Port Axlink NI2100

I'm not real familiar with those, but if they are Axlink, it's pretty much a standard thing. On your 4-wire Axlink buss, connect the ground, AXM and AXP wires only. Do not connect PWR. On your external supplies, connect the power + wire directly to the PWR connection, and parallel the power supply ground with the GND line that is already connected on the Axlink buss.

With Axlink, there are cable length limitations. Refer to the Tech Note "Axlink Wiring Considerations" (DL160) on the specifics. In essence, the total length of the Axlink cable can be no more than 3000 ft, if you are using proper Axlink cable. If you use CAT5/CAT6, it can be much less. Power distribution can also affect the total length of the cable. Total length refers to the combination of all legs of Axlink, not the farthest point.

All the advice about axlink wiring is great, But What is a AXB-TEMP? I've never heard of such a thing. But I've only been programming AMX for 20'ish years, maybe I've missed something.

Axlink boxes used to be like a Swiss Army knife. There was one for almost anything. I think these are temperature sensors ... but they also had a native X-10 controller once, and a variable DC voltage box, among other things. I kind of miss those days, you could integrate anything. Nowadays, stuff has to pretty much be designed for integration.