ECN Forum Forums Code Related Discussion NEC & other Code issues multiwire circuits and tied breakers

" As long as the two breakers are on opposing poles of the panel buss there is no code violation"

Mike, while I'm sure everyone agrees that is a good practice, is it actually stated in the code as a requirement? Don't get me wrong, I always put them on opp legs, but what would be the violation if say it was 2 dedicated ckts with the total load on all conductors, neutral included, within their ampacity?

210.19 (A) (2) Multioutlet Branch Circuits. Conductors of branch
circuits supplying more than one receptacle for cord-andplug-
connected portable loads shall have an ampacity of
not less than the rating of the branch circuit.

This language may be a problem if the neutral capacity is not increased

Charlie

quote" Mike, while I'm sure everyone agrees that is a good practice, is it actually stated in the code as a requirement? Don't get me wrong, I always put them on opp legs, but what would be the violation if say it was 2 dedicated ckts with the total load on all conductors, neutral included, within their ampacity?"

BigB you are correct here there would not be one in that situation. However then it would not actually be a multiwire branch circuit, but two circuits sharing a grounded conductor. NEC 100-1

[This message has been edited by macmikeman (edited 08-22-2006).]

It is very difficult to find a handle tie that ties circuit breakers in positions 1, 4 and 42 together.

I seen alot of #12 Solid as a handle tie, maybe if you bent it just so...

The picture that this conjures up in my mind gave me a good chuckle. Thanks a lot.

[This message has been edited by tdhorne (edited 09-16-2006).]

True, but I always place shared-neutral MWBC's on adjacent breakers to minimize the chance of overloading the neutral.

Well I prefer to place them side by side but I don't always.

The NEC does not require them to be side by side.

Regardless none of my neutrals will be overloaded unless someone changes the locations after I leave.

Definitions, Article 100: "Branch Circuit, Multiwire. A branch circuit that consists of two or more ungrounded conductors that have a voltage voltage between them and each ungrounded conductor of the circuit and that is connected to the neutral or grounded conductor of the system."

To meet this definition, we must use phases A and B (and maybe C too).

earlydean- You are 100% correct and I will say they will need to be side by side by side. I know there aren't any words that say they need to be so physically located but that is just too easy to figure out. If they are to be simultaneously tripped that's the only way this hard nosed inspector will accept them. (Sorry Bob)

Edited causs I can't spill



[This message has been edited by George Little (edited 09-18-2006).]