Garmin GNS 480, Installation Manaul

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Installation Procedures
GNS 480 (CNX80) Installation Manual 560-0982-01 Rev L 2-1
2 Installation
This section describes the installation of the GNS 480 including mounting, wiring, and connections. Post-
Installation configuration and checkout procedures are included in section 3.
2.1 Pre-Installation Information
Always follow acceptable avionics installation practices per FAA Advisory Circulars (AC) 43.13-1B,
43.13-2A, or later FAA approved revisions of these documents.
Follow the installation procedure in this section as it is presented for a successful installation. Read the
entire section before beginning the procedure. Prior to installation, consider the structural integrity of the
GNS 480 installation as defined in AC 43.13-2A, Chapter 1. Perform the post installation checkout before
closing the work area in case problems occur.
Complete an electrical load analysis in accordance with AC 43.13-1B, Chapter 11, on the aircraft prior to
starting modification to ensure aircraft has the ability to carry the GNS 480 load. Refer to Section 2.11 for
the power consumption of each GNS 480 mode of operation. Document the results of the electrical load
analysis on FAA Form 337.
The WAAS/GPS installation instructions have been prepared to meet the guidance material defined in
AC20-138A Airworthiness Approval of Global Navigation Satellite System (GNSS) Equipment. The
communications installation instructions have been prepared to meet the guidance material defined by AC
20-67B Airborne VHF Communications Equipment Installations.
2.2 Installation Overview
A successful installation should start with careful planning, including determination of mounting location
for the GNS 480, cable routing, and other required modifications. Once the mounting location has been
determined, prepare the mounting tube for installation. It may be easier to complete the wiring harness and
attach the connectors to rear connector plate before attaching it to the mounting tube.
Carefully plan which external devices will be connected to the GNS 480 inputs.
2.3 Materials Not Supplied
2.3.1 Materials Required But Not Supplied
The GNS 480 is intended for use with standard aviation accessories. The following items are required for
the installation, but not supplied:
•
Wire (MIL-W-22759/16 or equivalent)
•
Shielded wire (MIL-C-27500 or equivalent)
•
Mounting screws (8 min. - AN507 6-32 screw with 100º countersink or MS24693 6-32 cadmium
plated carbon steel)
•
Circuit breakers
•
Antennas (other than the A-33 GPS antenna supplied in the kit)
•
Tie wraps or lacing cord
•
Ring terminals (for grounding)
2.3.2 Optional Accessories Not Supplied
For a list of optional accessories that are available but not supplied with the GNS 480, refer to Appendix F.