Avionics Master Switch; Ammeter - Cessna 182S Pilot Operating Handbook

CESSNA
MODEL 182S
SECTION 7
AIRPLANE
&
SYSTEMS DESCRIPTION
AVIONICS MASTER SWITCH
Electrical power for Avionics Bus 1 and Avion ics Bus 2 is
supplied through Primary Bus 1 and Primary Bus 2, respectively. A
rocker switch , located between the primary and avion ics buses,
controls current flow to the avionics buses. Placing the rocker
switch in the up (ON) position supplies power to both buses
simultaneously. Placing the switch in the down (OFF) position
removes power from both buses. The switch is located on the lower
left side of the instrument panel.
NOTE
On some aircraft cerlilied outside the United States, the
avionics master switch may be split. They are aligned for
independent operation of the buses.
With the switch in the off position, no electrical power will be
applied to the avionics equipment, regard less of the position of the
master switch or the individual equipment switches. The avionics
master switch should be placed in the OFF position prior to turning
the master switch on or off, starling the engine, or applying an
external power source.
Each avionics bus also incorporates a separate circuit breaker
installed between the primary bus and the avionics master switch. In
the event of an electrical malfunction , this breaker will trip and take
the effected avionics bus off-line.
AMMETER
The ammeter/vacuum gauge is located on the lower left side of
the instrument panel. It indicates the amount of current, in amperes,
from the alternator to the battery or from the battery to the airplane
electrical system. When the engine is operating and the master
switch is turned on , the ammeter indicates the charging rate applied
to the battery. In the event the alternator is not functioning or the
electrical load exceeds the output of the alternator, the ammeter
indicates the battery discharge rate.