Operation Manual Part 2

Aerosoft – Digital Aviation

CRJ-70 & CRJ-900

AOM PART 2

Systems Description

VOL

5-1-26

26-Jul-2017

ALTERNATING CURRENT, AC SYSTEM

During normal operation, the IDGs supply alternating current. The APU

may be used as a backup in case both IDGs fail. In case even the APU

fails, the CRJ is equipped with an Air Driven Generator, ADG, which is

basically a propeller which is extended into the airstream. The ADG can

provide enough power for the most important aircraft systems to be

still able to fly the aircraft.

The IDGs are monitored regarding temperatures, oil pressure and

supplied power. In case of exceedances the affected IDG can be

disconnected automatically. Nevertheless, there is also a possibility by

means of a switch light on the electrical power panel, to disconnect the

IDG manually.

Please bear in mind that a disconnected IDG (no matter if disconnected

automatically or manually) can only be reconnected on ground. Please

open Dave, go to the “Services / Maintenance” page to reconnect the

IDG. Disconnected IDGs are displayed in blue. Press on “Reconnect”

and “Save” to reconnect.

Before disconnecting you may try to reset the IDG by switching the generator switch on the electrical control

panel to OFF/RESET and then back to ON.