Display Selector
Ground Power and Bus Switching Panel
with associated APU Lights and Indicators
APU GEN (APU Generator) Switch

Three position switch, spring–loaded to neutral.

With the APU powering both AC Transfer Busses.

OFF –
  • Moving a single APU GEN switch to OFF illuminates the
    related SOURCE OFF light. The APU continues to power
    the AC Transfer Busses.

  • Subsequently moving the opposite APU GEN switch to
    OFF disconnects the APU generator from the tie bus and
    removes APU power from  the AC Transfer Busses.

ON -
  • Moving a single APU GEN switch to ON connects both AC
    Transfer Busses to the APU generator.

  • Subsequently moving the opposite APU GEN switch to
  • ON extinguishes the related Source Off light.