NOTICE

SECTION 7 CESSNA
AIRPLANE AND SYSTEMS DESCRIPTION MODEL 208B G1000
GENERATOR CONTROL UNIT
The generator control unit (GCU) is mounted inside the cabin on the left
forward fuselage sidewall. The unit provides the electrical control
functions necessary for the operation of the starter-generator. The GCU
provides for automatic starter cutoff when engine RPM is above 46%.
Below 46%, the starter-generator functions as a starter, and above
46%, the starter-generator functions as a generator when the starter
switch is OFF. The GCU provides voltage regulation plus high voltage
protection and reverse current protection. In the event of a high-voltage
or reverse current condition, the generator is automatically
disconnected from the buses. The generator contactor (controlled by
the GCU) connects the generator output to the airplane bus. If any
GCU function causes the generator contactor to de-energize, the
Amber GENERATOR OFF CAS MSG will illuminate.
GROUND POWER MONITOR
The ground power monitor is located inside the electrical power control
assembly mounted on the left hand side of the firewall in the engine
compartment. This unit senses the voltage level applied to the external
power receptacle and will close the external power contactor when the
applied voltage is within the proper limits.
BATTERY SWITCH
The battery switch is a two-position toggle-type switch, labeled
BATTERY, and is located on the left sidewall switch and circuit breaker
panel. The battery switch is ON in the forward position and OFF in the
aft position. When the battery switch is in the ON position, battery
power is supplied to the two general buses. The OFF position cuts off
power to all buses except the battery bus.
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U.S.
208BPHBUS-00