Airbus A320 Electrics

Question 0

What are the specifications of the DC System?

Answer 0

28 Volts

Question 1

What are the specifications of the AC System?

Answer 1

3 phase

115/200 Volts

400 Hz

Question 2

What are the ratings of the Engine & APU Driven Gens and the Emergency Gen?

Answer 2

Engine & APU Driven : 90 kVA

Emergency Generator : 5 kVA

Question 3

How is the Emergency Generator driven?

Answer 3

By the Blue Hydraulic System.

Question 4

How is constant frequency obtained from the Engine & APU Driven Generators?

Answer 4

IDGs : Integrated (Constant Speed) Drive Units

APU : Constant Speed APU

Question 5

The Static Inverter can supply the AC ESS Busbar.

What is its Source & what does it supply?

Answer 5

Source : Battery 1

Supplies : (part of) the AC ESS Bus

Question 6

When will the Static Inverter be Energised from the Battery even if the Battery Switch is OFF?

Answer 6

If Aircraft speed exceeds 50 kts AND the only source of power is the Batteries,

Battery 1 will supply the Static Inverter irrespective of Battery p/b position.

Question 7

How many TRs are there?

Answer 7

3

Question 8

How many amps can a TR supply?

Answer 8

200 Amps

Question 9

In Normal Operations which TRs are in use?

Answer 9

TR1 and TR2 only.

Question 10

How many batteries are there?

Answer 10

2

Question 11

What is a BCL?

Answer 11

Battery Charge Limiter

Question 12

What do the following colours on Cb collars mean:

• Green
• Black
• Red
• Yellow?

Answer 12

Green - Monitored by ECAM

Black - Not ECAM Monitored

Red - Must not be pulled

Yellow - may be pulled when on batteries only (Early A320 only.)

Question 13

At any one time there my be 4 main sources of AC Power available :

• GEN1, GEN2, APU GEN & EXT PWR.

What is the order of Preference of Supply?

Answer 13

To either AC Bus,

1. Onside GEN, then
2. EXT PWR (if EXT PWR p/b pressed), then
3. APU, finally
4. Offside GEN.

Question 14

Can any of the electrical sources be connected in parallel?

Answer 14

NO.

The Bus Ties will prevent this.

Question 15

In Normal Operations, which AC Busbars are supplied by GEN1 and GEN2?

Answer 15

GEN1: AC1 and through AC1 the ESS AC.

GEN2 : AC2

Question 16

In Normal Operations, how are the TRs supplied?

Answer 16

TR1 supplied from AC1

TR2 supplied from AC2

ESS TR is not in use.

Question 17

In Normal Operations what do the TRs supply?

Answer 17

TR1 supplies : DC Bus 1, Battery Bus (through DC1) and ESS DC (through Battery Bus)

TR2 supplies : DC Bus 2

ESS TR supplies : nothing

Question 18

In Normal Operations, what do the Batteries supply?

Answer 18

Just the Hot Battery Busbars.

Question 19

What is the Normal Source of supply of the “Battery” Busbar?

Answer 19

TR1

Question 20

When the AC and DC GROUND/FLIGHT busses are being supplied directly from EXT PWR, does EXT PWR also power the rest of the aircraft Electrical System?

&

What component of the Electrical System is also required to enable DC GROUND/FLIGHT to be energised?

Answer 20

NO

&

TR2

Question 21

In Normal Operations are the AC and DC GROUND/FLIGHT busses powered and if so from what source?

Answer 21

YES

AC from AC2

DC from DC BUS 2

Question 22

If GEN1 or GEN2 fails in flight, what pilot action is required to ensure that Supplies are maintained to the Electrical System?

Answer 22

None.

The opposite generator, or the APU Gen will replace the failed generator automatically.

Question 23

If AC1 Fails, what pilot action is required to regain supply to it?

Answer 23

If it does not automatically recover, Use the AC ESS FEED p/b.

This connects AC ESS to AC2 rather than AC1 and hopefully restores it.

AC BUS 1 normally supplies the AC ESS BUS, and, via the TR1, the DC ESS BUS.
In the case of an AC BUS 1 FAULT, the AC ESS BUS and the DC ESS BUS will automatically recover, due to the fact that the AC BUS 2 will automatically supply the AC ESS BUS.
If AC BUS 2 does not automatically supply the AC ESS BUS, the flight crew can recover the AC ESS BUS and the DC ESS BUS by setting the AC ESS FEED pb-sw to ALTN, as requested by the AC ESS BUS FAULT ECAM procedure.