Oral Study Guide Overhead Panel

Question 1

Where does the DC service switch get power from?

Answer 1

AC battery direct bus

Question 2

Why do we not leave the airplane in the service configuration using the DC service switch?

Answer 2

Drains APU battery

Question 3

With the battery master (DC power) on (no AC power established) which screens come online? What is the limitation?

Answer 3

5 mins because fans are AC powered

Question 4

What does the AVAIL illumination on the AC switchlight indicate?

Answer 4

External power available: correct voltage, frequency, phase

Question 5

What does the FAULT illumination on the IDG switchlight indicate?

Answer 5

High oil temp, low oil pressure

Question 6

What does the DISC illumination on the IDG switchlight indicate?

Answer 6

IDG is disconnected

Question 7

How can an IDG be disconnected?

Answer 7

Manually: press DISC switchlight
Automatically: if solenoid is melted or shaft is sheared, no indication on EICAS but FAULT would be illuminated on switchlight