Garmin GNC 420, Руководство по установке

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Page 5-18 400 SERIES INSTALLATION MANUAL
Rev Q 190-00140-02
5.3 ADDITIONAL GROUND TESTS
5.3.1 Connector Engagement Test
1. Turn on the 400 Series unit, and turn on the avionics master switch (if applicable).
2. Place the 400 Series unit in the rack and engage the pawl mechanism.
3. Turn the Allen screw of the locking pawl slowly clockwise until the 400 Series unit just comes on. A
“T” handle makes the turns easy to count, but do not over-tighten.
4. Count the number of complete revolutions you can turn the Allen screw until it can not turn any more
(but take care not to over-tighten). Three turns is the minimum for proper installation. If fewer than
three turns are possible, the mounting rack should be moved aft such that the aircraft panel does not
obstruct the unit from engaging in the rack.
5.3.2 Verification of Self-Test Data
Following normal power-up, the Self-Test Page is displayed followed by the Data Base Page. Pressing the
ENT key once then displays the Instrument Panel Self-Test page (refer to Figure 5-7 on page 5-6). During
this time, many of the electrical outputs are activated so the installation, configuration, and wiring may be
verified. Before approving the Data Base Page, verify that the following parameters are displayed on
equipment in the aircraft as listed below:
NOTE
Electronic displays which monitor the 400 Series unit’s ARINC 429 output may vary in
how and where annunciations are displayed. Generally, it is not required to verify every
data field with an ARINC 429 interface. Correct display of a subset of the data without
noting any discrepancies is typically adequate evidence of correct ARINC 429 operation.
Parameter Self-test Value
Course Deviation Half-scale left deviation, TO indication, flag pulled
Glideslope/Vert. Deviation Half-scale up deviation, flag pulled
Bearing to Waypoint 135º
Desired Track
149.5º
Selected Course
149.5º
Distance to Go 10.0 nautical miles
Time to Go 4 minutes
Active Waypoint “GARMN”
Groundspeed 150 knots
Present Position N 39º04.05’, W 94º53.86’
Waypoint Alert Active
Phase of Flight
En Route
Message Alert Active
Leg/OBS Mode Leg Mode
GPS Integrity
Reflects actual GPS integrity
5.3.3 Signal Acquisition Test
Upon approval of the Data Base Page, the Satellite Status Page is displayed. If the unit is unable to acquire
satellites, relocate the aircraft away from obstructions which might be interfering with GPS reception. If
the situation does not improve, check the GPS antenna installation.
Once GPS position information is available, use the DIRECT-TO key to activate the navigation function to
a nearby airport, NAVAID, or intersection. Ensure that any connected equipment is transmitting and
or/receiving data from the 400 Series unit and is functioning properly (see the Pilot’s Guide for more
information on the direct-to function).