Electrical Flashcards
Name some important items on the MAIN HOT BATT BUS.
1 Fuel spar valves
2 Engine, APU & lower cargo fire extinguishers
3 Fire override switches
(Dark Aircraft) When the BATTERY switch selected ON which busses are powered?
MAIN & APU hot battery busses
MAIN & APU battery busses
After the BATTERY switch has been selected ON, selecting the STANDBY POWER switch to AUTO powers which busses and how?
The MAIN STBY bus and APU STBY bus are powered by their respective battery bus and invertors.
What items are powered by the APU STBY bus?
Left FMC, ND & PFD
What items are powered by the MAIN STBY bus?
Primary EICAS
Left EIU, CDU, ILS, VOR & VHF
With the loss of all generators which systems are inoperative?
LE flaps, anti-skid, reversers, auto-speedbrakes
How is the MAIN STBY bus powered in normal operations?
AC BUS 3.
How is the APU STBY bus powered during normal operations?
CAPT XFER BUS.
What is the source of power to the MAIN & APU BATTERY CHARGERS?
GROUND SERVICES BUS.
In flight how is the GROUND SERVICES BUS powered?
by AC BUS 1
What is the purpose of the GROUND SERVICES switch located next to the L1 door?
When AC BUS 1 is not powered, selecting the GROUND SERVICES switch ON powers the GROUND SERVICES BUS from the samr source as the GROUND HANDLING BUS.
What is the CAPT XFER BUS normal and backup power source?
Normally powered by AC BUS 3. If AC BUS 3 is unpowered, AC BUS 1 powers the CAPT XFER BUS.
What is the FO XFER BUS normal and backup power source?
Normally powered by AC BUS 2. If AC BUS 1 is unpowered, AC BUS 1 powers the FO XFER BUS.
When is the GROUND HANDLING BUS powered?
On the ground anytime EXT PWR 1 or APU GEN 1 is AVAIL or ON.
Name some of the items powered by the GROUND HANDLING BUS.
1 Lower cargo handling and lights
2 Fueling system
AUX HYDR DEMAND PUMP 4