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Jeff Eastman
07-06-2007, 09:00 AM
........

Scott Patterson
07-06-2007, 09:05 AM
It looks like a low voltage cable. If so, no. If it is not low voltage, then yes.

Jerry Peck
07-06-2007, 03:17 PM
If "exterior rated" (that would be "sunlight resistant") and it was above 8 feet high above the standing surface, no, it is not needed as it is not considered to be subject to physical damage.

If not sunlight resistant, then it needs to be in conduit regardless where it is outside.

Gunnar Alquist
07-06-2007, 04:00 PM
Jerry (or anyone else that has the reference),

That situation came up recently with me and I have been unable to locate and cite the specific reference. The NM was located under the roof at a gable end, well out of reach. I noted and recommended a conduit. The electrician said it is fine.

In the NEC, NM is allowed exterior if in a "normally dry" location and not subject to physical damage, but I was unable to find a specific reference that did not allow NM outside if not UV resistant. I checked the Southwire website for their installation instructions, but was unable to find anything not allowing standard NM to be installed outside. Their NM-B is not UV resistant.

Can anyone give me the location of the reference? Thanks

Bob Mayer
07-06-2007, 04:54 PM
I believe this is a damp location, therefor NM is not allowed. According to the NEC a Location, Damp includes "partially protected locations under canopies, marquees, roofed open porches, and like locations, ..." My take is if it is outside and precipitation (or standing or running water) cannot hit it is a damp location, if the location can come into contact with water it is a wet location. The temperature of surfaces outside can drop below the dew point and there is circulation air to provide water to condense (or to form frost).

- BOB

James Duffin
07-06-2007, 05:03 PM
I agree with Bob.....


Section 334.10(A)(1) of the NEC states that Type NM cable shall be permitted for use in "normally dry locations." Article 100 of the NEC defines a dry location as:
Location, Dry. A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.

Gunnar Alquist
07-06-2007, 05:14 PM
Bob,

Thanks. I just knew that there was something more definitive that I was missing. That was great!