Electrical

Question 1

The two basic principles of operation for the B737 electrical system are _________ .

a. There is paralleling of the AC sources of power and the source of power being connected to a
transfer bus automatically disconnects an existing source.
b. There is no paralleling of the AC sources of power and the source of power being connected to
a transfer bus automatically disconnects an existing source.
c. There is no paralleling of the AC sources of power and the source of power being connected to
a transfer bus cannot automatically disconnect an existing source.
d. There is paralleling of the AC sources of power and the source of power being connected to a
transfer bus cannot automatically disconnect an existing source.

Answer 1

There is no paralleling of the AC sources of power and the source of power being connected to a transfer bus automatically disconnects an existing source.

Reference: FRM 6.2.1.1

Question 2

While on the ground and both generator control switches off, selecting either APU GEN switch on will _____.

a. Connect APU power to the respective transfer bus
b. Connect APU power to both transfer busses
c. Connect APU power to both transfer busses if GRD PWR is not connected
d. Connect nothing as both APU GEN switches must be placed ON within 5 seconds

Answer 2

Connect APU power to both transfer busses

Reference: FRM 6.2.3

Question 3

If the APU is running and supplying power to the busses, starting the first engine and placing its generator switch ON will _________ .

a. Powers both transfer busses
b. Allow the APU to power both transfer busses until both Engine Generators are ON
c. Automatically trips off GRD PWR
d. Powers its respective transfer bus

Answer 3

Powers its respective transfer bus

Reference: FRM 6.2.3

Question 4

If the BUS TRANSFER switch is in the AUTO position and the source powering the transfer bus is disconnected or fails, the source powering the opposite transfer bus automatically picks up the unpowered transfer bus through the BTBs.

a. True
b. False

Answer 4

True

Reference: FRM 6.2.3.1

Question 5

The amber DRIVE light is illuminated when low oil pressure is sensed in the IDG and is caused by which of the following __________ .

a. IDG Failure, Automatic disconnect due to high oil temperature
b. Engine shutdown, IDG disconnected through generator drive disconnect switch
c. Engine high RPM, High accessory case RPM
d. Both a and b

Answer 5

Both a and b

Reference: FRM 6.2.4.1

Question 6

During flight, a DC power system fault occurs. The ELEC light __________ .

a. Illuminates – follow QRH procedure
b. Illuminates - Check the TR1, 2 and 3 voltage and make a logbook write-up
c. Illuminates – make a logbook write up
d. Is inhibited in flight

Answer 6

Is inhibited in flight

Reference: FRM 6.2.5

Question 7

The cross bus tie relay automatically opens, isolating DC bus 1 from DC bus 2, under the following conditions: ____________ .

a. At glideslope capture during a flight director or autopilot ILS approach. This isolates the DC busses during approach to prevent a single failure from affecting both navigation receivers and flight control computers
b. At glideslope capture during a flight director or autopilot ILS approach. This isolates the AC
busses during approach to prevent a single failure from affecting both navigation receivers and
flight control computers
c. Bus transfer switch positioned to OFF
d. Both a and c

Answer 7

Both a and c

Reference: FRM 6.2.5.1

Question 8

What DC busses are powered from the battery (Dual battery configuration) following a loss of both generators?

a. Battery bus, DC standby bus, Hot battery bus, Switched hot battery bus
b. Battery bus, DC standby bus, Hot battery bus, DC transfer bus
c. DC standby bus, Hot battery bus, Switched hot battery bus
d. Battery bus, Hot battery bus

Answer 8

Battery bus, DC standby bus, Hot battery bus, Switched hot battery bus

Reference: FRM 6.2.5.2

Question 9

The static inverter __________ during loss of normal electrical power.

a. Converts 115V AC to 24V DC power to supply power the battery bus
b. Converts 115V AC to 24V DC power to supply the battery and battery transfer bus
c. Converts 24V DC to 115V AC power to supply the AC transfer busses
d. Converts 24V DC to 115V AC power to supply the AC standby bus

Answer 9

Converts 24V DC to 115V AC power to supply the AC standby bus

Reference: FRM 6.2.6.3

Question 10

When in flight, operating on standby power only, which Captain’s instruments are available?

a. Clock, PFD, ND, ISFD or standby Instruments, Full engine Display
b. Clock, PFD, ND, ISFD or standby instruments, Compact engine display
c. PFD, ND, ISFD or standby instruments, Compact engine display
d. PFD, ISFD or standby instruments, Full engine display

Answer 10

Clock, PFD, ND, ISFD or standby instruments, Compact engine display

Reference: FRM 6.2.6.5