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31 Cards in this Set

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4 sources of AC power?
2 engine driven generators, AC external, APU generator
GRD POWER AVAILABLE blue light means?
External power is available (no info on quality). Stays on while in use. External AC bus is powered.
BPP is?
Bus Protection Panel. Tastes external power for you and allows both Ground Power Relays (GPR) to close if it's good.
Ground Service Switch. Where is it, what does it power, and where does it get power from?
FWD FA panel. Connects external power directly to ground service bus only (utility outlets, battery charger, cabin lighting). Electromagnetically held in on, auto off if EXT PWR lost or generator bus 1 is powered.
Generator and Main Busses provide power for what kind of systems?
non essential items (galley power and cabin lighting) and high-load items (electric hyd pumps and window heat)
Transfer busses power?
Main instrument controls, displays, and some essential items (eg, EHSI, EADI, FMC, CDUs, engine ignition, anti smash lts)
What is shed during single generator ops?
Galley Power
Battery charger normal power source? Transfer power source?
Generator bus 1 transfers to main bus 2
T/R 1 powered by:
T/R 2:
T/R 3: (supplies DC power to the battery bus):
Transfer Bus 1
Transfer Bus 2
Main Bus 2
what happens in the event of a TR failure
Other two take over, except in case of TR 3. In this case battery bus goes to the hot battery bus.
Purpose of the battery
APU start and emergency power for essential equipment.
Loss of both generators, battery supplies power to:
-Hot Battery Bus -Switched Hot Battery Bus -Battery Bus -AC standby bus -DC standby bus
When will an automatic transfer of both standby busses occur?
STANDBY POWER switch is in AUTO, the airplane is airborne, and EITHER transfer bus 1 OR DC bus 1 loses power.
Manually positioning the STANDBY POWER switch to BAT does what?
AC standby bus, DC standby bus and battery bus switch from primary power source to secondary power source.
Primary and secondary power sources for AC standby bus, DC standby bus, and battery bus?
AC: transfer bus 1; battery bus thru static inverter

DC: DC bus 1; battery bus

Battery bus: TR3; hot battery bus
STANDBY POWER to OFF does what?
Disconnects power from AC and DC standby busses, regardless of primary power source availability. Does not affect Battery Bus.
When does amber STANDBY PWR OFF light illuminate?
When AC standby bus is not powered (light doesn't monitor DC standby bus).
STANDBY POWER switch does not affect which bus?
Switched Hot Battery Bus
Two sources for battery charger?
Primary: GND service bus via generator bus 1 Secondary: Main bus 2 via generator bus 2
What will happen if you push RESID VOLTS button with generator control breaker and generator field relay closed?
The airplane blows up. No, not really. But you can damage AC voltmeter.
GFC open what indications show on CPS FREQ meter and AC VOLTS meter?
Needles pegged to left. Can check residual voltage in this configuration.
BAT switch ON and OFF?
ON: switched hot battery bus powered by the battery charger, the battery, or DC ext. Battery bus powered by TR3 or hot battery bus OFF: removes DC power from switched hot battery bus and battery bus.
BAT switch OFF and STANDBY POWER switch to BAT?
Battery bus gets power from hot battery bus, but switched hot battery bus remains unpowered.
When do flourescent background lights illuminated at a fixed intensity?
Loss of transfer bus 1 (now powered by AC standby bus)
What lights are NOT tested by Master lights switch?
marker beacon, autoflight annunciator (A/P, A/T, FMC), parking brake and (on some airplanes) master fire warning lights
Will the AC Transfer Relays transfer automatically?
Which switch controls this?
illuminates when gear is down or TEF not up...
Can auto xfer of AC power occur if the BUS TRANSFER SW is off?
When does the DC Disconnect Relay open? (2)
1. The Bus Transfer sw is off.
2. Glide Slope capture with min of one FD or AP on.
Does the taxi light extinguish automatically when the gear is raised?
How do you turn on the map light?
Pull the knob out.