Electrics

Question 1

What is the output of the A320 elec sys in normal conditions?

Answer 1

90kVA at 115-200V, and a 28V DC battery system.

Question 2

In normal conditions, how is power generated by the electrical system?

Answer 2

In normal conditions, two engine driven IDG’s power AC BUS 1 and AC BUS 2.
AC buses power their respective DC buses through dedicated TR.
AC bus 1 powers the AC ESS BUS and DC ESS BUS is powered by DC BUS 1, therefore load in GEN1 generally 10% greater than GEN2.

Question 3

What is the bus tie?

Answer 3

Allows power transfer to opposite elec side, and how APU can power both sides.

Question 4

In abnormal situations, how is electricity generated and what is powered?

Answer 4

The RAT powers the blue hydraulic system which drives the emergency generator by an electric motor. This supplies the AC ESS BUS, and the DC ESS BUS via the ESS TR.

Question 5

What is the output of the emergency generator?

Answer 5

5kVA

Question 6

When will the emergency generator deploy automatically, and what happens to elec sys while no generators are online?

Answer 6

RAT deploys automatically following failure of AC BUS 1 and AC BUS 2. RAT takes 10secs to come online, during this time A/C is on Battery power only.
BAT 1 powers AC ESS BUS via SI, BAT 2 powers DC ESS BUS.

Question 7

What are the load limitations of the elec sys?

Answer 7

100% load = 90kVA

Question 8

What QRH advisories are there for the elec sys?

Answer 8

Emer elec config summary
Emer elev config sys remaining
C/B tripped

Question 9

On what occasions will the batteries connect to the battery bus?

Answer 9

1. APU battery start
2. Flight on batteries only (loss of AC BUS 1 + 2 before emergency gen online, and in flight when a/c speed falls below 100kts and RAT stalls)
3. Recharge cycle

Question 10

What types of circuit breakers are there?

Answer 10

Monitored and Unmonitored. Monitored are green and when tripped will generate an ECAM alert after 1 minute.

Question 11

Are there any circuit breakers that cannot be reset?

Answer 11

WTB, have red sleeves.

Question 12

How will elec sys reconfigure after AC BUS 1 failure?

Answer 12

Should reconfigure automatically, AC BUS 2 will supply AC ESS BUS, and DC ESS BUS via ESS TR, both via AC ESS FEED.
DC BUS 2 supplies DC BUS 1 and DC BAT BUS automatically after 5s

Question 13

What are the major consequences of a TR 1 + 2 failure?

Answer 13

DC BUS 1 + 2 failure

Question 14

What is emergency electrical configuration?

Answer 14

Emer elev config occurs following loss of AC BUS 1 + 2. Elec power supplied by emergency generator at 5kVA to AC ESS BUS, which powers DC ESS BUS via ESS TR.
CM1 only pilot that can fly in this config.

Question 15

What is elec smoke config?

Answer 15

Like emer elec config but have a fuel pump in each inner tank running to maintain fuel pressure (no gravity fuel feeding) and intended as temporary configuration - can recover electrics before landing.
Commander will choose to enter this condition to protect a/c against undetermined source of elec fire situation.
Proc in QRH.

Question 16

If aircraft in flight on batteries only, what do the batteries supply?

Answer 16

BAT BUS 1 supplies AC ESS BUS through SI
BAT BUS 2 supplies DC ESS BUS