Properly wiring a GFCI Breaker in a Subpanel

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  #1  
Old 03-27-13, 09:18 AM
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Properly wiring a GFCI Breaker in a Subpanel

I'm building an Electrical Brewery so I need to protect myself from any mishaps. The current setup has the Neutral bar and the ground bar common. I believe to properly wire a GFCI Breaker the Neutral bar must be isolated from the ground bar and enclosure. Where I currently have all the neutral/white wires I don't think i can isolate that bar. So I'll need to isolate the small ground bar in the upper right corner and run the white wires to that and then run all the bare copper wires where the white wires are now. Please advise if i'm correct or what else I need to do. I've attached pictures of the sub-panel, GFCI and the isolation kit. The actual GFCI breaker I'm installing is a DP 20A HOM220GFI and will replace the DP 20A std breaker on the right.

Edit, crap I can't be right with above. The neutral wire from my feeder is on the neutral bar now. How do I isolate the neutral bar? if i put the grounds there i can't accomplish what I want. I don't know how to set up this panel.
 
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Old 03-27-13, 09:40 AM
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Welcome to the forums!

I believe to properly wire a GFCI Breaker the Neutral bar must be isolated from the ground bar and enclosure.
Isolated neutrals and bonded grounds are not necessary for GFCI breakers to work properly. They work just fine in common-bonded main distribution panels.

Where I currently have all the neutral/white wires I don't think i can isolate that bar. So I'll need to isolate the small ground bar in the upper right corner and run the white wires to that and then run all the bare copper wires where the white wires are now. Please advise if i'm correct or what else I need to do.
You need to isolate the neutrals because this is a subpanel. Remove any ground wires from the bar that the feeder neutral is connected to and test for continuity between that bar and the box. If you find continuity, look for the screw or strap that is bonding them together, remove it, and test again. Once you have that bar isolated, connect the neutrals to it and the grounds to the small bar in the upper right corner.

I've attached pictures of the sub-panel, GFCI and the isolation kit. The actual GFCI breaker I'm installing is a DP 20A HOM220GFI and will replace the DP 20A std breaker on the right.
Thank you for the pictures. Why are you installing a 2-pole 240V GFCI breaker? What will it be protecting?

The neutral wire from my feeder is on the neutral bar now. How do I isolate the neutral bar?
See above. It may already be isolated.
 
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Old 03-27-13, 09:52 AM
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I believe to properly wire a GFCI Breaker the Neutral bar must be isolated from the ground bar and enclosure.
No, that refers to how to install a subpanel. Either way will work for a GFCI. If that is a subpanel the neutral needs to be isolated and that ground wire on the neutral bar needs to be moved to the ground bar.

So I'll need to isolate the small ground bar in the upper right corner and run the white wires to that
No. The big bar is your neutral and will be isolated when you remove the grounding screw.

How do I isolate the neutral bar?
Remove the bonding screw.

The above assumes that is a subpanel. If it isn't the answers change.

Echo... echo.
 
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Old 03-27-13, 06:17 PM
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Edit, crap I can't be right with above. The neutral wire from my feeder is on the neutral bar now. How do I isolate the neutral bar? if i put the grounds there i can't accomplish what I want. I don't know how to set up this panel.
Just making a stab here, but I don't see the problem. Remove the bonding screw and the neutral bar is isolated from ground. Could it be you are confused on where to land the neutral conductor from the 12-3 NM B cable that will be fed by the 20A GFCI breaker? All 3 insulated wires (blk, red, wht) are landed on the GFCI breaker. Only the white pigtail on the GFCI breaker lands on the panel neutral bar.
 
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Old 03-31-13, 02:50 PM
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I can't find any grounding screw or Bonding screw. The one screw on the far right of the Neutral bar has a strange head and I'm assuming that it's not supposed to be removed. It's not allen, hex, phillips or square. It looks to be hex but it is so shallow I can't get anything to grip it or seat properly to remove it. The one bare wire that looks like it's in the Neutral bar isn't, it comes out of the sheathing and rounds it's way to the ground bar in the upper right corner.
The Neutral bar has continuity to the box/ground bar. The third hole left from the right end of the Neu bar has nothing in it. But it looks like I can see all the way through to the plywood that the panel is mounted on. Don't know the function of this hole. I can see the panel has a factory hump on the back of the panel from that hole. Like maybe it would be where it would be grounded to the panel.
 
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Old 03-31-13, 03:37 PM
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On your neutral bar, the third hole from the right, there is no screw, right? That is where your bonding screw would go if it were a primary panel. You will find that green screw in a plastic bag inside the panel somewhere. Don't use it and the neutral bar is isolated.
 
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Old 03-31-13, 04:05 PM
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Hi Chandler

Yup the third hole from the right is empty but the Neutral Bar is still common with the panel. When I put my meter on logic the neutral bar beeps when shorting the panel or the ground bar. There are only white neutral wires from the attached breakers in the neutral bar. Could the total continuity be coming from my main panel in the basement. I had an electrician put a 40A breaker in my QO panel in the basement to supply power to this homeline sub panel in my garage. I tend to think not. would no mater what I had, i should be able to isolate the neutral bar from the panel.
BTW my 40A breaker in the basement is off so I don't get any surprises.
 
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Old 03-31-13, 04:34 PM
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You can't measure with the white wires connected to the neutral bar because neutral and ground are connected at the main panel.
 
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Old 03-31-13, 04:37 PM
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OK, i'll try that. I'll pull all the white wires out of the neutral bar and check and see if it's isolated. Thanks
 
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Old 03-31-13, 04:52 PM
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OK were getting somewhere, not sure where but my logic beeper is finally silent. First I took all the breaker white wires out and it still had continuity. So I took out the large white wire from the basement breaker and now I can experience Isolation from the panel.
So what does this tell me? Do I just swap out the std 20A breaker and put in the GFCI 20A breaker and it's good to go or do I need to do something in the basement?
I think the coiled up white wire goes to the neutral bar and the white wire that goes to the 20A 240v receptacle goes to the GFCI breaker instead of the neutral bar. Please don't holler too loud if I'm wrong I'm an old man and I might faint. LOL
 
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Old 03-31-13, 05:28 PM
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I think the coiled up white wire goes to the neutral bar and the white wire that goes to the 20A 240v receptacle goes to the GFCI breaker instead of the neutral bar.
Bingo! That is correct.
 
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Old 03-31-13, 07:07 PM
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Thanks Ray.

I take it that it doesn't matter that the panel and the neutral bar will read common because of the wiring from the basement QO panel? I don't need to do anything else?
 
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Old 03-31-13, 07:51 PM
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Your good to go.

.
 
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Old 03-31-13, 07:53 PM
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I take it that it doesn't matter that the panel and the neutral bar will read common because of the wiring from the basement QO panel?
That's right.

I don't need to do anything else?
So long as you've tested with all of the wires off and found that you do have continuity between the added ground bar and the box, and you install the GFCI breaker the way you described doing it, you should be good to go.

But I'm still curious.
Originally Posted by Nashkat1
Why are you installing a 2-pole 240V GFCI breaker? What will it be protecting?
 
  #15  
Old 03-31-13, 07:54 PM
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Oh crap,

Now what? When this breaker was originally wired up the white wire wasn't supposed to coil around and into the bottom of the breaker but only a short jaunt over and down into the Neutral bar. My white wire isn't long enough for the journey. It's in a conduit that has tooo many twists to allow any pulling of the wire through the conduit. is there anyway I can splice about 12" on the end of the white wire to loop around to the bottom of the GFCI Breaker?
 
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Old 03-31-13, 08:12 PM
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is there anyway I can splice about 12" on the end of the white wire to loop around to the bottom of the GFCI Breaker?
Sure. Just use wire the same gauge.

Are you going to answer my question about the 2-pole breaker?
 
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Old 03-31-13, 08:15 PM
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But I'm still curious.
Quote Originally Posted by Nashkat1
Why are you installing a 2-pole 240V GFCI breaker? What will it be protecting?

Read more: http://www.doityourself.com/forum/ne...#ixzz2PB5bpSGt

I'm building an Electric Beer Brewing Panel that will control two 3500 Watt water heater elements in both the Boil Kettle and the Hot Liquor Tank via PID's and RTD temperature probes. Also two food grade liquid pumps, pump the hot liquids to various vessels. It's common practice and normal procedure to protect these panels (ie, me) due to the liquids involved.

They heavily stress the GFCI protection in their instructions.
Electric Brewery
 

Last edited by Clare Valley; 03-31-13 at 08:39 PM.
  #18  
Old 03-31-13, 08:19 PM
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Are you going to answer my question about the 2-pole breaker?


Sorry I was a little slow as I was trying to learn how to wrap the quotes like you guys do.
 
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Old 03-31-13, 08:22 PM
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is there anyway I can splice about 12" on the end of the white wire to loop around to the bottom of the GFCI Breaker?
Sure. Just use wire the same gauge.
What's the best procedure for splicing the wires? Twist On Wire nuts?
 
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Old 03-31-13, 08:57 PM
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Yes wire nuts are fine.

.
 
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Old 03-31-13, 09:46 PM
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I'm building an Electric Beer Brewing Panel that will control...
and that panel needs to be supplied with 240V power?
 
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Old 03-31-13, 09:48 PM
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What's the best procedure for splicing the wires?
Use pliers to twist the wires together with at least three twists, clockwise. Trim the end if needed. Hand-twist a wire nut on to protect the splice.
 
  #23  
Old 04-01-13, 12:42 AM
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and that panel needs to be supplied with 240V power?
If the panel was 120V and 15A the max heating element would be 1500w, not enough to make a rolling boil.
If it was 120V 20A the max is 2000w, still not enough.
240V 20A can power 3500w and with 6 gal it will work and boil the wort.
Most of the panel builders use 20gal kettles and make 10 to 12 gal batches and they use 240V 30A to power 5500w elements.
120V just isn't enough power to boil the wort sufficiently. If it would boil the wort it would be too slow and that isn't good as air contaminants would have too much time to take hold and leave off flavors.

Use pliers to twist the wires together with at least three twists, clockwise. Trim the end if needed. Hand-twist a wire nut on to protect the splice.
Thanks for the tip. My 12 GA wire is stranded from the bulk rolls at Lowes. Will that present any problems splicing with the solid 12 GA wire? I could I suppose take some 12/3 w/Ground apart and splice that in if you think that would be better.

You can see the plans for the panel here

Thanks for all your help and sorry I missed the question from earlier.
 
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Old 04-01-13, 11:15 AM
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240V 20A can power 3500w and with 6 gal it will work and boil the wort.
OK, thanks.

My 12 GA wire is stranded from the bulk rolls at Lowes. Will that present any problems splicing with the solid 12 GA wire?
It should be fine. I spread stranded conductors into a brush shape, lay that next to ant solid conductors and just twist a wire nut on when I need to splice those together.
 
  #25  
Old 04-01-13, 02:20 PM
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It should be fine. I spread stranded conductors into a brush shape, lay that next to ant solid conductors and just twist a wire nut on when I need to splice those together.
Thanks Nashkat1 That's what I'll do.
 
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