Gsu 25/73 & Gmu 22 Post-Installation Calibration - Garmin G3X Installation Manual

31.4.3.1 GSU 25/GSU 73/GMU 22 Post-Installation Calibration Procedures
After mechanical and electrical installation of the GSU 25/GSU 73 AHRS and GMU 22 magnetometer
have been completed, prior to operation, a set of post-installation calibration procedures must be carried
out.
The calibration procedures
the GSU Page (configuration mode) indicate a positive state (green check marks) before starting the
procedure. Table 31-2 and
Table 31-1 describes the calibration procedures:
Table 31-1 Post Installation Calibration Procedure Summary
Calibration
Procedure Name
Procedure
A Unit Orientation
Pitch/Roll Offset
B
Compensation
Magnetic
C
Interference Test
Magnetometer
D
Calibration
Engine Run-Up
E
Vibration Test
ADAHRS Static
F Pressure
Calibration
190-01115-01 G3X/G3X Touch Installation Manual - GDU 37X Config and Post Install Checkout
Rev. AA
(Section 31.4.3.2 – Section
Table 31-3 list the status box requirements for each calibration procedure.
Procedure
Description
Validate GSU
Orientation
Level Aircraft
Validate no
magnetic
interference
with GMU 22
Compass Rose
Taxi Maneuver
Validate
vibration
characteristics
of installation
Altitude
re-calibration
31.4.3.6) may require that certain status boxes on
Installations Requiring Procedure
Procedure A is required for all installations
Procedure B is required for all installations
Procedure C is required for initial installation
verification.
This test should also be repeated to verify all
subsequent electrical changes associated with
devices within 10.0 feet of the GMU 22
magnetometer. Such changes include, but are
not limited to, wiring, shielding or grounding
changes to any light, strobe, beacon or other
electrical device located near or in the same wing
as the GMU 22 unit. Likewise, this test should
also be repeated to verify all subsequent changes
to materials within 10.0 feet of the GMU 22. Such
changes include, but are not limited to, addition,
removal or modification of ferrous or electrically
conductive materials located near or in the same
wing as the GMU 22 unit.
Garmin recommends this test be performed at
least once every 12 months.
Procedure D is required for all installations.
This calibration must be performed after every
Pitch/Roll Offset Compensation and following a
removal or replacement of the GMU 22 unit, or
degaussing of the area near the GMU 22 location.
Procedure E is required for all installations
Procedure F is only used when an ADAHRS has
failed a periodic altimeter test
Page 31-9