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Discussion Starter · #1 ·
I guess I should of asked first.

I needed to run about 25' of conductors through a sill into some PVC pipe to wire a GFCI receptacle, a flood light device and a switch in water tight boxes. I planned on running THWN in the conduit but I could not find any locally by the foot (500' rolls were my only choice). So someone suggested using UF cable which I did and it ran just fine.

I just noticed two things. UF uses THHN conductors? I assumed it was "W", and is rated for 60 degrees? My light wanted 75 degrees.

Thank you
 

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Discussion Starter · #3 ·
It is gray 1/2" electrical conduit, oh, and for clarity, it runs up a wall, there is nothing underground.
 

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Master Electrician
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Where did you get the 60* rating? NEC Table 310.16?

Check the package, if it's UF-B cable it probably has THHN/THWN, rated 90 degrees C. Also, UF (Undergroud Feeder) cable is going to have conductors rated for wet locations.

It's been a long time since I used UF cable, so I'm trying to pull out an old memory bank...
 

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Discussion Starter · #7 ·
Where did you get the 60* rating? NEC Table 310.16?

Check the package, if it's UF-B cable it probably has THHN/THWN, rated 90 degrees C. Also, UF (Undergroud Feeder) cable is going to have conductors rated for wet locations.

It's been a long time since I used UF cable, so I'm trying to pull out an old memory bank...
I got the info from a web site selling cable, that's why I wanted to ask. It is UF-B.I have an old code book, 1999 time to upgrade :whistling2:
 

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Discussion Starter · #8 ·
This is from the manufacturer "Southwire":

Multiple conductor UF-B cable may be used for interior branch circuit wiring in residential or agricultural buildings at conductor temperatures not to exceed 90°C (with ampacity limited to that for 60°C conductors) as specified by the National Electrical Code.

I didn't notice that before.
 

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You talking to me?
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I try to never believe, at least without verifying, that the manufacturer states regarding code compliance. Since the code is updated every 3 years, things change. If you have material older than 3 years, their statement may no longer be correct. Beyond that, I have seen manufacturers claim code compliance when it actually wasn't or it was compliant in a very limited use that was not applicable to most installations.


additionally, their statements are often confusing for the layman. Your example is one that can confuse a lot of people unfamiliar with the intent.

as you pondered before, an updated code book is the best source of information. It is the only truly dependable source of information because, well, those are the rules you have to follow. If it doesn't meet the requirements in the code, it doesn't matter what the manufacturer says about it.
 

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The conductors are rated for 90 degrees, but the code limits the ocpd to the 60 degree column, so you are fine.
 
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