Electrical Flashcards
Electrical faults are automatically detected and ____ isolated.
Automatically ()
The main electrical power sources are:
4 IDGs, 2 APU Gen, 2 Ext Power
The ground service bus is powered whenever the ____bus is powered.
AC Bus 1 ()
The First Officer transfer bus is powered by_____.
AC Bus 2 or AC bus 1 () FCOM 6.20.4
During automatic ILS approaches AC and DC busses #1, #2, #3 remain connected to the synchronous bus for redundancy electrical backup to autopilots. True or False.
FALSE ()
Standby selector power selector switch in BAT will provide approximately ____minutes of emergency power
30 min ()
If AC bus 1 is unpowered (all engines operating) which of the following will be observed?
ELEC AC BUS 1 ()
When is the EICAS advisory message DRIVE DISC displayed?
IDG disconnect ()
AC bus 1, 2 and 3 isolation lights and EICAS advisory message ELEC BUS ISLN may be displayed during autoland. True or False.
False. ( AC BUS ISOL light1,2,3 remain extinguished. The EICAS msg ELEC BUS ISOL is not displayed. The msg “ELECTRICAL SYNOPTIC INHIBITED FOR AUTOLAND” is displayed on the electrical synoptic)
The ground handling bus supplies power to:
- cargo handling equipment and compartment light 2. fueling system 3.Aux hyd. pump #4
When the EICAS advisory message ELEC BUS ISLN is displayed:
BUS tie breaker open (BTB), effective bus is disconnected from synchronous bus,ISLN displayed on synoptic
The EICAS advisory message BATTERY OFF is displayed when the main battery is discharging.True or False.
False. It is displayed when battery switch is OFF ()
When is the EICAS advisory message BAT DISCH APU displayed?
APU battery discharging or during Standby power test ()
With both APU generators connected; after the #4 engine has been started, the respective IDG automatically powers its side of the synchronous bus.True or False.
TRUE ()
What occurs if available generator power is less than electrical system demand?
Load shedding. No EICAS msg or lights ()