Product label differs from cable identication. THHN/THWN

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TOOL_5150

Senior Member
Location
bay area, ca
Most THHN is dual rated THWN.

On a side note: on that page it states at the bottom: WARNING: DO NOT RE-IDENTIFY CONDUCTOR COLORS


Wny? I thought we can re-identify colors in a cable assembly?

~Matt
 

Telc

Member
What about when the job is inspected and they see THHN on the plastic strip inside, and flag it, when it's really THHN/THWN.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
...
On a side note: on that page it states at the bottom: WARNING: DO NOT RE-IDENTIFY CONDUCTOR COLORS


Wny? I thought we can re-identify colors in a cable assembly?

~Matt
Maybe so they can sell more of the "special 120 volt colors" to comply with the rule in 210.5(C), but if that is the case they should also have the 480 volt colors.
 

hurk27

Senior Member
I noticed on my rolls of MC cable, the Tag on the cable bundle says. THHN/THWN solid conductors.

But the clear plastic ID strip that runs the length of the cable just says THHN.

The conductors look to be THWN, why wouldn't they label the inside THHN/THWN?

This is the brand: http://www.afcweb.com/pdfs/afc_cable_catalog/afc_mclite_120_0704.pdf

Here is what my 2002 say's:

330.10 Uses Permitted.
(A) General Uses.
(12) In wet locations where any of the following conditions are met:
a. The metallic covering is impervious to moisture.
b. A lead sheath or moisture-impervious jacket is provided under the metal covering.
c. The insulated conductors under the metallic covering are listed for use in wet locations.

I'm not sure why but it looks ok by the NEC (see "c" above) unless this changed in the 2008? just keep the tag handy, and also if you have an extra, leave it for the inspector.
 
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ned L

Member
you can not tell by looking whether you have THHN or THHN/THWM. The difference is the type of PVC compound used as insulation (THWN is manufactureed with a wet rated PVC insulation). Both THHN and THHN/THWN are PVC insulation with a clear nylon skin construction, and they both have the same wall thickness requirements. I would treat this material as THHN regardless of what the tag on the bundle says, and not install it in a wet location. The only identification on the product is THHN.
 
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