Electrical Control Panel is part of A320 Overhead Panel
Commercial Switch #
AUTO – When the commercial switch is selected to AUTO all lights are extinguished. The AUTO position enables operation of the airplane’s commercial electrical loads (on some airplanes) that includes:
- Cabin and cargo lights
- Water and toilet systems
- Drain mast ice protection
- Galleys
- Passenger entertainment system, and
- In-seat power supply system
OFF – When the commercial switch is selected to OFF, the OFF light illuminates white and removes all commercial electrical loads as listed above.
Battery Indicator #
Two battery indicators labeled BAT 1 and BAT 2 provide battery voltage readings for each battery. The normal voltage is from 25 to 31 volts and discharge current from 0 to 5 amps.
On the ECAM ELEC page the battery voltage normally appears as a green color in the normal range, and becomes amber if the voltage is less than 25 V or greater than 31V. Battery current normally appears green and becomes amber if discharge current becomes greater than 5A.
Battery Switches #
AUTO – #
When the battery switches are selected to the AUTO all lights are extinguished. The AUTO selection enables the batteries to connect to the DC BAT bus during the following:
- APU starting
- Battery charging, and
- Below 100 knots on the ground with AC busses 1 and 2 not powered.
Two batteries, BAT 1 and BAT 2, are installed and each is connected directly to its respective HOT BAT bus. Each battery has its own battery charge limiter that monitors battery charging and controls it’s battery contactor.
FAULT –
The battery FAULT light illuminates amber when the charging current for the corresponding battery is outside normal limits causing the battery contactor to open.
OFF –
When the battery switches are selected to OFF, the battery charge limiter is not operating and the battery line contactor is open. The OFF light illuminates white if the DC BAT bus is powered. The HOT BAT busses remain powered regardless of battery switch selection.
AC Essential Feed Switch #
ALTN – Pushing the AC ESS FEED switch enables the AC ESS Bus to be powered via AC Bus 2 instead of AC Bus 1. A white boxed ALTN light will illuminate on the switch. Normally AC ESS Bus is supplied from AC Bus 1.
FAULT – An amber FAULT light indicates the AC ESS Bus is not electrically powered.
Gallery and Cabin Switch #
AUTO – When selected to AUTO all lights are extinguished on the GALY & CAB switch and arms the electrical system for automatically shedding electrical systems for a one generator operation. When the electrical system loses one generator it automatically sheds:
- The main galley bus
- In-seat power supply system, and to the passenger entertainment system
OFF – When the switch is selected to OFF, it turns off the power to:
- The main galley bus
- In-seat power supply system to the passenger entertainment system.
FAULT – An amber FAULT light indicates a generator load is above 100‰ of its rated output.
Integrated Drive Generator Switch #
GUARDED – The IDG switch is guarded and normally spring-loaded out. When pushed, the IDG is disconnected from its drive shaft and can only be reconnected by maintenance.
- The main galley bus
- In-seat power supply system, and to the passenger entertainment system
FAULT – An amber FAULT light indicates an IDG oil outlet overheat or low oil pressure. Inhibited below 14% N2.
Generator Switch #
ON – On is indicated when all lights are extinguished on the switch. Selecting the switch to ON energizes the generator field and the line contactor closes provided electrical parameters are normal.
OFF – When the OFF light illuminates white, the generator field is de-energized and the line contactor opens. The fault circuit is reset.
FAULT – When the FAULT light illuminates amber, a protection trip is initiated by the generator control unit (GCU), or the line contactor opens without selecting the GEN switch to OFF.
APU Generator Switch #
ON – The APU generator field is energized and the line contactor closes provided electrical parameters are normal and the EXT PWR line contactor is open. The bus tie contactor (1 and/or 2) automatically closes if generators 1 and/or 2 are not operating.
FAULT – When the FAULT light illuminates amber, a protection trip is initiated by the APU generator control unit (GCU), or the line contactor opens without selecting the APU GEN switch to OFF.
OFF – When the OFF light illuminates white, the APU generator field is de-energized and the line contactor opens. The fault circuit is reset.
Bus Tie Switch #
ON – When selected to AUTO all lights are extinguished on the switch, and the bus tie contactors open or close automatically to maintain power supply to AC buses 1 and 2. One contactor is closed when one engine-driven generator supplies the associated AC bus and the APU generator or external power supplies the other side. Both contactors are closed in case of one engine-driven generator, APU generator, or external power supply is connected.
OFF – The bus tie switch OFF light illuminates white when selected to OFF. Both bus tie contactors are open when selected to OFF isolating the other AC power.
External Power Switch #
ON – When the EXT PWR AVAIL light is illuminated, pushing the EXT PWR switch illuminates the blue ON light, closes the external power line contactor, and the AVAIL light goes off.
AVAIL – A green AVAIL light illuminates when external power is plugged in and the electrical parameters are normal. On the ECAM ELEC page the EXT PWR indication normally appears white. Voltage (110V to 120V) and Frequency (390Hz to 410Hz) appears green when in normal range, and is amber when it exceeds the normal range.
