Type NM cable in Conduit

[charlie]

Section 334.15(C) now states, "NM cable used on a wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing. conduit or tubing shall utilize a nonmetallic bushing or adaptor at the point where the cable enters the raceway. Metal conduit and tubings and metal outlet boxes shall be grounded."

Since the NM cable can not be secured within 12" of the outlet box, 334.30 has a sentence that states, "Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway."

I was going to question the argument that it is now permitted to use a short run of EMT down a basement wall to a handy box but I found the rest of the change in section 334.30. For years, this has been done and has not met the technical requirements of the Code; however, with these two changes, it will be acceptable when the 2005 NEC is adopted (just don't forget the raceway fill restrictions).

 

[bphgravity]

Re: Type NM cable in Conduit

So, would this still not be permitted in another locaton like a garage?

 

[charlie]

Re: Type NM cable in Conduit

So, would this still not be permitted in another location like a garage?

Sorry, I quoted the exact language from the NEC. I would be interested what inspectors have to say about it.

 

[websparky]

Re: Type NM cable in Conduit

Hi Charlie,

When 1/2" emt is used in a basement to protect 12-2 NM dropping down a wall to a receptacle, I see no harm with the fill ratio even if it were applicable at 60%. Here is a quote from the hand book in chapter 9.

The maximum fill requirements do not apply to short sections of conduit or tubing used for the physical protection of conductors and cables. Cables are commonly protected from physical damage by conduit or tubing sleeves sized to enable the cable to be passed through with relative ease without injuring or abrading the protective jacket of the cable.

 

[charlie]

Re: Type NM cable in Conduit

Dave, what NEC section says that (the commentary in the handbook is just an opinion the same as our opinions are here)?

I also wonder about the idea of using #14 type NM and looping it in 1/2" EMT? I know its a little tight but two cables will fit nicely and can be pushed in by hand.

 

[gimpyfac]

Re: Type NM cable in Conduit

Are there any UL listed NM to conduit connectors out there, if so give example.

 

[bphgravity]

Re: Type NM cable in Conduit

Here is one from "Arlington"

EMT to NM Connector

 

[iwire]

Re: Type NM cable in Conduit

Originally posted by gimpyfac:
Are there any UL listed NM to conduit connectors out there, if so give example.

We don't need one, the new section says we can use a bushing.

 

[gimpyfac]

Re: Type NM cable in Conduit

Per 2005 code nonmetallic bushing or adapter at the point where the cable enter the raceway. What would be an adapter?

 

[charlie]

Re: Type NM cable in Conduit

Bryan just posted a picture of one.

 

[hurk27]

Re: Type NM cable in Conduit

Arlington also makes a very nice snap on plastic bushing that is UL listed for this very application. We have been using them for about 6 months now and they are great.