Connecting neutral wires of different circuits

[jap]

Yes, it is. He specifically said there were multiple neutrals from multiple circuits. An MWBC has one neutral.

There you go speculating again.... below is what he actually stated.

I've seen it a few times where someone, who didn't know what he was doing, connected all the neutrals together in a multi-gang switch box, even though the switches aren't all on the same circuit in that box. I realize this is very poor practice, and I would never do this in the field, but is there an actual NEC Code reference addressing this? The grounding conductors all go together regardless of circuit, but the neutrals need to be separated.


No where above did he state there were multiple neutrals from multiple circuits.

Only that all of the neutrals were connected together and the switches weren't all on the same circuit which could be the same description of a MWBC.

JAP>

 

[gadfly56]

There you go speculating again.... below is what he actually stated.

I've seen it a few times where someone, who didn't know what he was doing, connected all the neutrals together in a multi-gang switch box, even though the switches aren't all on the same circuit in that box. I realize this is very poor practice, and I would never do this in the field, but is there an actual NEC Code reference addressing this? The grounding conductors all go together regardless of circuit, but the neutrals need to be separated.


No where above did he state there were multiple neutrals from multiple circuits.

Only that all of the neutrals were connected together and the switches weren't all on the same circuit which could be the same description of a MWBC.

JAP>

"all the neutralS" That's the plural form of the word "neutral". That means there is MORE THAN ONE!

"aren't all on the same circuit in that box" That means there is at least two circuits. TWO IS MORE THAN ONE!

 

[jap]

"all the neutralS" That's the plural form of the word "neutral". That means there is MORE THAN ONE!

"aren't all on the same circuit in that box" That means there is at least two circuits. TWO IS MORE THAN ONE!

OK SINCE WE'RE YELLING NOW.
IF I HAVE 1 NEUTRAL FROM THE PANEL INTO THE SWITCH BOX FOR A MULTIWIRE BRANCH CIRCUIT AND 3 NEUTRALS GOING OUT OF THE SWITCH BOX TO THE LIGHTS I NOW HAVE 4 NEUTRALS TOTAL WHICH IS MORE THAN ONE!

IF I HAVE CIRCUIT 1, 3 AND 5 OF A MULTI-WIRE BRANCH CIRCUIT INTO THE SWITCH BOX THAT MEANS THERE'S AT LEAST TWO CIRCUITS, ACTUALLY THERE ARE 3.

So until the OP determines that this is not actually a MWBC there are not dangers or code violations of connecting all of the neutrals together in the box.

JAP>

 

[gadfly56]

OK SINCE WE'RE YELLING NOW.
IF I HAVE 1 NEUTRAL FROM THE PANEL INTO THE SWITCH BOX FOR A MULTIWIRE BRANCH CIRCUIT AND 3 NEUTRALS GOING OUT OF THE SWITCH BOX TO THE LIGHTS I NOW HAVE 4 NEUTRALS TOTAL WHICH IS MORE THAN ONE!

IF I HAVE CIRCUIT 1, 3 AND 5 OF A MULTI-WIRE BRANCH CIRCUIT INTO THE SWITCH BOX THAT MEANS THERE'S AT LEAST TWO CIRCUITS, ACTUALLY THERE ARE 3.

So until the OP determines that this is not actually a MWBC there are not dangers or code violations of connecting all of the neutrals together in the box.

JAP>

Fine then. We'll go with your assumption that the OP is an idiot and can't identify MWBC's. :roll::roll:

 

[jap]

I've seen it a few times where someone, who didn't know what he was doing, connected all the neutrals together in a multi-gang switch box, even though the switches aren't all on the same circuit in that box. I realize this is very poor practice, and I would never do this in the field, but is there an actual NEC Code reference addressing this? The grounding conductors all go together regardless of circuit, but the neutrals need to be separated.

Hey Jeff,

I'd never intentionally do it either, but, just to clear this up for those that haven't been in the electrical field all their life, aren't we talking about those who may not have known any better and connected neutrals from different circuits together in a switchbox with the mind set of " It doesn't make any difference, they all go back to the same place anyway?" which is dangerous and an actual code violation and causes headaches when an upgrade is required since it will immediately trip any Arc Fault or Ground Fault overcurrent device we may have to install to pass inspection?

JAP>

 

[jap]

Fine then. We'll go with your assumption that the OP is an idiot and can't identify MWBC's. :roll::roll:

There you go speculating once again.

I think the OP knows exactly what he's talking about, but, there may be some on this forum that have not been in the industry all their lives, and, do not understand that we are talking about mixing neutrals of different circuits, which was not clear in the original post.

JAP>

 

[jap]

Fine then. We'll go with your assumption that the OP is an idiot and can't identify MWBC's. :roll::roll:

I don't refer to people with that type of language, so , you'd be best to quit speculating about my assumptions.


JAP>

 

[roger]

I don't refer to people with that type of language, so , you'd be best to quit speculating about my assumptions.


JAP>

Well you should read the OP and take it as it is worded and not keep trying to make it into something that you want it to be. If you are taking a test do not read more into a question than the words.

Once again, from the OP's actual wording, "even though the switches aren't all on the same circuit in that box."

You can read it all you want but the fact is that if a "Single" circuit could have handled the load in the switch box, there would not have been the need for any additional circuits.

So you have never wired a switch that may be going to a bath fan that consist of multiple circuits? Or a multi gang entry switch that may be feeding an exterior circuit or circuits along with separate interior circuits?

The additional circuits in the box constitute more than 1 circuit therefore I use my right to consider it "multiple circuits".

:huh: That's what we're talking about not a single MWBC

Just because there are multiple circuits in the switch box, and, all of the Neutrals are tied together, that does not mean that there is a danger or a violation.

Sure there is and the article sections have been posted.

And there's no way of knowing that right now.

Not by what the OP originally stated anyway.

Sure there is and article sections have been posted.

Roger

 

[MAC702]

We are talking about two different things now.

A single- or 3-phase MWBC is a single circuit with a single neutral.

But there are plenty of times that there are more than one circuit, each with a hot and neutral, and no part of a MWBC, in the same box, especially when dealing with switches.

 

[jap]

Well you should read the OP and take it as it is worded and not keep trying to make it into something that you want it to be. If you are taking a test do not read more into a question than the words.

So you have never wired a switch that may be going to a bath fan that consist of multiple circuits? Or a multi gang entry switch that may be feeding an exterior circuit or circuits along with separate interior circuits?

:huh: That's what we're talking about not a single MWBC

Sure there is and the article sections have been posted.

Sure there is and article sections have been posted.

Roger

Noted.
And long winded.

JAP>

 

[jap]

We are talking about two different things now.

A single- or 3-phase MWBC is a single circuit with a single neutral.

But there are plenty of times that there are more than one circuit, each with a hot and neutral, and no part of a MWBC, in the same box, especially when dealing with switches.

If a MWBC is a single circuit, what circuit number do you put on the 3 different phase conductors?

JAP>

 

[jap]

Well you should read the OP and take it as it is worded and not keep trying to make it into something that you want it to be. If you are taking a test do not read more into a question than the words.Roger

By the way, You seem to be making this about what you want it to be.

How do you know by the original post that the OPs beef with this whole thing may not have been having 10 white wires under 1 big blue wire nut and maybe not have had anything to do with neutral return current at all?

You don't.

JAP>

 

[jap]

You made it about EMF and all the technical stuff immediately in post 2.

oh well,,,, I surrender.

JAP>

 

[MAC702]

If a MWBC is a single circuit, what circuit number do you put on the 3 different phase conductors?

These are two different uses of the word "circuit."

Let's look at a water heater. This is typically 240V 30A and no neutral; right? This is one circuit, right? Power goes out on #1 and returns on #3. It is labeled with both numbers.

 

[jap]

These are two different uses of the word "circuit."

Let's look at a water heater. This is typically 240V 30A and no neutral; right? This is one circuit, right? Power goes out on #1 and returns on #3. It is labeled with both numbers.

Yea, I take that one back.

JAP>

 

[roger]

and maybe not have had anything to do with neutral return current at all? .

Roger

Disregard all of my posts but it may be time to let it go and listen to the other posters in this thread. You do realize that if the circuit is not a designed "Line - Line" or "Phase - Phase" circuit there will be current returned on the neutral or grounded conductor don't you?

Roger

 

[jap]

You do realize that if the circuit is not a designed "Line - Line" or "Phase - Phase" circuit there will be current returned on the neutral or grounded conductor don't you?

Roger

I didn't know that. Thanks for explaining that to me.
JAP>

 

[jeff48356]

Hey Jeff,

I'd never intentionally do it either, but, just to clear this up for those that haven't been in the electrical field all their life, aren't we talking about those who may not have known any better and connected neutrals from different circuits together in a switchbox with the mind set of " It doesn't make any difference, they all go back to the same place anyway?" which is dangerous and an actual code violation and causes headaches when an upgrade is required since it will immediately trip any Arc Fault or Ground Fault overcurrent device we may have to install to pass inspection?

JAP>

Yes, I'm talking about multi-gang switch boxes with neutrals of different lighting circuits. No MWBC's here; all independent circuits. Also, the house was built in 1975, so no AFCI breakers. I've already fixed the problem, but I was wondering what the actual NEC code reference was in regards to this.

 

[jap]

Yes, I'm talking about multi-gang switch boxes with neutrals of different lighting circuits. No MWBC's here; all independent circuits. Also, the house was built in 1975, so no AFCI breakers. I've already fixed the problem, but I was wondering what the actual NEC code reference was in regards to this.

Yes a violation, and , as others have said, very common and creates all of the misfortunes listed starting at Post #2.

Even if not made during the original install, some are made by adding something after the fact where the installer chose to tie to the neutral that was most handy and maybe not the neutral associated with the circuit it was supposed to be.

As others have said, this usually rears it's ugly head, when the requirement of GFI or AFCI overcurrent protection is put into play, and the breakers trip due to the imbalance of the return current on the shared neutral.

P.S. I figured that was what you were talking about all along, but, it never hurts to stir it up a little bit.

JAP>

 

[electricalist]

I think this thread has scarred me.