Electrical

Question 1

What are the sources of airplane generated AC power?

Answer 1

Two 115VAC, 60kVA engine driven variable frequency generators (67.5kVA for 5 minutes, 75kVA
for 2minutes and 90kVA for 5 seconds)

One 115VAC, 60kVA APU generator (67.5kVA for 5 minutes, 75kVA for 2 minutes and 90kVA for
5 seconds)

One 115VAC, 9kVA Ram air turbine when all other AC sources have been lost (13.5kVA for 5
minutes, 18kVA for 5 seconds)

Question 2

In the event of single generator operation, which AC Buses are automatically shed?

Answer 2

None; a single generator supplies power to all three AC buses (although, some high load users,
such as certain hydraulic system pumps, are load shed)

Question 3

What does an EXT AC “AVAIL” annunciator on the ELECTRICAL panel indicate?

Answer 3

External AC power is connected
Power is the correct voltage and frequency
External Power is not on line

Question 4

Where is the location of the external ground power panel? (FCOM2, Doors)

Answer 4

Lower body fairing below the right engine

Question 5

Which buses are powered with EXT AC connected, on and in “normal mode”?

Answer 5

All AC and DC buses are powered

Question 6

What is the AC priority source for AC BUS 1 and 2?

Answer 6

Onside engine VFG
APU Generator
External AC Power
Opposite side engine VFG

Question 7

What is the voltage and ampere-hours rating of the batteries?

Answer 7

24VDC, 28Ah

Question 8

What is the minimum battery voltage for start?

Answer 8

22VDC

Question 9

Where are The APU and Main Batteries located?

Answer 9

APU battery is in the belly fairing compartment below the baggage bay door
Main battery is in forward equipment bay in the nose of the airplane

Question 10

How long will the aircraft main batteries last as the sole source of power?

Answer 10

Minimum of 5 minutes

Question 11

How do you know when a battery is not being charged?

Answer 11

A Cyan DISCHARGING indication on top of the battery on the ELEC synoptic page
A cyan BATT DISCHARGING CAS message
If the ELECT synoptic page shows 24VDC or less and decreasing, it is not being charged

Question 12

Which DC Buses are automatically shed during a single TRU Fail?

Answer 12

None; all remain powered

Question 13

Which DC Buses are automatically shed during a TRU 1 and 2 Fail?

Answer 13

DC BUS 1 and 2

Question 14

Can a thermal circuit breaker be reset from the Electronic Circuit Breaker Application (ECB)?

Answer 14

No, the affected circuit breaker can only be manually reset at its location

Question 15

Will a physical CB trip generate a CAS message?

Answer 15

Yes, a cyan CB TRIP CAS message

Question 16

How do you determine the location of an open CB?

Answer 16

Viewing the location on the CB application

Question 17

When does the RAT automatically deploy?

Answer 17

In the event of a complete loss of AC power in flight

Question 18

How can the RAT be stowed?

Answer 18

On the ground only by maintenance

Question 19

If the RAT Generator trips offline, how can it be reset?

Answer 19

By moving the RAT deployment handle to stow and back to deploy position

Question 20

When does the RAT generator go off line?

Answer 20

Below 147kt
Note: Slat-Flap, Pitch Trim, Left window heat, ESS TRU disconnected, and reversion to direct
mode may occur. Then at 102kts hydraulic pressure is lost

Question 21

If a generator is reset after the RAT has deployed, which buses will the RAT power?

Answer 21

AC ESS Bus