Pantograph System Flashcards
What is the procedure for raising the pantograph on a previously stabled unit?
Firstly activate the auxiliary on button.
Auxiliary compressor will run until 1.5 Bar is reached.
Press the pan up/reset button for 10 secs
Watch wires to see them move and the main compressor will come in.
What’s the purpose and function of the Vacuum Circuit Breaker. VCB
VCB is located on the roof to isolate the OLE supply from getting to the transformer when passing through neutral sections and during certain fault situations.
What does the VCB require to work correctly?
Minimum air pressure of 4.5 Bar
A battery voltage of at least 65v to close and work correctly.
If your auxiliary compressor does not start what must you do to make it start?
Go to the TS MCB panel and operate the override push button which must be held for 2 minutes.
What needs to be operated if the pantograph is defective and needs to be lowered?
Operate the PANIC which is located in the roof next to the emergency cupboard panel in the TS.
What is the function of the ADD?
The automatic dropping device works by detecting if there is a problem with the pan I.e carbons damaged.
If this is detected it loses air to drop the pan down.
If the ADD occurs what indications will you receive in the cab?
The VCB light will Flash and the line light will go out.
What should you do if the ADD occurs?
Press pan down button immediately.
Stop and contact the signaller
If there is a fault with the ADD system raise pan and inspect it!
How would you isolate the ADD if it has a fault?
Operate the PADIC near emergency cupboard in the TS vehicle.
What is the overheight valve and how would you know it has operated?
The overheight valve stops the pan from raising to high if there was a gap in OLE or fault with the pan.
You will receive a flashing VCB light and the line light will go out.
You must stop and press pan down button immediately and report to the signaller.
What ensures the VCB is open when passing through a neutral section?
There are automatic power control magnets (APC) at 100ft before neutral section.
What indications will you receive in the cab when your train goes over the first APC magnet?
Line light will go out and the VCB light will be illuminated.
What will happen when you go over the APC magnet leaving the neutral section?
They will then close the VCB and the VCB light will go out and the line light will comeback on therefore regaining power.
If signaller contacts you to inform you that the APC magnet is defective when entering neutral section the. What are your actions?
You will be required to press pan up/reset button take power and gain power then shut off power before the dead section to coast through. Then press pan up/reset button again as it will then be out of sync and the exiting APC magnet
When will be the only times a driver will coast to examine the line?
- Any obstruction is not more than 6 inches below the contact wire
- The object or defect is more than 3 OLE structures away from a tunnel or overbridge.
- No more than 2 consecutive droppers have come off
- No other defect is obvious.
