Pigtailed Neutrals in Panel for Different Circuits?

[CuriousHomeInspector]

Here is a photo for consideration:

This was found as a "repair." An inspector reported finding multiple neutral conductors terminating under the same terminal screw on a bus bar in an electrical panel.

To me it doesn't feel right. If they're all in the same phase then of course the pigtail can experience 45 amps of current (30 if one of the circuits is out of phase), but here is my question:

Assuming that the "pigtail" is properly sized for the current it can experience, assuming that the wire isn't salvaged from the inside of another cable (wire is marked, so likely is not), and assuming that all non-grounded conductors involved in this configuration have common trip bars at the breaker what would the NEC violation (if any) be? (2014 or 2017)?

Thanks for allowing me to use your collective brain power.

 

[infinity]

Start with 200.4(A). It is permitted by 225.7(B) but that doesn't apply to this installation.

200.4(A) Installation. Neutral conductors shall not be used for
more than one branch circuit, for more than one multiwire
branch circuit, or for more than one set of ungrounded
feeder conductors unless specifically permitted elsewhere
in this Code.

 

[CuriousHomeInspector]

Thank you! I had just found the 200.4(A) but was not aware of the exception (that does not apply here).

I'm glad I asked and learned.

 

[infinity]

If you have two or three circuits on the same phase you do not have a MWBC. If you had two circuits on different phases you could pigtail the two neutrals and make a MWBC but you would then need either a two pole CB or a handle tie on the two single pole CB's.

 

[CuriousHomeInspector]

I've heard some argue that the wires would have to be grouped together and having 2 pieces of NM-B would negate this, but my understanding of 210.4(D) requires the grouping of the ungrounded and grounded conductors of each MWBC in at least one location in the panelboard or other equipment of origin. It seems like grouping these together with some cable ties would meet this requirement, no?

I've already ran into an electrician today that got mad at me using "phase" in this discussion. I of course was talking about the phase angle of Line 1 vs. Line 2, not the source phase at the transformer. Was told I was wrong on "split-phase" which I always thought was just a common use term that everybody agreed was a shortened form of 3-wire single phase service.

I'm also hearing the argument of "all neutrals must be individual and not joined" which I have seen on code reference for. In fact there are exemptions that specifically allow neutrals to be connected it seems.

 

[Little Bill]

All those neutrals under the wirenut are no different than landing each on the neutral bar except the pigtail that goes to the bar. That is the only wire that could see excess current.

 

[infinity]

I've heard some argue that the wires would have to be grouped together and having 2 pieces of NM-B would negate this, but my understanding of 210.4(D) requires the grouping of the ungrounded and grounded conductors of each MWBC in at least one location in the panelboard or other equipment of origin. It seems like grouping these together with some cable ties would meet this requirement, no?

I've already ran into an electrician today that got mad at me using "phase" in this discussion. I of course was talking about the phase angle of Line 1 vs. Line 2, not the source phase at the transformer. Was told I was wrong on "split-phase" which I always thought was just a common use term that everybody agreed was a shortened form of 3-wire single phase service.

I'm also hearing the argument of "all neutrals must be individual and not joined" which I have seen on code reference for. In fact there are exemptions that specifically allow neutrals to be connected it seems.

Right or wrong phase is a common term that everyone knows what it means, I usually put it in quotes. Split-phase is not mentioned in the NEC so use it at your own peril.

You can pigtail two neutrals from two 2-wire circuits and create a MWBC within the panel. Grouping is required after the splice for the short section of MWBC that has been created by the pigtail.

 

[CuriousHomeInspector]

All those neutrals under the wirenut are no different than landing each on the neutral bar except the pigtail that goes to the bar. That is the only wire that could see excess current.

I agree, but wouldn't it still be in violation of 204(A)?

Assuming those are all for 15 amp circuits, and one has an ungrounded conductor fed by a different line than the others I would think that the pigtail would experience a maximum of 30 amps, right?

 

[infinity]

I agree, but wouldn't it still be in violation of 204(A)?

Assuming those are all for 15 amp circuits, and one has an ungrounded conductor fed by a different line than the others I would think that the pigtail would experience a maximum of 30 amps, right?

Are they on opposite "phases"? If so you can create the MWBC in the panel with the pigtail. If they're one the same "phase" you cannot use the pigtail.

 

[CuriousHomeInspector]

Are they on opposite "phases"? If so you can create the MWBC in the panel with the pigtail. If they're one the same "phase" you cannot use the pigtail.

I was told this was a single phase, 3-wire residential supply and there are 3 grounded conductors coming in and one pigtail going to the bus bar (so 4 conductors total). I don't see how there isn't at least 2 conductors in the pigtail that are of the same "phase" (line?) making this unable to be a proper MWBC from my limited understanding.

That is what I like about this forum. In other areas people just claim "Oh, you can't combine neutrals" and move on... Too many people read a section of code and don't think about the exceptions etc where the group on this forum tends to think of it as a whole body of code like it should be.

P.S. While talking about grounded conductors I many times see multiple circuits landed under the same terminal in the bus bar which of course is not proper. With that in mind, is there a better term to use than "landed" at the bus bar in that instance?

 

[packersparky]

It may be compliant if the ungrounded conductors of those circuits are pigtailed also.

 

[CuriousHomeInspector]

It may be compliant if the ungrounded conductors of those circuits are pigtailed also.

Good point. I left that info out. In this case they were fed by separate breakers, not pigtailed from a common source

 

[infinity]

I was told this was a single phase, 3-wire residential supply and there are 3 grounded conductors coming in and one pigtail going to the bus bar (so 4 conductors total). I don't see how there isn't at least 2 conductors in the pigtail that are of the same "phase" (line?) making this unable to be a proper MWBC from my limited understanding.

That is what I like about this forum. In other areas people just claim "Oh, you can't combine neutrals" and move on... Too many people read a section of code and don't think about the exceptions etc where the group on this forum tends to think of it as a whole body of code like it should be.

P.S. While talking about grounded conductors I many times see multiple circuits landed under the same terminal in the bus bar which of course is not proper. With that in mind, is there a better term to use than "landed" at the bus bar in that instance?

There is no combination of three circuits from a 1Ø, 120/240 volt system where you can create a MWBC so you're correct.

I would use the word "terminate(d)" to refer to conductors that are connected to the terminal bus.

 

[kwired]

I agree with three circuits and a single phase panel - the pigtail can potentially be loaded to 30 or even 45 amps, which leaves the question of can one use a 10 or even 8 AWG pigtail if there were no extra spaces in the grounded bus?

 

[packersparky]

I agree with three circuits and a single phase panel - the pigtail can potentially be loaded to 30 or even 45 amps, which leaves the question of can one use a 10 or even 8 AWG pigtail if there were no extra spaces in the grounded bus?

No, per 200.4(A).

(A) Installation. Neutral conductors shall not be used for
more than one branch circuit, for more than one multiwire
branch circuit, or for more than one set of ungrounded feeder
conductors unless specifically permitted elsewhere in this Code.

 

[infinity]

I agree with three circuits and a single phase panel - the pigtail can potentially be loaded to 30 or even 45 amps, which leaves the question of can one use a 10 or even 8 AWG pigtail if there were no extra spaces in the grounded bus?

No but there is an exception. Post #2.

 

[JFletcher]

The installation is not compliant. as already noted, the pigtail from those 3 circuits could see as much as 60 amps if it's all 12 gauge and coming from the same leg.


rather than worrying about multiwire Branch circuits or handle ties for common trips blah blah blah, it would be much simpler to go get two more wire nuts, pigtail the neutrals 1 to 1 then land (terminate) the three pigtails on the neutral bar. If there isn't room due to ground landed on that bar, add another Ground Bar and separate some of the ground wires that are on the neutral bar.

 

[Besoeker]

Pigtails?
Just a brief explanation if someone can spare the time?

 

[JFletcher]

Pigtails?
Just a brief explanation if someone can spare the time?

a short section of wire used as a jumper or extension. Also, the coiled up wire that comes off of a GFCI or afci breaker

 

[wwhitney]

For the grounded conductor where does the feeder end and the branch circuit originate? As the pigtail is within the panel, it seems reasonable to me to say that the neutral bar and the #8 (?) pigtail are part of the feeder serving the panelboard, while the #12 (?) conductors under the wirenut are branch circuit conductors.

If you disagree, can you point to any NEC language that clarifies this?

Cheers, Wayne