Wiring/Cabling Considerations - Garmin G300 Installation Manual

1.6 Wiring/Cabling Considerations

Use MIL-W-22759/16 (or other approved wire) AWG #24 or larger wire for all connections unless
otherwise specified. The standard pin contacts supplied in the connector kit are compatible with up to
AWG #22 wire. In cases where some installations have more than one LRU sharing a common circuit
breaker, sizing and wire gauge is based on aircraft circuit breaker layout, length of wiring, current draw
on units, and internal unit protection characteristics. Do not attempt to combine more than one unit on the
same circuit breaker unless it is specified on aircraft manufacturer approved drawings.
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 and
routing near aircraft control cables.
RG400 or RG142 coaxial cable with 50 Ω nominal impedance and meeting applicable aviation
regulations should be used for the installation.
Check that there is ample space for the cabling and mating connectors. Avoid sharp bends in cabling and
routing near aircraft control cables. Cabling for the G300 should not be routed near components or
cabling which are sources of electrical noise. Route the GPS antenna cable as far as possible away from
all COM transceivers and antenna cables.
1.6.1 Wiring Harness Installation
Allow adequate space for installation of cables and connectors. The installer shall supply and fabricate all
of the cables. Electrical connections are made through D subminiature connectors for the GDU 37X and
GSU 73 units, and through a round 9-pin connector for the GMU 44. Appendix A defines the electrical
characteristics of all input and output signals. Required connectors and associated hardware are supplied
with the connector kit.
Check wiring connections for errors before connecting any wiring
harnesses. Incorrect wiring could cause internal component damage.
G300 Installation Manual – Installation Overview
190-00921-01
CAUTION
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Revision A