Im Planing on doing some thing similar. My BCS is located at my brewery in the garage and my room where I ferment is about a 20' away to run wires along the wall to get to the room. My plan is to use a DIGI16 expansion board in the fermentation room to control heating and cooling of the fermenters. the problem with this is that the DIGI16 does not support more temp probes. So what I'm going to to is put in four switches or soem type of selector switch in my control panel that will let me switch from the probes monitoring the brewing process and the probes monitoring the fermentation process.
In the fermentation room I'll put in XLR disconnects for the temp probes, and connect them to the selector switch with a CAT6 like cable that has 8 wires. 4 for the temp probes, 1 for power, 1 for ground ,1 EO, and one of E1.
There the DIGI can control 8SSR's to power heating and cooling to up to 4 fermenters.
I still have not worked out all the details, Im still in the planing phase. I have to get the Glycol system Up and running first before I move on to this one. But the wheels are turning.
Curious to see how others have done it. Jon W might be a good person to contact about it, I think he has some thing like this set up. It my be on the ECC forum.
Something like this