AC Generator

Any actual generator failure or generator over-voltage causes the generator to be removed from the AC system until the condition is corrected. Failure of the AC generator, shown by the AC generator-off caution light coming on, causes loss of all AC power.

Note

If a flame-out occurs under these conditions, attempt an air start if remaining altitude and fuel permit.

The instrument AC power-off caution light also comes on to show loss of the 3-phase instrument bus. generator failure, the standby instrument inverter switch should be moved to ON, to restore power to the 3-phase instrument bus (and to the single-phase instrument AC bus which is powered by the 3-phase instrument bus). Once power is restored to these busses, the instrument AC power-off caution light extinguishes. There is no alternate means of powering the main 3-phase bus.

AC Generator Reset

If the AC generator fails, try to return the generator to service as follows:

  1. Standby Instrument Inverter Switch—ON
  2. AC Generator Switch—RESET momentarily, then ON
  3. If AC generator caution light extinguishes, Standby Instrument Inverter Switch—OFF

  4. If caution light remains on, repeat reset procedure up to twice.

    Caution

    If the AC generator drive unit fails in such a manner as to break the case, oil in the unit is pumped overboard or into the engine intake duct, resulting in smoke or fumes in the cockpit.

If the generator light remains on after three reset attempts, assume that AC generator drive unit has failed. Proceed as follows:

  1. AC Generator Switch—OFF
  2. Stabilize engine RPM
  3. Land as soon as practical.