Element 5.3 - Stop trains Flashcards
1. Explain the reason why limiting the movement of the brake controller is important during braking?
To ensure a controlled smooth stop for the comfort of passengers.
Harsh braking can cause injuries.
2. What is meant by the term AWS, its purpose and how it affects the train?
Automatic Warning System
Its purpose is to tell the driver, visually and audibly, if the next signal is green (bell), or a restrictive aspect yellow or red (horn).
It also alerts the driver to a reduction in permissible speed.
If you fail to acknowledge the horn, emergency brakes will be applied.
3. What is meant by the term TPWS, its purpose and how it affects the train?
Train Protection Warning System
It does not prevent SPAD, it mitigates the the consequences of a SPAD by stopping the train before the conflict point.
TPWS wil apply emergency brakes if:
1) Train is over speeding at a reduction in permissible speed.
2) If approaching a stop signal or buffer stop too fast.
3) If you pass a signal at danger without authority.
4. What are your actions if a non-urgent GSMR communication is received during braking.
Prioritise the call based on what you are doing.
Inform signaller to wait whilst you’re completing your movement.
(if urgent put in emergency brake, and take the control of the train away from you)
5. What is meant by the term low adhesion, when is this likely to occur and what are the implications this has on train braking and driving techniques.
Low adhesion:
When friction between the wheel and rail is reduced causing the wheel to slide or spin. This can be caused by rain, leaves or oil etc on the rail.
Most likely to occur:
Autumn (leaf fall)
Winter (rain and snow)
Implications:
- Brake needs to be applied earlier as the braking distance increases.
- Sand is applied automatically when braking (brake step 2 or above) when wheel slide is detected.
- Manually apply sand when taking power to prevent wheel spin.
- Progressively take power if wheel spins.
6. What is meant by the term WSP and how does this equipment affect the train and driving performance.
Wheel Slide Protection
1) When wheel slides:
WSP applies sand (brake step 2 or above) and like ABS, rapidly releases and applies brakes many times.
Note: wheel spin is not associated with WSP
7. What is the distance a train normally stops from a signal?
20 metres
8. What is meant by the term stop car marker and where are these positioned?
Positioned on platforms, stop car markers inform the driver of the correct stopping point.
It allows the whole train to enter the platform area, and correct position for dispatch methods (mirrors, monitors etc)
