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#11641 - 07/17/02 02:48 PM Insulation types
Steve T Offline

Registered: 02/14/01
Posts: 312
Loc: Oak Park, IL, USA
I recently have dealt with a contractor who has rolls of wires that are mislabeled. The rolls are labels #14 THHN stranded. The actual labeling on the insulation says #16 type TFFN or MTW. I am not going to allow the wire to be used, but the insualtion sure looks like THHN. the insulation appears to be a bit thicker than #14 THHN but I'm not sure if this is just a variance that may occur in the manufacturing process. I easily spotted some THHN #16 this contractor accidently( I hope) used before, but this # 16 was hard to tell without reading the labeling on the insulation.

I have told the contractor to have his guys read the insulation not the roll but the accident happens anyways.

Several questions--

Has anyone seen this occurence of mislabeling?

Is there an easy way to determine all the different insulation types? some are fairly similar looking.

I am going to notify the manufacturer of this occurence and see if they have knowledge of a bad batch of labeled wire or if this could be an isolated incident.

And just in case anyone was asking themselves if the contractor might be trying to pull a fast one, I saw what appeared to be full rolls from the manufacturer, but you just never know.

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#11642 - 07/20/02 04:44 AM Re: Insulation types
spkjpr Offline

Registered: 12/01/00
Posts: 226
Loc: Sedalia,MO, USA
Steve, NFPA 79 is the standards for machinery reg. I thought at one time they could be viewed on the web but all I got was that they had to be bought. Hope this helps.

#11643 - 07/30/02 09:26 PM Re: Insulation types
Steve T Offline

Registered: 02/14/01
Posts: 312
Loc: Oak Park, IL, USA
If this is a dumb question please let me know.

#11644 - 07/31/02 04:45 AM Re: Insulation types
Gwz Offline

Registered: 04/29/02
Posts: 199



310.13 and

Table 310.13 (Application Provisions) column.

Are some sections.

[This message has been edited by Gwz (edited 07-31-2002).]


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