B737 System Validation Question Bank -Electrical R3

Front 1

737NG Electrical Diagram

Back 1

737NG Electrical Diagram

Front 2

737-500 Electrical Diagram

Back 2

737-500 Electrical Diagram

Front 3

1. How is the electrical system managed when a fault occurs?
a. The electrical system monitors itself for faults and automatically disconnects a Generator bus from its power source when electrical power is out of limits
b. The crew must monitor electrical meters for faults and manually disconnect a Generator bus from its power source when electrical power is out of limits
c. The electrical system monitors itself for faults only on the ground, the crew must monitor electrical meters for faults while in flight.

Back 3

a. The electrical system monitors itself for faults and automatically disconnects a Generator bus from its power source when electrical power is out of limits

Front 4

2. What is the normal source of power for an AC TRANSFER bus?
a. Opposite GEN bus
b. Respective MAIN bus
c. Respective GEN bus

Back 4

c. Respective GEN bus

Front 5

3. CONDITIONS: Both engine driven generators on line; APU shut down; BUS TRANSFER switch in the AUTO position. Which buses are not powered if #2 engine driven generator trips off?
a. All AC and DC buses on both sides
b. Generator bus, Main bus, and Transfer buses on failed side
c. Generator bus and Main bus on failed side

Back 5

c. Generator bus and Main bus on failed side

Front 6

4. What is the power source for TR-3?
a. AC Generator Bus #1
b. Main Bus #2
c. Main Bus #1

Back 6

b. Main Bus #2

Front 7

5. What is the normal source of power for TRs 1 and 2?
a. Respective AC TRANSFER buses
b. Respective GEN buses
c. Respective MAIN AC buses

Back 7

a. Respective AC TRANSFER buses

Front 8

7. How does the TR 3 disconnect relay normally function?
a. Automatically closes when the crew conducts a raw data approach
b. Automatically closes when TR 1 fails to allow TR 2 to power the DC bus One
c. Automatically opens during an A/P or FD approach at glide slope capture

Back 8

c. Automatically opens during an A/P or FD approach at glide slope capture

Front 9

8. What is the power source for the Hot Battery bus when all aircraft buses are powered?
a. Battery charger
b. Aircraft Batter
c. TR 3

Back 9

a. Battery charger

Front 10

9. What is the normal source of power for the AC Ground Service bus?
a. #1 Generator Bus
b. #2 Generator Bus
c. #2 Main Bus

Back 10

a. #1 Generator Bus

Front 11

10. What is the normal source of power for the Battery bus?
a. TR 1
b. TR 2
c. TR 3

Back 11

c. TR 3

Front 12

11. What is the normal source of power for the Battery Charger?
a. AC GROUND SERVICE bus
b. #1 MAIN bus
c. #2 MAIN bus

Back 12

a. AC GROUND SERVICE bus

Front 13

12. The aircraft is in flight with only the battery for electric power. Where does the power come from for the AC and DC Standby buses?
a. #2 Main bus for the AC Standby bus, and #2 DC bus for the DC Standby bus
b. Static Inverter for the AC Standby bus, and Battery bus for the DC Standby bus
c. Battery charger through the Hot Battery bus for both Standby buses

Back 13

b. Static Inverter for the AC Standby bus, and Battery bus for the DC Standby bus

Front 14

13. What is the alternate power source for the Battery bus?
a. TR 1
b. TR 2
c. Hot Battery bus

Back 14

c. Hot Battery bus

Front 15

14. What is the alternate source of power for the Hot Battery bus when the normal power source is not available?
a. Battery
b. Battery charger
c. External power

Back 15

a. Battery

Front 16

15. What is the alternate power source for the Battery Charger
a. Generator Bus 1
b. Ground Service Bus
c. Main Bus 2

Back 16

c. Main Bus 2

Front 17

16. What is the purpose of the CSD?
a. Change constant engine speed into variable generator speed
b. Change variable engine speed into constant generator drive speed
c. Automatically disconnects generator drive with a feeder fault trip

Back 17

b. Change variable engine speed into constant generator drive speed

Front 18

18. Which of the following must be accomplished to check the battery condition?
a. Turn on the battery switch, place DC meter selector to BAT, check volts within limits
b. Turn on the batter switch, place DC meter selector to BAT BUS, check volts and amps within limits
c. Turn on the batter switch, place DC meter selector to BAT, check volts and frequency within limits

Back 18

a. Turn on the battery switch, place DC meter selector to BAT, check volts within limits

Front 19

19. How is a failure of TR 1 indicated with the TR 3 disconnect relay closed?
a. 0 amps, 0 volts indicated on the DC meters at the TR 1 position
b. 0 volts, normal amps indicated on the DC meters at the TR 1 position
c. 0 amps, normal volts indicated on the DC meters at the TR 1 position

Back 19

c. 0 amps, normal volts indicated on the DC meters at the TR 1 position

Front 20

20. How would a failure of the static inverter be indicated during the standby power check?
a. 0 volts on the AC volt meter and 0 amps on the AC frequency meter
b. 0 amps indicated on the DC ammeter
c. 0 volts indicated on DC volt meter

Back 20

a. 0 volts on the AC volt meter and 0 amps on the AC frequency meter

Front 21

21. What is the function of the ON position of the gallery power switch?
a. Powers respective gallery from its associated Transfer bus
b. Powers all galleys when either Generator bus is powered
c. Powers all galleys when both Generator buses are powered

Back 21

c. Powers all galleys when both Generator buses are powered

Front 22

22. With the battery switch ON, which statement is correct?
a. This switch is the only means available for turning on the battery bus
b. Both the Battery bus and Switched Hot Battery bus are powered
c. Provides the only means to power Standby buses from the Battery

Back 22

b. Both the Battery bus and Switched Hot Battery bus are powered

Front 23

23. Which statement describes establishing power to the Ground Service Bus on the ground?
a. GRD POWER AVAILABLE light on, GROUND SERVICE switch on
b. APU GEN OFF BUS light on, GRD PWR switch ON
c. GEN OFF BUS lights on, GRD service switch ON

Back 23

a. GRD POWER AVAILABLE light on, GROUND SERVICE switch on

Front 24

24. What does an illuminated STANDBY PWR OFF light indicate?
a. The DC Standby bus is unpowered
b. The AC Standby bus is unpowered
c. The AC and DC Standby bus is unpowered

Back 24

b. The AC Standby bus is unpowered

Front 25

25. What is the function of the AUTO position of the STANDBY POWER switch with loss of all AC power?
a. Allows the Battery Charger to be source of power for both Standby buses inflight or on the ground
b. Allows the BATTERY BUS to be the source of power for both Standby buses inflight
c. Allows the SWITCHED HOT BATTERY bus to be the source of power for both Standby buses inflight

Back 25

b. Allows the BATTERY BUS to be the source of power for both Standby buses inflight

Front 26

26. What does an illuminated CSD HIGH OIL TEMP light indicate?
a. CSD oil temperature exceeds operating limits
b. CSD “IN” oil temperature is in the yellow caution range
c. CSD “RISE” oil temperature is in yellow caution range

Back 26

a. CSD oil temperature exceeds operating limits

Front 27

27. Which is correct for disconnecting a CSD?
a. Hold generator drive disconnect switch to DISCONNECT for 3-seconds. The CSD may be reengaged inflight at idle engine speed
b. Momentarily place generator drive disconnect switch to DISCONNECT. The CSD may be re-engaged by placing the switch guard down.
c. Hold generator drive disconnect switch to DISCONNECT momentarily. The CSD may re-engaged on the ground by maintenance

Back 27

c. Hold generator drive disconnect switch to DISCONNECT momentarily. The CSD may re-engaged on the ground by maintenance

Front 28

28. What does an illuminated GRD POWER AVAILABLE light indicate?
a. Ground cart is plugged in and powering the aircraft buses
b. Ground cart is plugged in and output is within limits
c. Ground cart is plugged in and external bus is powered

Back 28

c. Ground cart is plugged in and external bus is powered

Front 29

29. What is the function of the ON position of the GRD PWR switch?
a. Connects ground power directly to both Transfer buses if ground power is within voltage and frequency limits
b. Connects ground power to both Generator buses if the ground power quality is correct
c. Connects ground power directly to both Transfer buses regardless of ground power voltage and frequency limits

Back 29

b. Connects ground power to both Generator buses if the ground power quality is correct

Front 30

30. What is the function of the OFF position of the BUS TRANSFER switch?
a. Prevents operation of bus transfer relays, sheds window heat & electric hydraulic pumps, prevents charger from switching to Main Bus 2, and opens TR-3 disconnect relay
b. Disconnects both Transfer Buses from their respective Generator Buses, prevents battery charger switching to alternate power, and opens TR-3 disconnect relay
c. Prevents operation of bus transfer relays prevents battery charge from switching to Main Bus 2, and opens TR 3 disconnect relay

Back 30

c. Prevents operation of bus transfer relays prevents battery charge from switching to Main Bus 2, and opens TR 3 disconnect relay

Front 31

31. What does an illuminated BUS OFF amber light indicate?
a. The APU generator is supplying the respective bus
b. The respective Generator bus is unpowered
c. The engine or APU generator is supplying the Generator bus

Back 31

b. The respective Generator bus is unpowered

Front 32

32. What does an illuminated TRANSFER BUS OFF light indicate?
a. Respective Transfer bus is unpowered
b. Engine generator is not supplying respective Transfer bus
c. Transfer bus switch is in the OFF position

Back 32

a. Respective Transfer bus is unpowered

Front 33

33. What is the function of the APU Generator switches?
a. Connects generator output to Generator bus regardless of power quality
b. Connects generator output to Generator bus if power quality is correct
c. Connects generator output to Main bus if power quality is correct

Back 33

b. Connects generator output to Generator bus if power quality is correct

Front 34

34. In flight, the AC Ground Service bus is powered by:
a. Generator Bus 1
b. Main Bus 1
c. Main Bus 2
d. Generator Bus 2

Back 34

a. Generator Bus 1

Front 35

35. Engine driven generator maximum load is:
a. 125 Amps
b. 150 Amps
c. 125 Amps ground, 150 amps flight
d. 150 amps ground, 125 amps flight

Back 35

a. 125 Amps

Front 36

36. In the air, galley power is available only when both generator buses are powered.
a. True
b. False

Back 36

a. True

Front 37

37. All power sources to a GEN BUS must be manually connected through the movement of a switch.
a. True
b. False

Back 37

a. True

Front 38

38. What are the Transformer Rectifier operating parameters?
a. 18-20 volts
b. 24-30 volts
c. 50-65 volts

Back 38

b. 24-30 volts

Front 39

39. With a loss of all generators, a fully charged battery can supply power to the standby buses for at least
a. 20 minutes
b. 30 minutes
c. 45 minutes
d. 60 minutes

Back 39

b. 30 minutes

Front 40

40. On the ground, alternate power for the Standby buses requires:
a. Standby power switch at BAT
b. Bus transfer switch at OFF
c. Bus transfer switch at AUTO
d. Standby power switch at AUTO

Back 40

a. Standby power switch at BAT

Front 41

41. With loss of normal AC power in flight, power for the Standby AC and Standby DC buses is automatically available from:
a. Main bus 2 and TR 3
b. Transfer bus 2 and DC bus 2
c. Battery bus and Static inverter
d. None of the answers are correct

Back 41

c. Battery bus and Static inverter

Front 42

42. A ground service bus control switch, labeled “GROUND SERVICE” is located on the :
a. Forward overhead panel
b. External power receptacle panel
c. Aft flight attendant panel
d. Forward flight attendant panel

Back 42

d. Forward flight attendant panel

Front 43

43. An amber “BUS OFF” light is:
a. Illuminated when TR 3 fails
b. Illuminated when the corresponding GEN bus is powered
c. Extinguished when the corresponding GEN bus is powered

Back 43

c. Extinguished when the corresponding GEN bus is powered

Front 44

44. What is the maximum engine generator electrical load limit?
a. 100 amps
b. 125 amps
c. 150 amps

Back 44

b. 125 amps

Front 45

45. What is the minimum battery voltage for an APU start?
a. 22 volts
b. 23 volts
c. 24 volts
d. 25 volts

Back 45

b. 23 volts

Front 46

46. When a CSD LOW OIL PRESSURE or HIGH OIL TEMP light comes on, the system annunciator and Master Caution lights illuminate.
a. ELEC
b. GEN
c. ENG
d. HYD

Back 46

a. ELEC

Front 47

47. The light is illuminated when the External AC Bus is powered.
a. GRD POWER AVAILABLE
b. BUS OFF
c. TRANSFER BUS OFF
d. GEN OFF BUS

Back 47

a. GRD POWER AVAILABLE

Front 48

48. What is the basic AC power distributor? (300/500)

Back 48

a. AC power source to the GEN BUS, GEN BUS supplies its respective MAIN AC BUS and TRANSFER AC BUS

Front 49

49. The DRIVE light for an IDG illuminates when (700/800/900)

Back 49

a. All answers are correct

Front 50

50. What is the maximum single engine drive generator load for an 800 model aircraft on the ground?

Back 50

a. 215 amps

Front 51

51. When a B737-700 model IDG is operating and the IDG breaker is closed, the IDG output is connected to:

Back 51

a. An AC TRANSFER BUS

Front 52

17. Which DC Selector positions display DC amps?
a. TRs 1,2,3, and BAT
b. BAT BUS, and STBY PWR
c. All selectable positions

Back 52

a. TRs 1,2,3, and BAT

Front 53

6. What is the “backup” source of power for DC Bus 1?
a. #2 DC Bus
b. #2 TR
c. DC Standby bus and Battery

Back 53

b. #2 TR