SIGNAL AND TELECOMMUNICATION WORKSHOP

INTRODUCTION

ABOUT THE INDUSTRY

The first system for the rail system in India was put forward in 1832. Indian Railways
Industry is the largest Indian public sector undertaking and largest railway system in Asia run
with 12000 trains a day & 63000 route kms of track. Indian Railways has around 7349 railway
stations. It takes up the task of carrying nearly 23 million passengers and 3 million tonnes of
cargo per day. Indian’s railway network is recognized as one of the largest railway systems in the
world under single management. The railway network is also ideal for long-distance travel and
movement of bulk distance travel and movement of bulk commodities, apart from being an
energy efficient and economic mode of conveyance and transport. Indian Railways was the
preferred carrier of automobiles in the country with loading from automobiles traffic growing 16
per cent in 2017-18.

Indian Railways revenues increased at a CAGR OF 5.48 per cent during FY07-FY09 to
US$27.13 billion in FY19. Earnings from the passenger business grew at a CAGR of 5.58 per
cent during FY07-FY19 to reach US$7.30 billion in 2018-19.Frieght revenue rose at a CAGR of
5.84 per cent during FY07-FY19 to reach US$18.20 billion in 2018-19. India was among the top
exporters of railways globally, as of 2017. India’s exports of railways have grown at a CAGR OF
27.05 per cent during 2010-2017 to US$303.29 million. Exports of railways in 2018 (up to July
2018) stood at US$278.05

The Indian Railway network is growing at a healthy rate. In the next five years, the Indian
railway market will be the third largest, accounting for 10 per cent of the global market. Indian
Railways, which is one of the country’s biggest employers, can generate one million jobs,
according to Mr.Piyush Goyal, Union Minister for Railways and Coal.
DEPARTMENTS IN INDIAN RAILWAYS

Indian Railways divides its operations into zones, which are further sub-divided into divisions,
each having a divisional headquarters. There are 18 zones and 73 divisions. A typical division
has an average track length of about 15,000. All the departments of Indian Railways are listed
below:

1. Engineering Department
2. Mechanical Engineering department (General)
3. Electrical Engineering department(General)
4. Electrical Engineering department(Traction Distribution)
5. Electrical Engineering department (Operations)
6. Signaling & Telecommunication Engineering Department
7. Operating Traffic (Transportation) Department
8. Commercial Department
9. Medical Department
10. Safety Department
11. Stores Department
12. Accounts Department
13. Personnel Department
14. Security Department
15. Managing Department
16. Medical Department
 SIGNAL&TELECOM WORKSHOP/PODANUR

HISTORY

S&T Workshop, which was functioning as a small Repair Unit at Golden Rock/
Thiruchirappalli was shifted to Podanur on 09.04.1958 with a staff strength of 60.

Initially, this Workshop was engaged in the manufacture of various Mechanical Signaling
Items. i.e., Control Panels, Lever Frames and Lever Lock Circuit Controllers.

Besides this, Overhauling and Repair of Reversers, Single Line Block Instruments, Control
Phones and Control Selectors were also being carried out.

There was also a small laboratory attached to this workshop to carry out developmental activities
mainly in Telecom sector. Since then, this Workshop has progressed in leaps & bounds and has
become a pioneer in the Manufacture of Signaling Equipments in the Indian Railways.

The major shift in the Workshop’s activities from Repair and Overhauling of the Signal &
Telecommunication Equipments to the manufacturing sphere happened over the years from 1968
to 1977 with the expansion of infrastructure, Single Line Token Less Block Instrument, Combined
Type GRS 5E Point Machine, etc.

In the year 1978, this Workshop started production of Electronic Axle Counters and in the year
1995-96, this Workshop started the production of Universal Axle Counters and IRS Rotory
Locking Type Point Machine as per the design RDSO, LUCKNOW. Now, this Workshop is set to
manufacture Single Section Digital Axle Counters and Universal Fail Safe Block Interfaces also
from this year.
AWARDS & ACHIEVEMENTS

ISO 9001: 2000 Certified Unit

This Workshop was awarded ISO 9002/1994 certification during 1998. This certification has
been upgraded to ISO 9001: 2000 version.

Achievements

The out-turn of the workshop was Rs. 30.95 Crores for the year 2005-06 and Rs. 25.02 crores
in 2006-07(upto 31.12.06). Enhanced out turn is targeted in the coming years.

PRODUCTION PROFILE

Important products manufactured in this workshop are Q-series Relays, IRS Point Machines,
TLB Instruments, and Universal Axle Counters, Double line Block Instruments, Polarised Relays
and Control Panels.

DEVELOPMENTAL ACTIVITIES

This workshop has developed High Thrust Point Machine 220 mm Stroke with clamp type
locking and Special type Relays QTA2 and QT2.

COMPUTERIZATION AND NETWORKING

The following activities of Production Control Organization have been computerized.

for all manufacturing items.

– inspection of inward items.

SIGNAL AND TELECOMMUNICATION DEPARTMENT

Signal and Telecommunication Department is responsible for installation and maintenance of

Signaling system essential for the safe & speedy movement of trains and Telecommunication
systems required for the effective utilization of the large fleet of locomotives and other rolling
stock and track as well as for the administration of the vast Railway Network. Telecommunication
is a vital infrastructure for managing any transportation network. Indian Railway has an in-house
Railway Telecommunication Network for managing Train operations and staff management and
to offer Passenger Amenities. In terms of the sophistication in Signaling and Telecommunication
installations, Southern Railway occupies the pride of place among the various Indian Railway
systems.

S&T Department consists of both administrative and project offices with a workshop at
Podanur. Organizational setup and duties of officers and other salient features of the department
are detailed below.

SALIENT FEATURES

SIGNALLING

 Multiple Aspect Color Light Signaling (MACL)

Mechanical signals of Semaphore type are progressively replaced by Electrical signalling with
Multiple Aspect Colour Signals (MACL). MACL signals have better visibility, quick operation
and less maintenance.

 Route Relay Interlocking (RRI) and Central Control Panels in signal control system

By mere operations of knobs and route buttons, routes are set automatically and signals are cleared
with absolute safety. The entire station is track circuited. Points and signals are operated by
individual knobs/slides in small yards.

 Panel Interlocking system

Unlike Route relay interlocking, in panel interlocking points and signals are operated
individually. This is being adopted in smaller wayside stations.
  Solid State Interlocking

As a technological development, the solid state with electronics system having software
programming, solid-state interlocking signalling control system is being now inducted to achieve
economy and flexibility. This sophisticated microprocessor based interlocking system works
through Microprocessor devices and software programming. In this system there is less number of
relays, and alterations/additions in the yard is possible without much extra wiring. This system
adopts the usage of latest CENLEC standard of software validation.

 Automatic Block Signalling with Continuous Track Circuiting

Automatic Block signalling systems are mostly used when the train traffic become more
congested and busy, especially in suburban area and to increase line capacity. This eliminates
block working and trains are signalled automatically without much dependence on human element.
This ensures train safety, speed and also detects any rail discontinuity.

 Token less Block working

In the absolute block system in single line, Token Block instruments are used. The token will
be handed over to the driver of train after granting line clear to enter in the Block section. The
process of handing over of token at every station is time consuming and laborious resulting in
token missing. The system of token less block working helps to increase line capacity on single
line sections.

 Audio Frequency Track Circuits (AFTC)

Southern Railway has the distinction of introducing Audio Frequency Track Circuit for the first
time in the Indian Railway system in 1994-95.

As the conventional DC track circuits are found vulnerable to the interference of currents
generated by the thyristor/Chopper controlled locomotives, joint less Audio Frequency track
circuits have been found to be the solution in such sections. The AFTC does not require insulated
joints and can work for longer lengths and is suitable for AC and DC electrified areas. These track
circuits are more reliable because failures due to block joint shorting are avoided, due to non-
availability of joint and the train running is very smooth.
  LED signals for colour light signalling (LED)

In the colour light signals light aspects of mechanical signals are lit by incandescent bulbs.
These bulbs have limited hours of working and get fused due to ageing and voltage fluctuations.
The bulbs have to be replaced frequently. As an improvement, LED lit signals are now introduced.
LED signals are having longer life and better visibility. This type of signal has enhanced the
reliability by reducing the incidences of signal lamp fusing. It also affords good visibility to the
drivers and more signals are likely to be converted to LED signals.

 Replacement of over aged assets

Over aged signalling assets are normally to be replaced after a codal life of 25 years. Most of
the signal systems are obsolete mechanical type and no spares are now available in the trade. The
mechanical signals are operated from the mechanical lever frame from cabin. Most of the
signalling systems have become over-due for replacement. With the sanction of the Special
Railway Safety Fund the over aged assets are being replaced on priority basis.

 Track circuiting

Track circuit detects the presence or absence of the train on the track. This is the backbone of
the signalling system. This ensures complete safety to the train in case of human failure. Due to
high utilisation of the track capacity, this ensures safe, speedy and punctual movement for train
services.

 Level crossing

The unmanned gates are taken up for manning where telephone facilities are provided from the
nearest station so that gate will be closed well in advance before the train approaches the manned
gates. LC gates are being taken up for interlocking on the basis of train vehicle units (TVUs) to
ensure safety for both trains and road users.

 Train protection & Warning system

This system will give information to the driver to regulate the train speed depending upon the
aspect of the signal in advance. In case, the driver fails to do so, the train will be automatically
stopped by applying brake without the intervention of the driver. This
Ensures that whenever any train stops on the track, the following trains stop automatically, thus
ensuring safety.

 Train Actuated Warning Device

Whenever train approaches an unmanned level crossing, a hooters sounds giving warning to
the road users well in advance about the approach of the train thereby avoiding any accident.

 Networking of Data Loggers

This is a modern equipment used for monitoring the operation of important functions like Track
circuits, Points, Signals, Battery chargers, Batteries etc. installed in Panel interlocked/RRI
installations. These are microprocessor-based equipment logging the events of the change of status
of the various functions in field and relay rooms and recording the precise time also. The data
loggers are useful devices for detecting the cases of passing the signal at danger by the driver and
give important clues in case of accidents. The data loggers are also used as predictive maintenance
tools regarding deterioration of the performance of signalling gadgets.

 Integrated Power Supply System (IPS)/ Non-conventional energy sources

With the introduction of more and more modern Electrical Signalling Systems, the dependency
on the power supply becomes more essential. To get reliable power supply, the concept of
Integrated Power Supply (IPS) has been introduced wherein, the different signal power supplies
like 110 AC, 110 VDC, and 24 DC etc. are derived from the common system, which works on
common battery, i.e. DC-DC converter, modular power packs. This IPS will enhance the working
of the signaling system especially in RE (Railway Electrification) area.
TELECOMMUNICATION

1. Train Control Communication

Movement of each and every train is monitored by a controller at the nearest divisional Hqrs.
Facility is also provided to the driver or guard to communicate with divisional Hqrs through
portable telephone which can be easily connected to the overhead line wires which are running
parallel to the track or connected to the Emergency Telephone sockets provided at every KM in
the section where controls are working through underground cables. An emergency portable
telephone is kept in the Guard’s compartment of each and every train.

2. Block Circuits

Running of trains in each section (between any two stations) is controlled by block circuits
through which running of only one train in a section at one time is electrically in addition to oral
confirmation. Overhead lines of Railway or BSNL and underground cables are used for this
purpose.

3. Optical Fibre Cable network

Optical Fibre Cable is laid along the track to provide a reliable and noise free communication.
OFC network is widely used for Railway Control Communication taking advantage of its all long
haul high bandwidth circuit interconnecting Railway Telephone Exchange. Passenger Reservation
System, Unreserved Ticketing System, Network Freight Operating Management system have been
transferred through railway OFC.

In Southern Railway distribution of various media for Telecommunication is as follows 1. OFC

and RE quad cable in Electrified sections 2. OFC and 4/6 quad cable 3. Only OFC. 4. Railway
owned overhead line. 5. Rented overhead line/ channels/ bandwidth from BSNL

4. Railway Telephone Network

There is an in-house Railway Telephone Network connecting all-important offices, officials,

Way stations, Divisional Headquarters & Zonal Head Quarters. Railway telephones exchanges
are inter-connected through Railway OFC network, Railway Microwave network and are
supported by rented BSNL channels as stand by.
 5. Railway Microwave Communication Network

In Southern Railway telecom network is supported by Railway Owned MW network using state
of the art technology (Digital Microwave System). MW network is spread over Chennai-
Jolarpettai, Erode – Palghat, Chennai - Tiruchchirappalli, Madurai - Palghat covering all divisional
headquarters, mostly along the tracks

6. Wireless communication System

Driver, Guard, Supervisors & officers of permanent way, Mechanical, Electrical and Signal &
Telecom departments are provided with 5 watts hand held walkie-talkies, which can be used to
establish communication between moving train & adjacent stations. Every railway station is
provided with 25 watts VHF set for this purpose.

7. Data network

There is an exclusive PRS network connecting Chennai and all the PRS centers of Southern
Railway and other Metros. The centers are connected either through Railway OFC network or
hired channels from BSNL. Similarly there is a Freight Operating Management System network
for monitoring the movement of freight transport. Coach Operation Information System is a
network for coach management and this is under implementation.

8. Passenger Amenities

Safety, security and comfortable journey of the passengers are the aims of Railways in train
operation. To meet this objective, the following facilities have been provided in almost all-
important stations.

9. Voice Recorder

Train operation information between controllers at Divisional headquarters and way stations
are normally passed through control circuits. All such conversations between section controller
and station Master are recorded at control office, which can be used for train management at any
time of investigation in case of any accident/mishap.
 10. Rail net

Railway has its own data network for management purpose called “RAILNET”. This is widely
used for file transfer, e-mail and public information. Public can visit site www.gov.railnet.in. This
network spreads through entire Railway system connecting divisional headquarters, Zonal
headquarters, workshops and hospitals.

11. Disaster Management

Telecom plays a vital role in Disaster Management. To meet the requirement of Disaster
Management a universal number is provided at all control offices which can be accessed from any
part of India duly pre fixing the city code. There are Accident Relief Trains and Medical Relief
Vans placed at strategic locations. All such ARTs and MRVs are equipped with mobile
INMARSAT telephones, walkie-talkie sets and public address system. Video conferencing
equipments and wireless satellite based modems are also being added.

12. Video conferencing

Video conferencing facilities are available in divisional headquarters, zonal headquarters and
Railway board, for administrative purpose.

13. Tele Medicine

A wide band connection has been established between Railway Hospital/ Perambur, Railway
Hospital/Golden Rock and with major Railway hospitals in other Zonal Railways. This enables
exchange of expertise opinion between hospitals.

14. Maintenance

Maintenance of all equipments is carried out through the maintenance set up of staff at Divisions,
Way stations and in specialized laboratories. However, since the telecom technology is changing
fast, Annual Maintenance Contract through reputed firms wherever necessary is being opted.
Maintenance is carried out as per the schedule drawn up in Telecom Manu
CONCLUSION
The Indian Telecommunications network with 110.01 million connections in the fifth largest in
the world and the second largest among the emerging economies of Asia. Today, it is the fastest
growing market in the world and represents unique opportunities for U.S. companies in the
stagnant global scenario. The total subscribe base, which has grown by 40% in 2005, is expected
to reach 250 million in 2007. According to Broadband Policy 2004, Government of India aims at
9 million broadband connections and 11 million internet connections by 2007. The wireless
subscriber base has jumped from 33.69 million in 2004 to 62.57 million in FY2004-2005, in the
last 3 years, two out of every three new telephone subscribers were wireless subscribers.
Consequently, wireless now accounts for 54.6% of the total telephone subscribers base, as
compared to only 40% in 2003. Wireless subscriber growth in expected to bypass 2.5 million new
subscribers per month by 2007. The wireless technologies currently in use are Global System for
Mobile Communications (GSM) and Code Division Multiple Access (CDMA). There are
primarily 9 GSM and 5 CDMA operators providing mobile services in 19 telecom circles and 4
metro covering 2000 towns across the country.

MAJOR PLAYERS

There are three types of players in telecom services

 State owned companies (BSNL and MTNL)

 Private Indian owned companies (Reliance infocomm, Tata Teleservices)
 Foreign invested companies (Hutchison-Essar, Bharato Tele-Ventures, Escotel, Idea
cellular, BPL Mobile, Spice Communications)

TELECOM POLICY ENVIRONMENT

Indian telecommunications today benefits from among the most enlightened regulation in the
region, and arguably in the world. The sector, sometimes considered the ‘poster-boy for economic
reforms” has been among the chief beneficiaries of the post-1991 liberalisation.

Despite several hiccups along the way, the Telecom Regulatory Authority of India (TRAI), the
independent regular, has earned a reputation for transparency and competence. With the recent
reduction of a major dispute between cellular and faced operators, Indian telecommunications,
already among the most competitive markets in the world appears set to continue growing rapidly.

Rajiv Gandhi proclaimed his intention of “leading India into 21st century,” and carved the
Department of Telecommunication (DOT) out of the Department of Posts and Telegraph,
Succumbing to union pressure, in a compromise, Gandhi created two DOT-owned corporations.

Mahanagar Telephone Nigam Limited (MTNL), to serve Delhi and Bombay, and Videsh Sanchar
Nigam Limited (VSNL), to operate international telecom services. He also introduced private
capital into the manufacturing of telecommunication equipment, which had previously been a DOT
monopoly.

In 1994, the government released its National Telecommunications Policy (NTP-94), which
allowed private fixed operators to take part in the Indian market for the first time(cellular operators
had been allowed into the four largest metropolitan centers in 1992. Under the government’s new
poky, India was divided into 20 circles roughly corresponding to state boundaries, each of which
would contain two fixed operators (including the incumbent), and two mobile operators.