C
IRRUS
D
ESIGN
S
ECTION
7: A
IRPLANE
AND
S
YSTEMS
SR20
E
LECTRICAL
S
YSTEM
P/N 11934-005
7-53
regardless of the position of the MASTER switch or the individual equip-
ment switches. For normal operations, the AVIONICS switch should be
placed in the OFF position prior to activating the MASTER switches,
starting the engine, or applying an external power source.
Ground Service Receptacle
A ground service receptacle is located just aft of the cowl on the left side of
the airplane. This receptacle is installed to permit the use of an external
power source for cold weather starting and maintenance procedures
requiring reliable power for an extended period. The external power source
must be regulated to 28 VDC. The external power control contactor is
wired through the BAT 1 MASTER switch so that the BAT 1 switch must
be 'on' to apply external power.
Refer to Section 8,
for use of external power and special
precautions to be followed.
Electrical Indicating
Electrical system information is displayed as bar graphs and text on the
MFD’s ENGINE page. When the ENGINE page is not active or in the case
of an electronic display failure (backup mode), Battery 1 ampere output
and Essential Bus voltage output are displayed along the LH edge of the
display. Electrical data is acquired by the Engine Airframe Unit which
transmits the data to the Engine Indicating System for display as described
in the following pages.
• N
OTE
•
A “Red X” through any electronic display field indicates the field
is not receiving valid data and is considered inoperative.
Electrical System Annunciations
Electrical system health, caution, and warning messages are displayed in
color-coded text in the Crew Alerting System (CAS) window located to the
right of the Altimeter and Vertical Speed Indicator. In combination with a
CAS alert, the affected electrical parameter displayed on the ENGINE page
changes to the corresponding color of CAS alert and the annunciation
system issues an audio alert.
• N
OTE
•
For specific pilot actions in response to Electrical System Annun-
ciations, refer to Section 3 - Emergency Procedures,
Reissue A