Can you back-feed a GFCI breaker in a sub-panel?

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sw_ross

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Can you back-feed a GFCI breaker in a sub-panel and have it function as it's designed? Would it then GFCI protect the other circuits that were fed out of the sub-panel as a GFCI receptacle can protect the downstream receptacles?

Is it only designed to detect a fault to ground on the load side of the breaker?

Thanks for any feedback,
Sky
 
I seriously doubt it will work. It may even damage the breaker. Besides if forget which code section it will violate but there is a section that prohibits this when the breaker is labled Line and Load. since all GFCI breakers I have seen have lables " Load" this would be a issue.
 
I have honestly never tried it. Those things are just to dang expensive. I really doubt it though. At the very least it would not bet installed according to its instructions. At the worst you would be liable for any deaths or injuries resulting from the installation. You are anyway.

Back feeding the older GFCI receptacles would result in the (line to the load side) would result in the devices after it being protected but anything plugged into the GFCI would not be. Comparing oranges to tangerines.

Open your wallet, put on some PPE and let us know.
 
I doubt you'd ruin the GFCI, but you won't get any GFCI protection from it.

The GFCI breaker has line & load connections just like a receptacle. Wire them backwards, no protection.
 
480sparky said:
I doubt you'd ruin the GFCI, but you won't get any GFCI protection from it.

The GFCI breaker has line & load connections just like a receptacle. Wire them backwards, no protection.
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I tried this once with a GFCI to backfeed residential panel in a home under construction. The site was powered from a temp pole and I wanted to power an inside panel with GFCI protection. The contractors tools on occasion tripped the GFCI at the temp pole. The contractor kept complaining that he had to dig out the panel from the snow to reset the breaker. So in my infinite wisdom tried to move the GFCI breaker into a sub panel inside the home as much of the finish was complete. Well I backfed the breaker and it smoked it POOF done GONE...
I replaced the breaker and told the contractor not to use that tool and if so he'll need to go out into the snow and reset the GFCI as it was doing it's job.
 
The situation I'm dealing with is a sub-panel that is dedicated to feeding a hot-tub and it's related circuitry. The sub is located near the hot-tub, at the other end of the basement from the mechanical room where the main service panel is located. It's an older setup put together by a previous HO. The sub-panel is an old Federal Pacific that was red-flagged by a home inspector as being a fire hazard so the current HO wants it replaced. In the process it's become apparent that there is no GFCI protection for this hot-tub.

The circuits that the sub-panel feeds is the hot-tub heater, 2 pump motors (1 for the jets, and the other a circulating pump for the heater), and a control circuit.

I guess I'll just put the GFCI breaker in the main service panel that feeds the sub-panel, and back-feed a regular 2-pole 60a breaker (which will be the disconnect for the hot-tub) in the sub-panel. Currently the sub-panel is an MLO, so there is no single breaker acting as the disconnect. I assume the 6-switch rule doesn't apply to this situation and I need a single switch to act as the disconnect switch.

Thanks for any feedback,
Sky
 
If you have room to mount it, probably the easiest way to do this is install a two circuit load center, feed that with the old panel feed, then in turn re-feed the old (new) panel with the load side of the gfi breaker that was installed in the two circuit load center.
 
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My solution would be to mount a spa-pak .preferably a Square D or similar that has 2 additional spaces for breakers and also of course has its own gfci at 60 amp or 50 to protect the spa depending upon its needs. Use the other circuits for whatever. feed this with 60 from the main panel and your done.The 50 or 60 amp spa pak withe 2 pole gfi will power all the circuits you need for the spa and you will have either 2 or 4 cicuits depending on which breakers you use for other loads if needed.
 
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Why not put GFCI on supply side of feeder? (in your new panel)

Spa's have to have GFCI protection, but there is no requirement as to where the GFCI device is located.

For those that complain about having to go clear to the panel if it trips - How often do they trip unless there is a problem? Most of the times I have seen GFCI tripping in spa's is because heating element has failed and faulted to ground - the GFCI is doing what it is supposed to in this case.
 
stew said:
My solution would be to mount a spa-pak .preferably a Square D or similar that has 2 additional spaces for breakers and also of course has its own gfci at 60 amp or 50 to protect the spa depending upon its needs. Use the other circuits for whatever. feed this with 60 from the main panel and your done.The 50 or 60 amp spa pak withe 2 pole gfi will power all the circuits you need for the spa and you will have either 2 or 4 cicuits depending on which breakers you use for other loads if needed.
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Spa pak is the way to go, in my area they are ususally cheaper than 2pole GFCI breaker.
 
I never tried it, or have I?

I have run electric hoists that dump their braking regen back on the line on circuits protected with a GFCI. Nothing smoked
 
I've always wondered what the cut off point was for the regen from hoists. The hoist in question was about 3/4 or 1 HP on a 120 volt circuit. I never worried about that one.

But back before I knew better, I converted a 10 ton bridge crane from 250V DC to 480V AC power :ashamed:
 
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