Electrical Loco Shed, Ghaziabad
Name : Shreyashkar Singh
ABES engineering college
> Electric Loco Shed was set in 1976 by Railway
Electrification Organisation (8910 SQ. MTRS).
> It’s main purpose is of maintenance of
WAP1,WAP4,WAP5,WAP7 ,WAG5, WAM4
Rs. 1.5 (IN CRORES)
PRESENT LOCO HOLDING
Driving forward of vehicle is called traction and the system,
which employ this type of mechanism is called as traction
Classified broadly into two groups namely:
1. Non Electric Traction System.
2. Electric Traction System.
>Electric Traction means a Locomotion in which the
driving force is obtained from electric motors.
>For Traction purpose 3-phase induction motor and DC
series motor are used and both have high starting torque
provide high speed acceleration.
TYPES OF ELECTRIC TRACTION SYSTEM
DC traction units uses direct current drawn from
DC traction units uses 600v-750v DC voltage range .
The low-voltage,series wound,direct current motor is
well suited to railroad traction,being simple to construct
and easy to control.
AC Traction units draw alternating current from an
Typical voltages used are-
15kV /25kV AC,50Hz
Fewer substations are required and the lighter overhead
current supply wire can be used.
Reduced capital cost of electrification
Components of an ac locomotive
CATENARY:- This is the Over head Wire of Special
Cross section of area.
PANTOGRAPH:- This is a device used for collecting
current from the catenary.
CIRCUIT BREAKER:- To disconnect the engine from the
line side in case of some fault.
RECTIFIERS:- Conversion of AC power into DC power.
SMOOTHING REACTORS:- Any ripple found on the
output side of the rectifier are eliminated bythis fitted after
TRANSFORMER:- It is installed in locomotive for step
down the voltage according to the requirement of motor.
A pantograph is a device that collects electric current from
overhead lines for electric trains or trams.
It is spring loaded and pushes a contact shoe up against the
contact wire to draw the electricity needed to run the train.
Pantographs are typically operated by compressed air from
the vehicle's braking system, either to raise the unit and hold
it against the conductor .
Mainly two types of brakes are
1. Air Brake System
2. Regenerative Brake System.
1. Air Brake System
This braking systems use compressed air as the
force to push blocks on to wheels or pads on to discs.
In this system three main positions are used in
controlling the loco.
I. Application Position
II. Release Position
III. Lap Position
2. Regenerative Brake system
During braking, the traction motor connections are altered
to turn them into electrical generators.
The motor fields are connected across the main traction
generator and the motor armatures are connected across
The rolling locomotive or multiple unit wheels turn the
motor armatures, and the motors act as generators, either
sending the generated current back into the supply.
In electric locos mainly squirrel
cage, 3-phase Induction Motor
Nose suspended, axle hung
type traction motor is used.
Nose-Suspended type traction
Motor is mounted in the bogie
frame supported partially by
the axle which it drove and
partially by the bogie frame.
The motor case is provided
with a "nose" which rested on
a bracket fixed to the frame of
Wheels are manufactured of cast
Railway wheels sit on the rails
the flanges should not touch the
The wheel tire is coned .
Rail head slightly curved as
shown in the diagram.
High power-to weight ratio.
Higher limit of speed
Higher hauling capability
No carbon emission
Less noise pollution
Maintenance cost is 50% of that for steam engine.
Steam engine requires two hours for heat up whereas
electric engine start within moment.
High torque motor are used in electric traction.
ADVANTAGE OF ELECRICAL LOCO
Significant capital cost of electrification.
Maintenance cost is high.
Overhead wires further limit the clearance in tunnel.
Railway traction need immune power, with no cuts.