Garmin GDR 66 Installatioin Manual

GDR 66 Installation Manual Page 2-3190-00303-24 Revision A2.4 Cabling and WiringRefer to the interconnect examples in Appendix B for wire gauge guidance.The power connection can be run with three AWG #18 wires back to the breaker or can be spliced near theunit to one AWG #16 or larger wire. Special thin-wall heat shrink tubing is also provided to insulate theextended barrels inside the backshell. If using AWG #18 barrel contacts, ensure that no two contacts aremounted directly adjacent to each other. This minimizes the risk of contacts touching and shorting toadjacent pins and to ground.Ensure that routing of the wiring does not come in contact with sources of heat, RF or EMI interference.Check that there is ample space for the cabling and mating connectors. Avoid sharp bends in cabling androuting near aircraft control cables.Coaxial cable with 50Ω nominal impedance and meeting applicable aviation regulations should be used forthe installation.RTCA DO-224A assumes 3dB of cable loss in its VDL Typical Uplink PowerBudget. Losses greater than 3dB can reduce transceiver range.Cabling for the GDR 66 should not be routed near components or cabling which are sources of electricalnoise. Route the GPS, VOR/LOC, and Glideslope antenna cables as far as possible away from all COMtransceivers and antenna cables.2.5 Cooling AirDedicated cooling is not required for the GDR 66 to meet indicated EQF categories. Thermal analysismust be performed to verify that high temperature limits implied by the indicated EQF categories for theGDR 66 are not exceeded during normal operation of the aircraft. Guidance can be found in the GarminIntegrated Avionics System Thermal Management Plan document (GPN 190-00313-50) and the GarminIntegrated Avionics System Thermal Validation Procedure (GPN 190-00313-51).Contact Garmin for additional cooling guidance.NOTEDRAFT