Skinned conductor valid reason for rejection during inspection?

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pv_n00b

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I was inspecting an electrical installation and one of the 350MCM conductors on a long pull had the outer covering skinned off for about 2 ½ ft in the panel where it was terminated. This is the part of the covering with the conductor information printed on it, the next layer down looked fine. I expect that the covering might have a few pull marks on it but not look like a snake shedding its skin. Is this a valid reason to reject that part of the installation? The contractor agreed to splice in a new section of conductor and that the way it was damaged represented poor workmanship on their part.
 
No and this has come up before.

People have posted info on this forum from wire manufacturers stating that is not an issue.
 
IMHO, I'd rather see the damaged clear coat wire terminated than to add a splice on a larger feeder wire, thereby creating a fail point.
 
pv_n00b said:
I was inspecting an electrical installation and one of the 350MCM conductors on a long pull had the outer covering skinned off for about 2 ½ ft in the panel where it was terminated. This is the part of the covering with the conductor information printed on it, the next layer down looked fine. I expect that the covering might have a few pull marks on it but not look like a snake shedding its skin. Is this a valid reason to reject that part of the installation? The contractor agreed to splice in a new section of conductor and that the way it was damaged represented poor workmanship on their part.
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"Neat and workmanlike" is not enforceable. the rest of 110.12 or other articles may come into play for damaged insulation, which may be the result of other code violations, like conduit w/ sharp edges, lack of bushings, too many bends, pull boxes sized wrong, and so on.

If the insulation is not damaged, I agree with the others above.
 
jusme123 said:
IMHO, I'd rather see the damaged clear coat wire terminated than to add a splice on a larger feeder wire, thereby creating a fail point.
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:thumbsup:
iwire said:
Not even worth taping, we are not really talking about the insulation as mush as a slick cover that provides the gas and oil resistance of THHN / TWWN.
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Only reason to fail is if it is in an application that needs to be gasoline/oil resistant.
 
If you have concerns that it could be more then just the outer nylon coating being damaged, you could maybe at least have them meg the conductors and go wherever you go from those results.
 
pv_n00b said:
I was inspecting an electrical installation and one of the 350MCM conductors on a long pull had the outer covering skinned off for about 2 ½ ft in the panel where it was terminated. This is the part of the covering with the conductor information printed on it, the next layer down looked fine. I expect that the covering might have a few pull marks on it but not look like a snake shedding its skin. Is this a valid reason to reject that part of the installation? The contractor agreed to splice in a new section of conductor and that the way it was damaged represented poor workmanship on their part.
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do a mega test if you not sure,

Sent from my SM-G935V using Tapatalk
 
Here is an answer to this question given by UL-- taken from this site

A Type THHN wire is comprised of three basic parts, the conductor, PVC insulation, and a nylon jacket. Each part has a specific use. Damage to the nylon jacket only, does not constitute damage to the insulation. The nylon jacket does provide mechanical protection to the insulation during and after installation and also provides gasoline and oil resistance for the wire. The question concerning replacement of the damaged wire can only be answered by visually examining the wire to understand the extent of the damage; and if the PVC insulation is damaged, or if the conductor is exposed to gas and oil, then replacing the wire may be necessary.
UL certifies (Lists) THHN conductors under the product category Thermoplastic- Insulated Conductors (ZLGR), located on page 491 of the 2013 UL White Book and can also be found in UL’s Online Certification Directory at www.ul.com/database and enter ZLGR at the category code search field.
THHN conductors that are certified (Listed) under (ZLGR) are evaluated for compliance with the Standard for Safety for Thermoplastic-Insulated Wires and Cables, UL 83. UL 83 requires THHN conductors to be provided with a nylon jacket extruded tightly over the insulation with a minimum thickness of 4 mils for 14-10 AWG conductors and thicker for larger conductors.
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I agree that there is nothing to repair, and that a splice would add an unnecessary fail point to the installation.

I myself would not tape it, however to those who said that tape would make them suspicious: Around here it is common practice to red and blue tape the B and C legs of a 3-phase installation. Would that make you suspicious of what's underneath ?
 
flashlight said:
however to those who said that tape would make them suspicious: Around here it is common practice to red and blue tape the B and C legs of a 3-phase installation. Would that make you suspicious of what's underneath ?
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Not in the least because I would know way it was there.

On the other hand black tape 3' away from the terminal screams damaged insulation to me. :)
 
Thanks for the responses. I let the installer know I will pass it the way it is. It's still a poor way to leave the installation though. They could have pulled a few more feet of conductor and had a clean section all the way to the terminal. It's a several hundred foot underground run though, if it were shorter I would have them replace it based on NEC 110.12.

JFletcher said:
"Neat and workmanlike" is not enforceable. the rest of 110.12 or other articles may come into play for damaged insulation, which may be the result of other code violations, like conduit w/ sharp edges, lack of bushings, too many bends, pull boxes sized wrong, and so on.
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Why is 110.12 not enforceable? It's part of the NEC and it states, "Electrical equipment shall be installed in a neat and workmanlike manner." Seems as enforceable as any other provisions, and I have seen AHJs enforce it. I'm interested in your rational.
 
pv_n00b said:
Thanks for the responses. I let the installer know I will pass it the way it is. It's still a poor way to leave the installation though. They could have pulled a few more feet of conductor and had a clean section all the way to the terminal. It's a several hundred foot underground run though, if it were shorter I would have them replace it based on NEC 110.12.



Why is 110.12 not enforceable? It's part of the NEC and it states, "Electrical equipment shall be installed in a neat and workmanlike manner." Seems as enforceable as any other provisions, and I have seen AHJs enforce it. I'm interested in your rational.
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NFPA's own internal (but public) style guidelines state that such words as neat and workmanlike are so vague as to be generally unenforceable. But they are enshrined in existing Code and so remain unchanged while added new language tries to do better.
Note that this sense of "unenforceable" refers to holding up in court or leading consensus standards on what they do and do not require, not whether a given AHJ can interpret them as they will.
 
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