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BOEING 747-400 - Electrical

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BOEING 747-400 - Electrical Empty BOEING 747-400 - Electrical

Post  Admin Wed Dec 02, 2009 3:02 am

Q 1. What produces DC power on this airplane?

A. DC IDGs.
B. Transformer-rectifier units (TRUs)
C. Standby Inverters

Q 2. When is the EICAS advisory message ELEC DRIVE 1, 2, 3, 4 is displayed?

A. An IDG has high oil temperature or low oil pressure.
B. An IDG has been manually disconnected.
C. The generator control breaker (GCB) is open with its respective engine running.
D. The respective bus tie breaker (BTB) is open.

Q 3. When does the EICAS advisory message ELEC UTIL BUS L, R display and the respective Utility OFF light illuminate?

A. When load shedding occurs.
B. If one or more utility or galley busses become unpowered due to a fault.
C. When all Utility Power Switches are OFF.

Q 4. If one or more utility busses become unpowered due to a fault or when the respective Utility Power Switch is OFF.
When is the EICAS advisory message DRIVE DISC 1, 2, 3, 4 is displayed?

A. An IDG has low oil pressure or high oil temperature.
B. The respective engine is shut down.
C. An IDG has been manually disconnected.
D. An IDG has been either manually or automatically disconnected.

Q 5. (Freighter) What is the normal power source for the Main Standby Bus?

A. From AC Bus 3.
B. From AC Bus 2.
C. From AC Bus 1.
D. From the Main standby inverter.

Q 6. Each IDG can be mechanically disconnected from its engine accessory gearbox:

A. By pushing the Generator Drive Disconnect switch and can be restored by a second push on the switch.
B. By pushing the Generator Drive Disconnect switch and cannot be restored by flight crew action.
C. By pushing the Generator Control switch to OFF.

Q 7. (Passenger) What is the normal power source for the Standby Bus?

A. From AC Bus 3.
B. From AC Bus 2.
C. From AC Bus 1.
D. From the standby inverter.

Q 8. Pushing the External Power (EXT PWR) 2 Control Switch when ON light is illuminated:

A. Disconnects related external power from AC electrical system.
B. Connects related external power to AC electrical system.
C. Connects related external power to the Ground Handling Bus.

Q 9. Where are the battery voltage, current, and charge indications are displayed?

A. On the electrical synoptic.
B. Nowhere on the flight deck.
C. On the status display.
D. On the status display or the electrical synoptic.

Q 10. When does the Generator Control Breaker (GCB) automatically close?

A. When the APU generator is providing power to the synchronous bus.
B. When the respective Generator Control switch is ON and the generator power quality is acceptable.
C. When the respective Generator Control switch is ON.
D. When the external power is plugged in.

Q 11. When engine # 1 is started with a single external power source powering the electrical system:

A. IDG powers the entire synchronous bus when voltage and frequency are acceptable.
B. The IDG powers its side of the synchronous bus when voltage and frequency are acceptable.
C. External power remains connected to the electrical system.

Q 12. The AC Bus Isolation Lights for AC Busses 1,2, and 3 will illuminate during a triple channel autoland.

A. True
B. False.

Q 13. The respective Generator Control Switch must be ON and the IDG power quality acceptable for the IDG to provide AC power to its respective AC Bus.

A. True
B. False.

Q 14. What actions happen when the Bus Tie Switch is placed in the AUTO position?

A. The respective DC isolation relay arms.
B. The bus tie breaker (BTB) is closes.
C. Automatic operation of the generator control breaker (GCB) is enabled.
D. The respective DC isolation relay closes and automatic operation of the bus tie breaker (BTB) is armed.

Q 15. With the airplane on the ground, AC power can be paralleled on the synchronous bus from two external power sources and/or both APU generators.

A. True
B. False.

Q 16. With both APU generators connected and the number 4 engine started, the respective IDG automatically powers its side of the synchronous bus and the previous power source is disconnected.

A. True.
B. False.

Q 17. Which electrical source normally powers the Captain’s transfer bus?

A. AC bus 3.
B. AC bus 2.
C. AC bus 1.
D. APU Standby Bus.

Q 18. Flight critical equipment on the standby bus receives AC power from the standby inverter when AC bus 3 is unpowered and the Standby Power Selector is in the AUTO position.

A. True
B. False.

Q 19. (Passenger) With the Battery Switch ON and Standby Power Selector in BAT, which of the following best describes the operation of the DC electrical system?

A. The main battery charger powers the standby bus through the main hot battery bus and standby inverter.
B. The APU battery powers the APU standby bus through the APU hot battery bus and APU standby inverter.
C. Both battery chargers are disabled.
D. The APU battery powers the APU hot battery bus and APU battery bus. Both battery chargers are disabled and each battery can provide power for a minimum of 30 minutes. The main battery powers the standby bus through the main hot battery bus and standby inverter.

Q 20. APU generator 1 will power the ground handling bus if both external power and APU power are available.

A. True
B. False.

Q 21. What powers the ground handling bus during preflight if both external power and APU power are available?

A. If both APU and External power are available, external power 2 is used.
B. If both APU generator 1 and External power 1 are available, APU power is automatically used.
C. If both APU generator 1 and External power 1 are available, External power is automatically used.
D. If both APU and External power are available, APU generator 2 is used.

Q 22. Which of the following best describes system(s) which receive power from the ground handling bus?

A. The fueling system.
B. Cargo handling equipment, cargo compartment lights and hydraulic pump 4.
C. The main and APU battery chargers.

Q 23. Lower cargo handling equipment, cargo compartment lights, auxiliary hydraulic pump 4 and the fueling system.
After landing, how does transfer of power from IDG to APU or external power occur?

A. Automatically when APU is started or external power is connected.
B. Manually.
C. Automatically during engine shutdown.

Q 24. The white External Power Available (AVAIL) Lights indicate that:

A. Related external power is connected to the AC electrical system.
B. External power is disconnected from the airplane.
C. Related external power source is plugged in, power quality acceptable.

Q 25. With the Standby Power Selector in AUTO and the standby bus powered from the standby inverter (assume Battery Switch ON), what EICAS message should be displayed and what are the associated limitations?

A. The EICAS message ELEC AC BUS 3 is displayed and there is no time limit
B. The EICAS message ELEC AC BUS 3 is displayed and there is a 30 minute time limit
C. The EICAS messages ELEC AC BUS 1 and BAT DISCH MAIN are displayed and there is a 30 minute time limit
D. No EICAS message are displayed

Q 26. What occurs if available power is less than the demand?

A. The electrical load control units (ELCU) shed galley and galley and utility busses according to priority logic
B. No EICAS messages are diplayed during load shedding
C. The Utility Off Lights do not illuminate
D. All of the above.

Q 27. When is the EICAS advisory message ELEC UTIL BUS displayed?

A. A fault has occurred on the utility or galley bus and the bus is unpowered
B. The Utility Power Switch is OFF
C. The Utility Power Switch is ON with galley bus unpowered.
D. The Utility Power Switch is OFF & a fault has occurred on the utility or galley bus and the bus is unpowered

Q 28. How are the four main DC busses interconnected?

A. Through the AC bus 3 and TRU 3 to power the APU hot battery bus if there is a failure in the Captain\\\'s transfer bus.
B. Through relays in the Synchronous Bus.
C. Through the DC isolation relays and the DC tie bus if there is an AC bus or TRU failure.
D. Through each IDG connected to the synchronous bus by each BTB.

Q 29. Pushing a Bus Tie Switch OFF opens the associated DC isolation relay and the respective DC bus is powered by its respective AC bus and TR unit.

A. True.
B. False.

Q 30. The main hot battery bus and the APU hot battery bus are always connected to their respective batteries.

A. True
B. False.

Q 31. The EICAS advisory message BATTERY OFF is displayed when the main battery is discharging.

A. True.
B. False.

Q 32. When is the EICAS advisory message BAT DISCH APU displayed?

A. The Battery Switch is OFF.
B. The APU battery bus has a fault.
C. The APU battery is discharging.
D. The APU has automatically shut down due to a battery fault.

Q 33. What happens when the Battery Switch is pushed ON and no other power sources are connected?

A. The main and APU batteries are connected to their respective battery busses
B. All indicator and flight deck switches necessary for APU start are activated
C. Fire protection systems will not be available until external or APU generator power is available

Q 34. Selecting AUTO on the Standby Power Selector, with the Battery Switch ON, activates the PRIMARY EICAS display which will display required caution and warning

A. True.
B. False.

Q 35. What occurs when the Utility Power Switches are positioned ON?

A. The electrical load control units are enabled
B. The utility and galley busses are connected immediately

Q 36. The AC Bus Isolation lights and EICAS advisory message ELEC BUS ISLN will be displayed during autoland.

A. True
B. False

Q 37. Which AC bus serves as the backup power source for the Captain’s and First Officer’s transfer busses?

A. AC Bus 2
B. AC Bus 3
C. AC Bus 1
D. AC Bus 4

Q 38. Which of the following statements is true when the left Utility Bus Switch has been pushed ON?

A. The Utility busses are normally powered by AC bus 2 and the galley busses are normally powered by AC bus 3. AC bus 1 serves as a backup source of power.
B. Utility bus 1 and galley bus 1 are powered by AC bus 1, utility bus 2 and galley bus 2 are powered from AC bus 2.
C. Utility bus 1 and utility bus 2 are powered by AC bus 1; galley bus 1 and galley bus 2 are powered by AC bus 2.

Q 39. What conditions cause the EICAS advisory message ELEC UTIL BUS to be displayed?

A. When either the Utility Power Switch is pushed OFF or when the switch is ON and power has be automatically removed from one or more of the respective utility and galley buses because a fault has been detected.
B. When either the Utility Power Switch is pushed OFF or when the switch is pushed ON, and one or more utility or galley busses has loadshed.
C. When Utility Power Switch is pushed OFF.

Q 40. Which statement accurately describes the standby bus?

A. Certain flight critical equipment receives AC power through the stanby bus
B. The standby bus provides backup DC power to the battery busses
C. The standby bus is normally powered by the main battery bus through a standby inverter

Q 41. Which of the following conditions are correct during autoland?

A. AC and DC busses 1,2, and 3 are automatically isolated.
B. AC Bus 1, 2 and 3 Isolation lights and associated ELEC BUS ISLN - EICAS messages will be displayed.
C. AC bus 3 continues to power the synchronous bus.
D. These isolated busses can be visually verified by displaying the electrical synoptic.

Q 42. When autoland is engaged, system logic provides independent power sources for each of the three autopilots. Which of the following statement is correct?

A. Electrical system configuration is displayed on the electrical synoptic.
B. When autoland is engaged, AC busses 1, 2 and 3 are automatically isolated. The DC isolation relays 1, 2 and 3 remain closed. C. AC bus 4 continues to power the synchronous bus.
D. When autoland is engaged, the split system breaker opens, providing two independent sources of power for autopilots A and B. The standby bus powers autopilot C.
E. When autoland is engaged, AC and DC busses 1, 2 and 3 are automatically isolated. AC bus 4 continues to power the synchronous bus.

Q 43. If main AC busses 2 and 3 fail, the Captain\\\'s and First Officer\\\'s Transfer Busses are powered by:

A. AC Bus #1
B. AC Bus #2
C. AC Bus #3
D. AC Bus #4

Q 44. Pulling an Engine Fire Handle:

A. Trips off the related IDG.
B. Mechanically disconnects related IDG from its engine accessory gear box.
C. Isolates associated AC bus from the synchronous bus

Q 45. What does the EICAS message ELEC GEN OFF 3 mean?

A. Number 3 generator no longer provides power to its respective AC bus
B. The generator control breaker is open when the engine is running
C. The synchronous bus powers AC bus 3
D. All of the above.

Q 46. When accomplishing the ELEC GEN OFF non-normal procedure, which of the following is a correct QRH procedure action?

A. Attempt only one reset of the Generator Control Breaker.
B. Do not accomplish the DRIVE DISC checklist.
C. The SSB should be commanded closed.
D. Reset the circuit breaker.

Q 47. During an approach using autoland, the number 2 IDG fails. AC bus 4 still powers the synchronous bus and AC bus 2. The EICAS advisory message ELEC BUS ISLN 2 is displayed.

A. True
B. False

Q 48. What occurs to cause the display of the EICAS advisory message ELEC BUS ISLN 1, 2, 3, 4?

A. The respective BTB is open and associated AC Bus Isolation light is illuminated.
B. The respective AC bus is not automatically isolated from the synchronous bus and has to be manually disconnected.
C. \\\"ELEC BUS ISLN\\\" is displayed on the electrical synoptic.
D. If the message is displayed during Autoland, LAND 3 is not available.

Q 49. With the airplane on the ground and the engines shutdown, how is each side of the synchronous bus powered?

A. The APU powers both sides of the synchronous bus with the (SSB) closed.
B. If two sources of auxiliary power source are selected, the Split System Breaker (SSB) closes.
C. If only one power source (single external power or single APU generator) is selected the Split System Breaker (SSB) will close and both sides of the synchronous bus will be powered.
D. If one auxiliary power source is disconnected or fails, the SSB opens.

Q 50. With both APU generators powering the synchronous bus and the start sequence is 4, 3, 2, 1, what happens after the number 4 engine is started?

A. APU generator 1 is automatically disconnected.
B. The number 4 IDG automatically powers both sides of the synchronous bus.
C. The Split System Breaker remains closed.
D. APU generator 2 is automatically disconnected. The number 4 IDG automatically powers it\\\'s side of the synchronous bus. E.The Split System Breaker remains open.

Q 51. With the Standby Power Selector in AUTO and AC bus 3 unpowered (Battery Switch ON), what EICAS message should be displayed and what are the associated limitations?

A. The EICAS message ELEC AC BUS 3 is displayed and there is no time limit on standby power.
B. The EICAS message ELEC AC BUS 3 is displayed and there is a 30 minute time limit on the standby power.
C. The EICAS message ELEC AC BUS 1 and BAT DISCH MAIN are displayed and there is a 30 minute time limit on standby power.
D. No EICAS messages are displayed.

Q 52. What occurs if available generator power is less than electrical system demand?

A. Loads are shed one at a time through electrical load control units (ELCUs) in a programmed sequence, the Utility OFF system lights illuminate and the EICAS ELEC UTIL BUS messages are displayed.
B. Loads are shed one at a time through electrical load control units (ELCUs) in a programmed sequence but the Utility OFF system lights do not illuminate and the EICAS ELEC UTIL BUS messages are displayed.
C. Loads are shed one at a time through electrical load control units (ELCUs) in a programmed sequence but the Utility OFF system lights illuminate and the EICAS ELEC UTIL BUS messages are not displayed.
D. Loads are shed one at a time through electrical load control units (ELCUs) in a programmed sequence but the Utility OFF system lights do not illuminate and the EICAS ELEC UTIL BUS messages are not displayed.

Q 53. Which electrical bus powers the Captain’s interphone, left radio tuning panel, and left VHF?

A. The APU hot battery bus.
B. The main battery bus.
C. The main standby bus.
D. The Captain’s transfer bus.

Q 54. What happens when a Bus Tie Switch is Pushed OFF?

A. The respective DC isolation relay opens and the associated DC bus remains powered by its respective AC bus via a TRU.
B. The respective DC isolation relay opens and the associated AC bus remains powered by its TRU.
C. The respective DC isolation relay closes and the associated DC bus is not powered.
D. The respective DC isolation relay closes and the associated DC bus remains powered by its associated AC bus and TRU.

Q 55. How are the main hot battery bus and the APU hot battery bus normally powered?

A. By DC bus 2.
B. By the Ground Service bus through it\\\'s related battery charger.
D. With the Battery Switch ON, each battery bus is connected to it\\\'s related hot battery bus by the related BTB.
E. By the Ground Handling bus through it\\\'s related battery charger.

Q 56. The Main Hot Battery Bus powers individual equipment items. Which of the following is the most complete list of this equipment?

A. APU fuel shutoff valve, spar valves (all engines).
B. APU and lower cargo fire extinguishers.
C. Engine fire extinguishers, fire switch unlock (all engines).
E. APU fuel shutoff valve, spar valves (all engines), APU and lower cargo fire extinguishers, and engine fire extinguishers (all engines), and fire switch unlock (all engines).

Q 57. Which of the following best describes what systems are available when battery power is the only electrical power available on the ground?

A. Engine fire extinguishers (all engines) but the Fire Switches can not be manually unlocked.
B. IRU left, center and right receive DC power as long as battery power is available.
C. Only a single APU and engine fire/overheat detection loop is powered.
D. The APU controllers, The Captain\'s and First Office\'s interphone, all engine fuel valves, engine start air control, all engine spar valves and the APU fire warning horn are powered.

Q 58. (Freighter) Which of the following best describes what happens during the preflight with the Battery Switch ON and then selecting AUTO on the Standby Power Selector?

A. The main standby bus becomes powered and the primary EICAS display on the upper CRT activates, the APU standby bus powers the left FMC, left PFD and left ND and standby ignition for all engines is powered.
B. The APU standby bus powers the FMC, PFD and the ND.
C. Standby ignition for all engines is powered.
D. The main standby bus becomes powered and the primary and secondary EICAS display on the upper CRT activates.

Q 59. (Freighter) With the Battery Switch ON, Standby Power Selector in AUTO, and AC Bus 3 not powered, how does flight critical equipment on the Main Standby Bus automatically receive AC power?

A. APU standby inverter.
B. Main standby inverter.
C. APU battery bus.
D. TRU #3.

Q 60. (Freighter) With the Battery Switch ON and Standby Power Selector in BAT, which of the following best describes the operation of the DC electrical system?

A. The main battery powers the main standby bus through the main hot battery bus and main standby inverter.
B. The APU battery powers the APU standby bus through the APU hot battery bus and APU standby inverter.
C. Both battery chargers are disabled and each battery can provide power for a minimum of 30 minutes.
D. The APU battery powers the APU standby bus through the APU hot battery bus and APU standby inverter. Both battery chargers are disabled and each battery can provide power for a minimum of 30 minutes. The main battery powers the main standby bus through the main hot battery bus and main standby inverter.

Q 61. (Freighter) With the Battery Switch ON, Standby Power Selector AUTO, and loss of power to the Captain’s transfer bus, what powers the standby power system?

A. The APU battery can provide a minimum of 30 minutes of power to the APU standby bus through the APU standby inverter.
B. The APU standby inverter is powered by DC Bus 3.
C. The APU battery can power the APU hot battery bus for a minimum of 60 minutes.
D. The APU standby bus is powered by AC Bus 1.

Q 62. (Passenger) Which of the following best describes what happens during the preflight with the Battery Switch ON and then selecting AUTO on the Standby Power Selector?

A. The standby bus becomes powered and the primary and secondary EICAS display on the upper CRT activates.
B. The standby bus powers the FMC, PFD and the ND.
C. Standby ignition for all engines is powered.
D. The standby bus becomes powered, the primary EICAS display on the upper CRT activates, the left ADC and left EFIS control panel are powered.

Q 63. (Passenger) With the Battery Switch ON, Standby Power Selector in AUTO, and AC Bus 3 not powered, how does flight critical equipment on the Standby Bus automatically receive AC power?

A. From the main battery charger.
B. From the standby inverter.
C. From the APU battery bus.
D. From TRU #3.

Q 63. (Passenger) Which of the following statements is true when the left Utility Power Switch is ON?

A. Two galley ELCUs and two utility ELCUs are powered.
B. Utility bus 1 and galley bus 1 are powered by AC bus 1, utility bus 2 and galley bus 2 are powered by AC bus 2.
C. Utility busses 1 and 2 are powered by AC bus 1, galley busses 1 and 2 are powered by AC bus 2.
D. One galley ELCUs and one utility ELCUs are powered.

Q 64. (Freighter) Which of the following statements is true when the left Utility Power Switch is ON?

A. One utility ELCUs are powered.
B. Utility busses 1 and 2 are powered by AC bus 1, AC bus 2 serves as a back-up source of power.
C. Utility bus 1 is powered by AC bus 1, and utility bus 2 is powered by AC bus 2.
D. One galley ELCUs and one utility ELCUs are powered.

Q 65. If the EICAS message ELEC GEN OFF 3 is displayed in flight and the airplane is otherwise operating normally, which of the following statements best describes the situation?

A. The number 3 generator control breaker must be manually selected open and the number 3 engine will continue to run normally.
B. The number 3 generator is no longer providing power to its respective AC bus.
C. AC bus 3 power is lost until the non-normal checklist is completed which will result in power being reconnected to the bus.
D. The number 3 IDG has high oil temperature.

Q 66. If AC bus 1 is unpowered with all engines operating, which of the following best describes the condition of the electrical system?

A. EICAS message ELEC AC BUS 1 is displayed.
B. EICAS message ELEC AC BUS 1 is displayed and Generator 1 OFF Light is illuminated.
C. EICAS message ELEC AC BUS 1 is displayed, Generator 1 OFF Light is illuminated and AC Bus 1 Isolation Light is illuminated.
D. Generator 1 OFF Light is illuminated and AC Bus 1 Isolation Light is illuminated.

Q 67. Which of the following statements best describes conditions during normal flight deck preparation with the APU running and both APU generators selected ON?

A. The Split System Breaker is open and the Split System Breaker Light is inhibited.
B. If one APU generator fails, the SSB remains open until external power is selected to power the unpowered synchronous bus.
C. Only APU generator 1 is providing power to the synchronous bus, APU generator 2 is in a standby mode to pick up the load if generator 1 fails.
D. The Split System Breaker is open and the Split System Breaker Light is illuminated.
E. If one APU generator fails, the Split System Breaker Light extinguishes.

Q 68. (Freighter) The Main Deck Cargo Handling Bus supplies power to which system(s)?

A. The fueling system.
B. Main deck cargo handling equipment and lighting and nose and side cargo doors.
C. Nose and side cargo doors and the fueling system.
D. Main deck cargo handling equipment and lighting.

Q 69. (Freighter) Which statement concerning the main deck cargo handling bus is most correct?

A. The Main Deck Cargo Handling Switch on the overhead maintenance panel provides power to the bus, but only on the ground.
B. The bus is powered when the External Power 2 is in use (APU not available).
C. When both external power 2 and APU generator 2 are available, APU generator 2 power is used.
D. The bus is powered when the External Power 2 AVAIL light is illuminated or APU GEN 2 AVAIL light is illuminated. The bus is unpowered when the APU generator 2 is not available and External Power 2 is in use.

Q 71. During flight deck preparation, the Standby Power Selector is normally placed in which position?

A. OFF
B. BAT
C. AUTO
D. ON

Q 72. When do the APU generator AVAIL lights illuminate?

A. When the APU N1 RPM exceeds 95%.
B. When the APU generator power quality is acceptable.
C. When the memo message APU RUNNING is displayed.
E. When the APU GEN ON light is extinguished.

Q 73. When engine # 4 is started with both APU generators connected, what will happen when the respective IDG voltage and frequency are acceptable?

A. Both APU generators are disconnected and IDG # 4 powers the entire electrical system.
B. Nothing, because there is no automatic switching of the IDGs.
C. The IDG powers its side of the synchronous bus and the previous power source is disconnected.

Q 74. Each (main/APU) battery is directly connected to its related hot battery bus.

A. True.
B. False.
C. True, but only as long as the Battery Switch is in the ON position

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