Accessories track electrifiction

1. Accessories track electrifiction

2. Outline
1.Definition of track-electrification
2.Accessories of track-electrification
a)Overhead capacitor wire
b)wireConductor rail system
c)Current collector-pantograph

3. Track electrification
• A railway electrification system supplies
electrical energy to railway locomotives and
multiple units so that they can operate
without having an on-board prime mover.
• There are serveral different electrification
system use in out the world.
• Railway electrification has many advantage
but requires heavy capatical expenditure for
installation.

4. Accessories of track electrification
c) current collector-pantograph
• Current collector is a device used for the
collection of current from over head lead supply
system to the locomotive power circuit.
• The various current collectors used in traction
system are :
1.Trolley collector
2.Bow collector
3.Pantograph collector

5. 1.Trolley collector
• A trolley collector is used on tramways and
trolley buses and mounted on the roof of the
vehicle.
• A contact with the overhead wire is made by
means of either a grooved wheel or a sliding
shoe carried at the end of a light trolley pole
attached to the top of vehicle and held in
contact with overhead wire by means of a
spring.
• Trolley collector always operate in trailing
position.

6. •It is employed up to speeds of about
32 km/h as beyond this speed there is
every possibility of wheel jumping off
the trolley wire.

7. 2. Bow collector
• It consists of a light metal strip or bow
pressing against trolley wire and frame work is
mounted on roof of car.strip is made up of soft
material.
• A bow collector also operates in trailing
position.hence it requires provision of either
duplicate bows or an arrangement for
reversing the bow for runnning in reverse
direction.

8. •It is not suitable for railway work where speef
up to 120 km/h and currents up to 3000A.

9. 3.pantograph colletor
• Pantograph collector maintain link between
overhead contact wire and power circuit of the
electric locomotive at diffrent speed under all
wind conditions and stiffness of overhead
equipment.
• This necessities that positive pressure must be
maintained at all times to avoid loss of contact ad
sparking but the pressure must be as low as
possible so that wear of overhead contact wire is
minimum.

10. •It is mounted on a pentagonal framework which can
be raised or lowered by compressed air or springs.
•Compressed air for raising is normally used.