Master Switch; Avionics Power Switch; Ammeter - Cessna SKYLANE RG R182 Pilot Operating Handbook

CESSNA
MODEL R182
MASTER SWITCH
SECTION 7
AIRPLANE
&
SYSTEMS DESCRIPTIONS
The master switch is a split-rocker type switch labeled MASTER. and
is ON in the up position and off in the down position. The right half of the
switch, labeled BAT, controls all electrical power to the airplane. The left
half. labeled ALT. controls the alternator.
Normally. both sides of the master switch should be used simultcme-
ously; however, the BAT side of the switch could be turned ON separately
to check equipment while on the ground. To check or use a\'ionics
equipment or radios while on the ground, the avionics power switch must
be
tun1F~d
ON. The ALT side of the switch. when placed in the off position.
removes the alternator from the electrical system. With this s\vitch in the
off position, the entire electrical load is placed on the battery. Continued
operation with the alternator switch in the o!£ position \~Till reduce battery
power low enough to open the battery contactor, remove power from the
alternator field, and prevent alternator restart.
AVIONICS POWER SWITCH
Electrical power from the airplane primary bus
to
the aVIOnics bus
(see figure 7-8) is controlled by a single rocker-type circuit breaker-switch
labeled A VN PWR. The switch is located on the right side of the avionics
circuit breaker panel and is 01\
.1
c ;
he up positlOn and OFF:
r\
the down
position. With the switch in the OFF r>osition. no electrical p(''.ver
vei
il be
applied to the avionics equipment.
I'Pg;"c(1 .",.
of
the
POS"it
i
o l
~h~' ma~.,ter
switch or the individual equipment switches '1'he avionF':s
pen",.. sv.';tch
also functions as a circuit breaker.
If
an electrical malfunction should
occur and cause the circuit breaker to open, electrical power to the avionics
equipment will be interrupted and the switch breaker 'Nlll autornatically
move to the OFF position. If this occurs. allow the circui: breaker
approximately two minutes to cool before placing the breaker
In
the ON
position again.
If
the circuit breaker opens again, do not reset it. The
avionics power switch should be placed in the OFF poslt,on prior to
turning the master switch on or off, starting the engine. or appl,ving an
external power source, and may be utilized in place of the individual
avionics equipment switches.
AMMETER
The ammeter indicates the flow of current
In
amperes. from the
alternator to the b2.ttery or from the battery
to
the airplane electrical
system. When the engine is operating and the master switch is turned
Oil,
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.
7-31