General Specifications; Mounting And Wiring Requirements - Garmin G3X Installation Manual

12.3 General Specifications

See Section 2.2 for power/current specifications, and

12.4 Mounting and Wiring Requirements

12.4.1 Panel Cutout Template
Figure 12-6 can be used as a template when marking the panel for cutout. Dimensions on the figure are to
verify accuracy of printout only, see
12.4.2 Unit Installation
Fabrication of a wiring harness is required. Sound mechanical and electrical methods and practices are
recommended for installation of the GMC 307. Refer to
Section 23.6 for pinouts.
1. Per Figure 12-2, ensure the pawl latch fasteners are fully retracted and in the vertical position.
2. Hold the unit flush with the instrument panel.
3. Using a 3/32" hex drive tool turn each of the two pawl latches clockwise until tightened to
20 +/-2 in-lbs. When tightened, the pawl latches are in the horizontal position.
12.4.3 Wiring
The 15 pin connector, pins, and backshell supplied in the GMC 307 installation kit are used to add wiring
for the GMC 307.
It is recommended that a 2 Amp fuse or circuit breaker be used to supply power to the GMC 307
(Figure 24-1.6). Backup power is optional.
The GMC 307 is connected via RS-232 to any GDU 37X/4XX display
RS-232 channel must be configured for "Garmin Instrument Data".
If the installation includes a Garmin integrated autopilot using GSA 28 servos, the GMC 307 installation
also includes an RS-232 connection to the GSA 28 roll servo
must be connected to any one of the available RS-232 channels on one of the GDU 37X/4XX units. The
GMC 307 RS-232 channel 2 must be connected to the GSA 28 roll servo RS-232 channel 1 if this roll
servo is installed.
For installations using a non-Garmin autopilot with a GMC 307 controller, refer to
190-01115-01
Rev. AA
Section 2.4.1
Figure 12-5 for complete cutout dimensions.
Section 2.3
Figure 12-2. Pawl Latch
G3X/G3X Touch Installation Manual - GMC 307 Installation
for dimension/weight specifications.
for wiring considerations, and to
(Figure 24-1.6). The selected GDU
(Figure 24-1.6). GMC 307 RS-232 channel 1
Figure 24-2.18.
Page 12-2