ROBBDS

Question 1

When there is a power supply failure causing complete loss of traction power … what is the first step?

Answer 1

First stage:

Trips, Switches, Gauges and Cocks

Question 2

Trip?

Answer 2

Make sure Trip is lowered and set

Question 3

Switches?

Answer 3

Switches in normal positions

CBs in normal positions

Doors Closed button steady blue

Question 4

Gauges?

Answer 4

MR pressure within tolerance

BP pressure within tolerance

Control Res. pressure within tolerance

Question 5

Cocks?

Answer 5

BVICS open (if BP pressure low)

RED Emergency and Yellow TECHAV in normal position

Question 6

What CB is most likely to cause a Comeng train to fail?

Answer 6

Control CB

Question 7

If everything normal in first step … what next? (4)

Answer 7

Ensure 110 v DC supply light on

EP brake operational

LP flag lowered

Bell operates

Question 8

What does checking 110 v DC supply tell you?

Answer 8

1500 v DC overhead current is available

At least one MA is running … providing 110 v DC power

Question 9

If everything normal in first step and 110vDC power is available … what next?

Answer 9

ROBBDS Test

Question 10

What is ROBBDS Test?

Answer 10

R Reverser

O Traction Overload Reset

B BP Reduction

B CG Bypass

D Door Loop Bypass

S Second Controller

Question 11

What do you do in Reverser Test?

Answer 11

Place Reverser to REVERSE and try for power

If train powers - indicates Reverser defective in forward position … CE

If train fails to power in REVERSE move to next step

Question 12

What do you in Traction Overload Reset test?

Answer 12

Press Traction Overload Reset button
- Tests if traction overload is causing train to fail to power
- will reset any overload

Try for power again, if powers proceed and submit TMM

If doesn’t power move on to step 3

Question 13

What do you do in BP Reduction Test?

Answer 13

Reduce BP below 325 - CG opens

Restore BP above 430 - CB closes
Don’t need to know pressures
Try for power

• if train powers the fault was in CG, (Dirt between contacts) proceed and submit a TMM

If no power move on to step 4

Question 14

What do you do in the CG Bypass Test?

Answer 14

Apply and isolate brake, apply park brake

Reactive Track Access if required

Turn RED EC cock and return to cab

Cut brake back in and set FPV

Press CG Bypass to reset Emergency PV, allowing BP to recharge to 550kPa

• if train powers with emergency circuit operated fault was in CG
• if train fails to power return the EC cock to normal position and move to step 5

Question 15

What do you do in the Door Loop Bypass test?

Answer 15

Isolate the Door Loop Bypass key switch

Try for power

• if power is obtained fault is in traction inhibit system, proceed and submit a TMM - passengers must be detrained

If power is not obtained move to final step

Question 16

What do you do in the Second Master Controller test?

Answer 16

Go to another cab and see if a second master controller works.

Apply and isolate brake, ensure park brake on

PA announcement, proceed to another motor (full cab unattended)

On arrival cut in the brake, lower Trip and try for power

• If power - CE required to supply power to clear the section
• if no power, or CE not available, train is disabled