SECTION 7
CESSNA
AIRPLANE AND SYSTEMS DESCRIPTION
MODEL 172S NAV III
ELECTRICAL SYSTEM
(Continued)
G1000 ANNUNCIATOR PANEL
All system alerts, cautions and warnings are shown on the right side
of the PFD screen adjacent to the vertical speed indicator. The
following annunciations are supported:
OIL PRESSURE
LOW VACUUM
LOW FUEL L
LOW FUEL R
LOW VOLTS
PITCH TRIM
HIGH VOLTS
CO LVL HIGH (if installed)
STBY BAT
Refer to the Garmin G1000 Cockpit Reference Guide Appendix A
for more information on system annunciations.
MASTER SWITCH
The MASTER switch is a two-pole, rocker-type switch. The BAT
side of the switch controls the main battery electrical power to the
airplane. The ALT side of the switch controls the alternator system.
In normal operation, both sides of the switch (ALT and BAT) are ON
simultaneously; however, the BAT side of the switch may be
selected separately as necessary. The ALT side of the switch can
not be set to ON without the BAT side of the switch also being set
to ON.
If the alternator system fails, the MASTER switch may be set to the
OFF position to preserve Main Battery capacity for later in the flight.
With the MASTER switch OFF and the STBY BATT switch in the
ARM position, the standby battery will power the Essential Bus for a
limited time. Time remaining may be estimated by monitoring
Essential Bus Voltage. At 20 Volts, the standby battery has little or
no capacity remaining.
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7-48 U.S.
172SPHAUS-03
