# breaker for a 12/3



## user4818 (Jan 15, 2009)

Under the 2008 NEC, yes, you do.


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## jwjrw (Jan 14, 2010)

Peter D said:


> Under the 2008 NEC, yes, you do.


handle tie will work too.


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## CFine (May 20, 2008)

2 conductors 1 neutral? if your feeding half the living room with one circuit and the other half with the other? how are you keeping neutrals separated since it has to be af protected?


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## drsparky (Nov 13, 2008)

I agree with Cfine.


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## BuzzKill (Oct 27, 2008)

CFine said:


> 2 conductors 1 neutral? if your feeding half the living room with one circuit and the other half with the other? how are you keeping neutrals separated since it has to be af protected?


 this could be one monumental break through in electrical engineering!


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## McClary’s Electrical (Feb 21, 2009)

CFine said:


> 2 conductors 1 neutral? if your feeding half the living room with one circuit and the other half with the other? how are you keeping neutrals separated since it has to be af protected?


 

Yes, it's called a multi wire branch circuit. I run them all the time and you don't have to kepp neutrals seperated. You just have to keep phases fed from different phases. Hence, the handle tie. An inexperienced worker can burn up stuff with a MWBC if they don't konw what they're dealing with (like a few I read here)


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## Dennis Alwon (May 9, 2009)

mcclary's electrical said:


> Yes, it's called a multi wire branch circuit. I run them all the time and you don't have to kepp neutrals seperated. You just have to keep phases fed from different phases. Hence, the handle tie. An inexperienced worker can burn up stuff with a MWBC if they don't konw what they're dealing with (like a few I read here)



If you use AFCI you cannot run a MWBC-- they don't make a dp combo afci. That is what Cfine was trying to say.


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## CFine (May 20, 2008)

mcclary's electrical said:


> Yes, it's called a multi wire branch circuit. I run them all the time and you don't have to kepp neutrals seperated. You just have to keep phases fed from different phases. Hence, the handle tie. An inexperienced worker can burn up stuff with a MWBC if they don't konw what they're dealing with (like a few I read here)


I've never ran MWBC so i Dunno much about them. I'm basing what i said off two circuit going their. How would you wire up a mwbc then? just share the neutral and keep phases separated at the duplexes?


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## Dennis Alwon (May 9, 2009)

CFine said:


> I've never ran MWBC so i Dunno much about them. I'm basing what i said off two circuit going their. How would you wire up a mwbc then? just share the neutral and keep phases separated at the duplexes?


Yes, the neutral gets shared but remember that is a problem now with the requirement of AFCI


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## CFine (May 20, 2008)

ahh ok, yea that would be. the side jobs i've done, i've just used one circuit for the living room. never saw a reason for running 2 their.


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## abond82 (Feb 9, 2009)

Actually...... You can now AFCI protect a multiwire branch circuit.

http://www.sea.siemens.com/us/Produ...AFCI/Pages/2_pole__Combination_Type_AFCI.aspx


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## codeone (Sep 15, 2008)

abond82 said:


> Actually...... You can now AFCI protect a multiwire branch circuit.
> 
> http://www.sea.siemens.com/us/Produ...AFCI/Pages/2_pole__Combination_Type_AFCI.aspx


 Thanks for the link!:thumbup:


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## abond82 (Feb 9, 2009)

pretty cool huh??!!


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## user4818 (Jan 15, 2009)

Oh, that reminds me. I just saw 2-pole Murray AFCI breakers at HD the other night. $79 a piece, which isn't too bad considering they are around $35 a pole normally. I would actually start running MWBC's to bedrooms again now that a 2-pole AFCI is readily available.


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## 480sparky (Sep 20, 2007)

Peter D said:


> Oh, that reminds me. I just saw 2-pole Murray AFCI breakers at HD the other night. $79 a piece, which isn't too bad considering they are around $35 a pole normally. I would actually start running MWBC's to bedrooms again now that a 2-pole AFCI is readily available.


 
Really?


You honestly are going to do that?





Wow.
















I didn't think anyone made 3-wire zip cord.
























:laughing:


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## McClary’s Electrical (Feb 21, 2009)

Dennis Alwon said:


> If you use AFCI you cannot run a MWBC-- they don't make a dp combo afci. That is what Cfine was trying to say.


 


If you gathered that,,,,from what he wrote,,,,you need to read palms or predict futures or something. That is not anything similar to his post


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## Dennis Alwon (May 9, 2009)

mcclary's electrical said:


> If you gathered that,,,,from what he wrote,,,,you need to read palms or predict futures or something. That is not anything similar to his post


Well I read it again and I get the same idea. AF = Afci Sorry that was my take on it . Obviously I was wrong about making 2 pole combo afci so....


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## JoeKP (Nov 16, 2009)

Why is this in the Violation section?


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## eddy current (Feb 28, 2009)

The NEC requires AFCI protection in a living room? Where else do you have to use AFCI's?
In Canada we only need to use AFCI's in bedrooms. 

Where does the NEC require GFI's?
We need them within 3 feet of a sink and outside.


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## abond82 (Feb 9, 2009)

All outlets serving a counter top in kitchen, bathrooms, outside, garages. Any additional wet areas.


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## BuzzKill (Oct 27, 2008)

eddy current said:


> Where does the NEC require GFI's?
> .


 just about f'n everywhere now...it's a racket


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## abond82 (Feb 9, 2009)

abond82 said:


> All outlets serving a counter top in kitchen, bathrooms, outside, garages. Any additional wet areas.


 
that was for the GFCI's. 

AFCI's are now required for all outlets in the 2008 NEC.


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## 480sparky (Sep 20, 2007)

abond82 said:


> that was for the GFCI's.
> 
> AFCI's are now required for all outlets in the 2008 NEC.


You need to read 210.12.


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## abond82 (Feb 9, 2009)

480sparky said:


> You need to read 210.12.


Are you telling me to read the article??? Because I have. It was a general answer, it is basically everywhere or indoor general use outlets if that makes it more clear for you.


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## 480sparky (Sep 20, 2007)

abond82 said:


> Are you telling me to read the article??? Because I have. It was a general answer, it is basically everywhere or indoor general use outlets if that makes it more clear for you.


 
It's _too_ general.


Stove recep.

Range recep.

Oven Recep.

Refridgerator recep.

Microwave recep.

Disposal recep.

Sump pump recep.

Kitchen c'top receps.

Bath receps.

Outside receps.

Garage receps.

Laundry receps.

Dryer recep.

Exterior lighting.

Detached structures (garage, shed, etc)

outlets in unfinished basements.

Crawlspace outlets

Attic outlets.


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## abond82 (Feb 9, 2009)

its not to general for anyone with common sense, i didnt really have time to list every location that u dont have to protect like you did. I thought saying "general use outlets (which wouldnot be any appliance circuit)" would get the points across. BUT THANKS FOR THE EXTREME DETAIL, I didnt think the guy from canada was that concerned. I just thought he was curious about the difference from his code.


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## abond82 (Feb 9, 2009)

and obviously we arent going to AFCI protect a GFCI protected circuit......


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## JoeKP (Nov 16, 2009)

abond82 said:


> and obviously we arent going to AFCI protect a GFCI protected circuit......


you cant be too safe :whistling2:


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## 480sparky (Sep 20, 2007)

abond82 said:


> its not to general for anyone with common sense, i didnt really have time to list every location that u dont have to protect like you did. I thought saying "general use outlets (which wouldnot be any appliance circuit)" would get the points across. ............


How much _more_ 'general' than.... 



abond82 said:


> .............AFCI's are now required for all outlets in the 2008 NEC.


....can you get? :001_huh: Can you 'broaden' this statement any more?


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## abond82 (Feb 9, 2009)

I did didnt I??????


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## nitro71 (Sep 17, 2009)

AFCI's are bull**** to make the manufactures more money. I install to code but I'll bitch about that till I die.


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## RePhase277 (Feb 5, 2008)

The problem with using a 2P breaker for an MWBC is that when one circuit trips, or you have to work on a circuit, then you have to kill another circuit (or two if 3-phase).

You are better off, from a functionality standpoint, running two 2-wire circuits.


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## Rudeboy (Oct 6, 2009)

InPhase277 said:


> The problem with using a 2P breaker for an MWBC is that when one circuit trips, or you have to work on a circuit, then you have to kill another circuit (or two if 3-phase).
> 
> You are better off, from a functionality standpoint, running two 2-wire circuits.


I agree. Avoiding MWBC as much as possible is probably a good idea. Of course I run them often, but if the panel is close enough I'll run the dedicated neutrals.


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## nitro71 (Sep 17, 2009)

If it saves you money then run them.. Buy some wire markers and mark your conductors. If the customer is picking up the cost them by all means run dedicated neutrals.


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## Rudeboy (Oct 6, 2009)

I guess it depends on what were talking about. In commercial a lot of the time I'm just going to run roundhouses if that's convenient. As soon as we adopt 2008 I imagine my mwbc's will be limited in houses. Dish/Disposal i always run a 12/3, but if the panel is close, for the kitchen receps i run two 12/2's. And then 12-2's for all the other 20a circuits... reefer, micro etc..


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## zen (Jun 15, 2009)

thanks for the replies...i think i ask the question the wrong way,,this site really does help me learn the electrical truths,,,a new employee told another that he had never used a 2 pole breaker on multi wire branch circute in new mexico the last 2 years. the other employee said here inspectors red tag for it because of the problems that could come from it,,i said id ask it here because ill surely get the best answers,,,sorry for asking a grey question.


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## 480sparky (Sep 20, 2007)

zen said:


> thanks for the replies...i think i ask the question the wrong way,,this site really does help me learn the electrical truths,,,a new employee told another that he had never used a 2 pole breaker on multi wire branch circute in new mexico the last 2 years. the other employee said here inspectors red tag for it because of the problems that could come from it,,i said id ask it here because ill surely get the best answers,,,sorry for asking a grey question.


Common disconnects weren't required prior to 1981, and after that it was only for dwellings until the 2005.


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## RePhase277 (Feb 5, 2008)

I'll be honest: I have and still do run multiwire circuits without handle tied breakers. There is nothing wrong with MWBCs, and I could care less if some unqualified jackleg accidentally opens the neutral 20 years hence. I know that my joints are bulletproof, and the neutral won't open itself.

Now in the areas where the inspector is looking, the tune is slightly different.:whistling2:


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## bobelectric (Feb 24, 2007)

CFine said:


> ahh ok, yea that would be. the side jobs i've done, i've just used one circuit for the living room. never saw a reason for running 2 their.


 I ran three in my living room :
1 for general receptacles 20 a
1 for the entertainment center 20 a
1 for the fireplace blower and receptacles at fireplace wall 15 a


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## r_merc (Jul 5, 2008)

never mind


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## r_merc (Jul 5, 2008)

abond82 said:


> and obviously we arent going to AFCI protect a GFCI protected circuit......


not necessarily true.... drop a circuit from the kitchen counter top into a dining area and it will end up being both.


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## r_merc (Jul 5, 2008)

There is another way to handle this and that is using 14/2/2 or 12/2/2 Cable It has 2 neutrals, 2 hots and EG. A bit more expensive/exotic but it has its applications.


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