Wire Insulation

[GlennG]

Does anyone have any kind of chart or any information regarding what the abreviation letters on a wire stand for. For example i know that the HH in THHN stands for a double heat rating (90c), and the W in THWN stands for wet locations but what about all the other letters? If im not mistaken they all indicate something about the wires use. Is anyone familiar with this?

Also is THHN is only rated for dry/damp locations then why do i see it used everywhere???? Am i missing something there or is that a violation every time i see in wet locations?

 

[raider1]

The T stands for thermalplastic.

As for why you see THHN used in wet locations, most THHN is also dual rated as THWN or THWN-2 which would be rated for a wet location. This dual marking should be on the wire itself.

Chris

 

[GlennG]

what about all of the other letters in the different types of wire? I saw in a book one time they broke all the letter meanings down, so essentially if you could figure out if the proper wire was being used in a location even if u weren't familiar with what it was.

As for the THHN having a dual rating, that would explain it, i will have to look closer next time,

 

[jumper]

I am searching. I know the chart you want. I found it once because I was curious.

If no one else has it, I will find it again.

 

[jumper]

Found one chart, not exactly what you want but helpful.

http://www.generalcable.com/NR/rdonlyres/264A29F5-72AE-43FF-9C3F-3963CCDEACD0/0/Spec_A075.pdf

I will look more later.

 

[480sparky]

How 'bout T310.13(A)?

 

[jusme123]

How 'bout T310.13(A)?

ding ding ding

 

[jumper]

How 'bout T310.13(A)?

Yeah that tells you a lot, but weird ones like SIS for switchboards got me curious. S for switchboards, but what about IS?

It was an idle curiousity thing. I admit, I am a geek.:grin:

 

[GlennG]

Found one chart, not exactly what you want but helpful.

http://www.generalcable.com/NR/rdonlyres/264A29F5-72AE-43FF-9C3F-3963CCDEACD0/0/Spec_A075.pdf

I will look more later.

This is a good chart, basically what i was talking about. I need to try and get a copy of the chart i saw in an instructional book to show you all, it broke it down one step further than this and gave the meanings of all the letters, so if you had a piece of THHN, and for arguments sake didnt know what its uses were, u can figure it out by knowing the meanigns of the abbreviated letters..

Article 310.13 (A) is good, but not quite what i was looking for. Although i guess aslong as i keep that handy i wouldnt need to know anything further.. THanks- Glenn

 

[jumper]

Found it!

http://www.ul.com/global/documents/...ctrical/newsletters/W&CMG_April2007_Final.pdf

 

[GlennG]

Found it!

http://www.ul.com/global/documents/...ctrical/newsletters/W&CMG_April2007_Final.pdf

THis is awesome!! Especially page 23, that was what i was asking about originally. I also feel like that chart gives a little more than 310.13 (A) , although i didn't compare yet. Thanks for your persistence in locating this.


-Glenn