# Multiple wire branch circuit (shared neutral)



## erics37 (May 7, 2009)

In 210.4(B) it says:

"*(B) Disconnecting Means.* Each multiwire branch circuit
shall be provided with a means that will simultaneously
disconnect all ungrounded conductors at the point where
the branch circuit originates."

There's also an informational note that refers you to 240.15(B), which says:

"*(1) Multiwire Branch Circuit.* Individual single-pole circuit
breakers, with identified handle ties, shall be permitted
as the protection for each ungrounded conductor of multiwire
branch circuits that serve _only single-phase line-to-neutral
loads._"


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## Fate (Feb 21, 2011)

It is a new change to the 2008 NEC.

*210.4 Multiwire Branch Circuits.*

*(B) Disconnecting Means.* Each multiwire branch circuit
shall be provided with a means that will simultaneously
disconnect all ungrounded conductors at the point where
the branch circuit originates.


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## BBQ (Nov 16, 2010)

RlxdN10sity said:


> A friend of mine is telling me that it is now code for two ungrounded conductors sharing a neutral must have a common trip. It is my understanding that in order to have a common trip this would mean a DP breaker. Is this the code and when did it become code? Thanks.


It does not have to be common trip.

A two pole breaker or two single pole breakers with approved handle ties meet the requirement.


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## raider1 (Jan 22, 2007)

BBQ said:


> It does not have to be common trip.
> 
> A two pole breaker or two single pole breakers with approved handle ties meet the requirement.


I agree with Bob.

There has been a lot of confusion about the requirements in 210.4(B) in regards to common trip.

2 single pole breakers with an identified handle tie satisfies 210.4(B).

Chris


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## RlxdN10sity (Apr 8, 2007)

So really the main thing is the handles need to be tied together for purposes of disconnecting both circuits so no one gets jacked by the neutral when working on circuits. My situation is a HO Square D panel full of tandems with MWBC's. Since the ungrounded conductors must be on alternate phase, only every other circuit has handles next to each other. I cannot seem to find that Square D makes the handle ties I need. I was told you could just tie them together with a piece of wire. Seems kinda cheesy to me, but if it meets the requirement and I have no other practical choice then that is what I'll have to do.


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## backstay (Feb 3, 2011)

RlxdN10sity said:


> So really the main thing is the handles need to be tied together for purposes of disconnecting both circuits so no one gets jacked by the neutral when working on circuits. My situation is a HO Square D panel full of tandems with MWBC's. Since the ungrounded conductors must be on alternate phase, only every other circuit has handles next to each other. I cannot seem to find that Square D makes the handle ties I need.* I was told you could just tie them together with a piece of wire.* Seems kinda cheesy to me, but if it meets the requirement and I have no other practical choice then that is what I'll have to do.


 
A piece of wire is NOT a approved handle! Would this type help? I realize it's a 20/50 but you get the idea.


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## Shockdoc (Mar 4, 2010)

I prefer 8 penny nails cut to size for SQd handle ties. Until they canmake their own it is up to you to improvise. That code is a load of horsesh*t anyway becuase some moron on the code panel disconnected a mwbc neutral and fried a few thousend dollars worth of stuff.


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## Fibes (Feb 18, 2010)

Shockdoc said:


> I prefer 8 penny nails cut to size for SQd handle ties.


 Unless an inspector is blind or just plain sorry that won't work.


Shockdoc said:


> Until they canmake their own it is up to you to improvise.


 SQ D has made handle ties for their breakers for years


Shockdoc said:


> That code is a load of horsesh*t anyway becuase some moron on the code panel disconnected a mwbc neutral and fried a few thousend dollars worth of stuff.


I agree but I don't think the ROP for this came from a CMP member.


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## RlxdN10sity (Apr 8, 2007)

backstay said:


> A piece of wire is NOT a approved handle! Would this type help? I realize it's a 20/50 but you get the idea.


I actually have 2 quad/tandems in this panel. They are 2-30/15 HOMT. Of course the center breaker is common trip and handles are tied. But what can I do about the outer two handles? Is there a hoop bracket I can tie them with? If so I could change out to all quads and hoops and be good to go. I wonder if I could tie the outer handle to the adjacent quad below it. I think Square D has a handle tie that might do that. Thanks again everyone offering your insight / solutions.


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## macmikeman (Jan 23, 2007)

Pull the quad out and use that space for a main for the new panel you are now going to install in order to ensure that you have enough spaces to put in nice new safe compliant wiring and handle tie breakers ( or a double pole) for the multiwire branch circuit that is not supplying any areas that would require an arc fault breaker........ And make some money doing it.


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## AFOREMA1 (Nov 23, 2009)

BBQ said:


> It does not have to be common trip.
> 
> A two pole breaker or two single pole breakers with approved handle ties meet the requirement.


BBQ the second half of your post is correct it can be a double pole breaker or two singles tied together. But your first statement is wrong it does have to be a common trip by one of the above means.


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## RlxdN10sity (Apr 8, 2007)

Looks like the HOMHT will do the trick. I just have to organize the circuits accordingly. Upper handle to the next space up and lower handle to the next space down. Since common trip is not necessary, looks like I'll be in good shape with this handle tie.


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## RlxdN10sity (Apr 8, 2007)

AFOREMA1 said:


> BBQ the second half of your post is correct it can be a double pole breaker or two singles tied together. But your first statement is wrong it does have to be a common trip by one of the above means.



It is my understanding that 2 singles tied together is not common trip. The trip mechanism is internal to the breaker. The only way to truly have 2 circuits with a common trip is to use a DP breaker. Otherwise you still have independent trip between two single pole breakers that have been tied together allowing for ready identification of each of the ungrounded conductors sharing a neutral. Maybe this is only the case with Square D, I'm not sure.


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## AFOREMA1 (Nov 23, 2009)

RlxdN10sity said:


> It is my understanding that 2 singles tied together is not common trip. The trip mechanism is internal to the breaker. The only way to truly have 2 circuits with a common trip is to use a DP breaker. Otherwise you still have independent trip between two single pole breakers that have been tied together allowing for ready identification of each of the ungrounded conductors sharing a neutral. Maybe this is only the case with Square D, I'm not sure.


They must trip mechanically at the same time as each other if using multiple single breakers . The internal timing of the trip, which at most will be milliseconds in difference, is not addressed in the code only the mechanical connection so that they must be tripped simultaneously. Or by means of a common physical tripping device such as a tie between breakers.


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## Magnettica (Jan 23, 2007)

Screw the handle tie!


Wire & install the right OCPD!


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## don_resqcapt19 (Jul 18, 2010)

While Square D does make a two pole handle tie, it is junk and a tight fitting screw or nail is a much better handle tie than what they sell you (just not compliant with the code rule, but physically a better installation) and if you have bolt on breakers, you have to unbolt one to install the handle tie. Their three pole handle tie is of a much better design. It has a clip that goes over the three handles and a pin that you drop down through the clip and the holes in the breaker handles.


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## don_resqcapt19 (Jul 18, 2010)

AFOREMA1 said:


> ... Or by means of a common physical tripping device such as a tie between breakers.


A handle tie provides a means of common disconnect, but does not provide a means of common trip. The second breaker may or may not be turned off when one a pair of handle tie breakers trips. When using handle ties with breakers that to not have a trip indicator, other than handle position, you will have no visible indication that the breaker has tripped. Both breakers will appear to be on or both breakers will appear to be off.


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## Dennis Alwon (May 9, 2009)

RlxdN10sity said:


> I actually have 2 quad/tandems in this panel. They are 2-30/15 HOMT. Of course the center breaker is common trip and handles are tied. But what can I do about the outer two handles? Is there a hoop bracket I can tie them with?


I suspect that breaker was designed as a dp 50 with 2 sp pole breakers. You can get a dp 50 with dp 20 already tied. I suspect you can get a handle tie for the two sp. breakers.


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## AFOREMA1 (Nov 23, 2009)

don_resqcapt19 said:


> A handle tie provides a means of common disconnect, but does not provide a means of common trip. The second breaker may or may not be turned off when one a pair of handle tie breakers trips. When using handle ties with breakers that to not have a trip indicator, other than handle position, you will have no visible indication that the breaker has tripped. Both breakers will appear to be on or both breakers will appear to be off.


Really? Throw a fault in to try to make yourself right. A possible failure does not change the fact of what I said, both breakers will be switched at the same time . 

Yes a failure may occur they can occur with a factory dp breaker as well what is your point? That is why one needs to properly test when working with them to see if a fault occurred and not to just assume that they are all off or on.


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## Dennis Alwon (May 9, 2009)

AFOREMA1 said:


> Both means dp or two sp breakers with handle tie are meant to be a means of common disconnect or trip whichever word you choose.


Common disconnect is different from common trip.


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## don_resqcapt19 (Jul 18, 2010)

AFOREMA1 said:


> Really? Throw a fault in to try to make yourself right. A possible failure does not change the fact of what I said, both breakers will be switched at the same time . ...


A handle tie does not creat a common trip. The second breaker may or may not be turned off when the first breaker trips, but if it does it will be off, not tripped. Breakers are required but the UL standard and by the NEC (240.80) to be 'trip free". This term means that the breaker will trip and open the circuit when the handle is physically held in the on position. It also means that there will not be a lot of force applied to the handle when the breaker trips. Often there is not enough force to cause a second breaker, connected by a handle tie, to open. There will almost never be enough force when 3 breakers are connected by a handle tie.


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## Salvatoreg02 (Feb 26, 2011)

But there was or there still is an exception to this rule, please quote me if I'm wrong. 
Only if the MWBC feeds a device on the same yoke. Then a multiple pole CB must be used or handle ties...

Sent from my iPhone using ET Forum


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## don_resqcapt19 (Jul 18, 2010)

Salvatoreg02 said:


> But there was or there still is an exception to this rule, please quote me if I'm wrong.
> Only if the MWBC feeds a device on the same yoke. Then a multiple pole CB must be used or handle ties...
> 
> Sent from my iPhone using ET Forum


Starting with the 2008 code the handle tie rule applies to all multiwire branch circuits.


> 210.4(B) Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates.


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## Barjack (Mar 28, 2010)

I was passed by a rather thorough inspector using ceiling grid tie wire to tie 2 and 3 wire MWBC's together on a Siemens bolt on panel. It took some discussion, and some delving into the code, but he passed me. "Identified" does not mean "listed" nor does it mean "approved".



> Identified (as applied to equipment). Recognizable as
> suitable for the specific purpose, function, use, environment,
> application, and so forth, where described in a particular
> Code requirement.


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## RlxdN10sity (Apr 8, 2007)

don_resqcapt19 said:


> A handle tie does not creat a common trip. The second breaker may or may not be turned off when the first breaker trips, but if it does it will be off, not tripped. Breakers are required but the UL standard and by the NEC (240.80) to be 'trip free". This term means that the breaker will trip and open the circuit when the handle is physically held in the on position. It also means that there will not be a lot of force applied to the handle when the breaker trips. Often there is not enough force to cause a second breaker, connected by a handle tie, to open. There will almost never be enough force when 3 breakers are connected by a handle tie.



This is my understanding of what has been explained to me as well. When a breaker trips, the handle is more or less just released to center. It does not kick and drag whatever it is tied to along with it.

So just to bottom line this. A handle tie connecting both of the single pole breakers feeding the ungrounded conductors in a 2 leg MWBC satisfies the "means that will simultaneously disconnect all ungrounded conductors" portion of 210.4(B)

Correct?

Thanks again to everyone.


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## RlxdN10sity (Apr 8, 2007)

Dennis Alwon said:


> I suspect that breaker was designed as a dp 50 with 2 sp pole breakers. You can get a dp 50 with dp 20 already tied. I suspect you can get a handle tie for the two sp. breakers.



Really? Man that would be very helpful. I suspect that even though the two 20s would be tied that they would probably still be independent trip. Should be fine though. How would I refer to it? The local Square D distributor seems to think there is no such thing but I could swear I've seen it on an Apt. job we did last year. It was just like a stamped metal hoop that connected to the outside of each of the outer most breaker handles, with a rolled up tab at the trailing edge to push your thumb against to actuate the breakers. Do you have a part # or ideas on how I can get it? Thanks.


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## BBQ (Nov 16, 2010)

AFOREMA1 said:


> BBQ the second half of your post is correct it can be a double pole breaker or two singles tied together. But your first statement is wrong it does have to be a common trip by one of the above means.


No, both parts of my statement are correct.

For a multiwire branch circuit the NEC does not require common trip, it requires common means of disconnect so handle ties are all that are required for multiwire branch circuit.


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## RlxdN10sity (Apr 8, 2007)

So I found 210.7 in the 2011 NEC dealing with Multiple Branch Circuits. It says: 

"Where two or more branch circuits supply devices or equipment on the same yoke, a means to simultaneously disconnect the ungrounded conductors supplying those devices shall be provided at the point at which the branch circuits originate." 

My questions are, what is a yoke and is this the section of the code dealing with what we have been discussing here?


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## HARRY304E (Sep 15, 2010)

RlxdN10sity said:


> So I found 210.7 in the 2011 NEC dealing with Multiple Branch Circuits. It says:
> 
> "Where two or more branch circuits supply devices or equipment on the same yoke, a means to simultaneously disconnect the ungrounded conductors supplying those devices shall be provided at the point at which the branch circuits originate."
> 
> My questions are, what is a yoke and is this the section of the code dealing with what we have been discussing here?


Yes there is look in the NEC...


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## crosport (Apr 4, 2010)

Those cutler hammer breakers that come in quads are not common trip and the tie handles trip each other just fine.


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## HARRY304E (Sep 15, 2010)

crosport said:


> Those cutler hammer breakers that come in quads are not common trip and the tie handles trip each other just fine.


They doo .

But i like 2 pole Breakers..:thumbup:


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