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Do GFCI receptacles require dedicated neutral?


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#1 vbar

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Posted 14 June 2011 - 12:05 AM

Suppose we have two GFCI receptacles. The first is on Circuit 1 and the other is on Circuit 3. They are both fed from the same panel. They both share a neutral wire.
Am I correct to think that if both receptacles are in use at the same time the first receptacle will trip since the current differential will be different, due to the shared neutral?



#2 wilheldp_PE

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Posted 14 June 2011 - 02:17 AM

Are you talking about a ground or a neutral. Each GFCI does require a dedicated hot and neutral, but you can daisy-chain the ground. The way you would normally install two GFCI protected outlets is to put the GFCI closest to the panel, then daisy-chain a regular outlet off of it. If you put another GFCI downstream of a GFCI, it will not work correctly.

#3 vbar

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Posted 14 June 2011 - 04:22 PM

QUOTE (wilheldp_PE @ Jun 13 2011, 07:17 PM) <{POST_SNAPBACK}>
Are you talking about a ground or a neutral. Each GFCI does require a dedicated hot and neutral, but you can daisy-chain the ground. The way you would normally install two GFCI protected outlets is to put the GFCI closest to the panel, then daisy-chain a regular outlet off of it. If you put another GFCI downstream of a GFCI, it will not work correctly.


My question was about the neutral. And you answered it by saying "Each GFCI does require a dedicated hot and neutral".

#4 friend_northeast

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Posted 11 January 2012 - 08:55 PM

A shared neutral is allowed by code but it better be fed off a two pole breaker.

#5 MA_PE

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Posted 11 January 2012 - 09:28 PM


QUOTE (wilheldp_PE @ Jun 13 2011, 07:17 PM)
Are you talking about a ground or a neutral. Each GFCI does require a dedicated hot and neutral, but you can daisy-chain the ground. The way you would normally install two GFCI protected outlets is to put the GFCI closest to the panel, then daisy-chain a regular outlet off of it. If you put another GFCI downstream of a GFCI, it will not work correctly.


My question was about the neutral. And you answered it by saying "Each GFCI does require a dedicated hot and neutral".

If I understand this correctly (I'm not an electrical guy) if one installs a GFCI on given circuit, then any subsequent regular outlets further away from the panel and on the same circuit are also protected. correct?

#6 knd107

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Posted 11 January 2012 - 09:49 PM

Yes, that is correct. If the first recept is GFCI then it will protect the downstream recepts.


Suppose we have two GFCI receptacles. The first is on Circuit 1 and the other is on Circuit 3. They are both fed from the same panel. They both share a neutral wire.
Am I correct to think that if both receptacles are in use at the same time the first receptacle will trip since the current differential will be different, due to the shared neutral?


You probably don't want to share the neutral between 2 circuits normally. Also, GFCI works by sensing the returning current on the Line and Neutral so it would most likely trip both devices due to a single fault.

#7 USFishin

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Posted 19 June 2012 - 12:47 PM



QUOTE (wilheldp_PE @ Jun 13 2011, 07:17 PM)
Are you talking about a ground or a neutral. Each GFCI does require a dedicated hot and neutral, but you can daisy-chain the ground. The way you would normally install two GFCI protected outlets is to put the GFCI closest to the panel, then daisy-chain a regular outlet off of it. If you put another GFCI downstream of a GFCI, it will not work correctly.


My question was about the neutral. And you answered it by saying "Each GFCI does require a dedicated hot and neutral".

If I understand this correctly (I'm not an electrical guy) if one installs a GFCI on given circuit, then any subsequent regular outlets further away from the panel and on the same circuit are also protected. correct?


That is correct as long as the receptacles downstream are wired to the LOAD side of the GFCI receptacle and not just daisy chained off of the LINE wiring into the receptacle.

#8 pelaw

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Posted 28 September 2013 - 05:19 PM

No.  Receptacles are connected in parallel, precisely to allow for operation of multiple receptacles.  Neutral current flowing through receptacle 1 does not flow through receptacle 2.  Flow of current through the receptacle, and ultimately the appliance, is what is being sensed by the GFCI.  There is no fault condition at the receptacles, therefore GFCI will not trip.






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