Global Institute of Science Technology

ICARE Complex, Hatiberia, Purba Medinipur, Haldia

Department of Electrical Engineering
Electric Traction Lab (5th SEM, EE)

EXPERIMENT NO: 07
Title:
Visit to\ watching video on railway station (for signaling and train lighting) and writing a report on
visit.

Objective:
To visit to\ watching video on railway station (for signaling and train lighting) and writing a report
on visit.

Introduction:
Train lighting by electricity was first introduced on India Railways in 1987.Supply of electricity in
trains is required primarily for lighting-a necessity; for fans-an amenity, and for air conditioning-now a
luxury, but as it usually happens the luxury of today is the necessity of tomorrow. Besides this electricity
is also used in the kitchen cars for refrigerators and for cooking purposes.

System of train lightening:

Power requirement of a train can be met with in following different ways:
i. By axel driving generators in conjunction with batteries or
ii. By a separate generator driven either by stream turbine mounted on the locomotive or by diesel
prime mover installed either on the underframe of the coach or in separate power van. Latter
solution is adopted in case of heavy power requirement and is technically called end of generation.

Single battery system:

This system, shown in Figure: 1 is the cheapest among all axle generation system. In this system
only one set of battery is used. When the generator is driven above certain speed auto cut in switch will
operate and dynamo will be supplying the light load as well as charging the batteries through the lamp
resistance. When speed falls below cut out value, auto card in switch will disconnect that dynamo and the
lamp resistance will be short circuited. Now batteries will be supplying the load directly. The main
drawback of this system is that the insertion and cutting out of the resistance is invariably attended by
lamp flicker. However, by the employment of automatic voltage regulator in conjunction with shunt
dynamo, this defect has been overcome.
 Figure 1: Single Battery System.

Double Battery Parallel Block System:

In standard train assemblies, there are coaches without generating equipment as well as coaches
with generating equipment. In parallel block system of lightning, allthe dynamos and batteries of fully
equipped coaches work in parallel and supply the light and fan load of all the coaches including non-
equipped coaches of the train through five roof wires running throughout the train. The coach roof wires
are connected through special couplers so that train can be broken and remade in any way as desired. In
double battery system, half of the batteries, connected directly across the dynamo terminals, get charged
and the other half of the batteries are connected to the lamp loads and also dynamo terminals through
lamp resistance. The value of lamp resistance is such that this battery just floats across the lighting mains
and helps to keep the voltage steady across the lamp terminals. This batter is, therefore, also called
regulating battery.
 Principal Equipment of Double Battery System:
Principal components of the double battery system as observed from Figure:2are:
1) Coach wiring including intervehicular coupler and junction boxes.
2) Dynamo
3) Switchgear consisting of
a. Auto cut in and cut out switch.
b. Over voltage and over charged relays.
c. Battery change over switch.
d. Load switch for the remote control of lights
4) Lamp resistance
5) Set of accumulators.

Figure 2: Double Battery System.

 TRAIN SIGNALS
Introduction:
The signals prescribed in these rules shall be used for controlling the movement of trains in all cases
in which exceptions are not allowed by approved special instructions.
 “Aspect of a signal” means the appearance (position of arm or colour of light) of a fixed signal as
seen by the Loco Pilot of a train approaching it from the direction (Up or Down) to which it refers.
 “Indication of a signal” means the information or meaning conveyed by the aspect of a signal.
 “In rear of a signal” means any position on that portion of the line leading up to the signal, in the
direction to which the signal refers to the line. The Loco Pilot of a train approaching the signal is said
to be “in rear of the signal”, as long as he has not passed the signal.
 “In advance of a signal” means any position on that portion of the line beyond the signal, as viewed
from the direction in which the signal refers to the line. The Loco Pilot of an approaching train is
said to be “in advance of the signal”, after he has passed the signal. This portion of the line is
protected by the signal, if it is a Stop signal.

Kinds of signals:
The signals to be used for controlling the movement of trains shall be-
(a) fixed signals,
(b) hand signals,
(c) detonating signals, and
(d) flare signals.
Use of night signals by day:
The signals prescribed in these rules for use by night shall also be used by day in tunnels and in
thick, foggy or tempestuous weather impairing visibility.

Fixed signals:
 Except under approved special instructions, all railways shall be equipped with fixed signals as
prescribed in these rules.
 The aspects of a semaphore signal shall be displayed by the position of the arm by day and by a light
or lights by night.
 The aspects of a colour light and position light signal both by day and by night shall be the same and
shall be displayed by fixed light or lights.
 The arm of a semaphore signal shall work in-
a. the lower quadrant in two-aspect signalling, and
b. the upper quadrant in manually operated multiple-aspect signalling.
 The “off” position of a semaphore signal shall be displayed by day by the inclined position of the
arm from 45o to 600 below the horizontal in case of two-aspect lower quadrant signals, and 450 or
900 above the horizontal in case of multiple-aspect upper quadrant signals.
Warner signals:
 A semaphore Warner signal has a fish-tailed arm.
 A Warner signal is intended to warn a Loco Pilot-
a. of the condition of the block section ahead, or
b. that he is approaching a Stop signal.
 A Warner signal may be placed either-
a. on a post by itself with a fixed green light 1.5 to 2 metres above it by night, or
b. on the same post below the first Stop signal or the last Stop signal.
 When placed in accordance with clause (b) of sub-rule (3), the variable light of the Stop signal shall
take the place of the fixed green light of the Warner signal and the mechanical arrangement shall be
such that the Warner signal cannot be taken “off” while the Stop signal above it is “on”.
  The aspects and indications of a semaphore Warner signal are shown below: -
a. Semaphore Warner signal in Two-Aspect Signalling Territory-on a post by itself
“On” position “Off” position

b. Semaphore Warner signal in Two-Aspect Signalling Territory-below a Stop signal

“On” Position “Off” Position

 The aspects and indications of a colour light Warner signal are shown below:
a. Colour light Warner signal in Two-Aspect Signalling Territory-on a post by itself
“On” Position “Off” Position

b. Colour Light Warner signal in Two-Aspect Signalling Territory-below a Stop signal

“On” position “Off” position

Distant signals:
 A semaphore distant signal has a fish-tailed arm.
 The aspects and indications of a semaphore Distant signal working in the lower quadrant are shown
below: -
  The aspects and indications of a semaphore Distant signal working in the upper quadrant are shown
below: -

 The aspects and indications of a colour light Distant signal are shown below:

 A Distant signal shall be located at an adequate distance in rear of the Stop signal, the aspect of
which it pre-warns.
 Where necessary more than one Distant signal may be provided. In such a case, the outermost signal,
to be located at an adequate distance from the first Stop signal, shall be called the Distant signal and
the other called the Inner Distant signal, with the Distant signal capable of displaying `Attention’ or
`Proceed’ aspect only.

Stop signals:
 A semaphore Stop signal has a Square ended arm.
 The aspects and indications of a semaphore Stop signal working in the lower quadrant are shown
below: -
 The aspects and indications of a semaphore Stop signal working in the upper quadrant are shown
below: -

 The aspects and indications of a colour light Stop signal are shown below: -
a. Colour light Stop signal in Two-Aspect Signalling Territory
”On” position “Off” position

b. Colour light Stop signal in Multiple Three-Aspect Signalling Territory

“On” position “Off” position