XR Expansion SPDT 32-Relay Controller not responding


I am using an “ProXR Industrial Relay Controller Board 32-Channel SPDT + UXP Expansion Port” with a quantity of 3 “XR Expansion SPDT 32-Relay Controllers”. I am also using the RS-485 Serial Communications Module.

I have an issue where the last expansion board in my chain isn’t responding to any commands. All others are working fine. I am also using the 6″ XR Expansion Cable that is provided on every unit.

Any ideas on what could be the issue here?


Hi Dane,

Sometimes it’s possible for one of the driver chips on the board to become damaged. Try rearranging the boards in the chain to see if the issue is still with the same bank of relays, also check to see if relays after that bank still function.

Let me know what you find.

Thank you,
Travis Elliott

I did a few tests rearranging the order of the boards.
Looks like the expansion out port of the previous board is not working.
I can just move this one to the end of the chain and everything should work out for me.