ECN Forum Forums Code Related Discussion NEC & other Code issues Mixed cables and conductors in a raceway?

John,

As you might remember, I sit on the Board of Appeals. So oI would never accept an argument from anyone without a code section to back it up.
As for myself, if someone challenged me on that little 10' rule, I would listen to his side of the argument, and most likely let him do it.

358.22 specifically allows cable to be installed within EMT.

Personally, as an electrical inspector, I would cite 300.3(B) as the code section to disallow this installation. I would argue all the conductors of the circuit were not installed in the same cable assembly; either all THHN [single conductors] are in the same raceway, or all conductors are in the same cable assembly. That is the code section I woulde cite in the correction notice I would write.

You can argue all you want, I wouldn't permit this installation and my boss would back me up.

Dana:
Yes, 358.22 allows cable installed in EMT.

A violation citing 300.3(b) would be taken before the Board of Appeals here, and based on the verbage within said Article, the cited violation will not stand, and the BOA would rule against the AHJ (inspector and/or sub-code official) , and in favor of the EC or homeowner. I'm sure Harold will second this comment.

That all said, as I mentioned in a previous post, this is not a install that I see. (EMT or any type of raceway system with NMC). I also have not yet came upon anyone doing what Greg described within the OP.

I have see it before couple time in Wisconsin and really it was a hard item to back up due the NEC did not excatally describe as you say in first place and I did review the NEC { 2005 and 2008 NEC verison } and I just can not excatally nail it however jump over to Electrique Codé France { Basically a French verison of NEC but used in France } and came up a sweet spot where I found and it say with T&E { twin and earth the same as your NM cable } with extra conductor in raceway is not allowed the only time it will allowed if all indivual conductors.

Merci.
Marc

342.22, 344.22, 348.22, 350.22, 352.22, 356.22, 358.22, 360.22, and 362.22 permit cables to be installed in raceways where the cable articles permit it.
For EMT:
358.22 Number of Conductors. The number of conductors
shall not exceed that permitted by the percentage fill
specified in Table 1, Chapter 9.

Cables shall be permitted to be installed where such use
is not prohibited by the respective cable articles.

The number of cables shall not exceed the allowable percentage fill specified in Table 1, Chapter 9.

For NMB cable: 334.15(B) states:
(B) Protection from Physical Damage. Cable shall be
protected from physical damage where necessary by rigid
metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked
with the suffix -XW, or other approved means. Where passing
through a floor, the cable shall be enclosed in rigid
metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked
with the suffix -XW, or other approved means extending at
least 150 mm (6 in.) above the floor.

Conclusion: NMB cables can be installed in raceways.

Would the cable assembly (RX/BX)inside of a piece of EMT be considered bundling?

You would certainly have to apply derating appropriate to the total number of conductors.

Why would anyone want to put a metal cable inside EMT? I guess it takes all kinds.

"Physical protection"?

Wanted to throw my 2 cents in there. It's OK to sleeve the Romex, but when you reach the panel or box you must use a romex connector. So much for the Romex in the pipe all the way.
The idea of running a third circuit as THHN does not meet the code either.
SJT