In Flight - Bus Transfer switch OFF
IDG 1 has failed.
- The BTBs open and power to Transfer Bus
1 and its associated busses is lost.
- The left TRANSFER BUS OFF and
SOURCE OFF lights are illuminated.
- TR 1 and is not powered and power to DC
Bus 1 is lost.
- The AC Standby Bus is powered from the
Inverter and Battery Charger
- The DC Standby Bus is powered by the
battery and the battery is being charged.
- The Cross Bus Tie Relay opens and the
automatic function is lost.
Moving the Bus Transfer switch to OFF in flight
is used only during some electrical abnormal
procedures.
Electrical System SGR