Summer Trainingat

Electric Loco Shed, Tughlakabad, New Delhi

25 May 2016-22 June 2016

University College of Engineering, Rajasthan Technical University, Kota

Website: www.rtu.ac.in , Electrical Engineering DepartmentSession 2015-16

Project Report on Summer Training at Electric Loco Shed

WCR, Tughlakabad, New DelhiSubmitted By:

Prabjeet Singh (13EUCEE060)

BACHELOR OF TECHNOLOGY

ELECTRICAL ENGINEERING

Department of Electrical Engineering

Rajasthan Technical University, Kota

ACKNOWLEDGEMENT

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Every project big or small is successful largely due to the effort of a number of wonderful people who have always given their valuable advice or lent a helping hand. I sincerely appreciate the inspiration, support and guidance of all those people who have been there in making this project and our summer training a successful one.

I am extremely grateful to the “Electric Loco Shed, WCR, Tughlakabad, New Delhi” for the confidence bestowed in me and allowing me to held the summer training in the duration 25 May 2016 to 22 June 2016.

At this juncture I feel deeply honored in expressing my sincere thanks to Mr. S.P Singh & Mr. Dilip Agarwal for making the resource available at right time and providing the valuable insights leading to the successful completion of my project.

I express my gratitude to Mr. Jeet Shyam Singh for arranging the summer training in good schedule. I also extend my gratitude to my project guide, who assisted me in compiling the project.

I would also like to thank all the faculty members of University College of Engineering, Rajasthan Technical University, Kota for their critical advice and guidance without which this project would have not been possible.

Last but not the least I place a deep sense of gratitude to my family members and my friends who have been a constant source of inspiration during the preparation of this project.

DATE :22 JUNE 2016PLACE :Tughlakabad, New Delhi

ABSTRACT3

This shed is a West Central Railway shed on Northern Railway territory! It belongs to the Kota division. This shed was established in 1988 and was a Western Railway shed until 2003. This shed was originally built to handle locos for the freight traffic on the busy New Delhi - Bombay route. Has received a few WAG9 starting 02/08. Starting 2010 received WAM-4 locos to be operated in pairs on container trains. WAP-7 locos homed here in 2013 195+ locos.

The focus of the detailed study of this electric loco shed is to understand the working of the organization as well as to understand the functioning of the engine and various parts used to achieve the traction. Safety and system reliability concerns dominate in this domain. With such motivation various issues are tackled related to the improper functioning of the loco or the complete failure of the loco.

TABLE OF CONTENTS4

CHAPTER 1: INRODUCTION

About Indian Railways 7 Genesis of Indian Railways 9 Other milestones 10 The need for a Railway network 11 Electric Loco Shed, Tughlakabad 11

CHAPTER 2: OVERVIEW OF SECTIONS 16

CHAPTER 3: CLASSIFICATION OF LOCOMOTIVES 18

CHAPTER 4: CONTACTOR SECTION

Electromagnetic Contactor 19 Electro pneumatic Contactor 20 Drum Contactor 20 Cam Contactor 21 Principle of Contactor 22 Tap Changer 22

CHAPTER 5: RELAY SECTION 26

CHAPTER 6: TRACTION MOTOR SECTION

Working 28 Types of DC motors 28 Advantage of DC series motors 28 Traction Motors 29

CHAPTER 7: BOGIE SECTION

Bogie Classification 31 Bogie Components 32 CO-CO Tri mount Bogie 32 Tetra mount high adhesion Bogie 33 Bogie components arrangement 34

CHAPTER 8: COMPRESSOR AND EXHAUSTER SECTION

Introduction 375

ARNO Converter 37

CHAPTER 9: PANTOGRAPH SECTION

Introduction 41 Principle 41 Raising 42 Lowering 42 Reasons for using the rear panto 42

CHAPTER 10: MOH SECTION 44

CHAPTER 11: PNEUMATIC SECTION (BRAKING)

Air brake 45 Vacuum break 45

CHAPTER 12: POWER SECTION

Transformer 47 Vacuum circuit breaker 48 Potential transformer 48 Harmonic filter 50 Battery 50

CHAPTER 13: ELECTRONICS SECTION

CHBA 51 180 kV SIV Converter 51 Traction converter 52 Silicon Rectifier 53

CHAPTER 14: WHEEL SECTION 54

CHAPTER 15: LAYOUT OF LOCOMOTIVE

Bogie layout 55 Roof layout 56 Cab layout 57 Machine room for WAG9/WAP7 58 Machine room for WAP5 59

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CHAPTER 1: INTRODUCTION

1.1 About Indian RailwaysIndian Railways, a historical legacy, are a vital force in our economy. The first railway on

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Indian sub-continent ran from Bombay to Thane on 16th April 1853. Fourteen railway carriages carried about 400 guests from Bombay to Thane covering a distance of 21 miles (34 Kilometers). Since then there has been no looking back. Today, it covers 6,909 stations over a total route length of more than 63,028 kilometers. The track kilometers in broad gauge (1676 mm) are 86, 526 kms, meter gauge (1000 mm) are 18, 529 kms and narrow gauge (762/610 mm) are 3,651 kms. Of the total route of 63,028 kms, 16,001 kms are electrified. The railways have 8000 locomotives, 50,000 coaching vehicles, 222,147 freight wagons, 6853 stations, 300 yards, 2300 good sheds, 700 repair shops, and 1.54 million work force. Indian Railways runs around 11,000 trains every day, of which 7,000 are passenger trains. Presently, 9 pairs of Rajdhani and 13 pairs of Shatabdi Express Trains run on the rail tracks of India.

It is interesting to note that though the railways were introduced to facilitate the commercial interest of the British, it played an important role in unifying the country. Railways are ideally suited for long distance travel and movement of bulk commodities. Regarded better than road transport in terms of energy efficiency, land use, environment impact and safety it is always in forefront during national emergency.

Indian railways, the largest rail network in Asia and the world’s second largest under one management are also credited with having a multi gauge and multi traction system. The Indian Railways have been a great integrating force for more than 150 years. It has helped the economic life of the country and helped in accelerating the development of industry and agriculture. Indian Railways is known to be the largest railway network in Asia.

The Indian Railways network binds the social, cultural and economic fabric of thecountry and covers the whole of country ranging from north to south and east to west removing the distance barrier for its people. The railway network of India has brought together the whole of country hence creating a feeling of unity among Indians.

1.1.1 Organization OverviewThe Ministry of Railways under Government of India controls Indian Railways. The Ministry is headed by Union Minister who is generally supported by a Minster of State. The Railway Board consisting of six members and a chairman reports to this top

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hierarchy. The railway zones are headed by their respective General Managers who in turn report to the Railway Board. For administrative convenience Indian Railways is primarily divided into 16 zones:

Table 1: Railway Zones and their Headquarters

1.1.2 The Ministry of Railways has following nine undertakings:1. Rail India Technical & Economic Services Limited (RITES)2. Indian Railway Construction (IRCON) International Limited3. Indian Railway Finance Corporation Limited (IRFC)4. Container Corporation of India Limited (CONCOR)5. Konkan Railway Corporation Limited (KRCL)6. Indian Railway Catering & Tourism Corporation Ltd (IRCTC)7. Railtel Corporation of India Ltd. (Rail Tel)8. Mumbai Rail Vikas Nigam Ltd. (MRVNL)9. Rail Vikas Nigam Ltd. (RVNL)Indian Railways have their research and development wing in the form of Research, Designs and Standard Organization (RDSO). RDSO functions as the technical advisor and consultant to the Ministry, Zonal Railways and Production Units.

1.1.3 Rolling stockToday, Indian Railways have become self-reliant in production of rolling stock. It supplies rolling stock to other countries and non-railway customers. The production units are at Diesel Locomotive Works, Varanasi, Chittaranjan Locomotive Works Chittaranjan, Diesel-Loco Modernization Works, Patiala, Integral Coach Factory, Chennai, Rail Coach Factory, Kapurthala, Wheel & Axle Plant, Bangalore and Rail Spring Karkhana, Gwalior.

1.1.4 Indian Railway Catering and Tourism Corporation (IRCTC)

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IRCTC has launched on line ticketing facility with the aid of Center for Railway Information System, which can be booked on www.irctc.co.in. For the convenience of customers queries related to accommodation availability, passenger status, train schedule etc are can all be addressed online. Computerized reservation facilities have made the life easy of commuters across India.

National Train Enquiry system is another initiative of Indian Railways which offers train running position on a current basis through various output devices such as terminals in the station enquiries and Interactive Voice Response Systems (IVRS) at important railway stations.

Indian Railways are committed to provide improved telecommunication system to its passengers. For this Optical Fiber Communication (OFC) system has been embraced, which involves laying optical fiber cable along the railway tracks. In recent years Indian Railways have witnessed the marked rise of collaboration between private and public sectors. Few of the notable examples here are the broad gauge connectivity to Pipya Port where a joint venture company is formed with Pipava Port authority. Similarly Memorandums of Understanding has been signed between Railways and State governments of Andhra Pradesh, Karnataka, Maharashtra, West Bengal, Tamil Nadu and Jharkhand.

1.2 Genesis of Indian RailwaysThe story of the Indian Railways (IR) is not just a saga of mundane statistics and miles of rolling stock. It is the glorious tale of a pioneering institution that has blazed a trail for nearly a century and a half, making inroads into far-flung territory and providing a means of communication.

Indian Railway is one of India's most effective networks that keep together the social, economic, political and cultural fabric of the country intact. Be it cold, mountainous terrain or the long stretches through the Rajasthan desert, Indian Railways cover the vast expanse of the country from north to south, east to west and all in between.

More than a hundred years ago, on the 16 April 1853, a red-letter day appeared in the glorious history of the Indian Railways. On the day, the very first railway train in India ran over a stretch of 21 miles from Bombay to Thane. This pioneer railway train consisting of 14 railway carriages carrying about 400 guests, steamed off at 3:30 pm amidst the loud

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applause of a vast multitude and to the salute of 21 guns. It reached Thane at about 4.45 pm. The guests returned to Bombay at 7 pm on the next day, that is, April 17. On April 18, 1853, Sir Jamsetjee Jeejeebhoy, Second Baronet, reserved the whole train and traveled from Bombay to Thane and back along with some members of his family and friends. This was the humble beginning of the modern Indian Railway system known today for its extraordinary integration of high administrative efficiency, technical skill, commercial enterprise and resourcefulness. Today the Indian Railway (IR) is one of the most specialized industries of the world.

1.3 Other MilestoneUnder the British East India Company's auspices, the Great Indian Peninsula Railway Company (GIPRC) was formed on July 15, 1844. Events moved at a fast pace. On October 31, 1850, the ceremony of turning the first sod for the GIPRC from Bombay to Kalyan was performed. The opening ceremony of the extension to Kalyan took place on May 1, 1854. The railway line from Kalyan to Khopoli was opened on May 12, 1856. It was further extended to Poona on June 14, 1858 when the traffic was opened for public use. In the eastern part of India, the first passenger train steamed out of Howrah station for Hooghly, a distance of 24 miles, on August 15, 1854. This marked the formation of the East Indian Railway.

This was followed by the emergence for the Central Bengal Railway Company. These small beginnings multiplied and by 1880, the IR system had a route mileage of 9,000 miles in India. The Northeastern Railway also developed rapidly. On October 19, 1875, the train between Hathras Road and Mathura Cantonment was started. By the winter of 1880-81, the Kanpur-Farukhabad line became operational and further east, the Dibrugarh-Dinjan line became operational on August 15, 1882. In South India, the Madras Railway Company opened the first railway line between Veyasarpaudy and the Walajah Road (Arcot) on July 1, 1856. This 63-mile line was the first section, which eventually joined Madras and the west coast. On March 3, 1859, a length of 119 miles was laid from Allahabad to Kanpur.

In 1862, the railway line between Amritsar and Attari was constructed on the Amritsar-Lahore route. Some of the trains started by the British are still in existence. The Frontier Mail is one such train. It was started on September 1, 1928 as a replacement for the Mumbai-Peshawar mail. It became one of the fastest trains in India at that time and its reputation in London was very high. The Kalka Mail from Howrah to Kalka was introduced with the specific goal of facilitating the annual migration of British officials, their families

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and their retinue of servants and clerks from the imperial capital at Calcutta to the summer capital in Shimla. From Kalka, there was the remarkable toy train service to Shimla. Plans for this narrow-gauge train had started as early as 1847, but it was at the intervention of the Viceroy, Lord Curzon, that work actually began. Hence this train service was also known as the Viceroy's Toy Train. In order to prevent any head-on collisions on the single-track sections of this railway service, the Neals Token System has been used ever since the train was inaugurated. The train guards exchange pouches containing small brass discs with staff on the stations en route. The train driver then puts these discs into special machines, which alert the signals ahead of their approach. The Darjeeling toy trains, the Matheran toy train from Neral to Matheran, the Nilgiri Blue Mountain Railway are other engineering marvels running on routes designed and built by the British. Trains like the Deccan Queen from Bombay to Secunderabad and the Grand Trunk Express from Delhi to Madras are some other prominent trains initiated by the British. With the advancement in the railway system, electrifying railway lines began side by side, and it was in 1925, that the first electric train ran over a distance of 16 km from Victoria Terminus to Kurala.

1.4 The need for a Railway NetworkThe British rule in India was governed by three principal considerations to expand the IR system. These were the commercial advantages, the political aspect and even more importantly, the inexorable imperial defense of India against the possible military attacks from certain powerful countries showing signs of extending their orbit of influence into Central Asia.

1.5 Electric Loco Shed, TughlakabadThe Electric Loco Shed was set up in 1988 by Railway Electrification Organization (8910 sq mtrs) and comes under the TRS section of Indian Railways. The main purpose of the shed is to maintain the Electric Locomotive of the Models WAM 4, WAG 5, WAG7, WAP7, and WAG9.

Present Loco holding is around 195+. The WAG 9 & WAP 7 are the 3 phase loco where as WAM 4, WAG 5 & WAG 7 are the conventional type of loco. The main difference between the conventional and the three phase loco is that the three phase loco requires the three phase induction motor and the conventional loco requires the DC Series motor. WAG 9 model Loco is the latest model of the loco with the system of regenerative braking and also it uses various power electronics applications in it.Specification of the Loco’s in Loco Shed:(i) WAM 4:

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Manufacturers: CLWTraction Motors: Alstom TAO 659 A1 (575kW, 750V). Six motors, axle-hung, nose-suspended, force-ventilated.Gear Ratio: 15:62 originally (and still for WAM-4 2S3P), now many variations, 21:58 being common for WAM-4 6P locos.Transformer: Heil BOT 3460 A, 22.5kV / 3460kVA.Rectifiers: Two silicon rectifier cells, 1270V / 1000A each cubicle.Pantographs: Two Faiveley AM-12.Axle load: 18.8tBogies: Alco asymmetric trimount (Co-Co), same as with WDM-2, WDS-6, etc.Hauling capacity: 2010tCurrent Ratings: (WAM-4 6P) 1100A/10min, 750A continuous

Figure 1: WAM 4

(ii) WAG 5:

Traction Motors: Alstom TAO 659 (575kW, 750V, 1070 rpm) or TAO 656; or Hitachi HS 15250A, Axle-hung, nose-suspended. Six motors.Gear Ratio: 62:16 or 62:15 with Alstom motors, some 64:18 (Hitachi motors), many now 58:21 for mixed use.Transformer: BHEL, type HETT-3900. 3900kVA, 22.5kV, 182A. 32 taps.Rectifiers: Silicon rectifiers (two) using 64 S-18FN-350 diodes each from Hind Rectifier. 2700A / 1050V per cubicle.Bogies: Co-Co cast bogies (Alco asymmetric trimount -- shared with WDM-2, WAM-4).

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Axle load: 20tMax. Haulage: 2375tPantographs: Two Faiveley AM-12Current Ratings: 1100A/10min, 750A continuous

Figure 2: WAG 5

(iii) WAG 7:

Traction Motors: Hitachi HS15250-G (thicker wire gauge, better insulation);Motors built by CLW and BHEL.Gear Ratio: 65:18 (65:16?)Transformer: CCL India, type CGTT-5400, 5400kVA, 32 taps.Rectifiers: Two silicon rectifiers, cell type S18FN350 (from Hind Rectifier), 64 per bridge, 2700A / 1050V per cubicle.Axle load: 20.5tBogies: Alco High-Adhesion bogies, fabricated bogie frame assembly, with unidirectional mounting of traction motors, primary and secondary suspension.Hauling Capacity: 3010tPantographs: Two Stone India (Calcutta) type AN-12.Current Ratings: 1350A/2min, 1200A/10min, 960A/hr, 900A continuous

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Figure 3: WAG 7

(iv) WAP 7:

Manufacturers: CLWTraction Motors: 6FRA 6068 3-phase squirrel-cage induction motors (850kW, 2180V, 1283/2484 rpm, 270/310A. Weight 2100kg, forced-air ventilation, axle-hung, nose-suspended. Torque 6330/7140Nm. 95% efficiency.)Gear Ratio: 72:20Axle load: 20.5tWheel diameter: 1092mm new, 1016mm wornBogies: Co-Co, ABB bogies; bogie wheel base 1850mm + 1850mmTransformer: 7500 kVABody width: 3152mmnCab length: 2434mmPantograph locked down height: 4525mm

Figure 4: WAP 7

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(v) WAG 9:

Manufacturers: ABB, CLWTraction Motors: ABB's 6FRA6068 (850kW, 2180V, 1283/2484 rpm, 270/310A. Weight 2100kg) Axle-hung, nose-suspended.Gear Ratio: 77:15 / 64:18Transformer: ABB's LOT 6500, 4x1450kVA.Power Drive: Power convertor from ABB, type UW-2423-2810 with SG 3000G X H24 GTO thyristors (D 921S45 T diodes), 14 thyristors per unit (two units). Line convertor rated at 2 x 1269V @ 50Hz, with DC link voltage of 2800V. Motor/drive convertor rated at 2180V phase to phase, 971A output current per phase, motor frequency from 0 to 132Hz.Hauling capacity: 4250tBogies: Co-Co, ABB bogies; bogie wheel base 1850mm + 1850mmWheel base: 15700mmAxle load: 20.5tUnsprung mass per axle: 3.984tLength over buffers: 20562mmLength over headstocks: 19280mmBody width: 3152mmnCab length: 2434mmPantographs: Two Secheron ES10 1Q3-2500.Pantograph locked down height: 4525mm

Figure 5: WAG 9

The work of the various locos is spread into 10 sections whose functions and components are described under the upcoming sections.

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CHAPTER 2: OVERVIEW OF SECTIONS

1.1 SECTION M1- CONTACTOR SECTIONA contactor is a special type of switch used for closing and opening of high voltage circuits and it can be remote controlled from driver’s desk whenever necessary.TYPES OF CONTACTORS: There are four types of contactors used on locos.a) Electromagnetic Contactorsb) Electro pneumatic Contactorsc) Drum type Contactorsd) Cam Contactors

1.2 SECTION M2- RELAY SECTIONRelay is a sensitive device provided to ensure proper functioning of an apparatus either in the electrical circuit or pressure/fluid circuit to safe guard the apparatus during any abnormalities.Pressure Relays: - RGCP, QPDJ, P1, P2, RGAF, SWC, RGEB1, RGEB2Magnet Valves: VEPT 1&2, VEF, VEAD, ULV 1,2&3, IP, VESA1,2,3,4,Special type of Magnet valves: - MV4, D1 pilot (VEF- E+M combined)

1.3 SECTION M3- TRACTION MOTOR SECTIONA traction motor is an electric motor used for propulsion of a vehicle, such as an electric locomotive or electric roadway vehicle. And this section maintains the working of the traction motor.

1.4 SECTION M4- BOGIE SECTIONInitially electric locomotives were imported. But at present Chittaranjan Locomotive Works (CLW) is manufacturing electric locomotives of all types. The manufacturing capacity of CLW is 120 locos per year. There are three types of bogies generally used in Electric Locos.a) B-B Typeb) Bo-Bo Typec) Co-Co Type

1.5 SECTION M5- COMPRESSOR AND EXHAUSTER SECTIONThe purpose of the compressors is to build up compressed air required for various purposes in the locomotive. The Exhausters MPV 1 & 2 is provided for creating and maintaining Vacuum on train pipe. These motors starts working through the remote control switch BLPV. And hence Section M5 helps in maintaining the Compressor and Exhausters used in the locomotive.

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1.6 SECTION M5- PANTOGRAPH SECTIONIt is a collapsible framework mounted on loco roof. Pantograph is mounted on four base insulators. This frame is made of several metallic tubes and springs.

1.7 SECTION M6- MOH(Major Overall) SECTIONThis section opens the engine internal parts and supplies it to its respective section for the maintenance and repairing of the various equipments used in the Locomotive.

1.8 SECTION M7- PNEUMATIC SECTIONThis section deals mainly in the mechanical section such as braking and maintenance of the compressed air in the pipes.

1.9 SECTION M8- POWER SECTIONThis section is main as in terms of electrical as it deals with the power equipments such as VCB (vacuum circuit breaker), tap changer, transformer, BDV (breakdown voltage analysis), DGA (dissolve gas analysis) etc.

1.10 SECTION M9- ELECTRONICS SECTIONThis section is the maintenance of power electronics which is the latest technology being used in the latest locomotive such as SL (smoothening reactors), CHBA (battery charger), SIV (static converter), AC damping panel etc.

1.11 SECTION M10- WHEEL SECTIONThis section mainly deals with the repairing of the wheels and greasing of it. Generally in all locomotives solid wheel is used due to the needs of increase traffic, higher speed, steeper gradients all of which demand stronger braking.

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CHAPTER 3: CLASSIFICATION OF LOCOMOTIVES

The classification of Electric locomotives is based on the type of service used for. The alphabet stands for:W >>> Broad GaugeY >>> Meter GaugeZ >>> Narrow GaugeA >>> AC locosM >>> Mixed Traffic (Goods or passenger Services)G >>> Goods ServiceP >>> Passenger ServiceC >>> DC locosD>>> Diesel locosCA >>> AC/DC locosU>>> Multiple units(EMU, DMU)

And the number after it represents the model number of that locomotive.EXAMPLE: If we want to name a locomotive which is used in broad gauge with AC supply and for goods and model 7. How would it be written?ANSWER: WAG 7

EXAMPLE: If we want to name a locomotive which is used in meter gauge with diesel loco and used for passengers and model 2. How would it be written?ANSWER: YDP 2

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CHAPTER 4: CONTACTOR SECTION

A contactor is a special type of switch used for closing and opening of high voltage circuits and it can be remote controlled from driver’s desk whenever necessary.

TYPES OF CONTACTORS: There are four types of contactors used on locos.

a) Electromagnetic Contactorsb) Electro pneumatic Contactorsc) Drum type Contactorsd) Cam Contactors

4.1 ELECTROMAGNETIC CONTACTORS: In this type of contractors and electromagnet is used for operating the driving mechanism. When the switch BLCP is closed the contactor coil gets magnetized. The armature attached to the actuating rod is attracted by electromagnet. So the armature comes in contact with the magnet. Due to this action the actuating rod is operated and the mobile jaw of the contactor moves upwards and comes in contact with fixed jaw. Now high tension circuit is closed and the receiver starts functioning. When the switch is opened the electromagnet gets reenergized, the armature is pulled back to its original position by the action of return spring. Due to this action the jaw of the contactor is moved downwards so that the HT circuit gets opened and the receiver stops working. A flexible shunt is provided with mobile jaw for easy movement which is in the shape of pigtail. A blow out coil is provided for extinguishing the arc produced between the fixed and mobile jaws at the time of opening of the contactor. Ex. C 101, C 105, C 106, C 107, C 118 etc.

Figure 6: Electromagnetic Contactor

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4.2 ELECTRO PNEUMATIC CONTACTORS: In this type of contactor the driving mechanism is operated by the servomotor. The air pressure for the servomotor is admitted by operating the electro valve, which is operated by an electromagnet.

When the switch is closed the electromagnet gets energized and attracts the armature when the armature moves upwards the valve closes the passage between B and A chambers and opens the passage between C and B chambers. Due to this action the air from C chamber enters to B chamber of servomotor. Through B chamber, the air pressure operates the piston towards upwards, so that the actuating rod is moved upwards and makes the mobile contact to come in contact with fixed contact. So that the contactor is closed and motor starts functioning. When the switch is opened the electromagnet gets de-energized and the valves are pulled back to their original position by the action of return spring. Due to this action the valves closes the passage between C and B chambers and opens the passage between B and A chambers, the exhaust air from B chamber of servomotor gets exhausted through A chamber exhaust hole, hence the return spring pushes down the servomotor piston so that the actuating rod is operated which in turn pulls back the mobile jaw and the contactor gets opened. Example Line contactors and shunting contactors.

Figure 7: Electro Pneumatic Contactor

4.3 DRUM CONTACTORS: In this type of contactor an insulated drum is used for closing and opening the circuit. The drum is rotated by two pistons of servomotor and the air for the servomotor is admitted by the action of two electro valves. Two copper segments are fixed on

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the drum with socket head screws separately which will act as mobile jaw and closes the circuit.

Whenever the drum is rotated the copper segments are connected with the HT circuit through fixed contacts (finger contacts). On one side the segment ‘a’ is connected with finger contact ‘F’. Due to this action the circuit is closed and current will flow in one direction (forward). When the drum is rotated on the opposite direction the segment ‘a’ leaves the contact with finger contact ‘F’ and segment ‘b’ will come in contact with finger contact ‘R’. Now the circuit is closed in reverse direction and the current flows to the TM field in the reverse direction. Blow out coils are not provided on drum contactors since they are operated under no load conditions. Example Reverser J1 and J2.

Reverser J 1 is for changing the direction of flow of current for TMs 1, 4 and 2 and reverser J 2 is for changing the direction of flow of current for TMs 3, 6 and 5. The position of the manual operating handle should be in upward direction when cab – 1 is leading and it should be in downward direction when cab – 2 is leading.

4.4 CAM CONTACTORS: In this type of contactor one or more switches can be operated with the help of cams fixed on a shaft and operated through pinion and gear. The pinion and gear is operated with the help of SMGR servomotor. A cam is around disc made with an insulating material. Required number of grooves are made on the circumference of the cam. A roller is attached to the mobile jaw and placed on the cams. When the shaft is rotated the cam also rotates. During the movement of the cams the rollers come out from the grooves and make contact with fixed jaw and close the circuit. When the roller moves inside the groove the mobile jaw leaves the contact with the fixed jaw to make the circuit open. The opening and closing of the mobile jaw will depend up on the number of grooves arranged on the cams according to the sequence of our requirement. Example CGR – 1, CGR – 2, CGR – 3.

Figure 8: CAM Contactor22

4.5 PRINCIPLE OF CONTACTORS: The switches in the loco are remote controlled from Driver’s cab. These switches which are controlled from a distance are called contactor. A contactor has three main parts:

1. The contact position which consist of fixed jaw, mobile jaw, flexible shunt, Insulator and axle.2. The driving mechanism which acts as a movable jaw.3. The remote control arrangement is worked by 110 V battery, which energizes the driving mechanism.

S.No Description Ideal Value Instrument Used1. Pick up voltage 57-68V Voltmeter2. Drop out voltage 10-20V Voltmeter3. Distance between the contactors 40mm (min) Scale4. Width of fixed contact 3mm Scale5. Width of moving contact 3mm Scale6. Distance between the fixed and moving contact 8.5±1mm Go-no-Go gauge7. Resistance of coil 550+8% Ω Multimeter8. Crushing distance 3.8-4.8 mm Go-no-Go gauge9. Contact pressure 700-900 gm Gram gauge10. Distance between fixed contact and blow out

coil support53±0.5 mm Scale

11. Insulation resistance between the connection Not less than 1 MΩ

Meager

Table 2: EM contactor testing parameters and instruction

4.6 TAP CHANGER: The output voltage of a transformer varies according to the turn’s ratio of the primary and the secondary windings of the transformer. It can be appreciated that at any point of the primary or the secondary winding the voltage is different from any other point on the same winding because these points are at different ratios with respect to the other winding. Hence each and every tap brought out from the winding gives a different voltage. Broadly tap-changers can be divided into two categories-namely off-load and on-load.

Off-load tap-changers cannot be operated while current is flowing in the circuit. Off-load tap-changers are used mainly for non-critical applications where a momentary interruption in the current can be tolerated. Hence, such tap-changers have no use in traction duty.

In traction only on-load tap-changers (OLTC) are used. They are capable of changing the taps rapidly without interrupting the flow of current.

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a) WORKING PRINCIPLE: The tap changer is directly built on to the transformer. The tappings of the auto transformer winding are brought out and arranged in circular fashion in two rows on an insulated contact plate. There are two rows of contact segments which are arranged on outer and inner circle of the contact plate. An arm which is known as selector arm driven by a shaft at the centre of contact plate. Two rollers are fixed at the edge of the selector arm. These rollers make connection between respective segments (even and odd numbered notches) and outer or inner rings. These rings are provided in front of the tap changer casing is driven by an air servomotor known as SMGR. The design of the air servomotor is such that once the selector arm begins it movement it can only be stopped at the required tap (not in between two taps). The connection between the inner and outer rings to the transformer is being established by means of CGR contactors.

b) OPERATION: The selector arm is actuated by driving shaft through an intermediate gearing comprising of driving wheel, lateral gear pinion and stepping wheel. This driving shaft also operates CGR cam shaft in sequence with the operation of contact rollers. For opening and closing sequence of CGR contacts are as follows:

CGR 1 CGR 2 CGR 3Half Notch (1/2 notch) Close Close CloseOdd Notch (1,3,5……..31) Close Open OpenEven Notch (2,4,6……..32) Open Close Close

Before the moving contact rollers leaves the zero tap contact segment it touches the first tap segment. During this CGR2 contactor closes and inserts the diverter resistance RGR in between the tapings of winding. Thus the winding between tap zero and tap 1 is coming in series with the resistance RGR, which limits the circulating short circuit current due to the emf difference between tap 1 and tap zero (No of turns of auto transformer). When the contactor arm further moves fully on to tap 1 the inner contact roller breaks contact with zero tap. Mean while CGR 2 contacts open and cut off the resistance RGR from circuit. Likewise when selector arm moves from 1st tap to 2nd tap the contact roller (outer) will continue to make connection with tap 1 segment and the inner contact roller establishes the contact between inner segment to inner ring (this is due to over lapping of contact segment) at the same time CGR 1,2 are closed again to insert the resistance RGR in between the short circuited winding. (Now the current flows from the contact ring outer to). When the selector arm further moves, the outer roller leaves contact with tap 1 segment and breaks the contact. At the same time CGR 1 gets opened and CGR 2 and 3 gets closed. This again cuts off the resistance RGR from

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the circuit. The opening and closing of CGR contacts is carried out by a cam shaft which is driven by the main shaft through gear mechanism. This ensures a perfect relationship between the movement of selector arm and the operation of CGR contact. A high resistance RPGR serves as the connection between equal potentials, which ensures that the branches of circuit being interrupted at a given potential.

c) WORKING PRINCIPLE: When ever any control command is given to the solenoid of UP or DOWN valve the respective valve gets energized and transmits pressure pulses to the control block cylinder. This causes the lever arm with toothed segment to rotate about the pivot either towards the right or left with respect to the energizing of progression or regression coil. The toothed segment engages with the pinion which carries the axes of planetarian wheel the annulus is stationary. Movement of the planet wheel causes the cam shaft to rotate in one direction or the other direction through 75˚(known as lead angle). This induces the displacement of cam shaft relative to the crankshaft position as long as the control command persists. Since the cam shaft is displaced by 75˚ the operating piston is actuated and drives the crank shaft through half rotation. The other half rotation is completed by kinetic energy stored in the flywheel mechanically such that the motor can complete one tap change operation entirely. The crank shaft in turn rotates the com plates through a spur gear and an intermediate wheel. The cam Plate is operating the auxiliary switches of the control circuit. There are four cylinders, two for notching up and two for notching down. For notching up cylinder no 1 is vented and for notching down cylinder no 3 is vented and cylinder no 4 is pressurized. Venting and pressuring of cylinder is decided by the piston of the 3-way valve which is operated by the cam shaft through valve push rod. There is a notching lever with spring arrangement provided in the crankshaft to hold the shaft at the tapings when no air pressure is available. This also ensures that the crankshaft stops in the correct position. A mechanical interlock called limit stop is coupled with the crankshaft which prevents the over running the limit position i.e. beyond zero or 32 notches when the mechanism is operated by hand.

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CHAPTER 5: RELAY SECTION

Relay is a sensitive device provided to ensure proper functioning of an apparatus either in the electrical circuit or pressure/fluid circuit to safe guard the apparatus during any abnormalities.Mechanical Relays Electrical RelaysAir Flow Oil

FlowVoltage Relay

Current Relay

Earth Fault Relay

Signaling Relay

Functional Relay

QVSI 1,2QVSL 1,2QVM 1,2QVRHQVRF

QPH Q20Q30QCVAR

QLMQLAQRSI 1,2QD 1,2QEQF 1,2

QOP 1,2QOA

QV60QV61QV62QV63QV64QVLSOL

Q44, Q45, Q46,Q47, Q48, Q49,Q50, Q51, Q52,Q118, Q119,Q100, QTD105,QTD106, PR1,PR2, QFL,QWC, QPV

Table 3: Relay's used in LOCO

Pressure Relays: - RGCP, QPDJ, P1, P2, RGAF, SWC, RGEB1, RGEB2Magnet Valves: VEPT 1&2, VEF, VEAD, ULV 1,2&3, IP, VESA1,2,3,4,Special type of Magnet valves: - MV4, D1 pilot (VEF- E+M combined)QLM: The relay QLM is fed by means of the high voltage current transformer TFILM, which causes high voltage circuit breaker DJ to trip out, if the current taken in by the main transformer exceeds the setting value of the relay.QOP: Voltage operated relay for earth faults in main traction circuit and DJ.DJ: Opens under the control of various protection devices. From 'disjoncteur', French term for circuit breaker.QOA: Earth fault protection of auxiliaries and opens the DJ.QRSI 1, 2: The relays QRSI 1-2 are fed by means of the rectifier current transformer RSILM 1 and 2 (4000/5A) which cause the high voltage circuit breaker to trip, if the current taken in by the rectifiers exceeds the setting value of the relays (3600 A).QD 1, 2: Wheel slip relays are of differential type. When the current difference is 125 A in between traction motors 2 and 3 and traction motors 4 and 5, the relay operates. In case of wheel slipping, it feeds relay Q-48, thereby energizing sanding electro valves VESA and sand is applied to corresponding wheels Relay Q-51 is also energizes causing regression of tap changer till the slipping stops.QOP 1, 2: In case of failure of insulation of traction power circuit to earth, the battery supply available across the allows to pick up the relay through the earth fault path and in turn opens the HV circuit breaker DJ. The switch HQOP 1-2 makes it possible to isolate the relay QOP 1 or 2 and inserts a resistance RQOP in the earthed path in order to limit the fault current. Otherwise it will not be possible to switch on again the circuit breaker DJ to clear the section and bring the locomotive to the shed.

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Q 20: Relay Q-20 with series resistance RQ-20 is connected across rectifier output and causes buzzer SON 1-2 to work. The relay picks up if, TM voltage exceeds 854 V. When voltage falls to 740 V, the Q20 relay resets and buzzer stops working. Only in YAM-1 - Sounds a buzzer if voltage for traction motors is exceededQ 30: The relay Q-30 drops out if the single-phase auxiliary winding voltage drops below 215 volts. Its contacts switch off relay Q-44, thereby tripping DJ. Relay Q-30 is switched on directly through the contacts of the relays Q-45 and remains in the circuit with series resistor RQ-30 after the relay Q-45 opens/drops. Opens DJ if catenary loses power.QCVAR: Relay QCVAR has been put across ‘W’ phase and neutral of ARNO to ensure that the ARNO starting resistance is 118 is disconnected from the circuit when generated face voltage is in between 150 to 160 V AC. This cuts out ARNO starting contactor C118. The relay picks up at 155-160 volts AC.QV 61: This relay is provided across battery charger CHBA and indicates the working of the charger. This relay is English Electric make picks up below 68V DC.QRS: Relay QRS is energized when the loco is in running condition and de energized when the brake is applied. This relay operates through its N/C contacts and regresses the tap changer.QE: The relay QE is fed by means of the excitation current transformer which causes the braking excitation contactor C145 to trip out, if the current taken by the excitation winding of the motors exceed the setting value of the relay (900 A).QF 1,2: The relays QF 1-2 are connected through the shunts SHF 1-2, which cause the braking excitation contactors C-145 to trip out, if the current in the braking resistance RF-1 and 2 exceeds the setting value of the relays (900 A).QPH: Trips DJ if oil flow in main transformer fails.QVM 1, 2: Detects failure of traction motor blowers and trips DJ.Q 52: Trips DJ if incorrect notching occurs in tap changer.Q118: A time delay which opens the DJ in the event of auxiliary failure.QVRH: Relay to check the working of MVRH (Motor blower to cool the Transformer oil).

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CHAPTER 6: TRACTION MOTOR SECTION

Motor is machine which converts the electrical energy into mechanical energy. DC motor works on the principle of attraction and repulsion.

6.1 WORKING: When the switch ‘H’ is closed the inductor and armature are energized. The inductors posses some polarity. The armature is get before the inductors in such a way so that to maintain equal polarity to the inductor on either sides. Since like poles repel each other, now the armature and inductor will try to be away from each other. The inductors are stationary. So they will not move. But armature is movable, so it will move and starts rotating. At the same time the other inductor will attract the unlike pole of the armature towards it, there by the rotation of the armature increases. Now, when the armature rotates the polarity of the armature is charged by the commutator in such a way so that it keeps equal polarity in front of the other inductor at the time of the arrival towards it. So, again the reputation and attraction takes place and rotation of the armature continues. The commutator continues to change the polarity of armature poles at appropriate time, there by the motor rotates until the switch H is opened. The motor provided with the tow inductors is known as two pole motor. If it is of four inductors then it is four pole motor and so on.

6.2 TYPES OF DC MOTORS:

1. Separately excited motor2. Series excited motor.3. Shunt excited motor.

Out AC locos are provided with DC series excited motors. In this type of motor armature and inductors are connected in series to a single DC source. So it is called as series excited motor. They are most useful for traction purpose.

6.3 ADVANTAGE OF DC SERIES EXCITED MOTOR:

1. Starting torque of is very high (torque in the force that tends to produce a turning effect on the shaft).2. Reversal of the rotation of the motor is very easy.3. Variable speed is possible than by any other type of DC motors.Reversing the direction of the rotation of a motor: For reversing the direction of rotation of motor the direction of the flow of the current should be changed either in the field or in the armature coil. But, if the direction of flow of current is

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charged in the both field as well as armature, the rotation of the motor will not change. On AC locos for changing the direction of rotation of the traction motor the direction of flow of current is changed in the fields (inductors) with the help of reversers. This in turn will reverse the direction of the locomotive.

Note: The reversal of the rotation should be done after stopping the motor (i.e. locomotive). Otherwise serious damages will be caused.

6.4 TRACTION MOTORS: In WAG-5 loco, TM-1, 2, 3 are provided in bogie-1 and TM-4, 5, 6 are provided in bogie-2. These motors are axle-hung, nose suspended type. There are two types of traction motors supplied by CLW i.e., TAO 659 & Hitachi.

Grease lubricated roller bearings are used for the armature & for suspension in Hitachi motors. In TAO 659 motors, Roller bearings for the armature & white metal plain sleeve bearings for suspension are used.

Special provision has been made in design of the motors to ensure that locomotive can be operated satisfactorily on flooded track, to a maximum flood level of 20 cm above rail level.

MAKE CLW CLWType HS 15250 A TAO 659Continuous output 630 KW 585 KWVoltage 750 V 750 VStarting current 1350 A 1100 ACurrent (continuous) 900 A 840 ASpeed 895 rev/min 1060 rev/minMaximum service speed

2150 rev/min 2500 rev/min

Insulation CLASS C CLASS HNumber of poles Main 6,

Interpoles 6Main 6,Interpole 6

Table 4: Traction Motor details

There are total 6 traction motors used in the WAG 9/ WAP 7 loco. TM 1-2-3 are mounted in bogie 1 and fed from traction converter 1 whereas TM 4-5-6 are mounted in bogie 2 and fed from the traction converter 2. In case of WAP 5 there are 4 traction motors in which traction converter 1 fed to TM 1-2 where as traction converter 2 fed to TM 3-4.

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Unlike conventional WAG 5/7 individual TM cannot be isolated in this loco only group isolation is possible. For isolation of TM group one rotating switch number 154 is provided in SB-1, its normal position is ‘NORM’.

In WAP 7 and WAG 9 the traction motor is forced air cooled and intended for transverse installation in a 3 motor bogie. Traction motor is suspended on axel, by axel cap at one end and on link at another end.

Figure 9: Traction Motor mounted on Wheel

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CHAPTER 7: BOGIE SECTION

Bogies in locomotive are provided to permit long length of locomotive body to negotiate the curves. A small length of bogie is desirable. The length of bogies is decided by the distance between the centre of extreme wheels of bogie is known as bogie wheelbase. Bogie wheelbase shall be well proportioned to permit the bogie negotiating the curve and jerking. The bogie has two a more bogies on which the body is mounted. The distance between the centers of extreme wheels is known as the total wheelbase.

7.1 BOGIES CLASSIFICATION: Bogies are classified on

1) Number of axles2) Type of axle drive

The type of axle drive and number of axles in the bogie is also called the wheel arrangement. Wheel arrangements are classified as B, BO and CO.

B: Two axles, axles are mechanically coupledBO: Two axles, axles are independently drivenCO: Three axles, axles are independently driven

Locomotive always have two or more bodies. So the wheel arrangement of the locomotive is designed as B-B, BO-BO and CO-CO. Initially electric locomotives were imported. But at present Chittaranjan Locomotive Works (CLW) is manufacturing electric locomotives of all types. The manufacturing capacity of CLW is 120 locos per year. There are three types of bogies generally used in Electric Locos.

a) B – B Type: - These types of bogies are available in WAG-1 and WAG-4 locomotives. In this type one traction motor has to drive two axles in a bogie through a gear system. Each loco will have two bogies i.e. two TMs per loco. This type is also named as monomotor bogies.

b) BO – BO Type: - Each bogie is having two axles driven by TMs independently i.e. each loco will have 4 TMs. These types of bogies are available in WAM-1 and 2 locos. (At present these types of locos are not available in SCR).

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c) CO – CO Type: - This bogie is having three axles in each bogie driven by three independent TMs. These bogies are available in WAM-4, WAG-5A, WAP-1, WCG-2, WCM-5, WCAM-1 types of locos. Each loco is having two bogies i.e. total six traction motors.

Wheel Arrangement

Locomotive Type

B-B WAG1, WAG2, WAG4, WAM1BO-BO WAM1, WAM2, WAM3, WAP5CO-CO WAM4, WAG5, WAG6C, WCAM1, WAP1-3BO-BO-BO-BO WAG 6A, WAG 6B

Table 5: Bogie arrangement

7.2 BOGIE COMPONENTS: The bogie of a locomotive is an assembly of following components.1. Bogies Frame2. Wheels3. Axles4. Springs5. Axle Boxes6. Supports for Traction Motors7. Supports for Brake Rigging & Brake Cylinder8. Friction Dampers / Snubbers.

7.3 CO-CO TRIMOUNT BOGIE: Majority of the locomotives in Indian Railways is provided with this type of bogies. The bogie consists of single piece cast steel bogie frame carrying the center pivot in the cross member located towards the end of the locomotive. Center pivot carries 60% of vertical load; it receives and transmits Tractive and braking forces. The side bearers take the other 40% of vertical load. The side bearers do not receive or transmit Tractive and braking forces. The frame is supported by four sets of double equalizers extending from the end axles to the center axle. Full equalization is obtaining by suitable positioning the springs and controlling their working height. The weight of locomotive body is transferred to the bogie at center pivot and two side bearers to form a three point supports. This type of bogie is known as Tri-mount Bogie.

Suspensions: - Suspensions near bogie are provided to reduce the vibration. The vibrations are picked up by the wheel, which is mounted on railway track which if self is shaking up and down due to irregularities in the surface. The suspension system also balances the vertical

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loads between the wheels and provides passenger comfort by reducing vibrations in the vehicle body. The suspension between the axle and the bogie frame constitutes the primary suspension. The suspension between the bogies frame and vehicles body is called secondary suspension. Suspension, consisting of four groups of helical coil springs. Each group of springs consists of two nests of one outer and one inner coil. To prevent uncontrolled bouncing effect of locomotive body supported on helical coil springs damper is provided as a resisting force.

Types of dampers are: -

1. Friction Damper2. Hydraulic DamperIn Tri-mount bogie friction damper or snubber is provided on four of the inner coils of each bogie.

7.4 TETRA MOUNT HIGH ADHESION BOGIE: This bogie is provided for WAG7 locomotives.

Introduction: - With increasing demand of heavy freight traffic on Indian Railways, a new high adhesion bogie has been developed by RDSO for high horse power freight locomotive to achieve higher Tractive effort of 42 tones at start. The bogies exhibit better adhesion characteristics with reduced weight transfer.

General Arrangement of Bogie: - This a three-axle type bolster less bogies with two-stage suspension, floating pivot and unidirectional arrangement of axle hung nose suspended traction motors. Bogies frame is of straight and fabricated box type construction with three transoms to carry nose suspension.

The locomotive body weight is supported on bogie frame through four rubber side bearers directly mounted on bogie side beams. Shims have been provided below outer side bearers to distribute load on side bearers in a 60%: 40% ratio, 60% of load being supported on side bearers adjacent to centre pivot and 40% of the load at remaining two side bearers. Center pivot does not take any vertical load and is used only form transfer of traction and braking forces. The bogie frame in turn is supported on axles through helical coil springs mounted on equalizer beams. The equalizing mechanism consists of equalizers hung directly on end axle boxes and supported on middle axle box through a link and compensating beam arrangement. The equalizing mechanism enables achievement of equal axle loads on uneven track and reduces weight transfer at start.

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Suspension Arrangement: - The bogies has two-stage suspension with helical coil springs between axle box and bogies frame in primary stage and side bearers (rubber sand which) between bogies frame and locomotive body in secondary stage. The lateral stiffness of rubber springs is utilized to provide to provide lateral guidance at the secondary stage. Four vertical hydraulic dampers, one with each nest of primary springs & Two lateral hydraulic dampers are provided in secondary stage to supplement the damping provided by side bearers both in lateral and rotational modes which prevents nosing at high speed. Two lateral rubber stops are provided on each bogie on either side of the middle axle to limit lateral movements. Vertical stops are provided on bogie frame to limit vertical movement between axle boxes and bogie frame.

Roller Bearing Axle Boxes: - Movable axle journal boxes are mounted in pedestals or horns, fabricated integral with the frame. Lateral play for negotiating curves and turnouts is obtained by the movement of axle boxes in horns. End axle boxes are provided with rubber thrust pads to cushion lateral thrust, while 10 mm lateral plate is provided on middle axle boxes.

7.5 BOGIE COMPONENTS ARRANGEMENT:

Figure 10: Bogie components

Bogie Frame: Can be of steel plate or cast steel. In this case, it is a modern design of welded steel box format where the structure is formed into hollow sections of the required shape.

Bogie Transom: Transverse structural member of bogie frame (usually two off) which also supports the car body guidance parts and the traction motors.

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Brake Cylinder: An air brake cylinder is provided for each wheel. A cylinder can operate tread or disc brakes. Some designs incorporate parking brakes as well. Some bogies have two brake cylinders per wheel for heavy duty braking requirements. Each wheel is provided with a brake disc on each side and a brake pad actuated by the brake cylinder. A pair of pads is hung from the bogie frame and activated by links attached to the piston in the brake cylinder. When air is admitted into the brake cylinder, the internal piston moves these links and causes the brake pads to press against the discs. A brake hanger support bracket carries the brake hangers, from which the pads are hung.

Primary Suspension Coil: A steel coil spring, two of which are fitted to each axlebox in this design. They carry the weight of the bogie frame and anything attached to it.

Motor Suspension Tube: Many motors are suspended between the transverse member of the bogie frame called the transom and the axle. This motor is called "nose suspended" because it is hung between the suspension tube and a single mounting on the bogie transom called the nose.

Gearbox: This contains the pinion and gearwheel which connects the drive from the armature to the axle.

Lifting Lug: Allows the bogie to be lifted by a crane without the need to tie chains or ropes around the frame.

Motor: Normally, each axle has its own motor. It drives the axle through the gearbox. Some designs, particularly on tramcars, use a motor to drive two axles

Neutral Section Switch Detector: In the UK, the overhead line is divided into sections with short neutral sections separating them. It is necessary to switch off the current on the train while the neutral section is crossed. A magnetic device mounted on the track marks the start and finish of the neutral section. The device is detected by a box mounted on the leading bogie of the train to inform the equipment when to switch off and on.

Secondary Suspension Air Bag: Rubber air suspension bags are provided as the secondary suspension system for most modern trains. The air is supplied from the train's compressed air system.

Wheel Slide Protection System Lead to Axle box: Where a Wheel Slide Protection (WSP) system is fitted; axle boxes are fitted with speed sensors. These are connected by means of a cable attached to the WSP box cover on the axle end.

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Loose Leads for Connection to Car body: The motor circuits are connected to the traction equipment in the car or locomotive by flexible leads shown here.

Shock Absorber: To reduce the effects of vibration occurring as a result of the wheel/rail interface.

Axle box Cover: Simple protection for the return current brush, if fitted, and the axle bearing lubrication.

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CHAPTER 8: COMPRESSOR AND EXHAUSTER SECTION

8.1 INTRODUCTION: Auxiliary Motors (often referred to as compressor and exhauster in LOCO) used in loco is 3 phase AC Induction Motors. The motor are has 3 sets of stator coils which are energized by 3 Ø AC supply and the rotor coils are fed by induction, and hence it is called a 3 Ø Induction Motor.

TYPE OF MOTOR

HP KW RPM RELAY POLE SWITCH BEARINGS CONTACTORS

MPH 4.3 3 2880 QPH 2 HPH 6305 --MVSL 1,2 3.0 3 2960 QVSL 1,2 2 HVSL 1,2 6306 --MVSI 1,2 3.0 2.2 2960 QVSI 1,2 2 HVSI 1,2 6306,6204 --MVRH 30 22 1440 QVRH 4 HVRH 6313,6312 --MVMT 1,2 35 26 2960 QVMT

1,22 HVMT

1,26313,6312 --

MCP 1,2,3 14.5 10.4 985 -- 6 HCP 6310 C101,102,103MVRF DC -- -- 3000-

4000QVRF -- -- 6409 --

MVRF A/C 30 22 -- QVRF 2 -- -- C108MPV 1,2 -- -- 985 -- 6 HPV 1,2 6309 C111,112MCPA (DC) 1.0 -- 1500 -- -- ZCPA 6306,6304 --

Table 6: Auxiliary motors in LOCO

8.2 ARNO CONVERTER: The single phase supply of 380 volts AC is fed direct to the ‘U’ and ‘V’ phases of the Arno converter. Since the Arno Converter is connected to single phase supply, no starting torque is developed. For starting the ‘Arno’ a split phase starting method has been employed. The ‘W’ phase winding is connected to the supply phase U through a starting resistor R-118 and starting contactor C-118 for a short duration to start the Arno. Thus unbalanced three phase voltage is impressed to each phase winding of Arno Converter and the starting torque is developed. The Arno Converter picks up speed within 5 seconds. After the Arno has gained sufficient speed, the phase ‘W’ is opened from the starting circuit by starting contactor C-118. If the starting phase fails to open out within 5 seconds after Arno gained its

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rated speed, there will be excessive vibration of the Arno and Overheating of the Arno starting resistor. An interlock of relay ‘QCVAR’ opens C-118 coil circuit, to protect against overheating.

The neutral point’0’ of the Arno is connected to an earth fault relay QOA, which performs the same function as the relay QOP, in power circuit. The relay QOA trips the circuit breaker (DJ) of the locomotive in the event of an earth fault in the auxiliary circuit. The switch HQOA and RQOA perform the same functions as the switch HQOP and resistor RQOP in the power circuit. In addition, the relay QOA is permanently shunted by a resistance RPQOA.The Arno converts the single phase input into 3-phase output as 380V± 22.5%.The ratio of negative sequence voltage to positive sequence voltage is within 5%. The 3-phase output of the Arno converter is connected to the auxiliary motors.RATINGS: - Make Jyothi

1-phase input 3-phase inputkVA 150 kVA 120Voltage 380 V±22.5% Voltage 380 V±22.5%Current

395 A Current

190 A

BLOWER MOTOR FOR SILICON RECTIFIER (MVSI 1&2): Each rectifier cubicle is provided with one blower, which is driven by the motor MVSI. The motors of rectifier cubicle are controlled by means of switch HVSI 1&2 which are provided on RSI 1 & 2 blocks respectively. The cooling of rectifier is monitored by the airflow relay QVSI 1&2. The interlock of QVSI 1 &2 are connected in series with relay Q44. In the event of any MVSI 1 & 2 fails to work, respective air flow relay QVSI does not pick up and its interlock opens on Q44 branch causing de-energisation of Q44 in turn trips DJ. Incase MVSI 1 & 2 are working normal and QVSI1 & 2 relays found defective, respective relay can be by-passed through HVSI 1&2 switches. These are directly start motors along with ARNO. This is an axial flow motor with 2.2 kW capacity.Following are the positions of HVSI switches:

Position 0: - QVSI and MVSI isolated

Position 1: - QVSI and MVSI in service

Position 2: - QVSI in service and MVSI isolated

Position 3: - MVSI in service and QVSI isolated

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BLOWER MOTOR FOR SMOOTHING REACTOR (MVSL 1&2): These motors (MVSL1&2) are used for cooling smoothing reactor 1& 2. Proper working of motors (MVSL1&2) can be ensured by airflow relays QVSL1&2 respectively. The switches HVSL1&2 are provided on the TB board for controlling working of Motors & relays. Whenever any blower does not work, respective relay de-energizes and trips DJ through relay Q118.These are directly start motors along with ARNO. This is an axial flow motor with 2.2 kW capacity. Following are the positions of HVSL switches:

Position 0: - QVSL and MVSL isolated

Position 1: - QVSL and MVSL in service

Position 2: - QVSL in service and MVSL isolated

Position 3: - MVSL in service and QVSL isolated

OIL PUMP FOR CIRCULATING OF TRANSFORMER OIL (MPH): The purpose of this motor is to drive the oil pump to circulate transformer oil. A relay QPH is provided to check working of the oil pump. QPH is a pressure relay provided on the pipeline of the oil circulating system of transformer in the H.T compartment. When the pump is not working properly, the relay causes tripping of DJ. HPH is provided on TB board for controlling MPH and QPH .The MPH is a directly start motor and starts along with the ARNO. Following are the positions of HPH switch:

Position 0: - QPH and MPH isolated

Position 1: - QPH and MPH in service

Position 2: - QPH in service and MPH isolated

Position 3: - MPH in service and QPH isolated

MAIN COMPRESSORS (MCP 1, 2, 3): The purpose of these compressors is to build up compressed air required for various purposes in the locomotive. These motors starts working through contactors C101, C102, C103.These contactors can be switched ON by switch BLCP (automatic) or by BLCPD (direct) on the Loco Pilots' desk. Main Compressor Governor RGCP is provided to regulate the working of the compressor by opening and closing the contactors at preset value (closes at 8 kg/cm2 and opens at 9.5 kg/cm2). A direct switch BLCPD is provided to bypass RGCP and to make compressors to work continuously to build up pressure until Safety valve (SS2) blows at 10.5 kg/cm2. Compressors can be selected according to requirement through HCP.

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EXHAUSTERS (MPV 1-2): The Exhausters MPV 1 & 2 is provided for creating and maintaining vacuum on train pipe. These motors starts working through the remote control switch BLPV. When BLPV is closed, according to ZPV positions, MPV-1 or MPV-2 will work. MPV-1 starts working by closing C-121 Contactor and MPV-2 by closing C-111 Contactor. These exhausters are provided with oil sumps for lubrication and provided with dipstick to check the oil level in the sump.

BLOWER FOR COOLING TRANSFORMER OIL (MVRH): The transformer oil cooling blower motor is provided for cooling the transformer oil in the radiator. On closing BLVMT first C-107 contactor closes and MVRH starts working. There is a relay QVRH to check the proper functioning of this blower. Switch HVRH is provided on TB board for controlling MVRH and QVRH. Switch HVRH has four positions same as HVSI.

BLOWER MOTORS FOR TRACTION MOTOR (MVMT 1-2): These blower motors (MVMT-1&2) are required to cool the traction motors in bogie 1 and 2 respectively. MVMT-1 starts working through C-105 contactor and MVMT-2 starts working through C-106 contactor. The switch BLVMT is common for starting MVRH, MVMT 1 &2. The blowers will start one after the other with a time delay of 8 Sec with the help of QTD 105 and QTD 106. Airflow relays QVMT 1&2 are provided to check the proper functioning of these blowers. If the blowers are not working properly, the particular relay interlock will open on Q118 branch of DJ control circuit and trips the DJ. Switches HVMT 1&2 are provided on TB board for controlling MVMT 1&2. Switch HVMT 1&2 has four positions same as HVSI.

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CHAPTER 9: PANTOGRAPH

9.1 INTRODUCTION: It is a collapsible framework mounted on loco roof. Pantograph is mounted on four base insulators. This frame is made of several metallic tubes and springs. Ball bearings are provided for easy movement of articulations and at each joint, flexible shunt are provided to give continuous flow of current. On the top frame of the pantograph, panto pan is provided to collect the current from OHE. Panto pan is made up of high carbon strips, which can be replaced when worn out. Normally the panto is in lowered position by the tension of lowering springs provided inside the servomotor. When compressed air is admitted inside the servomotor, piston is operated and compresses the lowering spring.

The piston rod is attached to the rocker arm and releases actuating rod, thereby the cam is released and operates the lower articulation drum. When the lower articulation drum is operated, the lower articulation is raised upwards by the action of raising springs. The upper articulation, which is connected to the lower articulation at free end, will also rise by the action of thrust rod. Thereby the upper articulation will rise. The tension of lower spring is more than the raising spring. So it is necessary to admit the compressed air inside the servomotor continuously. For lowering the panto, it is enough to exhaust the compressed air from the servomotor; thereby with the action of lowering spring panto lowers. Which in turn operates the lower articulation rod against the tension of rising spring, due to this action the lower articulation is pulled down and upper articulation is also pulled down simultaneously by the action of thrust rod. The admission and exhausting of compressed air in the servomotor is controlled by electro valves (VEPT1 & VEPT2), which are remotely controlled by ZPT from Loco Pilot’s desk. Each loco consists of two pantos. These are electrically connected by means of HPT1, HPT2 and Roof bars. The OHE supply collected by panto is taken to the main transformer through roof bars, DJ and roof-bushing bar. For isolating the panto PT1 & PT2 cot

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out cocs are provided. PT1 cot out coc is provided in Cab1 center locker and PT2 cot out coc is provided in Cab2 back panel.

9.2 PRINCIPLE: Basically, compressed air raises the pantograph and lowering springs of servomotor lower the pantograph. The sole function of air is to cancel the lowering effort of the springs (Servomotor) and it has no direct effect on the pantograph. When the pantograph is working and the air pressure is maintained in the servomotor, the piston is kept forward and the articulated system is entirely free to keep panto in raised position only. Therefore, It absorbs freely all the oscillations of the contact wire. The equipment lowers by itself when pressure drops below 3 to 3.5 Kg/cm². All parts of panto are alive and used as conductors. The current collection is made on the frame with shunts fitted at all moving points.

Minimum air pressure to raise panto: 4.5Kg/cm2Nominal pressure: 7Kg/cm2Rising time: 6 - 10 secLowering time: 10 sec or belowRated current: 400 Amps

9.3 RAISING: Air is admitted to servomotor cylinder. The piston compressed the holding down springs and displaces the slotted link. This permits the rotation of the horizontal spindle under the action of up springs. The pantograph rises until the collector plate reaches the catenary. The articulated system then stops and piston complete its stroke. From this point onwards the air motor plays no further part and piston remains stationary during normal operation. The pin of the horizontal spindle is permitted to move freely in the slot of the control link. The panto operates purely on the up springs, the design is such as to permit free movement of the articulated system throughout full distance of its raise and fall.

9.4 LOWERING: Opening of the control cylinder to atmosphere causes piston to return under the force of holding down springs slotted rod presses on the pin of the horizontal spindle thereby lowering the articulated system.

The throttle valve allows the adjustments of the lowering and raising steps of the pantograph. The raising speed depends up on only on the gauged hole. The lowering takes place in two stages the first on quick stage and second on the slow stage. Pantograph maybe raised or lowered from cabin by any of the following methods.

a) Air raised gravity lowered.

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b) Air raised spring lowered.

c) Spring raised air lowered.

9.5 REASONS FOR USING THE REAR PANTO:

1. It gives the smooth passage for the panto.2. It avoids the spark coming from the Loco Pilots desk.3. In case if any damage occurs to the panto, the damaged parts of the panto will be

thrown out of the train.4. At the time of entering into the unwired track or any defect is noticed in OHE, if DJ could

not be opened while approaching neutral sections, there is possibility for the Loco Pilots to lower the panto which can avoid panto entanglement.

Figure 11: Panto pneumatic circuit

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CHAPTER 10: MOH SECTION

10.1 INTRODUCTION: MOH section deals with the major overall of the engine. The engine as per its schedule (18 Months) is brought to its home shed for its maintenance and is first reported to the MOH section. This section then identifies the fault part and then refer it to the section concerning to it. For example if the traction motor is giving a fault then it will be given to the traction motor section for its repairing.

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CHAPTER 11: PNEUMATIC SECTION

Pneumatic section is the mechanical braking system in the locomotives which is achieved by the compressed air in the cylinder. The pressurized air comes from an air compressor in the locomotive and is sent from car to car by a train line made up of pipes beneath each car and hoses between cars. The principle problem with the straight air braking system is that any separation between hoses and pipes causes loss of air pressure and hence the loss of the force

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applying the brakes. This could easily cause a runaway train. Straight air brakes are still being used n the locomotives although as a dual circuit system, usually with each bogie having its own circuit. There are two types of brakes used in LOCO:

AIR BRAKES: The compressed air is used for obtaining brake application. The brake pipe and feed pipe run throughout the length of the coach. Brake pipe and feed pipe on consecutive coaches in the train are coupled to one another by means of respective hose couplings to form a continuous air passage from the locomotive to the rear end of the train. The compressed air is supplied to the brake pipe and feed pipe from the locomotive. The magnitude of braking force increases in steps with the corresponding reduction in brake pipe pressure and vice-versa.

VACCUM BRAKES: The vacuum brake system derives its brake force from the atmospheric pressure acting on the lower side of the piston in the vacuum brake cylinder while a vacuum is maintained above the piston. The train pipe runs throughout the length of the coach and connected with consecutive coaches by hose coupling. The vacuum is created in the train pipe and the vacuum cylinder by the ejector or exhauster mounted on the locomotive.

WORKING: Application of loco brake along with formation brakes is called proportional working. When BP pressure is dropped, C3W valve senses the droppage of BP pressure. C3W valve senses when BP drops 0.6kg/cm2 within 6 seconds. When BP drops in loco, C3W acts and it takes proportionate MR4 pressure and passes via 2kg/cm2 limiting valve and acts on VEF (m). Now VEF (m) admits MR4 pressure to C2B valve through F1 selector valve and double check valve. C2B valve now takes MR4 pressure and send to loco brake cylinders when both trucks bogie isolation cocs are in open position. To isolate loco brake application by A9, press PVEF. Now VEF (E) energizes and admits MR4 pressure to VEF (M). Now VEF (M) exhaust port is connected to C2B. The existing pressure from C2B to VEF (M) becomes ‘0’. When there is no actuation on C2B, the brake cylinder pipe line is connected to C2B exhaust port there by the brake cylinder pressure become ‘0’ and brakes are released.

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CHAPTER 12: POWER SECTION

This section deals with the power instruments used in the locomotive such as VCB, oils in the transformers test etc.

TRANSFORMER: Transformer is a static device used for stepping up or stepping down the AC supply voltage (In traction is intended for stepping down from OHE catenary supply of 25 KV to 1750 V and 380 V). This is located in the HT compartment of the locomotive. It is an oil immersed type with forced circulation cooling. The power from OHE collected through pantograph and circuit breaker is supplied to the regulating winding of the Auto transformer. Arrangement of the various windings on the limbs of transformer is as shown in the diagram. The transformer has 3 limbs. The first limb carries the windings of auto transformer regulating winding. This winding is provided with 32 taps. The wining is suitable for giving a rated output of 3640 KVA. The tapings taken out are connected to tap changer. The tap changer is driven by SMGR driven by air motor. The air motor can be operated even with minimum air pressure of 3 kg/cm2. Another auxiliary windings (TFWA) is intended for supplying single phase 50 HZ, 380 ± 22.5% volts supply to ARNO converter. The coil is suitable for 180 KVA load. The primary winding (A0 – A34) and secondary winding (a3 – a4 and a5 – a6) are carried on limb 2 and limb 3. The primary winding consists of two groups in series on limbs 2 and 3. The secondary winding consists of four groups and occupies symmetrical group positions on limbs 2 and 3 in relation to primary groups. All the coils are disc (or pan cake) type since tap changer oil is subjected to heavy duty (i.e. arcing during movement of contact roller on contact segments) it requires frequent changing and maintenance as compared to transformer oil. So the transformer oil is sealed off from tap changer oil such as to facilitate drawing out of tap changer oil alone for maintenance purpose cooler is (MVRH) mounted on the transformer cover oil circuit pipe line connections need not be removed for maintenance. Recent developments in some transformers are SF6 gas cooling is used. The transformer magnetic circuit consists of laminated magnetic cores interleaved to form the three limbs. H.V. circuit is connected to DJ through condenser type bushing. The upper bushing is mounted on the roof of the locomotive. The lower bushing is fitted on the cover of transformer and middle part of bushing (in between) is screwed to the bottom bushing. The secondary winding (L.T.) is connected to the external circuit taken out of transformer through 4 bushings and are also mounted on the cover of transformer. Oil conservator is situated above the transformer. The pipe leading to it is serving as a safety valve having an oil over flow chamber above it. The oil over flow chamber has a discharge pipe to lead the blown out oil down underneath the locomotive body. This complete system thus acts as a pressure relief device. The oil pump and

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the cooler are connected to the conservator by a venting pipe. Air does not come in contact with the oil directly. The moisture in the air entering breather is completely absorbed by silica gel acting as an air dryer.

VACCUM CIRCUIT BREAKER: Vacuum circuit breakers are replacing the air blast circuit breakers used on electric Locos/EMU'S due to following advantages.1. Less Maintenance2. Greater Safety3. Greater Reliability4. Simplified Control5. Noiseless Operation

CONSTRUCTION: The main switching unit consists of two vacuum interrupters connected in series and are mounted in the Horizontal support insulator. Each interrupter houses a pair of contacts. The interrupters operating rods are connected to a pneumatic dual piston. Operating mechanism is mounted in the main cradle between the interrupters, which closes the contacts by the application of air supply. The contacts are held normally open by heavy-duty springs. When actuating rod through the crank pins, operates auxiliary DJ interlock unit. It is fixed to the spring plate. The relay valve body is bolted to one side of the air cylinder. The control air pipe and main air pipe, which are made up of special nylon, are routed between the relay valve and the base of the circuit breaker inside the insulator. The regulated and filtered air pressure of 5 Kgs/cm2 is supplied from air reservoir QPDJ setting is kept at cut in 4.65 Kgs/cm2 and cut out 4.0 Kgs/cm2.

OPERATION: When the magnet valve is energized, control air is admitted to the bottom chamber of the air relay valve and pushes the puppet valve upwards to allow operating air through main pipeline in to the cylinder via 2mm diameter choke. The operating air in the cylinder piston moves outwards against the pressure of springs, thus closing the contacts in those interrupters. Air cylinder has small and large ports. When the magnetic valve is energized air enters in to the cylinders first the small port and then at through energized touch with each other by the large port, thus the contacts are fully closed. When the magnet valve is de-energized the cylinder exhausts to atmosphere thus causing the piston to accelerate rapidly inwards by the face of springs.

POTENTIAL TRANSFORMER: The primary voltage transformer is situated on the converter roof hatch and attached to the pantograph via the roofline. The primary voltage transformer reduces the catenary voltage, approximately 25 kV, to 200 volts AC. A resistor is placed across

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the primary voltage transformer to provide a reference load. The output signal is used in three ways;

1) Main converter electronics = 4 volt AC2) Catenary voltmeters on the driver’s console = 10 volt DC3) Minimum voltage relay.When panto is raised this potential transformer fed to U meter and U meter shows the

OHE supply in drivers cab. As such we can have an idea of availability of OHE supply before closing DJ and also idea of rising of panto. However our responsibility of seeing panto is not finished, we have to check the condition of panto physically.

Figure 12: Traction power circuit

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HARMONIC FILTER: Line harmonic filter is connected with primary winding of main transformer which consists of resistances and capacitor. This harmonic filter reduces/suppressed the high frequency harmonics to avoid disturbances in signaling. If the harmonic filter gets bypassed by the system, the speed of the loco / train will be automatically restricted up to max 40 KMPH by CE.

BATTERY: In ABB loco NiCD Battery is used. There are total 78 cells in the batteries which are placed in 2 boxes at either side of the locomotive. Each box contains 39 cells and each battery has 3 cells. Capacity of battery is 199 A-H and output is 110 V. To charge the battery, one battery charger is provided with circuit breaker no. 110 situated in SB2. Main switch for battery is 112 which is placed in a box provided near battery box no. 2. For control circuit supply 1 MCB no. 112.1 is provided in SB2. To show the battery voltage UBA is provided in either cab.

Note:-1. If battery voltage is 92 V for more than 30 seconds, P-2 Fault will appear on the screen.2. If charging current is reduced by 10 A, P-2 fault will appear on screen.3. If battery voltage is reduced below 82 V, P-1 message with shutdown of loco will appear.4. If cab is activated and panto is lowered than 10 minutes CE will switch off automatically.5. Loco CE get power supply directly from battery and can supply upto maximum 5 hours.6. For machine room light power supply is given directly through MCB 327.4.

Technical Specification:Cell model = SBL-199Cell type = Nickel/CadmiumNumber of cells per battery = 3Number of batteries per battery box = 13Number of battery boxes = 2Total nominal capacity = 199 AhNominal voltage of each cell = 1.4 VTotal battery voltage = 1.4 x 3 x 26 =110 V

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CHAPTER 13: ELECTRONICS SECTIONThis section consist of the electronics instruments such as CHBA (Battery Charger), AC damping panel, static converter, RSI block, SL block, SR power converter etc.STATIC BATTERY CHARGER (CHBA): Battery charger is a static device for charging the batteries as well as to maintain the control circuit in energized condition. After closing DJ, it receives 380V supply from ARNO. The charger has a step down transformer to step down 380 V ac. into 110V AC and further converted to 110V DC supply by means of a bridge rectifier. The output of CHBA (110V DC) is fed to batteries for charging as well as for energizing control circuit. When the charger is kept in working condition, relay QV-61 will energize and lamp "LSCHBA" extinguishes by opening it’s normally closed I/L in signaling circuit. An Ammeter is provided on battery charger to indicate the rate of charging. A voltmeter UBA along with ZUBA is provided to measure the battery voltage and charger voltage. UBA indicates battery voltage only when DJ is in open or HCHBA is placed on zero. A fuse tester ECC is provided with lamp LECC across the batteries to check the condition of the spare fuse available in TB panel.

180 kVA STATIC CONVERTER: System Description: The converter generates 415V, 3-phase, 50Hz output from 760V / 830V, 1 phase, 50Hz input which is available from the main locomotive transformer. General schematic of the converter is shown in below figure.

Converter schematic diagram: The static converter is made using a half controlled single phase bridge rectifier at the input, a DC link filter and a three phase IGBT based PWM inverter. All

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functions of the converter are controlled through 32 bits digital signal processor (DSP) together with a EPLD & host of digital gates and analog amplifiers.

This converter consists of the following sub modules:

Rectifier Circuit Overvoltage chopper Inverter circuit Gate drive circuit Controller circuit

TRACTION CONVERTERS (SR): Traction converter converts single-phase 25 KV AC supply into 3 phase AC, with Variable Voltage (max 2180 V) and frequency (from 65 to 132 Hz) while traction mode and fed it to traction motor group -1. As such there are two traction converter i.e. Traction converter-1 for TM 1-2-3 and Traction converter-2 for TM 4-5-6.( In case of WAP-5 , traction converter-1 for TM 1-2 and Traction converter-2 for TM-3-4) While electrical braking the traction motor works as a generator and fed generated 3-phase supply to Traction converter. This converter now act in reverse manner i.e. it converts 3 phase AC supply into single phase AC supply and fed it to Transformer. Further main transformer steps up this supply and fed back to OHE. In this way 3 phase loco works as a small powerhouse, which generate supply and share the load by feeding it back to OHE. SR is cooled by two separate oil cooling unit. The traction converter has three main sub parts:

1) Line Converter 2) Intermediate DC link and

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3) Drive converter. One spy glass is provided on each SR to check the oil level.

SILICON RECTIFIERS (RSI BLOCK): The main rectifier consists of two identical cubicles. Each cubicle houses the diodes, Fan, bridges-fuse etc. The output of each rectifier feeds a group of three traction motors. Each cubicle is provided with 6 bridges connected in parallel and protected by bridge fuses. In the event of failure of any of the bridges, the bridge fuse blows, triggering in turn the signaling fuse which lights up a signal lamp LSRSI on the driver’s desk. Each cubicle is fitted with one axial flow blower driven by 3 ph motor (MVSI 1-2)No. Of cubicles per loco 2Rated current 3300 AmpsMax. Starting current 4050 AmpsNo Load rated voltage at 22.5 KV 750v dcConnection BridgeNo. Of bridges 6 per cubicleNo. Of Diodes 4 per bridge

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CHAPTER 14: WHEEL SECTION

Generally in all locomotives solid wheel is used due to the needs of increase traffic, higher speed, steeper gradients all of which demand stronger braking. The profiles of new tyre / wheels are as follows:

Diameter New 1092mmWorn 1016mm

Minimum width of tyre Coupled wheel 133mmOther than coupled wheel 127mm

Thickness of tyre flanges Thick flanges 32mmStandard flanges 28mmThin flanges 18mmThread 63.5mmDistance between wheel set

1596 ± 0.5mm

Some locos are provided with renewable steel tyres and tyre as per specification IRSRIS- 64 oil quenched with tensile strength of 100-110 Kg/cm2. Other locos are provided with solid wheel disc conforming to specification, IRS M2-65 and IS 1030-1962.The diameter of new wheel size of WAG5, WAM4, and WAP type locomotives is 1092 mm. The condemning diameter is 1016 mm.

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CHAPTER 15: LAYOUTS OF LOCOMOTIVE

Figure 13:Bogie Layout

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Figure 14: Roof layout

Figure 15: Front connections

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Figure 16: Cab layout

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Figure 17: WAG 9/WAP7 machine room layout

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Figure 18: WAP 5 machine room layout

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