Electrical System

Question 1

Overview

Answer 1

Split bus 28V DC power system
Bus 1 powers downstream
Bus 2 load sharing & backup for critical systems

Question 2

Power Conversion

Answer 2

115V AC is converted to 28V DC from the AC Power Module (ACPM) to the DC Power Supply (DCPS)

Question 3

Four Power Suppy Sources

Answer 3

Starter-generator
Alternator
Batteries
Ground cart

Question 4

Direct Drive Brushless Alternator (DDBA)

Answer 4

Aux power source for SATCOM

Question 5

Permanent Magnet Alternator (PMA)

Answer 5

Powers bus 2 and O ring diode via DCPS 4
Backup power to critical systems

Question 6

Batteries

Answer 6

Bus 1 has 3 batteries
Bus 2 has 2 batteries

“Battery - sourcing current” Could indicate starter-gen failure or GCU malfunction

Question 7

Ground power panel

Answer 7

Located on the fuselage in front of the left wing

Powered by ground cart

Question 8

AC Power Module (ACPM)

Answer 8

Regulates and distributes power to: payloads
weapons systems
DCPS1-3

Acts as circuit breaker protection.

Question 9

DC Power Supply (DCPS)

Answer 9

4 installed
DCPS 1-3 receives AC from ACPM, converts and feeds 28V DC to Bus 1

DCPS 4 receives AC from alternator, converts and feeds 28V DC to Bus 2

Question 10

Ops Limits

Answer 10

Bus 1 Nominal= 0-270A & 25-30V
Bus 1 Max= 300A & 32V

Bus 2 nom= 0-90A(gnd) 0-120(flt) &25-30V
Bus 2 max= 32V

DCPS nom= 0-100A & 25-30V
DCPS max= 120A & 32V

Question 11

Payload Power Distro Modules (PPDM)

Answer 11

2, each equipped w/16 28V DC switched outlets

-Each switch outlet is equipped with 2 discrete outputs (totalling at 32 per switch)