Electrical

Question 1

AC BUS 1 Power Hierarchy

Answer 1

1. Generator 1
2. APU Generator
3. External B
4. External A
5. Generator 2

Question 2

AC BUS 2 Power Hierarchy

Answer 2

1. Generator 2
2. External A
3. APU Generator
4. External B
5. Generator 1

Question 3

If AC BUS 1 is lost, how is the AC ESS BUS powered?

Answer 3

AC ESS BUS (and ESS TR) is powered by AC BUS 2 via the ESS XFEED

Question 4

In emergency electrical config, if the green hyd is powered by the engine-driven pumps, the emergency generator supplies what?

Answer 4

1. AC ESS BUS
2. AC ESS SHED
   and through the ESS TR:
3. DC ESS BUS
4. DC ESS SHED

Displays: PFD (capt), ND(capt), E/WD

Question 5

If green hydraulic is powered by the RAT the emergency gen supplies….?

Answer 5

1. AC ESS BUS
2. DC ESS BUS

Displays: PFD, E/WD

Question 6

When emergency gen is not available, the batteries supply?

Answer 6

1. DC ESS BUS
2. DC LAND RECOVERY (if pushbutton in)
   and through the STAT INV
3. AC ESS BUS
4. AC LAND RECOVERY (if pushbutton in)

Question 7

COMMERCIAL pb

Answer 7

Everything behind the cockpit. Controls power to galleys, cargo loading system, electrical service, escape slide lock mechanism ice protection, drain mast ice protection, lav/cabin lights, water heater, in-seat power supply, in-flight entertainment.

Question 8

IDG 1 (2) pb (pushed in & fault light)

Answer 8

Pushing it disconnects IDG from its drive shaft. Only Mx can reset it. Damage may occur if pushed more than 3sec..
Fault: Associated ECAM displayed for: IDG oil outlet overheat (above 185°C) or IDG oil pressure low.

Question 9

Why does EXT A pb say “ON” and EXT B say “AUTO”?

Answer 9

EXT B has lower priority than the APU for BOTH AC BUS 1 and AC BUS 2. The “AUTO” signifies that it will connect/disconnect automatically based on APU Generator status (it will AUTOMATICALLY take over if AVAIL and APU Gen fails). EXT A has higher priority over the APU for power supply to AC BUS 2 and therefore will be supplying power AC BUS 2 when selected ON (assuming EXT A ground power is available and ENG 2 not running).

Question 10

Initial power-up battery voltage check. Min voltage and how to recharge.

Answer 10

Voltage should be above 25.5 V (50% charge). If less charge off EXT power for 20 min then check again.

Question 11

APU battery voltage below ____ risks an aborted start.

Answer 11

23.5V

Question 12

We can operate on batteries only for a minimum of _____ minutes.

Answer 12

30 minutes

Question 13

GALLEY pb

Answer 13

Sheds Galley power, water/waste (drain mast) ice protection, and heating floor panels.

Question 14

What items are connected to the Hot Battery Bus while on the ground and remain powered at all times

Answer 14

1. Clock
2. Battery Voltage indicator window