757 Systems - Electrical

Question 1

What does the GEN CONT OFF light indicate?

Answer 1

The associated breaker is open.

Question 2

What does the APU GEN OFF light indicate?

Answer 2

There is a fault or the switch was turned off.

Question 3

What does the GEN CONT ON light indicate?

Answer 3

1. The breaker is armed for automatic operation (when associated with the OFF light)
2. The breaker is closed (IDG is powering main bus)

Question 4

What is the primary purpose of the Bus Tie Breakers?

Answer 4

To keep the main buses powered

Question 5

What is the priority order for automatic powering of the main buses?

Answer 5

1. Associated IDG
2. APU generator
3. Opposite IDG

(External power is only selected manually)

Question 6

What does the BUS TIE ISLN light indicate?

Answer 6

The associated bus tie breaker was manually selected open

Question 7

If an overload condition occurs, what is the load shedding order?

Answer 7

1. All galleys

2. Left and right utility busses

Question 8

What buses are powered by the Battery/Standby Power system?

Answer 8

1. Hot Bat bus
2. Bat bus
3. Standby DC bus
4. Standby AC bus

Question 9

What are the normal and approach mode power sources for the various autopilots?

Answer 9

Normal
Left main bus - left and center AP
Right main bus - right AP

Approach
Left main - left AP
Right main - right AP
Battery/Standby- center AP

Question 10

How long does the battery provide power if all other power sources fail?

Answer 10

30 mins

Question 11

What does the STANDY BUS OFF light indicate?

Answer 11

Either or both the standby AC bus and standby DC bus are unpowered.