# THHN / THWN Colors with White Under Colors



## 480sparky (Sep 20, 2007)

It's cheaper to make that way?


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## Dennis Alwon (May 9, 2009)

Are you saying there is the insulation thhn/thwn and there is another insulation layer between that and the conductor? I have never seen that


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## Lone Crapshooter (Nov 8, 2008)

Yes. A thin of white insulation between the color insulation and the conductor.


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## ponyboy (Nov 18, 2012)

I was getting some 3/0 cu that had that. It was a pain because it would get stuck in between the individual strands. I think we're getting the good stuff again


Sent from my iPad using Tapatalk


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## papaotis (Jun 8, 2013)

havent seen that for a long time. thought it was normal back then.


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## MTW (Aug 28, 2013)

I rarely see CME wire, but have noticed that about it in the past. I used to think they did it so you could tell if the outer jacket was damaged, but was quickly corrected and told the only reason they do it is to save money on the manufacturing process. Anyway, I think the stuff is junk.


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## 360max (Jun 10, 2011)

sounds like MTW type, Thermoplastic-insulated machine tool wire. 90°C Dry 600V. Look on cable to see if it is


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## papaotis (Jun 8, 2013)

good point 360, i think it was an industrial building that i last saw it!


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## 360max (Jun 10, 2011)

MTW wire stands for "Machine Tool Wire" and we have the THHN and THWN rating on all of our THHN electrical wire. If our wire was simply THHN rated then it would not be water resistant, however all of our single conductor THHN electrical *wire is Tri-rated for THHN, THWN and MTW.* It's a stranded or solid bare copper wire with a PVC insulation over it.

Tri rating is harder to strip


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## butcher733 (Aug 4, 2012)

360max said:


> MTW wire stands for "Machine Tool Wire" and we have the THHN and THWN rating on all of our THHN electrical wire. If our wire was simply THHN rated then it would not be water resistant, however all of our single conductor THHN electrical *wire is Tri-rated for THHN, THWN and MTW.* It's a stranded or solid bare copper wire with a PVC insulation over it.
> 
> Tri rating is harder to strip


Run that tri-rated in a control panel vs. actual mtw and you'll laugh at the difference, we got some and sent it back for actual mtw.


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## papaotis (Jun 8, 2013)

the insulations have changed over the years. didnt mtw use to be in a different group?


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## papaotis (Jun 8, 2013)

just checked, they are in different temp categories thus my confusion!


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## 480sparky (Sep 20, 2007)




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## Lone Crapshooter (Nov 8, 2008)

That is exactly what I was talking about.

Thanks 480.

LC


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## Rollie73 (Sep 19, 2010)

I get that crap up here every now and again as well. It sucks to strip


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## glen1971 (Oct 10, 2012)

Rollie73 said:


> I get that crap up here every now and again as well. It sucks to strip


Ditto.. If I remember right I've also seen other colors too - Blue with black underneath, and black with red underneath... Not sure if it is similar...


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