Garmin GDL 90 Installation Manual

Also see for GDL 90: Installation manual

Installation ProceduresGDL 90 Installation Manual 560-1049-00 Rev B 2-12 INSTALLATIONThis 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 INFORMATIONAlways 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 theentire section before beginning the procedure. Prior to installation, consider the structural integrity of theGDL 90 installation as defined in AC 43.13-2A, Chapter 1. Perform the post installation checkout beforeclosing 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 tostarting modification to ensure aircraft has the ability to carry the GDL 90 load. Refer to Section 2.10 forthe power consumption of each GDL 90 mode of operation. Document the results of the electrical loadanalysis on FAA Form 337.The WAAS/GPS installation instructions have been prepared to meet the guidance material defined inAC20-138A Airworthiness Approval of Global Navigation Satellite System (GNSS) Equipment.CAUTIONOperating the GDL 90 with no RF terminations on the Top or Bottom UAT Antennaports can result in equipment damage. Always operate the GDL 90 with the Top andBottom UAT Antenna ports terminated with a VSWR ratio of 3.0:1 or less.2.2 INSTALLATION OVERVIEWA successful installation should start with careful planning, including determination of mounting locationfor the GDL 90, cable routing, and other required modifications. Once the mounting location has beendetermined, prepare the mounting tray for installation. It may be easier to complete the wiring harnessand attach the connectors to the tray upon installation.2.3 MATERIALS NOT SUPPLIED2.3.1 MATERIALS REQUIRED BUT NOT SUPPLIEDThe GDL 90 is intended for use with standard aviation accessories. The following items are required forthe installation, but not supplied:• Wire (MIL-W-22759/16 or equivalent)• Shielded wire (MIL-C-27500 or equivalent)• Circuit breakers• Ring terminals (for grounding)