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CRJ-900 Limitations > Electrical > Flashcards

Flashcards in Electrical Deck (31):
1

Location APU battery

Aft equipment bay

2

Max engine generator load

40 KVA

3

Max APU generator load

40 KVA

4

Max transformer rectifier unit (TRU) load

120 amps

5

Max permissible time for ground operations with battery power only

5 min

6

What is the reason for the previous limitation

To prevent ED1 and ED2 from overheating (fan are AC powered)

7

How many TRUs are installed in the CRJ 900

4

8

Where are the TRUs located

Nose compartment

9

The main battery is rated to

17 ampere hour / 24 volts

10

APU battery is rated to

43 ampere hour / 24 volts

11

How many generators are installed

4, 2 engine generators, 1 APU generator, 1 ADG

12

What is the function of the 4 TRUs

To covert 115v AC to 28 v DC power

13

How are the TRUs cooled

Individual fans

14

Which buses are powered when the battery master switch is selected on

Main battery direct bus, APU battery direct bus, DC battery bus

15

If the main buses are powered, are the essential buses automatically powered

Yes

16

What controls the DC tie contractors

The DC power centers (DCPC) automatically control DC tie operation

17

Is there an on/off switch for the TRUs

No, they are automatically powered when the AC busses are powered

18

When will the air driven generator (ADG) automatically deploy

With complete loss of AC power

19

With the ADG deployed, what are the basic items that are powered

AC ESS Bus, Hydraulic pump 3B, flaps/slats, STAB trim CH2

20

What is the ADG max load

15 KVA

21

Location of main battery

Nose compartment

22

Main electrical power for the CRJ

115 Volt AC power (primary)

23

Secondary electrical power for the CRJ

28 Volt DC power (secondary)

24

How many circuit breaker panels are there in the CRJ

4 total

2 circuit breaker panels in the flight deck
1 aft equipment bay
1 forward nose compartment

25

GCU (generator control unit) controls what

Controls and monitors the generators and provides protection and voltage regulation for each generator

- over/under voltage
- over/under frequency
- generator or BUS over current
- generator phase sequence

26

IDG does what with N2 variable speed

It coverts the variable N2 engine speed to a constant 12,000 RPM generator speed

27

IDG FAULT switch/light indicates

High oil temperature or low oil pressure within the IDG

28

DISC of The IDG switch/light indicates

IDG has automatically disconnect by Shearing without disconnecting it manually

29

How many AC generators must you have to support the plane

1 AC generator can support the whole plane

30

Battery chargers get power from where

Main battery charger gets its power from AC BUS 1
APU battery charger gets its power from AC Service BUS

31

DC Emergency BUS powered by

APU battery direct BUS (considered hot BUS)