B727 Questions Electrical
Revised 28-Feb-2001
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  1. What is the primary electrical power, volts, phase, hertz and current
  2. What converts variable input speed from the engine accessory pad to a constant RPM output to the generator.
  3. AC power to the airplane may be supplied by the engine driven generators and what other sources.
  4. CSD oil cooler efficiency is determined by observing what.
  5.  To prevent the disconnected generator from being motorized by paralleled generators the disconnect switch also trips what.
  6. The voltage regulator adjusts what to control the voltage output of an isolated generator
  7. To reduce the output of a generator to a minimum. What would you trip.
  8. What connects a generator to it's load bus
  9. To equalize the loads on the generators. The load busses are connected together by what
  10.  Damage to the generators might occur if they are not what
  11. In order for a generator to be able to supply essential power. its what must be closed
  12. The standby bus can be powered from the essential bus or by what other means.
  13. The AC transfer bus can be powered from what two sources
  14. If residual voltage is 10 to 17 volts, you know the generator is doing what.
  15.  If the synch lights are out. The generator selected is in what with the synch bus.
  16. Normal DC power is supplied by what
  17. The battery charger receives power from the bus
  18. If  TR 1 fails.  DC bus number 1 will be powered by
  19. Failure of a TR is indicated by what, indicating zero
  20.  The battery bus is normally powered by What
  21. With the airplane not powered, What will be powered from the Battery
  22. In flight normally the hot battery bus is powered by what
  23. What two sources can power the battery transfer bus
  24. What illuminates with the loss of essential power
  25.  When paralleling manually, the bus tie breaker should be closed when the synch lights are
  26. If all generators are lost while on the ground, the battery switch should be checked on and what  should be turned on/opened 
    Answer the following as True or False
  27. In order to check the battery, power to the battery charger should be interrupted.
  28. When the APU generator breaker is closed, the bus tie breakers should remain open
  29.  The CSD disconnect switches should be selected to DISCONNECT to check their operation during flight.
  30. Prior to engine start the electrical load should be reduced
  31. Immediately after engine start. When the first engine driven generator is connected and the APU generator drops off line, essential power will be lost
    Abnormal & Emergency  Procedures
  32. If all generators are lost in flight. The first action to be taken is to
  33. When can the generator drive be reconnected
  34. For landing with only two generators operating how many packs on
  35. One generator inoperative when should you turn on the 2nd pack
  36. With only one generator operating before flap extension do what.


  1. 115 Volts, 3 Phase, 400 Hz, AC
  2. CSD (Constant Speed Drive)
  3. APU and External Power
  4. "IN" Temperature
  5. Trips the Generator Breaker
  6. Excitation Current
  7. Field Relay
  8. Generator Breaker
  9. Sync Bus (tie bus)
  10. In Phase
  11. Field Relay
  12. Inverter, Battery Bus
  13. No3 Ac Load Bus or External Power
  14. Rotating
  15. In Phase
  16. Transformer - Rectifier (TR's)
  17. AC Transfer Bus
  18. No2 TR
  19. DC Amps Indicator
  20. Essential DC Bus
  21. Hot Battery Bus, Hot Battery Transfer Bus
  22. Battery, Battery Charger
  23. Battery Bus, External DC Bus (External power)
  24. Red Steady Light At FE Panel, Flashing Red at Fwd Instrument Panel
  25. Out
  26. Brake Interconnect
  27. True, Yes you need to
  28. False
  29. False, If you did your a dickhead can only be reset on the ground
  30. True, Loads Reduced To Minimum
  31. False, Will Only be affected If you Trip The APU Field Relay
  32. Essential Power Selector, Standby
  33. On The Ground
  34. One
  35. After Flap Retraction and the Pack Fans Are Off
  36. Turn Off Both Packs, Depressurize
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