GFCI Line & Load Neutrals Pigtails Tied Together In The Box?

[erichall1]

I just ran across a wiring scheme for a GFCI I have not seen, nor done myself before.

The Line & Load Neutrals on a GFCI have their pigtails tied together with the Neutral from the breaker panel inside the box for the GFCI.

Intuitively, this is yelling out "Wrong!" to me. Yet the GFCI appears to be working OK & trips when the Test button is depressed. Yet, I do not trust this wiring scheme at all. Essentially this seems to me to equal the same thing as if one wired both the Line & the Load Neutrals each to both the Line & Load terminals.

This wiring scheme does not seem to me to be an acceptable practice (Tying the pigtails from the Line & Load Neutrals on a GFCI together with the Neutral from the breaker panel) even if the GFCI appears to still function.

Am I correct that this is an unacceptable wiring practice for a GFCI?

I have never seen any wiring diagram anywhere for a GFCI that depicts this particular wiring scheme.

 

[GoldDigger]

I just ran across a wiring scheme for a GFCI I have not seen, nor done myself before.

The Line & Load Neutrals on a GFCI have their pigtails tied together with the Neutral from the breaker panel inside the box for the GFCI.

Intuitively, this is yelling out "Wrong!" to me. Yet the GFCI appears to be working OK & trips when the Test button is depressed. Yet, I do not trust this wiring scheme at all. Essentially this seems to me to equal the same thing as if one wired both the Line & the Load Neutrals each to both the Line & Load terminals.

This wiring scheme does not seem to me to be an acceptable practice (Tying the pigtails from the Line & Load Neutrals on a GFCI together with the Neutral from the breaker panel) even if the GFCI appears to still function.

Am I correct that this is an unacceptable wiring practice for a GFCI?

I have never seen any wiring diagram anywhere for a GFCI that depicts this particular wiring scheme.

You are talking about a GFCI receptacle, right? Since it is in a box rather than a panel?

There are two functions that the GFCI receptacle can perform using the same detector circuit:
1. It can protect against ground faults in loads connected to the receptacle by opening the circuit when the phase and neutral currents do not match within the 6 ma threshold.
2. It can protect additional receptacle outlets or devices downstream, when they are supplied through the feed-through load terminals of the GFCI.

If you are not using the feed through, then what you do with the LOAD terminals does not affect anything, and the GFCI will only detect current mismatch in loads connected to the receptacle. As long as you do not connect the LINE to the LOAD terminals or connect the supply to the LOAD rather than the LINE side. That would effectively bypass the GFCI completely, even for locally connected loads.

In the situation that you describe, the LOAD side neutral will be directly connected to the receptacle neutral, so connecting that to the supply neutral will allow neutral current from both the downstream receptacle(s) and the local receptacle to bypass the differential current transformer.
As a result the GFCI should trip whenever anything is connected to it and turned on. If it does not, then it is defective as well as miswired.

 

[GoldDigger]

In the situation that you describe, the LOAD side neutral will be directly connected to the receptacle neutral, so connecting that to the supply neutral will allow neutral current from both the downstream receptacle(s) and the local receptacle to bypass the differential current transformer.
As a result the GFCI should trip whenever anything is connected to it and turned on. If it does not, then it is defective as well as miswired.

Note: I forgot to mention that the GFCI will still trip normally when the test button is pushed, since the current imbalance the test uses is created by wiring entirely inside the GFCI and involves re-directing a small amount of current from the hot side connection, bypassing the current transformer. The incorrect neutral wiring does not interfere with that. (Although it make the test function a little less sensitive (requiring the detector to be better than spec in order to pass). I would have to draw some pictures and think about that one to be sure.)

 

[iwire]

Am I correct that this is an unacceptable wiring practice for a GFCI?

In my opinion you are correct unless the directions say to wire it with line and load neutral together.

The code violation would be 110.3(B).