Electrical Flashcards
What is the normal electrical supply for AC EMER BUS?
AC ESS BUS
How is an IDG disconnect confirmed?
The IDG FAULT light extinguishes and Gen FAULT light
illuminates
The IDG is disconnected while airborne, when can the IDG be reconnected?
Only by a mechanic when on the ground
In the A300 electrical system, what are the 4 AC buses?
AC EMER, AC ESS, and AC #1 & #2
What is the normal electrical supply for AC ESS BUS?
AC bus #1
What happens when both AC OVRD Supply switches are
selected ON?
AC EMER, AC ESS, and DC ESS are the only busses supplied
If the AC ESS BUS is lost, how may the AC EMER BUS be
supplied?
DC ESS BUS via automatic activation of the Emergency Static
Inverter
In the A300 electrical system, what are the three DC Buses?
HOT Battery Bus, DC ESS, and DC NORM
Which switch will manually connect the batteries to the DC
ESS bus?
BAT OVRD
What is lost with the BAT OVRD switch selected ON?
STBY GEN operation, BAT overheat protection, BAT charging
Avionics smoke drill is equivalent to standby generator in that
they both have three buses that are de-energized. What three
busses are they?
AC Bus 1 & 2 and DC Norma
How does selecting the LAND RECOVERY switch ON affect the
STBY GEN operation?
It disconnects the DC ESS BUS from the STBY GEN and uses the
batteries to power the DC ESS BUS
Which system is not recovered with the LAND RECOVERY
switch selected ON?
Kruger Flaps
Selecting the MECH CALL HORN CTL switch (on the overhead
panel) to ON does what?
It deactivates the nose gear mechanic call horn for battery
discharge on an unpowered aircraft
If OVRD SUPPLY #1 is supplying AC ESS BUS, and the #1 IDG
fails, how is power restored to the AC ESS BUS?
Deselect OVRD SUPPLY #1 then Select OVRD SUPPLY #2 ON
During an electrical emergency, what items are recovered
when the LAND RECOVERY switch is selected ON:
1 slat motor, 1 flap motor, spolier/speedbrake/ground spoiler
panels 2,3,5,7, Normal Brakes, Normal Anti-Skid
In normal operation, what powers AC BUS 2?
GEN 2
If AC ESS BUS is lost due to a fault on the AC BUS #1, how is
power restored to the AC ESS BUS?
Select OVRD SUPPLY 1 switch to ON
During STBY GEN operation, if an APU start is unsuccessful,
why is it important to place the APU Master switch back to the
OFF position?
To re-connect the DC Standby generator and disconnect the 3
batteries from the DC Ess Bus
How can the crew confirm that the standby generator is
operating and supplying power to the electrical system?
The Blue AC EMER ON INV light and the Amber DC ESS ON BAT
lights are extinguished and Fuel Crossfeed valve is in-line
The aircraft is in-flight, the #1 engine has failed, and the APU
is not operating, how will the electrical system be configured?
GEN 2 automatically powers AC BUS 1
What will the Battery Charge Controller (BCC) do if BAT 1
overheats?
Automatically disconnect BAT 1
A Fault is detected on AC BUS 1 and it is disconnected, which
switch will connect GEN 2 to the AC ESS BUS directly?
OVRD SUPPLY 2
The APU is operating and EXT PWR is connected and selected
ON. In this configuration, what is supplying the electrical
system?
EXT PWR, it has priority over the APU GEN
What is the NORMAL supply for DC ESS BUS?
DC NORM BUS via DC BUS TIE and the ESS TR
Which electrical busses does the Standby Gen supply?
DC ESS bus, AC ESS #2 bus, AC EMER bus
If the aircraft batteries are the only source of electrical power,
what busses will they supply?
DC ESS BUS and AC EMER BUS
With the Standby Generator running, what happens if the BAT
OVRD is selected ON?
Standby Gen quits supplying the emergency electrical system
When does the Battery Charge Controller (BCC) not connect
the batteries to the DC ESS BUS?
DC ESS BUS supplied by Standby Gen
If all electrical power sources are available, what is the auto
switching priority of the AC electrical system?
Onside Gen, Ext power, APU, Other Gen
In the electrical system the green flow bars on the battery tiles
are an indication that the battery tiles are in what state?
Connected to the DC ESS bus
In the electrical system, what items are not on the HOT
battery BUS?
Eng and Cargo Fire detection systems
What is the DC NORMAL Bus powered by?
TR 1 & 2
When powering up an unpowered aircraft, what is indicated if
the blue AC EMER ON INV light does not illuminate when the
batteries are switched on?
A fault with the Inverter
Illumination of the AC BUS 1 OFF, AC ESS BUS, and AC EMER
ON INV lights while inflight indicates that this component has
failed.
AC BUS #1
Both generators fail in-flight. The standby generator fails to
automatically start. Which switch can manually start the
standby generator?
STBY GEN
