Operation Manual Part 2

Aerosoft – Digital Aviation
CRJ-70 & CRJ-900
AOM PART 2
Systems Description
VOL
5
5-1-28
26-Jul-2017
CONTROLS ON OVERHEAD PANEL
1. DC SERVICE: Connects the DC service bus to the APU battery direct bus
2. BATTER MASTER: Used to supply the battery bus with power from the APU or main direct busses.
Always ON in flight!
3. AC: External Power toggle
- AVAIL indicates connected source
- IN USE indicates AC busses are connected to external power unit
4. IDG1/2 DISCONNECT: Open guard and press push button to disconnect IDG1 (reconnect on ground
only!)
- DISC (white) indicates IDG is disconnected
- FAULT (amber) indicates low oil pressure or high temperature
5. AC ESS XFER: Switches essential bus feed from AC bus 1 to AC bus 2, switches automatic in case of
IDG1 failure
- ALTN (white) indicates essential bus is fed from AC bus 2
6. GEN 1: Used to switch generators between AUTO and OFF
7. AUTO XFER: Disables automatic transfer of respective IDG
- OFF indicates autotransfer is deactivated
- FAIL indicates a fault is preventing autotransfer