The electrical system for an airliner is a very sensitive subject and a mechanic must ensure there are no possibilities for a fire occurring due to electrical wiring problems, as it can be catastrophic. The quiz below is designed to test out how much you know about wiring a Boeing 737. Give it a shot!
A fault has been detected in the AC or standby power system.
A fault has been detected in the DC or standby power system.
A fault has been detected in the DC and standby power system.
A fault has been detected in the AC and standby power system.
By the DC ground service bus 2
By the AC ground service bus 1
By the DC ground service bus 1
By the AC ground service bus 2
AC transfer bus 1 or DC bus 2 loses power
AC transfer bus 1 or DC bus 1 loses power
DC transfer bus 1 or DC bus 2 loses power
DC transfer bus 1 or DC bus 1 loses power
Yes, in flight
Only on the ground (by maintanance)
Yes on ground (by flight crew)
No
By the AC ground service bus 1
By the DC ground service bus 1
By the AC ground service bus 2
By the DC ground service bus 2
With APU running
When Ground Power is connected
Always
When the battery switch is selected to ON
That DC ground power is connected
That AC ground power is connected and meets airplane power quality standards
That Ground power can be requested
That the power is 3 phased and grounded
TRU1 or TRU2 and TRU3 have failed.
TRU1 Failed
TRU2 Failed
All TRU's Failed
Via power x-feed switch
Manually from AC transfer bus 2 via the AC tie bus.
Automatically from AC transfer bus 2 via the AC tie bus.
Automatically from the battery
Galley A
Galley B
Galley bus A + B (shed from transfer bus 1)
Galley bus A + B (shed from transfer bus 2)
115 v (+/- 5 v) and 400Hz (+/- 10 Hz)
220 v (+/- 5 v) and 400Hz (+/- 10 Hz)
115 v (+/- 5 v) and 600Hz (+/- 10 Hz)
220 v (+/- 5 v) and 600Hz (+/- 10 Hz)
24 volts DC. Range is 22 to 30 volts and supplies standby power for 30 minutes (single battery)
24 volts DC. Range is 22 to 30 volts and supplies standby power for 60 minutes (single battery)
28 volts DC. Range is 22 to 30 volts and supplies standby power for 30 minutes (single battery)
28 volts DC. Range is 22 to 30 volts and supplies standby power for 60 minutes (single battery)
28 volts DC.
24 volts DC
24 volts AC
28 volts AC
AC transfer bus 2
AC transfer bus 1
From hot battery bus
From battery bus
Trip both engine generators and APU
Connect external power and keep generators running.
Trip both engine generators and connect external power and connect external power to the transfer busses.
Ground power can not be connected with engines running.
Master FIRE WARNING lights
Master caution lights
Master FIRE WARNING lights, ENG1+ENG2 and APU fire switch lights, and WHEEL WELL FIRE light, Plus the MASTER caution lights, OVHT/DET annunciator and the ENG+ENG OVERHEAT lights.
OVHT/DET Lights
If one loop detects a fire or a overheat condition.
When both loops detect a fire condition.
When both loops detect a overhead condition
When both loops detect a fire condition or an overheat condition
With the Overheat Detector in the NORMAL position, one loop has failed
With the Overheat Detector in the NORMAL position, Both loops have failed.
With the Overheat Detector in the AUTO position, Both loops have failed.
With the Overheat Detector in the AUTO position, one loop has failed.
No, if a malfunction occurs, system is not availiable for the rest of the flight.
Yes. The defective loop is removed, and the remaining loop continues functioning as a single loop detector.
Yes, but the switch must be put in ALTN selection
Yes, but a amber OVHT light wil illuminate for the rest of the flight.
DC transfer bus 2
The hot battery bus (28v DC)
Ground power
DC transfer bus 1
Battery bus (28v DC)
Hot battery bus
Transfer bus 1
Transfer bus 2
The associated bottle discharge circuits for all 3 extinguisher bottles are normal.
That wheel extinguishers are tested and ok
The bottles are armed and have surficient contense
The three wheel well areas are tested for overheat.
It is put in AUTO mode.
Either the fire warning or overheat light illuminates.
When aircraft is in flight.
Engine ignition key is put in