Comeng faults Flashcards
What is the effect of a Lock-out Magnet Valve being defective in the closed or energised position?
The Automatic Air Brake will only operate in Emergency
What’s does TECHAV (Primary Safety Apparatus) stand for?
• Trip
• Emergency Application Valve
• Control Governor
• Hand Pilot Valve
• Foot Pilot Valve
• Anti Neutralisation Device
• VICERS
Under what conditions should the No 1 position of the Master Controller be used mostly?
For what period must a driver press and hold the “Park Brake OFF” button?
5 sec
On a Comeng Train, the Local Park Brake Controls are located in which area?
Right hand drivers wall
If a Compressor Governor Isolating Cock has been turned to isolate, what is the effect on the train?
Compressor will run continuously
Rheostatic braking deficiencies can only be diagnosed when the train is moving above what speed?
Moving above 5 km/h
If a Control Reservoir develops a rapid air leak, why must it be isolated?
• To prevent Main Reservoir pressure from falling
• To prevent the continuous running of Air Compressors
Following reaching a terminal location, after running on the Emergency Circuit, what must a Driver do before changing ends?
• The EC cock must be turned to its
Normal position
• The TECHAV cock must be turned across the pipe
• A Fault Warning Notice must be placed in the cab
What effect would a compressor governor with contacts permanently closed have on the air compressors?
When power has been restored to
a section after a loss, Metrol may instruct drivers to raise pantographs. At what intervals will Metrol ask each driver in turn to raise pantographs?
If both headlights are non-operational during daylight hours, what Is the speed restricted to in the MURL and West Richmond tunnels?
50 km/h
True or False?
Isolation of the Rheostatic brake to determine a cause of a braking fault can only be done on a car by car basis.
True
By what method can the Rheostatic point brake be isolated on the entire train?
Because Rheostatic Brake Circuit breakers aren’t train-lined you need to turn off the circuit breakers on all motor cars.
If there is a fault in the train cable
between the first and second cars which affects the A, B and C wires from the brake controller, what will the effect be on the train?
The EP brake will not operate beyond the point of the fault
(from the second car onwards).
If the EP brake operates in Step one and two, but fails to operate in step three remaining at 70kPa in the brake cylinders, what would likely be the cause?
• A defective Lockout Magnet Valve stuck in the closed position, preventing further pressure increase.
• A failure of the B wire from the Brake Controller, which controls brake cylinder pressure beyond Step 2
If the EP or rheostatic brake is erratic in it’s performance, what 3 things must be done?
• EP circuit breaker must be tripped
• Train must be run on the Automatic Air
Brake
• TMM must be submitted
If a second BVICS is open on a train, how will this situation present itself in the leading cab?
The Flashing Blue Door Light will flash continuously
If brakes are sticking on a trailing carriage, what indication will the driver receive in the driving cab?
Wheelsleep light may or may not illuminate.
True or False?
Main Reservoir pressure will not be monitored whilst the EP Circuit breaker is tripped and Low Pressure Flag is raised.
True
When a train is running with deflated air suspension, the maximum speed is what?
50% of track speed to a maximum of 30
km/h
True or False?
Should the brake controller handle move towards a more applied position the result would be a stronger application of the brakes and therefore not detrimental to safety.
True
If a brake controller handle is moving to a more released position without
Driver input, what should be done?
• Cut out the EP circuit breaker and run on Air brake.
• Submit a TMM.
What does a steady Air Con Fault light indicate?
No more than one HVAC has failed on each trailing motor or trailer car
What does a flashing Air Con fault
light indicate?
Both HVAC units have failed on one or more trailing motor or trailer car
If a driver observes a flashing Air
Con fault light, but all HVAC units appear to be operating what else can a driver check?
Air Con Alarm Circuit breaker above No.
3 door in all cars
A wheel slip fault light illuminated whilst the train is in motion, indicates what?
A difference in speed of approximately 15 km/h between axles
A WHEELSLIP fault light illuminated whilst the train has stopped indicates what to a Driver?
That there is a fault in the wheel slip unit and its associated equipment.
The control circuit on Comeng
trains supplies current for the operation of what 6 things?
• Master Controller
• Reverser
• Traction Equipment Reset
• Remote Panto Raise
• Remote Panto Lower
• Electric Demand Circuit Breaker
If a train is failing to power and still
NOT powering after testing a second master controller, what is the next step in the fault finding procedure?
Declare train disabled
What is the correct procedure if Marker Lights and Headlights fail during darkness and it is NOT possible to reverse units to eliminate the fault?
The train must be removed from service at the first opportunity
What is the correct procedure if Marker Lights and Headlights fail during darkness and it is NOT possible to reverse units to eliminate the fault?
The train must be removed from service at the first opportunity
If normal Brake Pipe air pressure cannot be maintained, how could a driver ascertain the cause of the fault?
By closing the Brake Valve Isolating
Cock. If brake pipe air pressure remains steady the regulating valve is defective, if it falls rapidly, the brake pipe is leaking.
How many turns are required to
manually apply the Spring Park Brake fully on a Comeng tread brake train, after it has been manually released?
40 - 60
What must the Driver of a Comeng train do, if the brake pipe hose bursts between the centre motors and NO
competent employee is available?
Close the brake Pipe cocks between the centre motors, open the BVICS of the rear portion and run on EP brake. Isolate VICERS in the trailing centre motor.
If a train has failed and the trip, switches, gauges and cocks are all OK.
What must the Driver check next?
That DC and AC power are available
How many anti-clockwise turns are
required to manually release the spring park brake on a Comeng Disc Brake train?
1
If the compressors run continuously, after the Compressor Governor Circuit Breaker has been isolated, what is the Driver’s next action?
Restore the Circuit breaker to the normal position, then isolate the compressor governor circuit breaker on the next motor.
If there was a fault, somewhere on
the Rheostatic Demand Circuit of a Comeng train, which circuit breaker would trip?
Control Circuit Breaker
Consider the following scenario on a Comeng Train:
a) The Master Controller is in the closed position
b) The Reverser is in Forward, Neutral or Reverse
c) The Brake Controller is in the applied position
d) The EP Circuit Breaker in set
If the Control Circuit Breaker will not remain set, where is the probable cause of the fault? 3
• Rheostatic Brake demand wire of the Train Cable
Local Rheostatic brake controller equipment on any M Car
• Between the Control Circuit Breaker and the Master Controller
If the Automatic Air Brake becomes
inoperative on a leading motor, and no competent employee is available, what must be done?
Declare the Train Disabled
If an EP brake becomes defective, by what means would a driver isolate it?
Tripping the EP Circuit Breaker
True or False?
The rheostatic brake system will operate normally, when the EP brake is isolated.
False