2011 210.4 and 240.15(b)

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MannyBurgos

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Waukegan, IL
Im a little confused on 210.4(b) disconnecting means for mwbc's. Can you or can you not use a single pole breaker for mwbc per 240.15(b)(1)? It says you can with identified handle ties so what does this really mean?
 
MannyBurgos said:
Im a little confused on 210.4(b) disconnecting means for mwbc's. Can you or can you not use a single pole breaker for mwbc per 240.15(b)(1)? It says you can with identified handle ties so what does this really mean?
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It means you can use 2 single pole breakers but they have to be tied together with a handle tie. So you would still be turning off both circuits
 
MannyBurgos said:
Im a little confused on 210.4(b) disconnecting means for mwbc's. Can you or can you not use a single pole breaker for mwbc per 240.15(b)(1)? It says you can with identified handle ties so what does this really mean?
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Yes you can use single pole breakers for MWBC. Under the requirement the breakers have to be side-by-side. The handle tie makes it so you can't just turn one of the breakers off. You have to turn all two or three breakers off to de-energize any one branch.
 
qcroanoke said:
It means you can use 2 single pole breakers but they have to be tied together with a handle tie. So you would still be turning off both circuits
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Thank you. Now i fully understand. That's what i thought. It seems odd to me as inspectors have not calles me out on this. Now that im thinking about it, one of my local jurisdiction has amended "no 2 pole single tie breakers on circuits less than 30 amps." How do i get around 240.15(b) on this one?
 
MannyBurgos said:
Thank you. Now i fully understand. That's what i thought. It seems odd to me as inspectors have not calles me out on this. Now that im thinking about it, one of my local jurisdiction has amended "no 2 pole single tie breakers on circuits less than 30 amps." How do i get around 240.15(b) on this one?
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I'm not sure I understand the quoted local amendment language. Can you clarify?
 
texie said:
I'm not sure I understand the quoted local amendment language. Can you clarify?
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That's how it is written on the amendment. I am confused on that one as well. I will contact inspector tomorrow and ask for a clarification and see how it conforms or not with 240.15(b). I take it as no single tie branch circuits where the amp rating is less than 30 amps. It might mean no mwbc on 20 amp or lower breakers... he probably does not want mwbc's for general lighting.
 
MannyBurgos said:
That's how it is written on the amendment. I am confused on that one as well. I will contact inspector tomorrow and ask for a clarification and see how it conforms or not with 240.15(b). I take it as no single tie branch circuits where the amp rating is less than 30 amps. It might mean no mwbc on 20 amp or lower breakers... he probably does not want mwbc's for general lighting.
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Well, if they have any local amendments that are somehow codified by local ordinance, etc. then that is their choice if sense can be made of it. Where I draw the line are AHJs that have adopted the NEC but then try to require things that are not NEC required or even forbidden by the NEC just because "we like to see such and such" or some other local urban legend code that is not in writing. Over the years I've seen too many local AHJs requiring things that are in conflict with the NEC that they have adopted by law and have nothing in writing to back up their local "rules". This should not be tolerated.
 
MannyBurgos said:
Thank you. Now i fully understand. That's what i thought. It seems odd to me as inspectors have not calles me out on this. Now that im thinking about it, one of my local jurisdiction has amended "no 2 pole single tie breakers on circuits less than 30 amps." How do i get around 240.15(b) on this one?
Click to expand...

MannyBurgos said:
That's how it is written on the amendment. I am confused on that one as well. I will contact inspector tomorrow and ask for a clarification and see how it conforms or not with 240.15(b). I take it as no single tie branch circuits where the amp rating is less than 30 amps. It might mean no mwbc on 20 amp or lower breakers... he probably does not want mwbc's for general lighting.
Click to expand...

I think your amendment means you can't use single breakers with handle ties. But you must use a 2-pole breaker. I recall someone near me that said a local AHJ had the same amendment. Their reasoning was someone could remove the handle tie.:roll:

I suppose they think no one could ever replace a 2-pole with (2) single poles though!:)
 
Little Bill said:
I think your amendment means you can't use single breakers with handle ties. But you must use a 2-pole breaker. I recall someone near me that said a local AHJ had the same amendment. Their reasoning was someone could remove the handle tie.:roll:

I suppose they think no one could ever replace a 2-pole with (2) single poles though!:)
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Your probably right. i always though 2 poles or (2) singles poles were the same as long as there was a handle tie. Tomato tomatoe.
 
You are welcome. The free trip feature and the trip to center position combine to make it unlikely that the handle tie will allow one breaker to trip the other.
 
MannyBurgos said:
I see what you are saying. I thought they did the same thing. I thought handle ties were considered a common trip. Oops! I guess I was wrong. Thanks for clarifying.
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GoldDigger said:
You are welcome. The free trip feature and the trip to center position combine to make it unlikely that the handle tie will allow one breaker to trip the other.
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IMO, the tripping is not why they require the handle ties. It is to insure that both circuits get turned off before working on them.

P.S. don't construe my answers to me agreeing with the new rules for MWBC!:rant:
 
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