Ammeter Select Switch; Low-Volts Warning Light; Alt Fail Caution Lights - Cirrus SR22 Pilot Operating Handbook

Cirrus Design
SR22

Ammeter Select Switch

Serials 0002 through 1601, 1603 through 1643 and 1645 through
1662: The AMMETER SELECT switch on the instrument panel is used
to select the desired source of electrical current flow to be indicated on
the ammeter. The switch has three positions: ALT 1, BATT, and ALT 2.
The BATT position indicates BAT 1 current flow only. Selecting one of
the switch positions will cause the amperage output from that device to
be displayed on the ammeter.
Serials 1602, 1644, 1663 and subsequent: Main and Essential Bus
voltages are displayed on the MFD and PFD, therefore, no ammeter
select switch is necessary.

Low-Volts Warning Light

The airplane is equipped with a red LOW VOLTS warning light in the
annunciator panel located on the left side of the instrument panel. A
voltage sensor in the (MCU) monitors voltage on the Essential Bus
and illuminates the warning light when the voltage is less than
approximately 24.5 volts.
The LOW VOLTS warning light may come on during extended
low RPM operation with heavy electrical loads. Under these
conditions, the light will go out at higher RPM.

ALT Fail Caution Lights

Two ALT Fail caution lights are installed in the annunciator panel. The
ALT 1 and ALT 2 caution lights in the annunciator panel provide
annunciation of alternator failure or overcurrent conditions at the
respective alternator. The lights are operated by circuits in the MCU
and current sensors on the ALT 1 and ALT 2 output lines. Steady
illumination of either light indicates an alternator failure. Serials 0002
through 1601, 1603 through 1643 and 1645 through 1662: A flashing
ALT light indicates an overcurrent condition.
P/N 13772-001
Revision A7
• Note •
Section 7
Airplane Description
7-71