Electrical Flashcards
P6 panel location? How many
On right sidewall behind FO
4 panels
P7 panel location?
Aft of the overhead panel
AC system powered by? AC pwr with engines running?
2 APU generators and/ or 2 ext pwr receptacles.
4 IDG’s
How are AC buses powered while on the ground?
By ext pwr and APU generators through the synchronous bus
Cannot be paralleled
“AVAIL” lights indicate
Voltage and frequency of the respective pwr source are within limits
IDG’s lubricated and cooled by……
Self-contained oil system
Each IDG has a gen control sw and gen drive disconnect sw
T or F?
True
ELEC DRIVE 3 ( or 1,2,3,4)
Either low oil psi, or high oil temp, or GCB open due to uncorrectable gen freq fault in respective IDG.
Purpose of Synchronous bus?
Interconnects the 4 AC busses and allows the 4 IDG’s to work in parallel.
Split system breaker (ssb)
Separates synchronous bus into left and right half and allows each half to be powered by different APU or external power sources.
Ground handling bus powers?
Fueling sys Lower cargo handling equipment Lower cargo compartment lights Aux hyd pump 4 Flight deck access lights
Ground service bus powered when?
Powered by AC bus 1 on the gnd and in flight
Gnd handling bus can be powered on Flt and gnd?
False, gnd only
Gnd handling bus powers….
Lwr cargo handling equipment
Lower cargo doors
Aux hyd pump 4
Lwr cargo compartment lights
Fuel equipment
Gnd handling bus automatically when?
Ext pwr one is AVAIL
If not available, APU GEN 1 will power if AVAIL
Gnd service bus powers…
Both battery charger Cabin and service lighting Main tank 2 & 3 aft fuel pumps NAV lights Service outlets
Gnd service bus powered by?
AC bus 1
May be powered by EXT PWR 1 if available by pushing “gnd svc” switch at L1 door.
Main deck cgo handling bus powered when?
On gnd only!
When is MDCH bus powered?
Automatically when EXT PWR 2 or APU GEN 2 is AVAIL
Ext 2 has priority if both are available
Must all P7 cb’s be in for normal operation?
Yes
2 P7 panel
How many P6 panels?
4
What is powered on the gnd svc bus? Service the clam!
Clam
Chargers
Lights
APU fuel pump
Misc equipment
What is powered by the gnd handling bus?
Hold the handle so you don’t FALL
Fueling panel
Aux hyd pump
Lights
Lower cgo handle
Utility buses power:
fuel boost pumps (2)
fuel override/jettison pumps (3)
crew rest lighting selected a/c components lav equipment galley power misc equipment electrical outlets
ELCU?
utility busses connected to ac bus via ELCU.
monitors load and power
provides load shedding capability
Can bus ties be reset? how about gcs?
yes, press once for off. then again for reset. if fault is cleared, it will reset.
