Ac/dc Flashcards
When is the AC OLE live?
It should be treated live at all times!
What is the voltage of the AC overhead line equipment (OLE)?
25,000v AC
What equipment specific to OLE and 3rd rail DC on trains should be treated as live at all times?
Pantograph
Collector shoes
What is the minimum safe distance from AC OLE?
9 foot
Who would you contact to gain an AC OLE emergency switch off?
ECO
Who is in charge of the switch off?
The person who asked for it to be switched off.
If there is a rescue attempt near the OLE what is the safe distance before requesting an emergency switch off?
9 foot
Whilst driving your train you observe something hanging from the OLE that could compromise the safety of trains what must you do?
Stop the train and contact the signaller immediately as diesel trains may still be running on the line. Ensure the ECO is contacted by either you or the signaller.
What is the orange line around the top of the train called and what is its relevance?
Cant rail line. And you must not go above the line as you be to close to the OLE
When an emergency switch off is granted, the person who requested it is given a reference number. How is this number made up and what is its purpose?
It is the time so that it can be identified exactly when it happened if the person who requested the shut off needs to pass the reference number on!
What is the name of the five main wires on the OLE?
Catenary Dropper Contact Red bond Return wire
When requesting a emergency switch off for the OLE, what additional information can you give that will help identify the exact location?
Structure plate information
What is the normal voltage of the DC electrified lines?
650v - 750v
How would you ensure your safety when crossing the track in a DC electrified area?
Don’t stand on the live rail
Cross in a straight line
Ideally cross where there is a gap in the third rail
Use a bridge if possible
How can you recognise third and fourth rail areas?
Sits on insulators slightly higher
4th rail runs inside the 4ft
