming jig. (viii) Shape coil by coli shaping jig. (ix) Sent for tapping

TAPPING SEHEDULE OF EQALIZER COIL :

(i) Clean the conductor by soft cloth.(ii) Repair insulation cut portion and damage portion by kapton size 0.065x10mm.(iii) Reinforce both end and evaluate portion by

over lap. (iv) Does final tape by glass tape size 0.08x13mm.one layer half over lap.(v) Do another coil final tape by nomex tape size to mil x 10mm one layer half over lap(vi) Reinforce both end and evaluate by kapton tape si(vii) Ready coil sent to heavy armature godown for rewinding.

Fig: BHEL Power Coil.

TAPPING SEHEDULE OF EQALIZER COIL : Clean the conductor by soft cloth. Repair insulation cut portion and damage portion by kapton size 0.065x10mm.Reinforce both end and evaluate portion by kapton tape size 0.065x10mm.one layer half

Does final tape by glass tape size 0.08x13mm.one layer half over lap. Do another coil final tape by nomex tape size to mil x 10mm one layer half over lapReinforce both end and evaluate by kapton tape size 0.065x10mm one layer half over lap.

Ready coil sent to heavy armature godown for rewinding.

Fig : BHEL Equalizer

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Repair insulation cut portion and damage portion by kapton size 0.065x10mm. kapton tape size 0.065x10mm.one layer half

Do another coil final tape by nomex tape size to mil x 10mm one layer half over lap ze 0.065x10mm one layer half over lap.

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Smoothing Reactor

Smoothing reactors are used in order to reduce harmonic current & transient over current (ripple) in DC system. This reactor is necessary in order to smooth the direct current to reduce loss & improve system performance.

DC system often require a smoothing of DC wave shape to reduce losses & improve system performance. Series reactors inserted in DC system after this response & additionally operate as current limiting device in the event of a fault. Smoothing reactors are widely used in HVDC system.

Fig : Smoothing Reactor

Repair & over hauling of Smoothing Reactor : SCOPE :- Smoothing reactor type-sl-30 RESPONSIBILITY:- SE in charge of heavy armature section.

WORKING PROCEDURE:-

(i) Clean the SL-30 with the help of compressed air. (ii) Place SL-30 horizontally on the ground with the help of crane. (iii) De-brazing the joint outer & inner coil with the help of ges. (iv) Remove ,crossbar & support plate. (v) Place both limb of SL-30 on working stand. (vi) Remove wedges & spacers from both coils & inner coils. (vii) Remove shoe from the inner coil with the help of pillar crane from both limb. (viii) Remove inner coil from outer coil with the help of pillar crane of both limb. (ix) Check the insulation of outer coil, inner coil & shoe.

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Shoe re-insulation

(i) Remove the old insulation of the shoe & clean it properly. (ii) Re-insulate the shoe with the help of GMGS sheet, glass cloth GMS tape & finally glass

tape. (iii) Baked shoe in baking oven at 130°C for 12hr. & apply DC-997 varnish & again bake. (iv) After baking apply anti-braking varnish (Bectrol Red).

Outer coil repair & insulation (i) Remove other coil top & bottom insulation with knife & mallet & re-insulation (ii) Check inter turn insulation (iii) Provide inter layer insulation with nomex and varnish & replace with new separator. (iv) Baked the coil in baking oven. (v) Apply DC-997 varnish followed by baking (vi) Apply anti tracking varnish.

INNER COIL REPAIR

(i) Inner coils top &bottom varnish removed. (ii) Inter layer insulation provide with nomex paper & varnish & replace with new separator. (iii) Put the coil in baking oven. (iv) Varnish the coil with DC-997 varnish & again baked followed by apply anti tracking

varnish. ASSEMBLY

(i) Coils to be taken out from the baking oven and placed on working table. (ii) Keeping of core shoes inner coils & other coils done with new wedges. (iii) Clamp is fixed wit connection lead & cross bars fitted with stud assembly. (iv) Testing of SL-30 IR, HV SCT record in resister no. (v) Dispatch.