GF Outlet Placement

jamiedolan

My last questions of the day. Thank you all for your kind help today, it has been another great day of learning these for you guys. Tommrow is going to be a working day, I hope to get a lot of EMT put in and wired up. The MWBC's are going to save me a lot of time. I just hope they work OK with Ground fault outlets on them, anyone know?

Does it matter where I put a Ground Fault outlet? Can I put it in the basement for a circuit elsewhere? My new hot tub room is fed power to the light, and it all splits out from there. The whole room, including the lights need GF protection per the NEC. So there is no easy way in the room to just put in an outlet that covers everything, since power starts at the light.

So could I put a GF outlet in the basement prior to this circuit going into the breaker box to protect it? Or should I dish out the $45 or so for a GF breaker?

Thanks
Jamie

Gigs

The power doesn't have to start at the light. I just did this to correct my mistake in not including a GFI in my basement circuits... I pulled a new wire and I'm feeing it from the other end, so I can use just one GFI outlet and still have my unprotected chest freezer single outlet (which is now at the beginning, was at the end).

So if you can just change where the circuit "starts" from, if it makes it easier on you.

jamiedolan

I understand it doesn't have to start at the lights, and could change it, It's just a couple hours of rewiring and the cost of the wire. If I could put a GF outlet on it in the basement, I would be done in 15 minutes.

I like the idea of the GF breakers, but they are about 4 to 5 times the cost of a GF outlet.

rgsgww

You should not have any problems with the gfcis on the mwbcs unless you do somthing like this

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jamiedolan

So you just pig tail the neutral prior to droping it to a room. So lets say my junction box in the attic has 2 hots in it, and one neutral. I can pig tail the neutral, and then run each hot with a neutral wire from my pig tial connection to there desitination, just like you would with a regular circuit.

Jamie

InPhase277

Yes, a MWBC is only a problem after the GFCI. Before it, the GFCI cannot know anyhow.

jamiedolan

I am sorry, I am still a bit confused on what your refering to as before and after the GFCI.

If I run a MWBC from a regular breaker to my kitchen, and then each hot and the neutral run to outlets on the kitchen couter for example, and I put a GFIC on each of those primary outlets, will these GFIC outlets have a problem?

Thanks
Jamie

chris75

Wildie

You do not require GFCI on each outlet. You only require one per circuit.
The GFCI is placed in the first location that the MWBC terminates.
The remaining outlets are wired down-stream from the GFCI.
Everything wired down-stream from a GFCI is protected.

Where I live, the code requires that kitchen outlets are to be supplied with two 15 amp circuits each. In this case, two pole, ground fault breakers would be required.

jwhite

Wildie, where do you live. In the US the national code requires two 20 amp circuits minimum for the kitchen counter top recs.

A two pole GFI breaker would work, or one could use two seperate circuits and put GFI recs at the begining of each circuit as suggested.

A seperate GFI rec at each outlet would simplify the wiring problem here, but would also be much more expensive in cost of parts.

I would suggest following Chris's excellent drawing.

__________________
Master Electrician

jamiedolan

Hi Chris;
Thanks very much for the drawing. I am very glad for the confirmation that I was thinking of the wiring for these properly. Thank You.

I was thinking that GF outlets work by watching for a differance in current from the hot and the neutral, and I was thinking that that could be an issue with a neutral that is shared. But now I realize that a GFIC outlet must only look forward, to itself and thing wired after it, and it must not care about what is going on, on the neutral before the neutral gets to it. I was thinking before that the GFIC outlet on circuit A. would have a problem with the recurrent that is being sent back on the neutral from circuit B. But the GFIC outlets must not care about what is going on before the power gets to them.

Thanks again, I am very glad to know this will work. In the basement with connecting the old circuits, I now have my first 4x4 box full, with 6 circuits in it, connected to the panel via 3/4" emt, on 3 double pole breakers. 3 - Neutrals, 6 hots, 1 ground wire.

I have to go get some more double pole breakers and hope to acomplish alot more this afternoon. I will get some photos poster later on.

Jamie

jamiedolan

Thank you. Now I understand you image. Thank you very much for your assistance.

Jamie

Wildie

I live in Ontario, Canada and the Ontario Electrical Safety code is used.
Kitchen's must have 3 split receptacles. These are fed from 2 pole/15 amp breakers on 14/3 NMD cable.
This provides 15 amps to each half of the receptacle.
Therefore a total of 60 amps is available in the kitchen area.
The use of 12 guage wire although legal is virtually unknown here.

The drawing shown by Chris would be considered illegal, unless it is fed by a 2 pole breaker!

chris75

Good Ol' USA!

rgsgww

Every mwbc in the usa is double pole.