# Conduit contains more than one pair of share-neutral circuits.



## Span (Apr 12, 2010)

Residential panel upgrade, existing flex conduit contains more than one pair of share-neutral circuits enter panel enclosure "not NM", to prevent electrician from landing share-neutral both hot-wire on same phase. Is there any code

section that I can use to require electrician provide cable tie or tape to group them for identify each pair share-neutral

circuit.

span


----------



## chris kennedy (Apr 12, 2010)

If your under the 08 NEC this works.



> 210.4 Multiwire Branch Circuits.(A) General. Branch circuits recognized by this article shall be permitted as multiwire circuits. A multiwire circuit shall be permitted to be considered as multiple circuits. All conductors of a multiwire branch circuit shall originate from the same panelboard or similar distribution equipment.
> 
> FPN: A 3-phase, 4-wire, wye-connected power system used to supply power to nonlinear loads may necessitate that the power system design allow for the possibility of high harmonic currents on the neutral conductor.
> 
> ...


Also note (B), handle ties required.


----------



## 480sparky (Apr 12, 2010)

chris kennedy said:
			
		

> If your under the 08 NEC this works.Also note (B), handle ties required.


No matter what year NEC you're on, then I'd say 90.1© would cover it.


----------



## chris kennedy (Apr 12, 2010)

480sparky said:
			
		

> No matter what year NEC you're on, then I'd say 90.1© would cover it.


90.1©??? You sure thats what you meant to site Ken?


----------



## 480sparky (Apr 12, 2010)

chris kennedy said:
			
		

> 90.1©??? You sure thats what you meant to site Ken?


Yep.  If you can't recognize a MWBC in a panel, you ain't got no business sticking your nose in there.

That said, CMP2 must think otherwise with their wonderful rewrite ('dummying down') of 210.4.


----------



## chris kennedy (Apr 12, 2010)

Got cha. Electricity for dummies.


----------



## Bryan Holland (Apr 13, 2010)

I think the code making panel got nervous about all the proposals calling for the complete elimination of MWBC's in total.  It seems to me this was a way to get those sentiments calmed down, while not really changing the wiring method.

I think it is kind-of funny when a someone makes the claim that MWBC's are dangerous and shouldn;t be used when considering that every service installed is really a multiwire arrangement.


----------

