Electrical System

Question 1

AC Electrical Power

Answer 1

Provided by 5KVA alternator on each engine for windshield anti ice and fog protection.

Question 2

Main Batteries

Answer 2

Located in tailcone (Upper- Left/Lower-Right)
24volt
27/28 amp/hr = 30 minutes duration
38 amp/hr = 50 minutes duration
On the ground - Low voltage protection at 14v (inhibited during engine start)
Battery starts can be made above 0* C

Question 3

Emergency Battery

Answer 3

24v - lead acid
Located in nose
1 hr duration
Only used when not powered by GPU/APU/GEN
White EMER illuminates when the EMER Batt is discharging
Ground protection cutoff at 14v
Delay application of power to EMER Batt during initialization due to BITs

Question 4

Engine Generators

Answer 4

Starter/Generator
28vdc
300 amps
Auto online when deec determines engines are at 95% of N1 idle
Will not operate with GPU selected
Cooled by scoop or fan on ground

Question 5

GCU (Generator Control Units)

Answer 5

Regulate generator volage to 28vdc

Will auto disconnect if malfunction occurs

Question 6

GPU

Answer 6

1500 amps
24-32volts - regulated to 28volts
White EXTERNAL POWER CAS - cable connected w/5v
AVAIL light int he EXT PWR S/I GPU on and within acceptable parameters

Question 7

Isolation Contactors (Connect EMER Batt to Ess Busses)

Answer 7

Right contactor charges emer battery, L and R isolation contactors automatically close during flight to power ess busses from the EMER BATT

Question 8

Essential Contactors

Answer 8

Close to provide power from the GEN bus to the Ess buses. Auto open during engine start.