ELECTRICAL

Question 1

L AC BUS OFF, any consideration?

Answer 1

AP engagement requires at least 2 FCC
L FCC powered by L AC/DC bus
C FCC powered by Center AC/DC bus
R FCC powered by Right AC/DC bus
in normal flight Center AC/DC bus is powered by L AC/DC bus

Question 2

Ground Handling bus power what? (4)

Answer 2

Cargo doors
Ground handling equipment
Cargo compartement lights
Refuelling panel

Question 3

When is the ground handling bus powered? by what?

Answer 3

ground handling bus only powered on ground

powered from APU or external power

Question 4

Ground service bus power what? (5)

Answer 4

main bat charger
APU bat charger
1 on the aft equipment cooling fan
L forward fuel pump
Miscellaneous cabin loads

Question 5

What normally power the ground service bus?

Answer 5

R AC BUS

Question 6

on ground, How can you connect the ground service bus?

Answer 6

on ground you can connect the ground service bus to external or APU by using the ground service switch (FA panel)

Question 7

What arms the load shed system to trip OFF both utility bus with a loss of a generator?

Answer 7

Aircraft inflight or

both thrust levers in the TO range on the ground

Question 8

What bus are powered on bat/standby power? (4)

Answer 8

HOT BAT BUS (clock, IRS emerg power)
BAT BUS (fire detection, pax Oxy deploymen
Standby DC BUS (L VHF, manual cabin alt)
standby AC BUS ( L air data computer)

Question 9

With the standby power selector positionned to BAT?

Answer 9

Standby busses powered from battery if BAT switch ON

Question 10

With the loss of a generator, the utility busses?

Answer 10

Can be reset in flight by re-establishing a second generator

on the ground, with one or both thrust levers retarded they can be reset

Question 11

Generator loss load shedding is armed when? (2)

Answer 11

requires that air/ground logic is in flight mode
or
the thrust levers are moved into the TO range
advancing both thrust levers on the ground, even with both engines shut down, can cause a trip off of utility and galley buses

Question 12

With 1 eng operating, powering L and R systems, when APU gen becomes available?

Answer 12

The operating generator BTB opens but does not trip off

Question 13

the position of an AC bus tie switch controls?

Answer 13

Both AC and DC but tie closure systems

Question 14

What is the priority for the AC bus power?

Answer 14

respective engine driven gen, APU gen, opposite engine driven gen

Question 15

the DC bus tie breaker is automatically controlled by?

Answer 15

the AC Bus Tie switches

Question 16

During engine start with external power connected, what happen when the L eng is started?

Answer 16

the ground power trips off

Question 17

When the center buses are isolated during an automatic approach?

Answer 17

they are powered by the hot battery bus and standby inverter

Question 18

If the galley buses trip off due to overload load shedding?

Answer 18

Galley buses automatically reset during engine start

Question 19

With L BTB OFF, R BTB AUTO and R main AC bus lost, what happen to the flight instruments?

Answer 19

Both CA and FO flight instruments remain powered