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G3X GTX23 interconnect error

NTex

Well Known Member
All,

Can someone double-check interconnects for me?

The G3X installation manual , Rev AD, page 25-80, "LRU Pinouts for the GTX 23" states:

"RS-232 input channel 1 is used to receive pressure altitude and control commands, and to provide status,
TIS-A traffic, and other data. RS-232 output channel 1 provides unit status and TIS data. RS-232 channel
1 input and output are also used for software upgrades. RS-232 port channel 1 on the GTX should be
connected to the channel 1 RS-232 port on ADAHRS 1.
"

But, page 25-57 "LRU Pinouts for the GSU 25" states:

2 Channels of RS-232 RX, and 3 Channels of RS-232 TX data.
RS-232 1: Can optionally be connected to a GDU display to provide a redundant path for attitude data.
Also used to configure a GSU 25 as ADAHRS #3.
RS-232 2: Transmits data to the GMU 22.
RS-232 3: Connects to a GTX transponder to provide pressure altitude data and remote transponder
control. Transponder should only be connected to ADAHRS 1 (not 2 or 3).

The GTX 23 installation manual, revision G page 4-5 doesn't specify which port to use on the controlling device (G3X in my case) -- which makes sense.

So should the GTX connect to Channel 3 or Channel 1 of the GSU 25? I thought that Channel 1 was the backup RS232 path for the GDU for a CAN failure.

Thanks,
Chris
 
You connect the GSU25 RS232#3 to the GTX23ES RS232#1

P252.9 to J2301.22
P252.10 to J2301.23
P252.11 to J2301.43 (gnd)
 
All,

Can someone double-check interconnects for me?

The G3X installation manual , Rev AD, page 25-80, "LRU Pinouts for the GTX 23" states:

"RS-232 input channel 1 is used to receive pressure altitude and control commands, and to provide status,
TIS-A traffic, and other data. RS-232 output channel 1 provides unit status and TIS data. RS-232 channel
1 input and output are also used for software upgrades. RS-232 port channel 1 on the GTX should be
connected to the channel 1 RS-232 port on ADAHRS 1.
"

But, page 25-57 "LRU Pinouts for the GSU 25" states:

2 Channels of RS-232 RX, and 3 Channels of RS-232 TX data.
RS-232 1: Can optionally be connected to a GDU display to provide a redundant path for attitude data.
Also used to configure a GSU 25 as ADAHRS #3.
RS-232 2: Transmits data to the GMU 22.
RS-232 3: Connects to a GTX transponder to provide pressure altitude data and remote transponder
control. Transponder should only be connected to ADAHRS 1 (not 2 or 3).

The GTX 23 installation manual, revision G page 4-5 doesn't specify which port to use on the controlling device (G3X in my case) -- which makes sense.

So should the GTX connect to Channel 3 or Channel 1 of the GSU 25? I thought that Channel 1 was the backup RS232 path for the GDU for a CAN failure.

Thanks,
Chris

Hello Chris,

Page 26-22 of the Rev. AD G3X/G3X Touch Installation manual shows you exactly how to wire the GSU 25 to the GTX 23ES.

Thanks,
Steve
 
Hello Chris,

Page 26-22 of the Rev. AD G3X/G3X Touch Installation manual shows you exactly how to wire the GSU 25 to the GTX 23ES.

Thanks,
Steve

Thanks to Steve and N96TJ for confirming the writeups are incorrect and the drawing is right!
 
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