Garmin GRS 77, Руководство по установке

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GRS 77/GMU 44 Installation Manual Page 5-13
190-00303-10 Revision L
5.8 Calibration Procedure E: Magnetometer Interference Test
NOTE
Calibration Procedure E is required for initial installation certification.
This test should also be repeated to verify all subsequent electrical
changes associated with devices within 10.0 feet of the GMU 44
magnetometer. Such changes include, but are not limited to, wiring,
shielding or grounding changes to any light, strobe, beacon or other
electrical device located in the same wing as a GMU 44 unit. Likewise,
this test should also be repeated to verify all subsequent changes to
materials within 10.0 feet of the GMU 44. Such changes include, but are
not limited to, addition, removal or modification of ferrous or electrically
conductive materials located in the same wing as a GMU 44 unit. This
procedure validates that no electronic device is interfering with the
operation of the GMU 44 magnetometer which directly impacts the
determination of attitude and heading by the GRS 77 AHRS. Calibration
Procedures A-1 through D are not required prior to this execution of this
procedure.
Garmin recommends this test be performed at least once every 12 months
by all aircraft manufacturers on a minimum of one production aircraft for
every airframe type or model equipped with the G1000 system.
1. Initiate the AHRS magnetometer interference test procedure by performing the following steps:
a) If the PFD is not displaying the GRS/GMU CALIBRATION configuration page, follow steps
from calibration procedure A-1.
b) The FMS small knob can now be used to select which calibration/validation procedure to run.
Select MAG INTERFERENCE TEST and press the ENTER key. If the MAG
INTERFERENCE TEST selection is still blinking, press the ENTER key again.
c) Follow the checklist items displayed on the PFD, and press the ENTER key as each one is
completed or confirmed.
NOTE
The third item on the checklist instructs the operator to prepare a detailed
test sequence list with precise start and stop times for exercising all
electronic devices. Only the electronic devices that are likely to affect
the operation of the GMU 44 magnetometer need be included in the test
sequence. The list of relevant electronic devices varies from aircraft to
aircraft. An example of an appropriate test sequence for both a fixed-
wing aircraft and a helicopter is given in Tables 5-2 and 5-3.