Power; Table 5-3 Power Pins; Table 5-4 Power Configuration And Control Inputs; Table 5-5 Power Configuration And Power Control Functions - Garmin GTX 3X5 Series Installation Manual

5.3

Power

The GTX 3X5 is compatible with 14 VDC and 28 VDC aircraft electrical systems. The AIRCRAFT POWER 2 input is
diode-isolated from AIRCRAFT POWER 1 and is used for connecting to an alternate power source, such as on an
aircraft with two electrical buses.
AIRCRAFT POWER 1
AIRCRAFT POWER 1
AIRCRAFT POWER 2
AIRCRAFT POWER 2
AIRCRAFT GROUND
AIRCRAFT GROUND
SWITCHED POWER OUT
GPS KEEP ALIVE [1]
[1] Applicable to the GTX 335 and GTX 345 with internal GPS only.
The SWITCHED POWER OUT pin is a switched power output source, typically used for powering devices such as a
remote altitude encoder module. It is active when the GTX 3X5 power is on, and has a 1 ampere max rating.
On models with built-in GPS/SBAS, the GPS KEEP ALIVE input is optional. Continuous battery input power maintains
the internal GPS clock and decreases initial GPS satellite acquisition time during system power-up.

5.3.1 Power Configuration and Control Inputs

The power control inputs are for remote power on/off and enabling the power auto on feature.
The POWER CONFIG input controls the remote on/off feature. The POWER CONFIG input connects to ground for
remote unit installation. The input is left open for panel mount unit installation.
The POWER CONTROL connection controls the POWER CONTROL input. This is used as a remote power on/off control
or to use the power auto on feature when the avionics master is turned on.
POWER CONFIG
POWER CONTROL

POWER

CONFIG CONTROL
Open Open
Open Ground
Ground Open
Ground Ground
190-01499-02
Rev. 9

Table 5-3 Power Pins

Pin Name

Table 5-4 Power Configuration and Control Inputs

Pin Name

Table 5-5 Power Configuration and Power Control Functions

POWER
Unit Type
Panel mount
Panel mount
Remote
Remote
Connector
P3251
P3251
P3251
P3251
P3251
P3251
P3251
P3251
Connector
P3251
P3251
Description
Auto on disabled
Auto on enabled
Power off
Power on
GTX 3X5 Transponder TSO Installation Manual
Connector Pinout Information
Pin I/O
21 I
42 I
61 I
62 I
20 --
41 --
39 O
60 I
Pin I/O
59 I
38 I
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