Comeng Faults Flashcards
(60 cards)
1
Q
Why would you perform the ROBBDS test?
A
When the train fails to power
2
Q
What are the 2 stages of initial checks you do before starting the ROBBDS test?
A
- trips, switches, gauges, cocks
- 110vDC supply available
3
Q
What do you check for in the trips, switches, gauges and cocks stage?
A
- trip lowered and reset
- switches and mcbs in normal positions
- doors are closed (steady blue light)
- MR, BP and control governor gauges are in range
- BVICS open
- red EC and yellow TECHAV cocks in normal position
4
Q
What 3 things would you check to see if you have 110vDC available?
A
- 110 supply light is on and door close light/open light illuminated
- LP flag lowered and EP brake working
- bell operates
5
Q
What are the 6 stages of the ROBBDS test?
A
- reverser
- traction overload reset
- BP reduction
- control governor bypass
- door loop bypass
- second controller
6
Q
What are you check in step 1 (R) of the ROBBDS test?
A
- try to power with reverser in reverse
- if powers -> defective in forward position
- would need competent employee otherwise:
• disabled
• return to the rear
7
Q
What are you checking in step 2 (O) of the ROBBDS test?
A
Press traction overload reset button and try again for power
- no power -> onto next step
8
Q
What are you checking in stage 3 (B) of the ROBBDS test?
A
- BP reduction below 325kpa, recharge BP to >430kpa then try again for power (like control governor test in prep)
- fault may have been dirt caught between the contacts and this may clear it
- no power -> onto next step
9
Q
What are you checking in step 4 (B) of the ROBBDS test?
A
- control governor bypass button
- turn red EC cock, set foot pilot valve and press control governor bypass button (secondary circuit)
- if powers -> faulty control governor
- no power -> reinstate red EC cock and onto next step
10
Q
What are you checking in step 5 (D) of the ROBBDS test?
A
- door loop bypass
- isolate door loop bypass switch and try again for power -> passengers detrained
- if powers -> fault in traction inhibit system
- no power -> onto next step
11
Q
What are you checking in step 6 (S) of thr ROBBDS test?
A
- second master controller
- cut in and lower trip in another cab -> try again for power
- if powers -> C.E. required to clear section/return to rear with correct authority
- no power -> train disabled
12
Q
If you have completed the ROBBDS test and are still unable to gain traction power, what must you do?
A
Declare train disabled
13
Q
What 3 fault lights are connected to the traction system?
A
- local
- line switch
- this car
14
Q
What does the local fault light indicate?
A
Traction equipment fault has occurred (traction overload/protective device being tripped)
15
Q
What does the line switch fault light indicate?
A
- fault condition occurs on a motor car that prevents it from powering
- if line breakers are prevented from closing -> line switch remains illuminated at all times regardless of powering position
16
Q
What does the This Car fault light indicate?
A
Illuminates on the affected car where the defect is
17
Q
What are 5 things that could cause a traction fault?
A
- control reservoir faults
- pneumatic leaks
- traction overloads tripping
- 1500vDC failure
- circuit breaker failures
18
Q
What is the purpose of the control reservoir?
A
- supplies compressed air to operate equipment within the main equipment case and the line breakers case
- set the trip
19
Q
What position must the reverser be in before pressing the traction overload reset button?
A
Neutral
20
Q
What are the 4 positions of the traction cut out switch?
A
- all in (normal)
- 1 + 2 out
- 3 + 4 out
- all out
21
Q
How do you determine which motors are faulty using the traction cut out switch?
A
- isolate one bank at a time and try again for power
- if powers -> isolated bank was the faulty one
- no power -> other bank is the faulty one
22
Q
How do you find which trailing car has defective motors if it isn’t the lead motor?
A
- activate cab and set trip
- perform control governor test (from prep)
- no power -> isolate traction cut out switch
- if power -> try again in other motors until defective one is found
23
Q
If the main switch is found to be isolated and there is no TMM/traction isolated sticker, who must the driver call?
A
TC and report Main switch being isolated as per FMP
24
Q
Can a driver reinstate the main switch if it has been isolated?
A
No
25
What 5 things run off 1500vDC?
- pantos
- MAs
- compressors
- traction equipment
- associated circuits
26
How many times will the overhead system attempt to reset itself when there is a loss of overhead?
2
27
What is the purpose of the Loss of Overhead Shutdown Module (LSM switch)?
- detects a loss of voltage in 100vDC supply and shut-down systems on the train
- done to protect substation from overloading when power is returned
28
What will metrol request drivers to do if there is a loss of overhead power?
Lower all pantos
29
If power can be restored, what will metrol request the drivers to do?
Raise all pantos, one train at a time
30
Ar what intervals will metrol request trains to depart after overhead is restored?
1 minute
31
What notch must a driver depart in once advised to depart?
Series
32
If overhead is restored, but there are no communications, at what intervals must trains depart on the:
- up
- down
- up -> 30 seconds
- down -> 60 seconds
33
For how long will emergency lighting and the PA system last for after a loss of overhead?
2 hours
34
What light will flash to indicate the emergency lighting needs to be reset?
Battery charger
35
Which switch must be turned to reset the emergency lighting?
Marker lights -> go to another position then back to auto
36
What position must the LSM switch always be in?
On
37
What are the 2 components of the LSM?
- time delay relay
- speed threshold
38
What time limit is the time delay relay set to?
4 minutes
39
What is the speed threshold of the LSM module?
8km/h
40
What voltage must the 110vDC output drop to and for how long for LSM to take effect?
95vDC for 2 continuous seconds
41
What will happen to the pantographs and the motor alternators when:
- speed <8km/h within 4 mins (BVICS open/closed)
- speed 0km/h with timer exceeding 4mins
- speed >8km/h
- speed <8km/h:
• lead panto raised -> all others lowered
• local MA contactors closed -> all others opened
- speed 0km/h:
• all pantos lower
• all MA contactors open
- speed >8km/h:
• nothing until speed <8km/h
42
How long does the VICERS battery back up last?
5 mins
43
What will happen if the timer on the VICERS battery back up runs out?
- VICERS activation valve opens -> BP vents to atmosphere
- put brake handle into emergency to maintain MR pressure
44
How will metrol locate the train causing the overhead power to be lost?
- ask all trains one at a time to raise all pantos and start MAs
- when overhead power is lost -> that's the defective train
45
How will a driver be able to determine which motor car is causing the overhead power to be lost?
- raise each panto individually
- start each MA locally
- when overhead power is lost -> that's the defective motor car
46
How will a driver isolate the defective equipmemt once the motor car has been found?
- lower local panto using EP valve
- isolate panto electrically and pneumatically
- motor cut out switch to all out
47
What button can a driver press to try to reset a traction overload?
Traction equipment reset button
48
What does a local fault light indicate?
An overload has tripped on a motor car
49
What does a line switch fault light indicate?
Line breaker has failed to close on a motor car
50
What does a motor alternator fault light indicate?
An MA is not running or is not providing electrical output on a motor car
51
What does a rheostatic brake fault light indicate?
A rheo brake has failed to set up correctly on a motor car
52
What does an air conditioner fault light indicate?
- steady -> no more then one air con failed on any one car
- flashing -> both air con failed on one or more cars
53
What does a wheel slip indicator fault light indicate?
- stationary -> fault in wheel slip unit and its associated equipment
- in motion -> indicates difference of >15km/h between axles while powering or braking caused by slippery conditions or defective wheel slip unit
54
What does a park brake fault light indicate?
One or more SPB applied on the train
55
What does a foot pilot valve indicator light indicate?
If the foot pilot valve is set
56
What does the this car fault light indicate?
Location of a fault in conjunction with other fault lights being illuminated
57
What 6 pieces of equipment makes up the control circuit? (MRBOPC)
- master controller
- reverser
- brake demand (rheo)
- overload reset button
- panto raise/lower buttons
- control governor (speedo)
58
What happens if the controp mcb trips in the lead motor?
- train will fail
- master controller inoperative and no train lined signals can be sent to the traction equipment
59
What will a driver have to do if the control mcb trips when pressing remote PANTO RAISE button?
- fault between master controller and mcb if mcb can't be reset
- raise pantos manually at each motor car
- TMM
- prevention -> don't use panto raise button to remotely raise pantos
60
What will a driver have to do if the control mcb trips when pressing remote PANTO LOWER button?
- fault between master controller and mcb if mcb can't be reset
- reset mcb
- electrically isolate panto EP valve with switch
- press remote panto lower again
- if remains set -> fault in EP valve, manually lower and isolate panto and TMM
- if trips again -> repeat above procedure on each motor car until defective EP valve is located
- can't enter service if pantos can't be remotely lowered from lead cab
