Chapter 6 - Electrical Flashcards
What do the APU GEN and GEN CONT switches do ?
They ARM to close the breaker when power is available.
When do the APU GEN and GEN CONT OFF light illuminate ?
Whenever the breaker is open (because power is not available).
What does the BUS TIE switch do ?
It arms:
- The AC bus tie
- The DC bus tie
- The respective flight instrument transfer bus
When does the bus tie ISLN light illuminate ?
When the AC bus tie breaker is open.
Not in case of the DC bus tie.
How can the load shed circuitry be reset ?
By recycling the UTILITY BUS switch.
When does the generator DRIVE light illuminate ?
When the oil pressure is low OR oil temperature is high.
Can a generator disconnect be reset in-flight ?
No.
When does the standby power OFF light illuminates ?
When the AC or DC standby bus or the battery bus is not powered.
When does the battery OFF light illuminate ?
When the battery switch is off.
Can one AC source power the whole electrical load ?
No. Two sources are required for the full load.
If APU is running and external power is connected, is the APU powering the main busses ?
No.
What is priority of AC power sources ?
- Ground power
- IDG
- APU
- Opposite IDG
Are there any indications or EICAS messages for a galley bus which is not powered.
No. Only when the utility bus is not powered as well.
Which bus powers the GND SVC bus ?
R MAIN AC BUS.
How is the GND HANDLING bus powered ?
From the APU GEN or from external power.
