APU GEN SW

• ON: The APU Generator field is energized and the line contactor closes provided parameters are normal.
• OFF / R: The Generator field is de-energizied and the line contactor opens.
• Fault Light: Illuminates Amber accompanied by ECAM caution activation in the event of protection trip initiated by the associated Generator Control Unit.

BUS TIE SW

• AUTO: The five BUS TIE contactors open or close Automatically according to the priority logic in order to maintain power supply to all AC busses.
• OFF: The five BUS TIE contactors open.

Commercial SW

• OFF: Following equipment is shed.
  • Galleys
  • Passenger entertainment system
  • Cargo loading system
  • Electrical service
  • Escape slide lock mechanism ice protection
  • Water / /waste ice protection
  • Lavatory and cabin lights
  • Water heater.

Galley SW

• AUTO: The Galleys are normally supplied.
• OFF: All Galleys are shed and water / waste ice protection is lost.
• Fault Light: Illuminates Amber associated with ECAM in case of overload detection if the automatic shedding is not performed.

AC ESS FEED SW

• Normal: The AC ESS BUS is supplied from AC BUS 1.1.
• ALTN: The AC ESS BUS is supplied from AC BUS 2.4.
• Fault Light: Illuminates Amber accompanied by ECAM activation when the AC ESS BUS is not electrically supplied.

APU BAT SW
Controls the operation of the APU Battery Charge Limiter.

• AUTO: The APU Battery Charge Limiter Automatically controls the closure / opening of the line APU BAT contactor.
• OFF: The Battery Charge Limiter is not operating, the Battery line contactor is open.
• Fault Light: Illuminates Amber associated to ECAM caution activation as for BAT 1 or 2.

BAT 1 / 2 SW
Controls the operation of the corresponding Battery Charge Limiter.

• AUTO: The Battery Charge Limiter Automatically controls the connection / disconnection of the corresponding Battery to the DC BAT BUS by closure / opening of the Battery contactor.
• OFF: The Battery Charge Limiter is not operating, the DC ESS BUS is not connected to the Battery.
• Fault Light: Illuminates Amber accompanied by ECAM caution activation when the charging current for corresponding Battery increases at an abnormal rate or when the charge current exceeds a threshold.

BAT 1 / 2 or APU Voltage Indication
Selected Battery Voltage is indicated.

BAT 1 / 2 or APU SEL
Selects the Battery for voltage indication.

EXT A pb

• AVAIL Light: Illuminates Green provided external power parameters are normal.
• Momentarily Pressed:
  • If AVIAL light was ON:
    • The external power line contactor closes
    • The AVAIL light goes OFF
    • The ON light comes ON Blue
  • If the ON light was illuminated:
    • The external power line contactor opens
    • The ON light goes OFF
    • The AVAIL light comes ON

EXT B pb

• AVAIL Light: Illuminates Green provided external power parameters are normal.
• Momentarily Pressed:
  • If AVIAL light was ON:
    • Provided the APU generator is OFF the external power line contactor closes.
    • The AVAIL light goes OFF.
    • The AUTO light comes ON.
  • If the ON light was illuminated:
    • The external power line contactor opens.
    • The AUTO light goes OFF.
    • The AVAIL light comes ON.

IDG 1, 2, 3, 4 SW
Controls power supply for APU operation and protections.

• ON: Normally springloaded out. When pressed the IDG is disconnected from its drive shaft and can only be reconnected by maintenance action on ground.
• OFF: Illuminates Amber accompanied by ECAM caution activation.

GEN 1, 2, 3, 4 SW

• ON: The Generator field is energized and the line contactor closes provided electrical parameters are normal.
• OFF / R: The Generator field is de-energizied and the line contactor opens.
• Fault Light: Illuminates Amber accompanied by ECAM caution activation in the event of protection trip initiated by the associated Generator Control Unit.