Brake Component Defects Flashcards
What does the Charging Valve do?
Charges BP to 550kPa
When does Charging Valve operate?
At all times except when BCH is in EMERGENCY
When BCH in EMERGENCY it is closed to stop the BP from charging
Charging valve closes - emergency exhaust valve opens
What is the first thing to check if the BP fails to charge when you open BVICS?
Check MR to Brake Controller IC is open
If the MR to Brake Controller IC is open and BP fails to charge what do you do?
Close it - return to cab
Trip EP CB
Work BCH between RELEASE and EMERGENCY several times
Open MR to Brake Controller IC
Place BCH in RELEASE - should charge
If you are unable to charge the BP what do you do?
charge BP on a trailing MC and close BVICS once charged
Need CE. Driver operates train from leading car
With Jammed Charging Valve in leading cab and CE having charged from trailing motor, what brake is available to driver?
Only Emergency Brake available
With jammed Charging Valve in leading cab what speed can you do?
15kmh
What does the Lock Out Magnet Valve do?
When energised by 110vDC via EP CB, it locks out automatic air brake application while EP and Rheo brake is in operation
What can cause the Lock Out Magnet Valve to de-energise?
EP CB tripping
Loss of 1500vDC overhead power supply
- both of these will bring Automatic Air Brake into operation
What happens if the Lock Out Magnet Valve becomes defective in the closed (energised) position?
EXAM
No Automatic Air Brake
EP and Rheo brake operational
What happens if the Lock Out Magnet Valve becomes defective in the open (de-energised) position?
Simultaneous Automatic Air Brake, EP and Rheo brake
or
All brakes operate
If Lock Out Magnet Valve becomes defective in closed position and no Air Brake is available what does the driver have to do?
Operate train on EP and Rheo brake
Max of 15km
De-train passengers
Shunt to first available siding
If Lock Out Magnet Valve becomes defective in open position what does driver do?
Run on Air Brake
Submit TMM
What cab equipment controls the Emergency Application Valve?
Hand and Foot Pilot valve
What do you have to do if Emergency Application Valve fails to reset?
Turn Red EC Cock to isolate position
What equipment is isolated when you turn the Red EC cock?
Trip
Emergency Application Valve
Control Governor
Hand and foot pilot valve
Anti-neutralisation device
VICERS Activation valve
What makes up the Secondary Safety Equipment?
Foot pilot valve
Emergency pilot valve
Emergency Control Gov.
CG bypass push button
Once you have turned the Red EC Cock how do you operate the train?
Set foot pilot valve
Press CG Bypass button
Allow BP to recharge
- must press CG bypass button every 30 seconds
What does the Release Prevention Valve do?
Prevents the Automatic Air Brake from releasing when the BCH is in any position other than RELEASE
What brake should you use if you have a defective Release Prevention Valve?
Run on EP/Rheo
- danger is that Air brake will release when you don’t want it to
What does the Regulating Valve do?
Maintains BP pressure between:
380-410 and 550 (+/-20kPa)
How do you establish if you have a defective Regulating valve?
If BP charges to less than 550kPa …
Close BVICS …
If BP pressure falls rapidly it indicates leak in BP
If BP pressure does not fall …
BCH to EMERGENCY
Open the BVICS
Release the brake
… if BP pressure rises to its previously low level fault is in Regulating Valve
What is the minimum BP pressure you can operate a train?
425kPa
run and monitor train
Under 425kPa - train is disabled
What should you do if BCH is moving involuntarily towards RELEASE position?
Isolate the EP brake and drive using Automatic Air Brake
