CAT-5 Control Wiring

[jmdenmark]

Quick question before I embark on this wiring. If I follow some of the previous posts, CAT-5 cable is fine for the +5VDC control wiring both for temperature probes and SSRs.

The plan for my HERMS location is to have a 30A/220V outlet (5500W element) controlled by 2 D1240 SSRs, two 15A/110V outlets for pumps controlled by two more D1240s (overkill but I have them available) and two temperature probes all located in one spot.

If I follow this correctly, I could just run one CAT-5 cable from the BCS location (dry and comfortable) to the HERMS location (wet and cold) to control all this with:
4 wires for the SSRs (2 on Out0, 1 on Out1 and 1 on Out2)
1 wire for SSR common GND
2 wires for temperature probes to Temp0 and Temp1 (on 2.5mm jack plugs or some similar connector)
1 wire for probes common GND (presumably could share GND but cleaner this way)

Does this sound right? Am I missing something?

If so, this would be a much cleaner setup than colocating all the SSRs near the BCS in a project box and distributing the AC lines out from there.

Thanks for your comments,

Jim.

[ECC]

Yeah, that sounds reasonable.

I don't think you gain anything by using 2 wires on Out0. If it were me, I'd use the extra wire to give each Temp it's own ground. Not that they need them electrically.. Cat-5 uses twisted pairs, so each Temp having its own unique ground in its twisted pair might give them slightly better noise immunity.. But that suggestion is purely speculative, I doubt that you would see a difference either way.

Let us know how it works!
Cheers

[jmdenmark]

Don't I need two wires on Out0 to trigger both SSRs (each 110V leg of the 220V circuit) simultaneously?

I guess if I splice the cable at the SSR end and wire them in parallel as it will be the same current as two individual wires split at the BCS end. Answered my own question I think...