Cessna 182T 2001, Pilot Operating Handbook

Page: 211 / 254

CESSNA SECTION 7
MODEL 182T AIRPLANE & SYSTEMS DESCRIPTION
Normally, both sides of the master switch should be used
simultaneously; however, the BAT side of the switch could be turned
on separately to check equipment while on the ground. To check or
use avionics equipment or radios while on the ground, the avionics
power switch must also be turned on. The ALT side of the switch,
when placed in the off position, removes the alternator from the
electrical system. With this switch in the off position, the entire
electrical load is placed on the battery. Continued operation with the
alternator switch in the off position will reduce battery power low
enough to open the battery contactor, remove power from the
alternator field, and prevent alternator restart.
AVIONICS MASTER SWITCH
Electrical power for Avionics Bus 1 and Avionics Bus 2 is
supplied through Primary circuit breakers. A rocker switch, located
between the primary and avionics 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 switches
in the down (OFF) position removes power from both buses. The
switch is located on the lower left side of the instrument panel.
With the avionics master switch in the off position, no electrical
power will be applied to the avionics equipment, regardless 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, starting 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 affected avionics bus off-line.
Apr 30/01 7-37