ELEC Panel (Odd)

Question 1

What is the minimum battery voltage?

Answer 1

25.6V

Question 2

What would a pilot do if BAT voltage is 25.5 or below on originating preflight?

Answer 2

Charge the batteries with external power by selecting BAT pushbuttons to AUTO

Question 3

How long should the batteries be charged?

Answer 3

20 minutes, then recheck the voltage

Question 4

Explain how to conduct the BAT check. What if it fails the test?

Answer 4

• Select ELEC on ECAM
• Turn BAT 1 & 2 OFF then ON
• Check BAT charge current is < 60 amps and decreasing within 10 seconds
• If it fails the test, wait until the end of the charging cycle, and repeat the test

Question 5

The following question should provide a better understanding of the
electrical power system. While the question may not be asked in the
same manner, an operational understanding is expected.

Describe the electrical power system.

Answer 5

• The electrical power system consists of a three-phase 115/200-volt 400
  hertz constant frequency AC system and a 28-volt DC
• Normally, the system produces alternating current, some of which is then transformed into direct current for certain applications.
• Each of the aircraft’s three generators can supply the whole network.
• If all normal AC generation is lost, an emergency generator can supply AC power.
• If all AC generation is lost, the system can transform DC power from the batteries into AC power.

Question 6

If all AC power is lost, what happens?

Answer 6

DC power from the batteries is converted into AC

Question 7

What would be an expected indication in the GEN pushbuttons prior to engine start?

Answer 7

FAULT indication

Question 8

Define and describe an IDG.

Answer 8

• Integrated Drive Generator
• Takes variable engine output and gives a constant output

Question 9

How would a pilot disconnect an IDG?

Answer 9

Lift the red guard and push the IDG pushbutton, being careful not to hold the pushbutton for longer than three seconds.

Question 10

How would an IDG be reconnected?

Answer 10

This cannot be done by the flight crew – it is a maintenance function

Question 11

Describe the function of the BUS TIE in AUTO.

Answer 11

• Allows a single source to power AC BUS 1 and 2
• Allows connection of the APU GEN or EXT power to system
• Inhibits multiple sources connected simultaneously

Question 12

If GEN 1 fails to supply AC Bus 1, what happens?

Answer 12

Gen 2 (or APU GEN if available) powers the system through the bus tie

Question 13

How is the AC ESS bus normally powered?

Answer 13

From AC bus 1

Question 14

If AC BUS 1 fails, how is the AC ESS bus powered?

Answer 14

AC bus 2 automatically feeds the AC ESS bus

Question 15

What indication will be present on the ELEC panel that AC BUS 2 is feeding the AC ESS bus?

Answer 15

AC ESS FEED ALTN light illuminated only if the switch is manually selected

Question 16

What does a GALLEY fault light indicate?

Answer 16

At least one generator load is above 100% rated output

Question 17

Explain the AUTO function of the GALLEY pushbutton.

Answer 17

Sheds main galley if only 1 GEN is available

Question 18

How is the BATTERY BUS normally powered?

Answer 18

DC BUS 1 through the DC tie contactor

Question 19

What buses are powered by the EMER GEN?

Answer 19

• AC ESS BUS
• AC ESS SHED
• DC ESS BUS by the ESS TR
• DC ESS SHED

Question 20

What does a BAT FAULT light indicate?

Answer 20

• Battery charging current outside limits
• BAT contactor opens.

Question 21

When are the batteries connected to the battery bus?

Answer 21

• APU start
• Battery charging
• AC BUS 1 & 2 not powered and airspeed below 100 knots