AIRBUS A320 EQUIPMENT ELECTRICAL SUPPLY

The Airbus A320 aircraft electrical power system consists of a three-phase 115/200 V 400 Hz constant-frequency AC system and a 28 V DC system. In normal configuration, the electrical power system provides AC power. A part of this AC power is converted into DC power through TRs for certain applications.

The Airbus A320 electrical power system is constituted of 2 engine generators and 1 APU generator. Each generator can provide AC power to all electrical bus bars. In the event that normal AC power is not available, an emergency generator can provide AC power. In the event that all AC power is not available, the electrical power system can invert DC power from the batteries into AC power through static inverter.

ELECTRICAL BUSES

AC BUS 1 – supplied by IDG 1
AC BUS 2 – supplied by IDG 2
AC ESS – supplied by AC BUS 1/2
AC ESS SHED – supplied by AC ESS BUS
DC BUS 1 – supplied by TR 1, and TR 1 by AC BUS 1
DC BUS 2 – supplied by TR 2, and TR 2 by AC BUS 2
DC ESS – supplied by DC BAT BUS, and DC BAT BUS supplied by DC BUS 1/2
DC ESS SHED – supplied by DC ESS
HOT BUS 1 – supplied by BAT 1
HOT BUS 2 – supplied by BAT 2

ELECTRICAL SUPPLY OF EQUIPMENT

Here is a list of equipment that is being supplied by electrical buses in both normal and emergency conditions. Follow these bus equipment list according to ATA chapter.

21 AIR CONDITIONING – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
AIR COND SYS CONT	1 lane 1	AC1	DC1
	2	AC2			X
	2 lane 1	AC1	DC1
	2	AC2	DC2
PACK 1 VALVE CLOSURE					SHED
PACK 2 VALVE CLOSURE			DC2
RAM AIR INLET					X
CAB PRESS CONT	1				X
	2		DC2
	MANUAL CTL		DC BAT
CABIN FANS	1	AC1	DC1
CABIN FANS	2	AC2	DC2
AEVC			DC1		SHED
VENT AVIONIC FANS	FAN BLOWER	AC1	DC1
VENT AVIONIC FANS	EXTRACT	AC2			SHED
GND COOL UNIT *	UNIT FAN CONTROL	AC2 AC1
CARGO VENT CONT *			DC BAT
CARGO HEAT CONT *			DC BAT
CARGO VENT/HEAT FANS(S) *		AC 1

22 AUTO FLIGHT – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
FMGC	1				SHED
FMGC	2		DC2
MCDU	1			SHED
	2	AC2
	3 *	AC1
FCU	1				X
FCU	2		DC2

23 COMMUNICATION – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
RADIO COMMUNICATIONS	VHF1				X
	VHF2		DC2
	VHF3 *		DC1
	HF1 *			SHED
	HF2 *	AC2
	RMP1				X
	RMP2		DC2
	RMP3 *		DC1
	CAPT ACP				X
	F/O ACP				X
	THIRD ACP		DC1
	FOURTH ACP *		DC1
	SELCAL		DC1
	FLT INTERPHONE				X
	CAPT LOUDSPEAKER				X(1)
	F/O LOUDSPEAKER				X(1)
	EXT HORN					HOT 2
CABIN INTERCOM DATA SYS	CIDS1		GND/FLT		X
	CIDS2		GND/FLT		X
	DEU (A/B)		GND/FLT		X
CVR	CVR CTL				X
CVR	CVR				X
ACARS *		AC1
SATCOM *		AC1
Note : (1) Normal supply is from DC ESS BUS. DC BUS 1 supplies CAPT (or F/O) loudspeaker when AUDIO SWITCHING selector is set to CAPT (or F/O) on 3. * If installed.

25 COCKPIT & CABIN – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
FLIGHT DECK	CAPTAIN SEAT motors *	AC1
	F/O SEAT motors *	AC2
	FOOT WARMERS *	AC2
COCKPIT DOOR SECURITY SYSTEM	COCKPIT DOOR LOCKING SYSTEM *	DC2
	COCKPIT DOOR LOCKING SYSTEM BACKUP *	DC1
	COCKPIT DOOR SURVEILLANCE SYSTEM *	DC1
IN SEAT POWER SUPPLY SYSTEM	IN SEAT POWER SUPPLY *	AC2

26 FIRE PROTECTION – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
ENG/APU FIRE DETECTION	ENG 1 LOOP A				X
	ENG 1 LOOP B		DC2
	ENG 2 LOOP A		DC2
	ENG 2 LOOP B				X
	APU LOOP A		DC BAT
	APU LOOP B		DC BAT
ENG 1/2 FIRE EXTINGUISHING	BTL 1 SQUIB A					HOT 1
	BTL 1 SQUIB B					HOT 2
	BTL 2 SQUIB A		DC 2
	BTL 2 SQUIB B		DC 2
APU FIRE EXTINGUISHING	BTL SQUIB A					HOT 1
	BTL SQUIB B		DC BAT
	APU AUTO EXT		DC BAT
CARGO & LAVATORIES	CIDS CH 1				X
	CIDS CH 2		DC 2
	FWD/AFT CARGO EXTING BOTTLES		DC BAT

27 FLIGHT CONTROLS – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
MAIN FLT CTL COMPUTERS	ELAC 1				X	HOT 1 (1)
	ELAC 2		DC2			HOT 2 (1)
	SEC 1				X	HOT 1 (1)
	SEC 2		DC2
	SEC 3		DC2
	FAC 1			X	SHED
	FAC 2	AC2	DC2
	FCDC 1				SHED
	FCDC 2		DC2
PITCH TRIM	MOTOR 1		DC2			HOT 2 (1)
	MOTOR 2				X
	MOTOR 3		DC2
RUDDER TRIM	MOTOR 1				X
	MOTOR 2		DC2
	INDIC		DC2
RUDDER TRAVEL LIMIT	MOTOR 1				X
RUDDER TRAVEL LIMIT	MOTOR 2		DC2
FLAPS SLATS COMPUTERS	SFCC 1 slats				X
	SFCC 1 flaps				X
	SFCC 2 slats		DC2
	SFCC 2 flaps		DC2
Note : (1) Standby supply.

28 FUEL – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
FQI	CH 1				SHED	(1)
FQI	CH 2		DC2			(1)
INNER TANK PUMPS	L 1	AC1 (3)	DC1		X (2) (3)
	L 2	AC2	DC2
	R 1	AC1 (3)	DC1		X (2) (3)
	R 2	AC2	DC2
CTR TK PUMPS *	1	AC1	DC1
CTR TK PUMPS *	2	AC2	DC2
CROSS FEED VALVE	MOT 1				SHED
CROSS FEED VALVE	MOT 2		DC2
ENGINE LP VALVES	ENG 1 MOT 1				X
	ENG 1 MOT 2		DC2
	ENG 2 MOT 1				X
	ENG 2 MOT 2		DC2
XFR VALVES	L1				SHED
	L2		DC2
	R1				SHED
	R2		DC2
APU	PUMP			AC STAT INV or AC ESS SHED		HOT 1
APU	LP VALVE		DC BAT			HOT 1
REFUEL VALVES			DC2			(1)
Note: (1) HOT BUS supplies power during refueling on battery. (2) This occurs, if DC BUS 1 is lost. (3) In smoke configuration (GEN 1 LINE pushbutton OFF), inner tank pumps 1 are supplied directly by IDG (instead of AC 1) and pump relays by DC ESS (instead of DC 1).

29 HYDRAULIC ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
ENG 1 driven PUMP control			DC1
ENG 2 driven PUMP control			DC2
ENG 1 FIRE shut off valve					X
ENG 2 FIRE shut off valve					X
BLUE ELEC PUMP	power	AC1
BLUE ELEC PUMP	control				X
YELLOW ELEC PUMP	power	AC2(1)
YELLOW ELEC PUMP	control		DC2
Power Transfer Unit			DC2
LEAK MEASUREMENT VALVES			DC GRND/FLT
RAT	Manual control					HOT 2
RAT	Auto control					HOT 1
Note : (1) or from external power.

30 ICE AND RAIN PROTECTION – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
WING ANTI ICE	L and R SHUT-OFF VALVES				SHED
ENG ANTI ICE CLOSURE VALVE	1		DC1
ENG ANTI ICE CLOSURE VALVE	2		DC2
WHC	1		DC1
WHC	2		DC2
WINDOW HEATING POWER	L	AC1
WINDOW HEATING POWER	R	AC2
PHC	CAPT				X
	F/O		DC2
	STBY		DC1
STATICS	CAPT and STBY		DC1
STATICS	F/O		DC2
PITOT	CAPT			X (1)
	F/O	AC2
	STBY	AC1
AOA	CAPT			SHED
	F/O	AC2
	STBY	AC1
TAT	CAPT	AC1
TAT	F/O	AC2
WIPER	CAPT		DC1
WIPER	F/O		DC2
RAIN REPELLENT *	CAPT				X
RAIN REPELLENT *	F/O		DC2
ICE DETECT SYS *	DETECTOR 1	AC1
ICE DETECT SYS *	DETECTOR 2	AC2
Note : (1) When AC1 and AC2 are lost and AIR DATA is switched to “ CAPT 3”, the STBY pilot is switched to AC ESS bus and CAPT pitot heating is lost.

31 INDICATING / RECORDING SYSTEMS – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
DU	CAPT PFD			X
	CAPT ND			SHED
	F/O PFD	AC2
	F/O ND	AC2
	UPPER ECAM DU			X
	LOWER ECAM DU	AC2
DMC	DMC 1			X
	DMC 2	AC2
	DMC 3	AC1		X (1)
FWC	FWC 1			X
FWC	FWC 2	AC2
SDAC	SDAC 1			X
SDAC	SDAC 2	AC2
ECP	ECP				X
FDIU/QAR *		AC2
CLOCK					X	X
Note : (1) in case of EIS DMC switching to CAPT/3, with AC BUS 1 failed.

32 LANDING GEAR – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
LANDING GEAR	LGCIU 1		GRND/ FLT		X
	LGCIU 2		GRND/ FLT
	SAFETY VALVE				X
	L/G INDICATOR PANEL			SHED (1)	X
BRAKES	BSCU CH 1	AC1	DC1
	BSCU CH 2	AC2	DC2
	ABCU				X	X
	PARK BRK CTL *		GRND/ FLT			HOT1
	PRESS INDICATOR				X
	BRK FAN CTL *		DC2
	COOLING FANS * (Wheels 1, 2, 3, 4)	AC2	DC2
	COOLING FANS * (bogie : Wheels 5, 6, 7, 8)	AC1	DC1
TYRE PRESS	TIRE PRESS IND UNIT *		DC1
Note : (1) The AC STAT INV supplies the landing gear indicator panel when the main generators are lost and the emergency generator is not running.

33 LIGHTS – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
COCKPIT LIGHTS	Dome light L		DC GND/ FLT
	Dome light R				X
	Console light L		DC1
	Console light R		DC2
	Main INST panel L				X
	Main INST panel R		DC1
	STBY compass/ice ind				X
	Supplementary reading light		DC1
	Pedestal light		DC1
	Reading light L		DC1
	Reading light R		DC2
	Briefcase light L		DC1
	Briefcase light R		DC2
	Map holder light L		DC1
	Map holder light R		DC2
	Floor light		DC1
	INST, panels-integral light	AC1
	Annunciator light	AC1, 2 and AC STAT INV
	Annunciator light test/dim		DC2
EXTERIOR LIGHTS	Navigation lights	GRD/FLT
	Landing lights L	AC1
	Landing lights R	AC2
	RWY turn off lights L	AC1		DC 2 (1)
	RWY turn off lights R	AC2		DC 2 (1)
	Taxi and TO lights	AC1		DC 2 (1)
	Taxi and TO lights	AC2		DC 2 (1)
	Logo lights L *	AC1		DC 2 (1)
	Logo lights R *	AC2		DC 2 (1)
	Beacon lights Upper	AC1
	Beacon lights Lower	AC2
	Strobe lights *	AC2
	Wing lights R	AC1
	Wing lights L	AC2
	Note : (1) Supply for the light control.
CABIN LIGHTING		AC1 AC2 and GRND/ FLT				SHED (1)
CABIN LIGHTING	Note : (1) Standby supply (Refer to FCOM Emergency Lighting Control Logic)

34 NAVIGATION – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
ADIRU	ADIRU 1			X		HOT 2 (1)
	AOA RESOLVER 1			X
	ADIRU 2	AC2				HOT 2 (2) during 5 min
	AOA RESOLVER 2	AC2
	ADIRU 3	AC1				HOT 1 (3)
	AOA RESOLVER 3	AC1
	Note : (1) Backup supply. (2) Backup supply for 5 min. (3) Backup supply, when ATT HDG is in the CAPT 3 position. Backup supply for 5 min, when the ATT HDG is in the NORM or F/03 position.
NAVAIDS	MMR 1			X
NAVAIDS	MMR 2	AC 2
STD BY INST	HORIZON				X	HOT 1 (1)
	ALTIMETER				SHED
	COMPASS				X
	Note : (1) Backup supply.
NAVAIDS	VOR 1			X
	VOR 2	AC 2
	MMR 1			X
	MMR 2	AC 2
	ADF 1			SHED
	ADF 2 *	AC 2
	DME 1			SHED
	DME 2	AC 2
RADIO ALTIMETER	RA 1	AC1
RADIO ALTIMETER	RA 2	AC2
ATC	ATC 1			SHED
ATC	ATC 2	AC 2
WEATHER RADAR	WX 1	AC1
WEATHER RADAR	WX 2 *	AC2
GPWS		AC1
TCAS *		AC1

35 OXYGEN – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
CREW OXY CTL						SHED
PAX OXYGEN	ACTUATION				SHED
PAX OXYGEN	AUTOCONTROL					SHED

36 PNEUMATIC – ELECTRICAL SUPPLY

EQUIPMENT		NORM		EMER ELEC
EQUIPMENT		AC	DC	AC ESS	DC ESS	HOT
BMC	1				SHED
BMC	2		DC2
BLEED VALVES, HP VALVES AND FAN AIR VALVES	ENG 1				SHED
BLEED VALVES, HP VALVES AND FAN AIR VALVES	ENG 2		DC2
X-BLEED VALVE	AUTO CONTROL		DC2
X-BLEED VALVE	MANUAL CONTROL				SHED

38 WATER / WASTE – ELECTRICAL SUPPLY

EQUIPMENT	NORM		EMER ELEC
EQUIPMENT	AC	DC	AC ESS	DC ESS	HOT
POTABLE WATER SYS		GND/FLT
WATER HEATER	AC2
WATER DRAINING		GND/FLT
VACUUM GENERATOR	AC2
PRESSURIZED WATER SYS	AC2
FLUSH CONTROL UNITS		GND/FLT
VACUUM SYS CONTROLLER		GND/FLT

45 MAINTENANCE SYSTEM – ELECTRICAL SUPPLY

EQUIPMENT	NORM		EMER ELEC
EQUIPMENT	AC	DC	AC ESS	DC ESS	HOT
CFDS		DC1

46 INFORMATION SYSTEMS – ELECTRICAL SUPPLY

EQUIPMENT	NORM		EMER ELEC
EQUIPMENT	AC	DC	AC ESS	DC ESS	HOT
ATSU	ATSU 1	AC1	DC1

49 APU – ELECTRICAL SUPPLY

EQUIPMENT	NORM		EMER ELEC
EQUIPMENT	AC	DC	AC ESS	DC ESS	HOT
ECB SUPPLY			X
STARTER MOTOR			X
Note: When the system is in electrical emergency configuration, battery contactors automatically close for a maximum of 3 min when the APU MASTER SW is ON. When the aircraft is in flight, and when the system is in electrical emergency configuration, the APU start is inhibited for 45 s.

52 DOORS – ELECTRICAL SUPPLY

EQUIPMENT	NORM		EMER ELEC
EQUIPMENT	AC	DC	AC ESS	DC ESS	HOT
DOORS and SLIDES CTL		DC BAT (1)			HOT2 (1)
CARGO DOORS		DC GRND FLT
AIR STAIRS		DC2			HOT2 (2)
Note : (1) STBY supply (normally supplied by the EMER PWR SUPPLY UNIT) (2) STBY supply