Wiring Advice, 240v 3 Prong, Use Neutral as GND?

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SirMontalbon

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I'm upgrading from propane to electric and have become confused regarding using neutral as a ground.

My outlet is 3-pronged with hot red, hot black, and neutral white. Reading in terms of grounding, I've read don't use neutral as ground because is dumps stray current to the body of the kettle and won't trip the breaker until you touch it and the shock through your body flips the breaker. Having no ground at all seems even more sketchy.

My setup is straight forward: outlet to a switch, switch to a temp controller, temp controller to element. That said, which diagram should I follow, or are they both wrong?

Thanks in advance for your advice!

 

doug293cz

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They are both "wrong." You need to add GFCI (ground fault circuit interrupter) protection in order to prevent shock hazards. The top drawing is closer to being correct. I have added a yellow ellipse to show where in the circuit the GFCI protection should be added. The easiest way to do this is to add what is known as a "Spa Panel," which can be purchased at a big box hardware store. The spa panel allows you to create a ground from the original neutral in a way that will allow detection of leakage current (the source of any shocks), and trip the breaker in the spa panel if there is any leakage. There is a thread in the "Electric Brewing" forum that explains how to do this.

Where to add spa panel.png

Brew on :mug:
 
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SirMontalbon

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I did some more reading in the spa panel thread and came up with this diagram:



Any better?
 
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New concern...

I installed my new spa panel and wired it up, along with finishing up the wiring and build on my kettle. Tested it out and took some boil off measurements over the course of a few hours yesterday, and everything worked great!

Now, onto my concern... I gave the "Test" button on my GFI outlet a, ahem... test, and nothing! The breaker didn't break, and the kettle stayed powered. Did I miss something in my research? Is the 3-prong wiring somehow keeping the test button from working properly but I still have GFI (my gut instinct says no), or did I get a bunk GFI and need to return it for another?

Thanks in advance for your advice!
 

doug293cz

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New concern...

I installed my new spa panel and wired it up, along with finishing up the wiring and build on my kettle. Tested it out and took some boil off measurements over the course of a few hours yesterday, and everything worked great!

Now, onto my concern... I gave the "Test" button on my GFI outlet a, ahem... test, and nothing! The breaker didn't break, and the kettle stayed powered. Did I miss something in my research? Is the 3-prong wiring somehow keeping the test button from working properly but I still have GFI (my gut instinct says no), or did I get a bunk GFI and need to return it for another?

Thanks in advance for your advice!
If the test button does not trip the GFCI breaker, then you do not have GFCI protection. The test button works by creating a low current grounding path from one of the hot lines. This is the type of fault that the GFCI is designed to protect against. (The actual fault you would be worried about is a current path from hot to ground that goes thru you!)

Either the GFCI is faulty, or the spa panel is not wired correctly. Can you post clear pictures of the wiring inside your spa panels. Multiple angles are helpful, since some routing can be obscured at some angles and not others.

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I did some more reading in the spa panel thread and came up with this diagram:



Any better?
It's correct, but you'd be better off not running the GND from your brewery to a neutral. Not likely to be an issue, but if there are any other 120V devices on that circuit, the neutral will have current running on it and it's possible that the GND of your brewery could be elevated by I*R voltages. For example, if you had a 1A 120V device on that same circuit, and the resistance of the wire and connections between your dryer neutral and the grounding rod near your breaker box was 10 ohms, then your brewery ground becomes 10VAC.

Anyway, it's a minor thing, but if you could find a real safety ground to bond your pots and stuff too, you'd be better off.
 
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SirMontalbon

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Here are the pics of my spa panel and control panel. I retained the 240V switch in the control panel, which is not reflected in my last wiring diagram. The spa panel is fed by an extension cord in my storage room that plugs into a dryer receptacle. From the receptacle, it is a straight run to a 30A non GFI breaker in my main panel.

The control panel's bottom wiring input is the input from the spa panel. The wiring going out the top knockout is to the element and is grounded to the kettle.

















As long as the wire to the controller is rated for 60A, it's OK. It might not be, though, so probably good you brought it up :mug:
The spa panel feed is an extension cord that plugs into a dryer receptacle in my storage room. That receptacle is a straight feed to a 30A non GFI breaker in my main panel box. My understanding of using a spa panel is that the spa panel will cover your GFI, and the main panel breaker covers current monitoring duties. Is that correct?
 
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SirMontalbon

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It's correct, but you'd be better off not running the GND from your brewery to a neutral. Not likely to be an issue, but if there are any other 120V devices on that circuit, the neutral will have current running on it and it's possible that the GND of your brewery could be elevated by I*R voltages. For example, if you had a 1A 120V device on that same circuit, and the resistance of the wire and connections between your dryer neutral and the grounding rod near your breaker box was 10 ohms, then your brewery ground becomes 10VAC.

Anyway, it's a minor thing, but if you could find a real safety ground to bond your pots and stuff too, you'd be better off.
I'm running a separate 120V circuit for my pump, though this is a good point should I decide to add that in the future (which has crossed my mind).
 
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The spa panel feed is an extension cord that plugs into a dryer receptacle in my storage room. That receptacle is a straight feed to a 30A non GFI breaker in my main panel box. My understanding of using a spa panel is that the spa panel will cover your GFI, and the main panel breaker covers current monitoring duties. Is that correct?
Yep. You're right. No problem there.
 

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Here are the pics of my spa panel and control panel. I retained the 240V switch in the control panel, which is not reflected in my last wiring diagram. The spa panel is fed by an extension cord in my storage room that plugs into a dryer receptacle. From the receptacle, it is a straight run to a 30A non GFI breaker in my main panel.

The control panel's bottom wiring input is the input from the spa panel. The wiring going out the top knockout is to the element and is grounded to the kettle.



















The spa panel feed is an extension cord that plugs into a dryer receptacle in my storage room. That receptacle is a straight feed to a 30A non GFI breaker in my main panel box. My understanding of using a spa panel is that the spa panel will cover your GFI, and the main panel breaker covers current monitoring duties. Is that correct?
IM NOT AN ELECTRICIAN
But have the exact same setup as you. Mine only uses one bus bar as a ground. Your using both with a jumper.I remember when setting it up the white GFI wire had to be moved.

My setup:
Power TO spa panel: Two hots to main ports,Ground to ground bar
Power FROM spa panel to controller: two hots to ports on breaker,ground to bus bar.
White wire one breaker(looks like where yours is) To bus bar.
SO three grounds on one bus bar and nothing on the other one.
I called the spa panel company and sort of remember him saying the GFI needs to be grounded.
FEEL FREE TO TRIPLE CHECK but I would say that's your issue..let me know if it works...It should because mine works perfect.
 

JONNYROTTEN

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IM NOT AN ELECTRICIAN
But have the exact same setup as you. Mine only uses one bus bar as a ground. Your using both with a jumper.I remember when setting it up the white GFI wire had to be moved.

My setup:
Power TO spa panel: Two hots to main ports,Ground to ground bar
Power FROM spa panel to controller: two hots to ports on breaker,ground to bus bar.
White wire on breaker(looks like where yours is) To ground bus bar.
SO three grounds on one bus bar and nothing on the other one.
I called the spa panel company and sort of remember him saying the GFI needs to be grounded.
So basically just eliminate the cream color jumber and move the two white wires to the bar with the green wire and abandon that bar.
FEEL FREE TO TRIPLE CHECK but I would say that's your issue..let me know if it works...It should because mine works perfect.
EDIT: It looks like both bars are ground bars so my info is most likely useless :D. Then again if there both grounds why use both bars with a jumber and not just one??? Possibly a bad GFI breaker?? I be watching to see what the problem turns out to be.
 

doug293cz

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Here are the pics of my spa panel and control panel. I retained the 240V switch in the control panel, which is not reflected in my last wiring diagram. The spa panel is fed by an extension cord in my storage room that plugs into a dryer receptacle. From the receptacle, it is a straight run to a 30A non GFI breaker in my main panel.

The control panel's bottom wiring input is the input from the spa panel. The wiring going out the top knockout is to the element and is grounded to the kettle.



















The spa panel feed is an extension cord that plugs into a dryer receptacle in my storage room. That receptacle is a straight feed to a 30A non GFI breaker in my main panel box. My understanding of using a spa panel is that the spa panel will cover your GFI, and the main panel breaker covers current monitoring duties. Is that correct?
I don't see anything wrong with the way the spa panel is wired. The "Test" button should work. (If the neutral pigtail wasn't connected to the incoming neutral, then the test button wouldn't work.)

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doug293cz

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It's correct, but you'd be better off not running the GND from your brewery to a neutral. Not likely to be an issue, but if there are any other 120V devices on that circuit, the neutral will have current running on it and it's possible that the GND of your brewery could be elevated by I*R voltages. For example, if you had a 1A 120V device on that same circuit, and the resistance of the wire and connections between your dryer neutral and the grounding rod near your breaker box was 10 ohms, then your brewery ground becomes 10VAC.

Anyway, it's a minor thing, but if you could find a real safety ground to bond your pots and stuff too, you'd be better off.
I can see where this could be a concern if the dryer outlet was not the only outlet on the circuit from the main panel. But wouldn't that be an extremely unlikely scenario? To be safe the OP could get an outlet tester, shut off the dryer outlet breaker, and then test every outlet and light switch in the house. If any don't work with the dryer breaker off, then he has an issue.

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I can see where this could be a concern if the dryer outlet was not the only outlet on the circuit from the main panel. But wouldn't that be an extremely unlikely scenario? To be safe the OP could get an outlet tester, shut off the dryer outlet breaker, and then test every outlet and light switch in the house. If any don't work with the dryer breaker off, then he has an issue.

Brew on :mug:
Yea, I know, pretty dumb comment (seriously). But I did have this toaster oven once...
 
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SirMontalbon

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Good news is, the dryer outlet is only 6ft from the main panel and I can see the entire run, so I have visual confirmation that there is nothing else on that circuit. Hope that helps.
 
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Point taken.

I have access to the main panel and my multimeter. I would imagine that killing main power and removing the main panel cover to check for continuity against all circuits would be easier and more thorough than finding and testing every single outlet in my house with the dryer breaker flipped. Would you agree?
 
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There's about a 100% chance that the dryer is the only outlet on that ckt. Unless, of course, a brewer or welder lived there before you :) I wouldn't bother. My comments were sort of academic, not really useful. I probably should learn to keep my yap closed sometimes :)
 
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Ok, so I'm a little confused as to which way to go here. I opened my main panel and further visually confirmed the dryer outlet is on its own breaker and no continuity exist between any other circuit.

A previous comment mentioned I should decouple the neutral and ground bars in the spa panel and run a ground to a true ground in the main panel, but I traced the neutral/ground wire coming in the spa panel back to the neutral/ground bus in the main panel. Isn't that the same thing?

Or is it possible I got a bad breaker? Is there anyway to test the GFI itself?
 

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Ok, so I'm a little confused as to which way to go here. I opened my main panel and further visually confirmed the dryer outlet is on its own breaker and no continuity exist between any other circuit.

A previous comment mentioned I should decouple the neutral and ground bars in the spa panel and run a ground to a true ground in the main panel, but I traced the neutral/ground wire coming in the spa panel back to the neutral/ground bus in the main panel. Isn't that the same thing?

Or is it possible I got a bad breaker? Is there anyway to test the GFI itself?
There is definitely a way to test the GFI because I did it. Cant remember for the life of me how I did it. A simple call to the manufacture technical support would probably answer all your spa panel questions/issues at this point
 
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An update for closure and posterity; the breaker and its subsequent replacement wete defective. The seller on ebay refunded my money and let me keep the panel and breaker. I contacted GE and they overnighted a brand new replacement breaker free of charge. All now works as it should.

Thanks for everyone's help.
 
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