Page 2-4
GMA 1347D Installation Manual
Revision C
190-00303-21
2.4
Cabling & Wiring
Use AWG #24 or larger wire for all connections unless otherwise specified by the aircraft manufacturer
or Garmin. 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 unit sharing a common circuit breaker, sizing
and wire gauge is based on aircraft circuit breaker layout, length of wiring, current draw of 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.
In some cases, a larger gauge wire such as AWG #16, #18, or #20
may be needed for power connections.
The provided connector kit supplies extended barrel contacts for AWG #16 and #18 wire, if required.
Special thin-wall heat shrink tubing is also provided to insulate the extended barrels inside the backshell.
If using #16 or #18 barrel contacts, ensure that no two contacts are mounted directly adjacent to each
other. This minimizes the risk of contacts touching and shorting to adjacent 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 and
routing near aircraft control cables.
2.5 Cooling
Air
The GMA 1347D does not have provisions for attaching cooling air and does not generate an excessive
amount of heat during typical operations, however the thermal characteristics of the installation should
always be assessed. An undesirable thermal condition could be created due to the unit's own internal
power dissipation combined with restricted ventilation, or due to heat generated by adjacent equipment.
Limiting thermal build up, by means of fan or natural convection is always a good practice and
recommended to increase the product life. Refer to the G1000 System Installation manual, Garmin part
number 190-00303-00, for information on cooling requirements.
