Ranco 2-stage temperature controller

[RichardMNixon]

I'm trying to wire-up a 2-stage ranco to my fridge and space heater, but having a nightmare getting the wires into the contacts. The videos I found are all for the one stage, and I was able to splice two wires together to get them into the contact. For the two stage though, I need to splice all 3 neutrals into one contact and I can't get them to fit for the life of me (especially because the extra set of contacts means less room in the box). I tried crimping them into a terminal with a blade connector, but the terminal doesn't fit inside the contact!

If I cap all 3 (12 gauge) together along with a 4th 12g wire and plug that one into the contact, will that work? It sounds like a bad idea to feed one wire into three but I guess only 2 of the three will be active at any given time?

Do I just need to find smaller terminals and do that? Is it a terrible idea to deform the terminal blade a bit with pliers so that it fits inside? Any other suggestions?

Thanks!

 

[day_trippr]

If you connect the line cord neutral lead to a duplex outlet (assuming you're using one) then add a separate wire from the same side of the duplex back to the Ranco's neutral terminal you won't even need a wire nut.

The only need for a neutral connection to the Ranco is for it's own internal power needs - which are trivial. The relays switch the hot side to the split duplex outlet (again, assuming you're using one) and the neutral return from the two loads should originate there. But if you're determined to use a nut on the neutral side there's no problem with that, either.

btw, the Ranco screw terminals operate by clamping the wire ends above the moving metal tang, not below it...

Cheers!

 

[RichardMNixon]

If you connect the line cord neutral lead to a duplex outlet (assuming you're using one) then add a separate wire from the same side of the duplex back to the Ranco's neutral terminal you won't even need a wire nut.

The only need for a neutral connection to the Ranco is for it's own internal power needs - which are trivial. The relays switch the hot side to the split duplex outlet (again, assuming you're using one) and the neutral return from the two loads should originate there. But if you're determined to use a nut on the neutral side there's no problem with that, either.

No outlet, I just have the plug and two female cords sticking out octopus-style. I managed to wire-nut all three neutrals together with a fourth wire and put that one in the "com" terminal on the Ranco. I have the hot wire from the wall nutted with three other wires, one goes to the "120" terminal, the other two to the "C" terminal on each stage. It seems to be working fine now, is this safe in the long run or do I need to change something?

btw, the Ranco screw terminals operate by clamping the wire ends above the moving metal tang, not below it...

Hmm... I'm not sure exactly how I did it, it was hard to see in them. Should it be impossible to do the wrong way or just wrong? I screwed them all the way counterclockwise, then inserted the wire, then tightened them clockwise.

Thanks for the help!

 

[day_trippr]

No outlet, I just have the plug and two female cords sticking out octopus-style. I managed to wire-nut all three neutrals together with a fourth wire and put that one in the "com" terminal on the Ranco. I have the hot wire from the wall nutted with three other wires, one goes to the "120" terminal, the other two to the "C" terminal on each stage. It seems to be working fine now, is this safe in the long run or do I need to change something?

As long as all four wire ends are tightly twisted together for 3-4 turns it should be quite safe.

Hmm... I'm not sure exactly how I did it, it was hard to see in them. Should it be impossible to do the wrong way or just wrong? I screwed them all the way counterclockwise, then inserted the wire, then tightened them clockwise.

Thanks for the help!

Clockwise to clamp the wire is correct, and if the wire was held tight you're good to go. I only mentioned that as there have been instances of folks turning the screws counter-clockwise and trying to clamp the wire to the top of the PC board, but that's definitely not how those terminals work...

Cheers!