Electrical Flashcards
What are the Main AC electrical power sources on the LCF aircraft?
Four IDGs
Two external power sources
What is the function of the Standby Power Switch in the Auto position?
Allows the main and APU standby busses to be powered from available sources.
What does the “AVAIL” light indicated on the external and APU power switches?
The related power source is plugged in and available, and the power quality is acceptable.
When is the main cargo deck handling bus powered?
When the “AVAIL” light is displayed on the APU 2 or EXT 2 switches.
What electrical power source provides power for the lower lobe cargo handling, fueling panel, and AUX 4 hydraulic pump.
EXT PWR 1 or APU GEN 1 is AVAIL or selected ON (powering the ground handling bus)
What are some of the items powered by the utility busses?
5 fuel pumps
Galley equipment
What happens when you pus a Generator Drive Disconnect (DRIVE DISC) switch?
- disconnects IDG from engine when above idle speed
- opens the related Generator Control Breaker (GCB)
What condition would automatically disconnect the IDG if not manually disconnected y the flight crew?
Excessively high drive oil temperature
What does a Bus Isolation (ISLN) light illuminated indicate?
- Bus Tie Breaker (BTB) OPEN
- AC bus isolated from the syncrhonous bus
How do you reconnect an IDG that has been disconnected?
IDG cannot be restored by flight crew action
- maintenance action is required
How is the electrical system configured during an automatic ILS approach (autoland)?
- AC and DC busses 1,2, and 3, are isolated form the synchronous bus
-AC bus 4 continues to power the synchronous bus
What are the main AC electrical power sources?
4 IDGs
2 APU sources
2 EXT PWR sources
