Specifications

Information Manual 7-73
Cirrus Design Section 7
SR20 Airplane Description
Ammeter Select Switch
Serials 1268 through 1581: 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 1582 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.
• Note •
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 1268
through 1581: A flashing ALT light indicates an overcurrent condition.
March 2010