Nstallation; Materials Not Supplied - Garmin GDL 90 Installation Manual

2 Installation
This section describes the installation of the GDL 90 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
GDL 90 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 GDL 90 load. Refer to Section 2.10 for
the power consumption of each GDL 90 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.
Operating the GDL 90 without RF terminations on the Top or Bottom UAT Antenna
ports can result in equipment damage. Always operate the GDL 90 with the Top and
Bottom UAT Antenna ports terminated with a VSWR ratio of 3.0:1 or less.
2.2 Installation Overview
A successful installation should start with careful planning, including determination of mounting location
for the GDL 90, cable routing, and other required modifications. Once the mounting location has been
determined, prepare the mounting tray for installation. It may be easier to complete the wiring harness
and attach the connectors to the tray upon installation.
2.3

Materials Not Supplied

2.3.1 Materials Required But Not Supplied
The GDL 90 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)
Circuit Breakers
Ring Terminals (for grounding)
GDL 90 Installation Manual
CAUTION
560-1049-02 Rev. B
Installation Procedures
2-1