Textron Cessna C172S PIM, Руководство по эксплуатации для пилотов

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CESSNA SECTION 7
MODEL 172S NAV III AIRPLANE AND SYSTEM DESCRIPTION
GFC 700 AFCS
U.S.
ELECTRICAL SYSTEM
(Continued)
ELECTRICAL SYSTEM MONITORING AND
ANNUNCIATIONS
BUS VOLTAGE (VOLTMETERS)
Voltage indication (VOLTS) for the main and essential buses is
provided at the bottom of the EIS bar, along the left margin of the MFD
or PFD, labeled M BUS E. Main bus voltage is shown numerically
below the M. Essential bus voltage is displayed numerically below the
E. The main bus voltage is measured at the WARN circuit breaker on
the crossfeed bus. The essential bus voltage is measured at the NAV1
ENG circuit breaker on the essential bus.
Normal bus voltages with the alternator operating shall be about 28.0
volts. When the voltage for either main or essential buses is above 32.0
volts, the numerical value and VOLTS text turns red. This warning
indication, along with the HIGH VOLTS annunciation, is an indication
that the alternator is supplying too high of a voltage. The ALT MASTER
Switch should immediately be positioned to OFF (Refer to Section 3,
Emergency Procedures, HIGH VOLTS ANNUNCIATOR COMES ON).
When the voltage for either main or essential buses is below 24.5 volts,
the numeric value and VOLTS text turns red. This warning indication,
along with the LOW VOLTS annunciation, is an indication that the
alternator is not supplying all the power that is required by the airplane.
Indicated voltages between 24.5 and 28.0 volts may occur during low
engine RPM conditions. Refer to note under LOW VOLTAGE
ANNUNCIATION.
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172SPHBUS-02 7-53