4-prong GFCI to Heating Element...I'm lost...

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

sleewok

Active Member
Joined
Mar 19, 2013
Messages
28
Reaction score
1
Hello all,

I've been reading, and reading, and reading...and I can't seem to wrap my head around exactly how I need to wire up my electric kettle. I've searched the forum and I've seen lots of diagrams. However, they all seem to be doing more than I need.

I'm trying to get this all setup so I don't kill myself...
I purchased a GFCI Spa Panel that is going into the main panel at my house. I have a 4 prong outlet connected to the spa panel. The 4 wire cable that I plug in (to the spa panel) will go to my "control box". The cable will be used to connect to a relay that would be connected to a 3 prong outlet (that I'll plug my heating element int).

I don't need 120v, as I'm powering my pot. with a separate power source.

So the question is what do I do with the 4 wires coming in to the panel (that will connect to a 3 prong outlet)? From what I gather I would run 1 hot wire to the relay (then out to hot on the outlet), and the other hot wire directly to the outlet. Can someone tell me what to do with the neutral and ground? I'm pretty sure that the ground (I should mention the ground doesn't have insulation) should go to the outlet (since I need to ground the kettle). In one thread there was a mention of just putting a wire nut on the neutral and taking the ground to the outlet.

Is this okay (as in it will allow the GFCI/ground protection to work properly)?

One other question. If I were to end up wiring directly to a 3 prong dryer outlet (rather than the main panel) using the wiring in the attached image will I get the same level of protection as I would if connected to the main panel?

power-panel-6.jpg


Thanks ahead of time! I hope this will bring me some peace of mind.

- Lee
 
In your control panel, you need a DPST or DPDT relay. The relay should switch both hot wires.

If the relay has a 220V coil you don't need to run a neutral wire to the control panel. If the relay has a 110V coil you will need to run a neutral wire just for the coil.

You need to run a ground wire to the control panel to ground the panel itself (assuming it's a metal box).

I don't know the answer to your question about running power from a 30A dryer receptacle.

P-J has made lots of useful wiring diagrams for different types of panel, it might help you to study one that looks close to your plans and ask questions about specific modifications that you want to make.
 
Everything will work correctly for your 220v circuits to your elements if you omit the neutral wire. You have a few different options. You could use a 3-prong outlet in the spa panel and not bring the neutral out of the breaker. You could use the existing 4-prong outlet and not bring the neutral out of the spa panel breaker. I would do that, and run 4-wire cable (H-H-N-G) from the spa panel to the control panel. You would not have anything connected to the neutral in the control panel, and since you did not bring the neutral out of the spa panel there is nothing else you would need to do. The advantage here is that you would not have to change out that cable if you ever wanted to use the neutral.

Backing up a bit, are you putting a new breaker in your main panel and wiring that to an outlet? If that is the case, by all means run 4-wire out of that breaker to your spa panel. You would wire the spa panel differently, per https://www.homebrewtalk.com/f170/wiring-spa-breakout-box-anyone-got-pictures-360313/. You can still omit running the neutral out of the spa panel breaker, but now you have the best solution if you ever want to use the neutral to derive 120v.

And by all means ground everything properly. And take alien's suggestion about a mechanical contactor to cut off both legs of the 220v circuit. You want to switch that so that when the switch is off you know the element is off.
 
Hey guys, thanks for such a quick response. This is very helpful information. The diagram I posted is from PJ, so I'm guessing it is legit.

@jeffmeh If I do connect directly to the main panel I'll be installing a breaker. I would run 4 wires out from that. What you say makes sense.

With regards to a DPDT relay, could I just use a 30A 2-pole toggle switch? I have this exact one: http://www.menards.com/main/electri...-pole-single-pole-switch/p-1402907-c-6324.htm

Thanks again!
 
...@jeffmeh If I do connect directly to the main panel I'll be installing a breaker. I would run 4 wires out from that. What you say makes sense.....
If you run two hots, a neutral, and a ground from your main to the spa panel, keep the neutral and ground separate in the spa panel. Like the Post#2 photo in the thread that jeffmeh linked above. NOT like the photo you posted in this thread.
 
If you run two hots, a neutral, and a ground from your main to the spa panel, keep the neutral and ground separate in the spa panel. Like the Post#2 photo in the thread that jeffmeh linked above. NOT like the photo you posted in this thread.

+1 on this.
 
Hey guys,

I wanted to thank you again. I got everything installed and it works great. We did a ground fault test (crossed the hot+ground) and the GFCI triggered as well as the breaker (on the main panel). I'm obviously still alive :). I did a multi-meter test with the switch and it works as expected. I would not have this setup properly without your help. THANK YOU!

- Lee
 
Back
Top