CBT - ELEC

Question 1

What does the electrical network mainly split into?

Answer 1

• Normal Network (115 V AC 28 V DC)
• Emergency Network

Question 2

What generates A/C Power?

Answer 2

4 Engine GEN
2 APU GEN (A &B)
4 External

Question 3

What is the minimum amount of engine generators required to supply all the AC bus bars?

Answer 3

At least two engine generators are necessary to supply all the buses.

Question 4

How is the AC ESS supplied normally and abnormally?

Answer 4

ACC ESS via AC Bus 1.
If AC Bus one fails, AC Bus 4 can supply the AC ESS bus via the AC ESS FEED pb set in ALTN mode

Question 5

What is the main difference between APU and engine AC generators?

Answer 5

APU is constant frequency whilst ENG Generators are varaible frequency

Question 6

Are APU and engine generators interchangeable in the network

Answer 6

below 22500, any APU Gen can replace an engine generator

Both APU Generators can supply the entire A/C electric network on the ground

Question 7

What is the minimum EXT ground power required for to supply the A/C?

Answer 7

2 external GPU’s.

2 and 3 Preferably

Question 8

What controls and monitors GPU’s, Engine, APU Generators?

Answer 8

A total of 6 GGPCU

GGPCU can control a generator and gpu simultaneously

Generator and Ground Power Control Unit

Question 9

What are the DC system components?

Answer 9

TRU 1 & 2
ESS TRU
2 BAT
ESS BATT
APU BAT

Question 10

Card showing ELEC architecture

Answer 10

Question 11

How is the emergency network powered before the RAT is deployed?

When AC 1, AC 2, AC 3 and AC 4 buses are lost in flight

Answer 11

• ESS Battery Supplies DC ESS which in turn supplies AC EMER via a Static Inverter (whilst the RAT deploys) as shown in the photo

It is segregated from the normal network

Question 12

How is the emergency network powered after the RAT is deployed?

Answer 12

• RAT the deploys and powers the AC EMER and AC ESS which uses the ESS TRU to power the DC ESS

Question 13

Card showing electrical distribution of the bus bars

Answer 13

Question 14

What is the role of the Electrical Network Management Units (ENMU 1 and ENMU 2

Answer 14

• Connecting/disconnecting AC and DC power sources
• Reconfiguring the electrical network, and
• Sending applicable information to the ECAM.

Question 15

Describe the role of the Electrical Load Management Unit (ELMU)

Answer 15

It automatically performs load shedding on AC commercial loads, in order to ensure the optimum use of the power sources

if it fails the ENMU can takeover to help shed large AC commercial loads