Dec 2/96; Electrical Power Supply System Malfunctions; Ammeter Shows Excessive Rate Of Charge (Full Scale Deflection); Low Voltage Annunciator (Volts) Illuminates During Flight (Ammeter Indicates Discharge) - Cessna 172R Pilot Operating Handbook

ELECTRICAL POWER SUPPLY SYSTEM
MALFUNCTIONS
AMMETER SHOWS EXCESSIVE RATE OF CHARGE
(Full Scale Deflection)
Alternator -- OFF.
A
CAUTION
WITH THE ALTERNATOR SIDE OF THE MASTER
SWITCH OFF, COMPASS DEVIATIONS OF AS
MUCH AS 25° MAY OCCUR.
Nonessential Electrical Equipment -- OFF.
Flight -- TERMINATE as soon as practical.
LOW VOLTAGE ANNUNCIATOR (VOLTS) ILLUMINATES DURING
FLIGHT
(Ammeter Indicates Discharge)
NOTE
Illumination
of "VOLTS" on the annunciator panel may
occur during low RPM conditions with an electrical load on
the system such as during a low RPM taxi. Under these
conditions, the light will go out at higher RPM. The master
switch need not be recycled since an overvoltage condition
has not occurred to deactivate the alternator system.
.
Avionics Power Switch -- OFF.
Alternator Circuit Breaker -- CHECK IN.
Master Switch -- OFF (both sides).
Master Switch -- ON.
Low Voltage Annunciator -- CHECK OFF.
Avionics Power Switch -- ON.
Dec 2/96
3-11
CESSNA
SECTION 3
MODEL 172R
EMERGENCY PROCEDURES
1.
2. --
3.
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