Crj Electrical Flashcards
What is the primary source of ac power.
Ac powered delivered by the idg. (Integrated drive generators)
What power does the crj use
115 vac and 28 v dc
How is ac converted to dc
Through 5 tru located in nose
What are sources of dc power.
Converted power from tru.
Two dc batteries in aft store dc power for emergency and normal ops.
How many cbs are there
5
4 up front 1 in aft
What power do the idg supply
115 vac 400 he 3 phase
What does the idg consist of
The constant speed drive csd
(Maintains constant rpm for consistent generator electric output)
The generator
How is the oil in the idg cooled.
Bypass air from n1
What does thd fault light on the idg indicate?
Acts as an oil light for idg. Overheat or pressure.
When will idg disconnect automatically?
Over temp or over torque
What conditions will cause a generator to be tripped off line.
What unit controls that?
Over/ under voltages
Over/ under frequency
Generator or bus over current
Gcu (generator control unit)
For external ac power to be accepted what is checked?
Voltage, phase and frequency
What is the power priority for bus 1 and bus 2
On side gen
Apu
X side gen
External power
What does thd ac ess transfer button do?
Manually transfers power to the ess bus from bus 1 to bus 2
What happens when ac power is lost.
Adg deployes and connects to the essential bus.
How do we get power back to the ess bus from bus 1 after power has been restored?
By pressuring the per txfr override button on lower pedestal.
What do the utility buses provide power to?
Galley and battery chargers
When are utility buses auto shed?
During flight when a gen fails. Load shedding.
On ground…single gen, flaps not up and pax and service doors closed.
What does the adg power?
Ac ess bus and acmp 3b pump
What is required for adg auto deploy?
Bus 1and 2 not powered and all 3 gens inoperative.
How many dc buses are there?
10
What are the dc batteries for?
Emergency power and apu starting on ground.
What is the amperage of each tru?
100 amps
What are thd five trus?
Tru1 Tru1 Tru1 ess Tru2 ess Serv tru
Which dc tie contractors can be manually selected? which ones are auto?
All can be manually selected.
Only tie 1 and 2 are auto
When are dc utility buses load shed.
When associated tru is not powered.
What are the power outputs of both batteries.
Main 24vdc at 17 amperes
Apu 24vdc at 43 amperes
What dc buses do the batteries supply power to
Main batt bus
Apu batt dir bus
Dc emer bus
Dc batt bus
What does the dc emer bus provide power to?
Apu fire extinguishers
Fuel and hydraulic shutoff valves
The dc emer bus is connected to the batteries via what buses?
Apu dir batt bus and the batt bus and is continuously powered .
How long can the batteries supply emer power for?
30 minutes
Will you lose emer power upon touchdown?
Yes wow removes power from the dc ess bus unless the adg handle us pulled to make that connection
