CRJ 700/900 Electrical Flashcards
The main aircraft generators supply power to how many AC buses:
4
What is the APU generator rated at?
115-volt AC, 400-Hz, 40 KVA up to 41,000 feet.
What is the 28VDC supplied by:
Transformer Rectifier Units (TRU)
The APU battery is:
24 volts DC, 43 ampere hour
The main battery is:
24 volts DC, 17 ampere hour
How many transformer Rectifier units supply DC buses
4
Cranking power for the APU is supplied by:
APU Battery
The main and APU batteries are kept in charge condition by battery chargers powered by:
Main battery charged by: AC BUS No.1
APU Battery charged by: AC Service BUS
The external AC power receptacle is located?
Forward right side of airplane
The Electrical system warnings and caution messages are normally displayed on the:
EICAS Primary page
Electrical system status and advisory messages are normally displayed on:
EICAS status page
The Integrated Drive Generator (IDG) provides a means do converting:
Variable engine speed to constant generator speed
The IDG may be disconnected from the gearbox by
Disconnect switches located in the cockpit
Once the IDG is disconnected it can be reconnected by
By maintenance on the ground with engine shut down
The IDG converts variable engine speed to what constant RPM
12,000 RPM
Fault protection for each generator is provided by
Generator control unit (GCU)
The power priority for allowing power to AC Bus 1 would be
Gen 1, APU, Gen 2, External AC
same side, inside, cross side outside
IDG 2 normally powers
AC bus 2
Service bus
115 VAC is supplied to the TRUs for DC static conversion and each TRU is rated at ___ amps
120 amps
An ESS TRU failure message will be displayed on EICAS when
Output is less than 18 VDC
In flight, the ADG auto deploy monitors the three main AC generators and the main AC buses for
Complete power failure
When are the main and APU batteries charging
Battery master switch ON and AC bus 1 powered
Battery master switch ON and AC Service Bus powered
Main batt and APU batt “OFF” caution message are displayed on EICAS when voltage is at or below
18 VDC
An amber IDG fault light/caution light indicates
Low IDG oil pressure and/or high oil temp
A Gen 1 overload caution messages on EICAS would indicate a load greater than
40 KVA
An AUTO XFER fail light (amber) on the electrical panel indicates
GCU had detected a fault and taken associated Generator offline.
An AC ESS XFER light (white) on the electrical panel indicates
AC ESS bus is not being powered by AC bus 1
What are the generators rated at
40 KVA up to FL410
Batteries supply DC electrical power to which buses
Main batt direct bus
APU batt direct bus
DC EMER bus
How many circuit breaker panels are there and where are they located?
Four total. Two located in the flight compartment, one in the aft equipment bay and one in the forward unpressurized nose compartment.
How many batteries store and provide a source of DC electrical power for normal and emergency operations?
Two nickel cadmium (nicad) batteries, one located in the aft equipment bay and one in the forward unpressurized nose compartment.
How many AC generators are on the CRJ?
- Two engine driven integrated drive generators which provide AC power to the ACPC for normal operations and the APU generator for backup.
Generator KVA Overload protection occurs at:
45 KVA for 5 minutes
60 KVA for 5 seconds
Bus priority for AC Bus 1:
Gen 1
APU Generator
Gen 2
External Power
Bus priority for AC Bus 2:
Gen 2
APU Generator
Gen 1
External Power
The aircraft engine driven and APU generators are rated at?
40 KVA
Which DC Bus ties have automatic protection
Main tie
Cross tie
ESS tie
When the ADG supplies power to AC ESS Bus, where does the power also flow to?
From the AC ESS Bus, power moves to the ESS TRU 1 which powers DC ESS Bus and DC Battery buses.
The ADG only supplies power to: (4 things)
AC ESS Bus
Hydraulic 3B pump
Slats/Flaps
Pitch trim.
The ADG supplies AC power to:
3B hydraulic pump, ESS AC Bus, slats/flaps and pitch trim
Items on the DC Emergency Bus ?
- SOVs - hydraulic, fuel, bleed air
- FIREX Squib
- Refuel/Defuel panel and valves.
ADG, IDGs, and APU Generator are all how many Volts ?
115 volts AC