Regarding code of the day

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Jpflex

Jpflex

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Electrician commercial and residential
If EMT or conduit is located outside and you’re using rain tight listed couplings and connectors then the wire inside the EMT would be considered dry and would allow THHN wire instead of THHW wire? Is there a code reference to this?
 
Jpflex said:
If EMT or conduit is located outside and you’re using rain tight listed couplings and connectors then the wire inside the EMT would be considered dry and would allow THHN wire instead of THHW wire? Is there a code reference to this?
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I think 300.38 would require conductors rated for wet location regardless of the fittings used.
 
rojay said:
I think 300.38 would require conductors rated for wet location regardless of the fittings used.
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Excellent that is what I was looking for. However my company just uses THHN for everything even when I recommend THHW
 
"Inside a conduit" is not a location; the wires are in whatever location the conduit is in.

No matter how raintight your installation is, if it's outdoors, the wires must be so rated.
 
Fred B said:
Today most wire of this type is dually rated, THHN and THWN-2, giving a full 90deg rating. unless they are very specifically ordering straight THHN.
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Does anyone even make wire that is rated THHN only any more?
 
Have a look at 300.38.
Then head over to 310.10(C).
Then head over to 310.104 and review the table for you conductors choice. Look at MOT and AP.
While in 300 look at 300.50 (B)
Enjoy your read.
 
Jpflex said:
If EMT or conduit is located outside and you’re using rain tight listed couplings and connectors then the wire inside the EMT would be considered dry and would allow THHN wire instead of THHW wire? Is there a code reference to this?
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300.9 Raceways in Wet Locations Abovegrade.
Where raceways are installed in wet locations abovegrade, the interior of these raceways shall be considered to be a wet location. Insulated conductors and cables installed in raceways in wet locations abovegrade shall comply with 310.10(C).
 
rojay said:
I think 300.38 would require conductors rated for wet location regardless of the fittings used.
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I doubt that 300.38 applies to this question, as that is in Part II, Requirements for over 1000 Volts, Nominal. However that section says the same thing as the correct reference in 300.9.
 
ggunn said:
Does anyone even make wire that is rated THHN only any more?
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ActionDave said:
You can still find some that is straight THHN.
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This came up a while back and I looked at some 12-2 MC scraps I had lying around and I'm pretty sure I found a piece that only said THHN on the tracer. I don't think I've ever seen any off a spool that was just THHN (but doesn't mean there isn't).
 
electrofelon said:
This came up a while back and I looked at some 12-2 MC scraps I had lying around and I'm pretty sure I found a piece that only said THHN on the tracer. I don't think I've ever seen any off a spool that was just THHN (but doesn't mean there isn't).
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Was it AC not MC becuase MC needs to be damp rated and shouldn't have straight thhn in it.
 
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