Forward Overhead Panel  700/800/900
Display Selector
Ground Power and Bus Switching Panel
with associated APU Lights and Indicators
Click on the control or light for a description of its function.
Display Selector
Ground Power and Bus Switching Panel
with associated APU Lights and Indicators
APU GEN OFF BUS (APU Generator Off Bus ) Light

Illuminated -

APU is running and not powering a bus.
Generator 2 Switch