Cirrus DESIGN SR20 Information Manual page 298

Section 9
Supplements
1. Affected ALT Master Switch .....................................................OFF
2. Affected ALT Circuit Breaker .................................................. PULL
3. Nonessential Electrical Equipment ..........................................OFF
4. Land as soon as practical.
Battery Ammeter Indicates Discharge
In the event of a failure of an alternator, the associated ALT FAIL
caution light illuminates. If both alternators fail, both ALT FAIL lights
will illuminate, the LOW VOLTS warning light will illuminate when the
bus voltage drops to approximately 24.5 volts, and a discharge rate will
be shown on the battery ammeter. An attempt should be made to
reactivate the alternator system by following the checklist below. If the
condition clears, normal alternator charging will resume, the warning
and caution lights will go out, and avionics power may be turned back
on. However, if the lights come on again, a malfunction is confirmed
and the procedure should be completed. Battery power must be
conserved for later operation of the wing flaps, lights, and other
essential equipment.
Ammeter discharge indications and illumination of the LOW
VOLTS warning light and/or illumination of one or both ALT
FAIL caution lights can occur during low RPM conditions with
a heavy electrical load, such as during low-speed taxi. Under
these conditions, the master switch(es) need not be cycled as
an over-voltage condition has not occurred and the alternator
was not de-activated. The lights should go out at higher RPM.
1. Alternator Circuit Breakers .............................................CHECK IN
2. Ammeter Select Switch ..........................................................ALT 1
3. If Amps = 0, ALT 1 Master Switch ................... CYCLE (OFF – ON)
4. If Amps remain = 0
a. ALT 1 Master Switch .........................................................OFF
b. Alternator 1 Circuit Breaker ............................................ PULL
5. Repeat steps 2. thru 4. for ALT 2.
6. Ammeter Select Switch .......................................................... BATT
7. Non-essential Electrical Equipment .........................................OFF
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• Note •
Cirrus Design
SR20
P/N 11934-S10
Original: 09-28-99