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75 Cards in this Set

  • Front
  • Back
How many networks make up the electrical system on the airplane
2 independent networks for reduncancy
What happens if a power generating source fails
Bus ties automatically connect to provide no system degradation
What components power the AC system
2 IDG's
1 Inverter
1 RAM air turbine
1 AC GPU receptacle
What components power the DC system
2 Nicad batteries
1 DC GPU receptacle
How does the IDG maintain a stable power output
A constant speed drive attaches the IDG to the accessory gearbox
What monitors and controls the IDG's
Can one IDG supply the entire electrical system
What will cause the amber light on the electrical panel to illuminate
IDG high oil temp and low oil pressure
If an IDG is manually disconnected can it be reconnected by the flight crew
No, MX only
What is the primary purpose of the AC generators
To power the AC Busses and AC ESS bus which powers the 3 TRU's
What is the purpose of the TRU's
To convert 115 VAC to 28 VDC
Can the APU replace a failed IDG
What is the AC electrical source priority
Onside (IDG)
Inside (APU)
Outside (GPU)
Crosside (Other IDG)
How is it known that the AC GPU is hooked up to the airplane and ready for electrical power
GPU button displays AVAIL and the GPU icon is displayed on the electrical synoptic page

Once the GPU button is pushed in, the button will display IN USE and the airplane is now AC powered
What does it mean if the AC GPU is plugged in and the outside GPU button displays in use
Ground service bus is in use

Cockpit GPU button will display AVAIL even though the ground service bus is in use
If the airplane is using the AC GPU and the APU is started what should the pilot be sure to do
Deselect the GPU button before the next GPU connection
What will charge the batteries
Any AC source
How long will the aircraft batteries last with no recharging
10 minutes
What is the purpose of the DC GPU receptacle
For APU start when battery volts are less than 22.5 or if battery temp is less than -20 C
What is the minimum battery temp for APU start
-20 C
What is the minimum battery voltage to close the battery bus ties
18 volts
What battery is used for APU start
Battery 2 powers the apu starter

Battery 1 powers the APU FADEC and EICAS for monitoring
What is the purpose of the inverter
Convert 28 VDC from the batteries to 115 VAC to power the AC STBY BUS when an AC source is not available
How many volts are the batteries
24 Volts
What is on the AC STBY BUS
Engine exciters 1A and 2A
What powers the RAT
Airflow turns the RAT propeller which spins the turbine inside
When will the RAT deploy
Loss of both AC busses or manual deploy by the pilot
How long after deployment before the RAT supplies power
8 seconds
What supplies power for the 8 seconds the RAT is spinning up
The batteries supply power to the DC ESS busses and AC STBY BUS
What does the RAT power
What is the minimum airspeed for the RAT
130 Knots
What happens to the RAT below 130 knots
Load shedding

Galley power and FO windhield heat
When is the RAT icon displayed on the electrical synoptic page
Only when deployed
What manages the electrical system
4 ICC's
2 SPDA's
How many busses are powered when only the batteries are turned on
What is an ICC
An electrical control device which provides power distribution and protection for electrical loads
What is an SPDA
An electrical load management unit powered by the ICC's that distributes electrical loads to aircraft systems according to distribution logic
Can the flight crew reset the ICC and SPDA remote electronic CB's
ICC's CB's can only be reset my MX on the ground

SPDA's CB's can be reset via the MCDU
How long must the DISC be held for to disconnect the IDG
1 second
Does BATT 1 supply power when it is off
Yes, to the HOT BUS
What is the power rating of the IDG's
40 KVA, 115 V, 400HZ, 3 Phase
What is the power output of the RAT
15 KVA, 115 V, 400HZ, 3 Phase
What does it mean if the battery digits turn red
Battery temp has reached 70 C for 2 seconds
When is external DC GPU power used
If connected during APU start, the DC GPU and not Battery #2, provides 28 VDC power to the APU start bus
What is the normal source of power for the AC STBY bus
AC ESS bus, unless unavailable then it is the inverter. (8 sec for rat)
How many sources of AC power are there
1 Inverter
Is there an altitude restriction for RAT deployment
What is the minimum speed for RAT usage
What powers the emergency lights
4 dedicated batteries
How long are the emergency lights good for
10 minutes
What charges the emergency lights
DC Bus 1
How do we turn on the DVDR
Through the MCDU
What indicates a good test on the DVDR
No EICAS messages
What can be erased on the CVR
Voice only
How much audio can be recorded on the DVDR
120 minutes
How much flight data can be recorded on the DVDR
25 hours
How many minutes of digital communication can be recorded on the DVDR
120 minutes
What is required to erase the CVR
Aircraft on ground and parking brake set
How many DVDRS on the aircraft
2, 1 aft and 1 forward
When does the CVR start and stop recording
As soon as power is supplied and removed
When does the flight data recorder start recording
Engine is turned on or aircraft in the air with no WOW
When does the flight data recorder stop recording
WOW and engines off
When are the aircraft generators available
50% N2
If the GPU is plugged in and selected by the flight crew what would happen if theAPU was started
The GPU switch would go back to saying AVAIL
What is powered during an electrical emergency prior to the RAT coming on line
DC ESS 1,2,3, AC STBY bus
During the 8 seconds the RAT is spinning up what message will be displayed on the EICAS
Battery Discharging
What hydraulic system is affected when the RAT is spinning up
Hydraulic system 3, pump 3a will reduce its flow and output to aid the RAT in spinning up and prevent it from stalling out
What busses are available once the RAT has spun up
What are the 6 amber lights that are shown during the EMRG LIGHTS test
2 BLEED leak
1 APU leak
1 Door INHIB
What instruments are powered during an electrical emergency
Captain will have PFD presented on #2 DU, EICAS, FO MCDU, Captain CCD, IESS, MAG compass
Explain why BATT 1 has an ON position and BATT 2 has an auto position
During APU start BATT 1 will supply power ro the APU FADEC and connect to DC ESS 2, BATT 2 will connect to the APU start BUS to provide power for the APU start
What does ICC stand for
Intergrated Control Center
How many ICC's do we have
1 left
1 right
1 emergency
1 auxillary
What is no longer powered by the RAT if speed is below 130
During an electrical emergency what two dedicated valves are used for hydraulic system 3
Pump unloader valve-Reduces discharge pressure for startup. It reduces pump torque which reduces electrical power required

Flow Limiter Valve-Reduces flow to limit electrical power & prevent the pump from possibly stalling the RAT