NOTICE

SECTION 7 CESSNA
AIRPLANE AND SYSTEMS DESCRIPTION MODEL 208B G1000
AVIONICS POWER SWITCHES
Electrical power from the airplane power distribution bus to the avionics
buses (see Typical Electrical System figure) is controlled by two toggletype
switch breakers located on the left sidewall switch and circuit
breaker panel. One switch controls power to the number 1 avionics bus
while the other switch controls power to the number 2 avionics bus. The
switches are labeled AVIONICS and are ON in the forward position and
OFF in the aft position. The avionics power switches should be placed
in the OFF position prior to turning the battery switch ON or OFF, or
applying an external power source. The number 1 AVIONICS Switch
must be ON.
U.S.
WARNING
Failure to have AVIONICS No. 1 ON will result in an
over temperature and image damage.
AVIONICS STANDBY POWER SWITCH
The avionics standby power system switch is a guarded two-position
switch/breaker, labeled AVIONICS STBY PWR. The guard covering
this switch must be lifted in order to select the ON position. When
switched ON, the standby electrical system directly provides power to
the Avionics bus 1. When switched OFF, the standby electrical system
may provide extra power to the avionics busses via the main power
distribution bus, provided the STBY PWR circuit breakers on the
electrical busses are not pulled. When operating solely on standby
power, both AVIONICS 1 and 2 power switches should be OFF to avoid
feeding a possible fault in the primary power system.
AVIONICS BUS TIE SWITCH
The avionics bus tie switch is a two-position guarded toggle-type switch
located on the left sidewall switch and circuit breaker panel. The switch
connects the number 1 and number 2 avionics buses together in the
event of failure of either bus feeder circuit. Because power for each
avionics bus is supplied from a separate current limiter on the power
distribution bus, failure of a current limiter can cause failure of the
affected bus. Placing the bus tie switch to the ON position will restore
power to the failed bus. Operation without both bus feeder circuits may
require an avionics load reduction, depending on equipment installed.
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208BPHBUS-00