Wiring/Cabling Considerations - Garmin G3X Touch Installation Manual

LRU
GSA 28
GSU 25
GSU 73*
14 Vdc
GTR 20
GTR 200**
28 Vdc
*Garmin recommends using Mod 1 level GSU 73 in aircraft that use a +28 V supply voltage and intend to monitor
current on high voltage devices such as the aircraft alternator.
**The specified current draw is measured with the display backlight set to 100%

2.3 Wiring/Cabling Considerations

Section 25 lists the pin information for all LRU connectors.
configuration modules) installation information. Section 26 through Section 32 contain interconnect
drawings for all required/optional LRUs and sensors. These sections, along with the Section 4 through
Section 22 contain all the information needed to construct the wiring harnesses/cables. It is recommended
that LRUs/sensors be installed prior to constructing the wiring harnesses and cables.
Use MIL-W-22759/16 (or other approved wire) AWG #22 or larger wire for all connections unless
otherwise specified. The supplied standard pin contacts 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.
Use MIL-C-27500 (or other approved cable) for all shielded cable connections unless otherwise specified.
HSDB (Ethernet) connections may use either aviation grade Category 5 Ethernet cable, or MIL-C-27500
shielded twisted-pair cable.
RG400 or RG142 coaxial cable with 50 Ω nominal impedance and meeting applicable aviation regulations
should be used for the installation.
190-01115-01
Rev. AC
Table 2-2 G3X LRU Power Requirements
Supply Voltage
0.36 Amp (typical)
14 Vdc 1.80 Amp (max)
2.80 Amp (max with 1 Amp trim motor at full load)
0.20 Amp (typical)
28 Vdc 0.90 Amp (max)
1.40 Amp (max with 1 Amp trim motor at full load)
14 Vdc 0.2 Amp (includes GMU 22 load)
28 Vdc 0.11 Amp (includes GMU 22 load)
14 Vdc 1.75 Amp (max)
28 Vdc 0.80 Amp (max)
0.6 Amp, Typical when receiving
3.0 Amp, Typical when transmitting
7.50Amp, Maximum, 90% modulated into 3:1
VSWR and 11V power input voltage
0.30 Amp, Typical when receiving
1.40 Amp, Typical when transmitting
3.75 Amp, Maximum, 90% modulated into 3:1
VSWR and 22 V power input voltage
G3X/G3X Touch Installation Manual - Installation Preparation
Current Draw
Section 25 lists the connector (including
Page 2-14