1. INTRODUCTION

Indian Railways is the central government-owned railway company of India, which owns and operates most of the country's rail transport. It is overseen by the Ministry of Railways of the Government of India.

Indian Railways has more than 64,215 kilometers (39,901 mi) of track and 7,083 stations. It has the world's fourth largest railway network after those of the United States, Russia and China. The railways traverse the length and breadth of the country and carry over 30 million passengers and 2.8 million tons of freight daily. It is one of the world's largest commercial or utility employers, with more than 1.6 million employees. As to rolling stock, IR owns over 230,000 (freight) wagons, 60,000 coaches and 9,000 locomotives.

Railways were first introduced to India in 1853. By 1947, the year of India's independence, there were forty-two rail systems. In 1951 the systems were nationalized as one unit, becoming one of the largest networks in the world. IR operates both long distance and suburban rail systems on a multi-gauge network of broad, meters and narrow gauges. It also owns locomotive and coach production facilities.

Indian Railways is a department owned and controlled by the Government of India, via the Ministry of Railways. As of May 2011, the Railway Ministry is headed by Dinesh Trivedi, the Union Minister for Railways, and assisted by two ministers of State for Railways. Indian Railways is administered by the Railway Board, which has a financial commissioner, five members and a chairman.

Railway zones

Indian Railways is divided into zones, which are further sub-divided into divisions. The number of zones in Indian Railways increased from six to eight in 1951, nine in 1952, and finally 17 in 2010. Each zonal railway is made up of a certain number of divisions, each having a divisional headquarters. There are a total of sixty-seven divisions.

15. West Central Jabalpur Jabalpur,Bhopal,Kota16. Western Mumbai Mumbai central, Vadodara, Ratlam, Ahemdabad

North Western Railway

North Western Railway came being on 1st October, 2002. It was carved out of 2 divisions each from Northern and Western Railways. The formation of this zone along with five other new zones was first approved by Railway Board on 16th September, 1996 and foundation stone for this zone was laid on 17th October 1996 by the then Prime Minister Sheri H.D. Dive Gowda at K.P. Singh Stadium, Jaipur. The impetus for formation of New Zone came with the Government of India notification no. 97/E&R/700/1/Notification dated 14.06.2002 wherein it was decided that North Western Railway with its jurisdiction over existing Jaipur and Ajmer divisions of Western Railway and Jodhpur and Bikaner divisions of Northern Railway was to come into effect from 1.10.2002.

Jaipur Division

Jaipur Division – This division was formed after merging parts of BB&CI, Jaipur State Railways and Rajputana Malwa Railway, Jaipur Division serves the states of Rajasthan, Uttar Pradesh and Haryana. Being a predominately passenger earning division (84.92% of its earning is by way of passenger traffic), it deals primarily with cross traffic consisting of fertilizer, cement, oil, salt, food grains, oil seeds, lime

stone and gypsum traffic. Container loading is done from here in bulk. The total no. of stations on this division is 128 and the total no. of trains run is 146. Jaipur station alone deals with 88 BG & 22 MG trains and 35,000 passengers in a day. In order to ensure that the passenger does not face any hardship for reservations the division has at the moment 14 functioning Computerized Passenger Reservation System Centers. The staff strength of this division in all categories is 12007.

2. PRACTICAL TRAINING

We received the scheduled summer practical training, as a part of our curriculum from 18 th May to 15th

July under Divisional Railway Manager, North Western Railway (Indian Railways), Jaipur Division.

The training is divided into four modules-

(1) Microwave and Optical Fiber Communication

(2) Exchange and Telecommunication

(3) Passenger Reservation System

(4) Route Relay Interlocking

All over the world Railway transportation is increasingly used, as this mode of transport is more energy

efficient and environmentally friendly than road transportation. Trains move on steel rail tracks and

wheels of the railway vehicle are also flanged Steel wheels. Hence least friction occurs at the point of

contact between the tracks & wheels. Therefore trains carry more loads resulting in higher traffic

capacity since trains move on specific tracks called rails, their path is to be fully guided and there is no

arrangement of steering. Clear of obstruction as available with road transportation, so there is a need to

provide control on the movement of trains in the form of Railway signals which indicate to the drivers to

stop or move and also the speed at which they can pass a signal. Since the load carried by the trains and

the speed which the trains can attain are high, they need more braking distance before coming to the

stop from full speed. Without signal to be available on the route to constantly guide the driver accidents

will take place due to collisions.

There are basically two purposes achieved by railway signaling

To safety receive and dispatch trains at a station.

To control the movements of trains from one station to another after ensuring that

The track on which this train will move to reach the next station is free from movement of another train

either in the same or opposite direction. Apart from meeting the basic requirement of necessary safety

in train operation, modern railway signaling plays an important role in determining the capacity of a

section .The capacity decides the number of trains that can run on a single day. By proper signaling the

capacity can be increased to a considerable extent without resorting to costlier alternatives.

2. 1 MODULE 1 {MICROWAVE & OPTICAL FIBER COMMUNICATION}

2.1.1 Optical fiber Communication

Optical fiber is a dielectric waveguide or medium in which information (voice, data or video) is

transmitted through a glass or plastic fiber, in the form of light. The basic structure of an optical fiber is

shown in figure 1. It consists of a transparent core with a refractive index n1 surrounded by a

transparent cladding of a slightly less refractive index n2. The refractive index of cladding is less than 1%,

lower than that of core. Typical values for example are a core refractive index of 1.47 and a cladding

index of 1.46. The cladding supports the waveguide structure, protects the core from absorbing surface

contaminants and when adequately thick, substantially reduces the radiation loss to the surrounding air.

Glass core fibers tend to have low loss in comparison with plastic core fibers. Additionally, most of the

fibers are encapsulated in an elastic, abrasion-resistant plastic material which mechanically isolates the

fibers from small geometrical irregularities and distortions.

A thin glass strand designed for light transmission. A single hair-thin fiber is capable of transmitting

trillions of bits per second. In addition to their huge transmission capacity, optical fibers offer many

advantages over electricity and copper wire. Light pulses are not affected by random radiation in the

environment, and their error rate is significantly lower. Fibers allow longer distances to be spanned

before the signal has to be regenerated by expensive "repeaters." Fibers are more secure, because taps

in the line can be detected, and lastly, fiber installation is streamlined due to their dramatically lower

weight and smaller size compared to copper cables.

The optical fiber acts as a low loss, wide bandwidth transmission channel. A light source is required to

emit light signals, which are modulated by the signal data. To enhance the performance of the system, a

spectrally pure light source is required.

Advances in semiconductor laser technology, especially after the invention of double hetero structures

(DH), resulted in stable, efficient, small-sized and compact semiconductor laser diodes (SLDs). Using such

coherent light sources increases the bandwidth of the signal which can be transmitted in a simple

intensity modulated (IM) system .Other modulation methods, such as phase shift keying (PSK) and

frequency-shift keying (FSK), can also be used. These can be achieved either by directly modulating the

injection current to the SLD.

2.1.2 MODULE 1 {MICROWAVE COMMUNICATION}

The international telecommunications system relies on microwave and satellite links for long-distance

international calls. Cable links are increasingly made of optical fibers. The capacity of these links is

enormous. A bundle of optical fibers, no thicker than a finger, can carry 10,000 phone calls – more than

a copper wire as thick as an arm.

Microwaves can be generated by a variety of means, generally divided into two categories: solid state

devices and vacuum-tube based devices. Solid state microwave devices are based on semiconductors

such as silicon or gallium arsenide, and include field-effect transistors (FET's), bipolar junction transistors

(BJT's), Gunn diodes, and IMPATT diodes. Specialized versions of standard transistors have been

developed for higher speeds which are commonly used in microwave applications. Microwave variants

of BJT's include the hetero junction bipolar transistor (HBT), and microwave variants of FET's include the

MESFET, the HEMT (also known as HFET), and LDMOS transistor... Most common applications are within

the 1 to 40 GHz range. Microwave Frequency Bands are defined in the table below:

{RADIO & MICROWAVE EQUIPMENT}

2.2 MODULE 2 {EXCHANGE & TELECOMMUNICATION}

The Program interface is a detailed menu-driven interface for programming the IRIS IVDX. It also

provides access to the diagnostic facilities of the system software. The Programs can be entered through

any video display data terminal. The MCC card of the IRIS IVDX has got two serial ports. The first port on

the top of the card is used for connecting the system to the data terminal for programming.

Access to the Program Interface is restricted to trained and qualified programmers as uncertified

personnel can unknowingly cause serious damage to the communication system database. The Terminal

displays prompts and instructions in English, which are generated by the IRIS IVDX. The programmer can

usually make an entry, skip to the next prompt or exit the programming function. Entries are made using

a standard keyboard and the software supports standard keyboard strokes likes DELETE, BACKSPACE etc.

Entries are displayed as they are keyed in. All the commands are case insensitive. However the

password, which you enter, is case sensitive. Ctrl L can be used for entering the last command again. All

the changes made into the system through the programming interface are real time (i.e. the changes are

made to the system as the command is executed.

IRIS Modules

128 Ports (With inbuilt Power Supply)

256 Ports (8 slots)

480 Ports (15 slots)

992 Ports (31 slots)

1504 Ports (47 slots)

Except 128 ports module, external power source is required for rest of the modules. However

128-port system also can be installed on external power source.

IRIS Cards Description

Main Controller Card - MCC

This Card is the Main Control Card of the system. This card supports maximum 8192 ports.

Peripheral Board Controller Card - PBC

This card is used for communication between the Main shelf and the Peripheral shelves.

Feature Line Card (FLC) :- 32 Port

It is used for giving analog Lines. It is a 32 Port Card. Line Operating Voltage is 48V.

Direct Inward Dialing Card (DID): - 32 Port

This card is used to terminate the level DID trunks. Hardware for this card is same as FLC

Card. Therefore IRIS FLC can work as DID card. Only we have to change its software by

Changing its microcontroller.

Feature Trunk card (FTC): - 24 Port

This card is used to terminate the analog trunk lines. This is a 24 Port Trunk Card.

2.3 MODULE 3 {PASSENGER RAILWAY SYSTEM (PRS)}

INTRODUCTION

The IR carries about 5.5 lakh passengers in Reservation reserved accommodation

Every day.

The computerized Passenger Reservation System (PRS) facilitates booking and

Cancelling of tickets from any of the 4000Terminals (i.e. PRS booking

Windows) all over the country.

These tickets can be booked or cancelled for journeys commencing in any party

Of India and ending in any other part, with travels times as long as 72 hour and

Distances up to several thousands kilometer.

There are mainly 5 servers in INDIA. These are New Delhi , Kolkata, Chennai,

Mumbai & Sikandrabad.

EQUIPMENTS:

The equipment used in PRS is --

Modem Multiplexing Equipment End terminal.

MODEM

Modem are used for communication various computer or between Computer &terminals over ordinary or leased (dedicated) telephone lines. We can use modems to log on to micro, mini, main frame computer for line processing. We can use them to connect two remote computers for data.

How does modem works

The word modem in feed is derived from the words modulate & demodulator. Computer communicates in digital languages while telephone lines communicate in analog language. So an inter mediator required which can communicate both these language .20

Modem transmits information between computer bits by one stream. To Represent a bit (or group of bits), modem modulates the characteristics of the wave that are carried by telephone lines. The rate at which the modem changes these characteristics determines the transmission speed of data transmission .The rate of modem is called bound rate of modem. The bound rate of modem is bits per second. In advance modulation such as quadrature amplitude modulate 4 bits & transmitted it in each band. Thus the speed of the modem transmitting at 600 bands would be 2400 bps.The modems can transmit data in two formats: Asynchronous &

Synchronous. The analog modem switch at each location is connected to analog modems of the main as well as the stand by links. If the main l inks fail less , the switch units at either end switch the user equipment at the stand by link. When the main links get restored, the analog modem switches the user equipment back to main link.

Multiplexing Equipment

There are two type multiplexing equipments for each channel.

The multiplexer used may be of 8-ports or 16-port .The data is get multiplexed at the rate of the 96KBps. The multiplexing is generally of analog type.

End Terminal

The end terminals of system is the station where the tickets to be Printed out .The terminal consists of a computer system with a dot matrix printer. The number of the total end terminal at the station can be increased or decreased according to the multiplexing used.

IVRS (Interactive voice response system)

INTRODUCTION:

The system in which, the information available in the computer is retrieved by the user in the form of voice with the help of the interaction between telephone and computer is known as Interactive Voice Respond System (IVRS).With the help of this system information regarding public reservation; arrival departure of train; fare can be delivered to user when and where it is asked through telephone. Each section control office is having a computer called DATA ENTRY COMPUTER along with dial up/lease line modem which is used for linking the computer of other control offices either directly or through server available at Church Gate . Each control office computer is identified as check / data entry point. Information regarding the running of the train can be registered or checked at every 15 minutes duration.

2.4 MODULE 4 { ROUTE RELAY INTERLOCKING}

This system of Route Relay Interlocking was first installed in India at Basin Bridge Junction and Madras Central Stations of Southern Railway and was designed by the Nippon Signal Co. Ltd., Tokyo, Japan. This was followed by the installations in the suburban stations including

Meter Gauge terminal stations like Bangalore City. Due to the simplicity of the circuits employed and the indigenous manufacture of almost all the components required for the system in the Railway owned Workshops, this system of RRI is popular in Southern Railway and South Central Railway.

SEQUENCE OF OPERATIONS:

The sequence of operation of the equipment is explained with the help of a block diagram Turning the entrance knob and pressing the exit button of a route, energizes the route selection relay (LR), provided that no conflicting route is set. Thus the basic interlocking is ensured at the first stage itself.

The energisation of the route selection relay picks up all the point control relays (WLRs) in that route

depending on the route selected provided that the points are free from track locking and route locking.

The point control relay controls the point machine concerned and sets the points required in the route.

The correct setting and locking of each point is indicated by the point indication relay

(NWKR/RWKR).The route checking relay (UCR) checks that all the points involved in the selected

route are correctly set and locked at the site. It also proves that the route set is for the Signal route

initiated including isolation and overlap. The operation of the route checking relay (UCR) de-energizes

the relevant approach stick relay (ASR) and sectional route locking relays (TLSR/TRSRs) thereby

ensuring that the complete route is locked before the signal is cleared.

The signal Control Relay is energized proving all safety conditions required viz., all tracks, including

overlap are clear, all points, including those in overlap, isolation, are correctly set and locked, relevant

route locking and approach locking relays are de-energized etc.

SEQUENCE OF OPERATIONS

STAGES OF SIGNAL CLEARANCE: -

The stages of Signal Clearance will be as follows:

For clearing a signal, only authorized persons can make operations. This is ensured by

providing a SM key on the control panel. With SM key is ‘IN,’ SM turns signal knob and presses route

push button and releases. This is called route selection. A relay called “LR” will pick up which in turn

operates the points in Route, overlap and isolation to the required position if the point is free to be

operated or the point is not engaged by any other route, and the point zone is not occupied

by train. The relays NWKR/RWKR picks up when points are correctly set and locked at site.

Once if the points in the route are operated, i.e., the route is set and locked. (As per New SEM Para 7.27,

the route is to be checked.) For route checking the relay called UCR picks up. Every signal will have one

route checking relay (UCR) and it ensures NWKR/RWKRs of points in the route, overlap and isolation

etc., and other conditions such as knob reversal by authorized persons etc are incorporated in its

circuit. After checking, the route has to be locked. Route Locking means, holding the point in the route

and overlap in locked condition, after the clearance of signal. A relay called ASR’ is employed for this

purpose. Normally this relay will be in picked up condition. When route is checked i.e. when the UCR

picks up, ASR drops. When ASR drops, another relay called point lock relay (WLR) also drops. When

WLR drops, point cannot be operated. Now the ASR picks up only when the train has arrived on proper

signal with sequential operation of track circuits or if the route is cancelled ensuring back locking,

Indication locks and approach locking. The details of back locking, indication locking and approach

locking etc: have already been discussed in the topic SELECTION CIRCUITS (S5H).

For clearing signal, Signal control relay called HR is energized. For a detail study a 3-Road typical

station layout as shown in Fig.3 is taken and typical circuits are dealt in detail along with explanation,

for the same layout.

• SM’s key inserted and turned to ensure authorized operation (SMR/SMCR/SMPR up)

• Route initiation/selection is done (LRs up) by the authorized person.

• Route setting (operating the points to the required condition. (NWKRs/RWKRs up)

• Route checking (UCR up)

• Route Locking/Over lap locking (ASR/TRSR//TLSR/OVSR down), Electrical locking of

Points. (WLR down)

In addition to the above, for Signal Clearance, the following conditions are also to be satisfied

• The clearance of track in the route & overlap (TPRs up)

• One signal - one train feature (TSR up)

• No cancellation is initiated (JSLR down)

• Route Release Relays have de-energized after the last train movement (UYR1, UYR2

etc., are down) (In Southern Railways UYR1 and UYR2 are called as TSSLR and TPZR

Respectively).

3. CONCLUSION

Engineering students gain theoretical knowledge only through books. Only theoretical

knowledge is not sufficient for absolute mastery in any field. Theoretical knowledge in our

books is not of much use without knowing its practical implementation. It has been experienced

that theoretical knowledge is volatile in nature; however practical knowledge imparts solid

foundation in our mind.

To accomplish this aspect, “RAJASTHAN TECHNICAL UNIVERSITY, KOTA” has included training

for students of B.Tech. III Year of 30 days in our curriculum.

We have covered in this report the history, latest developments in Railway ELECTRONICS (Signal

& Telecommunication) interface as well as related fields. We have studied the various uses of

Electronics in railways like. Microwave and Optical Fiber Communication, Exchange and

Telecommunication, Passenger Reservation System & Route Relay Interlocking.

This report is in fact a summary of, what I have learnt and seen during my training in “North

Western Railway, Jaipur.”

4. BIBLIOGRAPHY

References are taken from the following websites.

www.indianrail.gov.in

www.iriset.ac.in

www.cris.gov.in

www.rdso.gov.in

www.railtel.nic.in

www.google.co.in