Damage on romex sheathing , is electrical tape OK/to code to repair with?

[zappy]

Also a wire underneath has insulation damage. Thank you for your help.

 

[MarkyMarkNC]

Southwire guys say tape is fine to repair NM sheath. They even go so far as to say if you think you have a nick in the wires, it is best to strip back the sheath to check, and then tape back over it if they are ok. Nicks in the wiring insulation are a different story - replacement is recommended in that case.

 

[svh19044]

Electrical tape on the sheathing is fine, electrical tape as the conductor insulation is not fine.

 

[Stevareno]

Electrical tape on the sheathing is fine, electrical tape as the conductor insulation is not fine.

Even if the electrical tape is rated as such?


Same scenario, different situation. You're pulling a 4 wire 500 kcm service to a distribution panel 200 feet and you nick the insulation on one of the wires during the pull.
Do you just tape the nick, or do you pull out the whole run, replace the damaged wire, and then repull? :?

 

[svh19044]

Even if the electrical tape is rated as such?


Same scenario, different situation. You're pulling a 4 wire 500 kcm service to a distribution panel 200 feet and you nick the insulation on one of the wires during the pull.
Do you just tape the nick, or do you pull out the whole run, replace the damaged wire, and then repull? :?

I'd imagine that would depend on your PM, the EE, or whoever else is in charge. A splice box would probably be better than the tape to them, but they would prefer the new run.

 

[buddhakii]

How about some heat shrink

 

[ActionDave]

....Do you just tape the nick, or do you pull out the whole run, replace the damaged wire, and then repull? :?

Well not just tape. You gotta use some Scotch Kote and maybe some rubber splicing tape along with the vinyl tape.

 

[elohr46]

If you can butt splice a conductor and tape it you should be able to do the same with a nick in the conductor.

 

[Dennis Alwon]

From Southwire-- Jacket Repair Methods

Hand-wrapped tape repair

A very basic jacket repair method is to hand-wrap the cable with a flexible, self-bonding rubber tape, then a vinyl insulating tape. A typical application consists of two layers of rubber tape, overlapping half the width of the tape. Cover the repair with one layer of vinyl insulating tape, again overlapping half the width of the tape.

 

[dhalleron]

I can't quote a code requirement, but I don?t think it would be considered a splice if the wire is unbroken. As long as I could repair the insulation as good or better than original I would not worry about adding a splice box.

I have buried taped up romex in a wall and did not worry about it. And I do not like to hide things that might come back to bite me later. I do not want to read about one of my projects burning down on the news.

 

[cowboyjwc]

Well not just tape. You gotta use some Scotch Kote and maybe some rubber splicing tape along with the vinyl tape.

Three wraps of 3M tape is all that is needed.

Now as an inspector, I would probably make them megger it out. If you nicked it once there's a good chance you nicked it again.

 

[btharmy]

You can always cover the scotch 33 with some apropriately colored phase tape. Orange for #10, yellow for #12. Just for looks, and to avoid any un-wanted attention.

 

[ActionDave]

Three wraps of 3M tape is all that is needed.

Now as an inspector, I would probably make them megger it out. If you nicked it once there's a good chance you nicked it again.

Scotch Kote always man. Just because you don't need doesn't make it less magnificent.

 

[ZZDoug]

Three wraps of 3M tape is all that is needed

Says who? It's always been my understanding that it must be equal too or better than the original insulation, but who is to say what that is? I doubt if 10 wraps would be sufficient for most inspectors, not to mention engineers. But I guess technically the determination would have to be from the manufacturer, which you will almost never have. Or is there documentation or guidelines from wire manufacturers about this?

I have seen repaired skinned insulation like you say, although probably due to paranoia it was more like 6 to 10 wraps of 33, and it always megged out more than fine. But I've always wondered about the long term reliability of tape as compared to solid uniform insulation, especially if it's wire that's subsequently going to be pulled through conduit. If you are going to do such a thing at the very least use good quality brand name tape.

 

[Little Bill]

Says who? It's always been my understanding that it must be equal too or better than the original insulation, but who is to say what that is? I doubt if 10 wraps would be sufficient for most inspectors, not to mention engineers. But I guess technically the determination would have to be from the manufacturer, which you will almost never have. Or is there documentation or guidelines from wire manufacturers about this?

Cowboy is an inspector!:slaphead:

I have seen repaired skinned insulation like you say, although probably due to paranoia it was more like 6 to 10 wraps of 33, and it always megged out more than fine. But I've always wondered about the long term reliability of tape as compared to solid uniform insulation, especially if it's wire that's subsequently going to be pulled through conduit. If you are going to do such a thing at the very least use good quality brand name tape.

See Dennis' post #9

 

[ZZDoug]

Bill, I saw that Southwire webpage, but it's talking about "jacket" repair. Correct me if I am wrong but isn't the jacket an outer covering for a cable assembly, as opposed to the actual wire insulation? Notice for example how Southwire says "the jacket isn’t really part of the insulation system of the cable. The jacket is strictly for mechanical protection and to keep out moisture". And what about other brands? Anyway I was thinking more about actual individual wire insulation. There are shrink kits available that are listed for underground repair and can be used on individual conductors, but we are talking here about tape on individual conductors, the most common example I suppose would be inside conduit. But as I said, the tape has to be applied before you pull the wire in, which to me presents a real concern. I've never seen any definitive information that covers this, I mean from a "legal" perspective (manufacturer info, listing, etc).

 

[Dennis Alwon]

Here is what I have done. If it is just the jacket I slide a small piece of a jacket from a scrap piece around the infected area. I then use tape to hold the extra jacket to the cable. If the wire is just nicked and not damage you could strip it back some wrap tape around the conductor and then proceed as above. Personally if possible I would pull a new piece.

 

[cowboyjwc]

Says who? It's always been my understanding that it must be equal too or better than the original insulation, but who is to say what that is? I doubt if 10 wraps would be sufficient for most inspectors, not to mention engineers. But I guess technically the determination would have to be from the manufacturer, which you will almost never have. Or is there documentation or guidelines from wire manufacturers about this?

I have seen repaired skinned insulation like you say, although probably due to paranoia it was more like 6 to 10 wraps of 33, and it always megged out more than fine. But I've always wondered about the long term reliability of tape as compared to solid uniform insulation, especially if it's wire that's subsequently going to be pulled through conduit. If you are going to do such a thing at the very least use good quality brand name tape.

http://multimedia.3m.com/mws/mediawebserver?66666UuZjcFSLXTtMxMynxs6EVuQEcuZgVs6EVs6E666666--

My bad, what it says it 2.5 over lapped wraps.

 

[ZZDoug]

Thanks for that link John, it's documentation for exactly what you were saying. For those who can't make the link work, it's just a pdf brochure for 3M Super 88, says it's UL listed as "insulating tape" and requires 2.5 (overlapped) wraps.

 

[kwired]

If you can butt splice a conductor and tape it you should be able to do the same with a nick in the conductor.

You can tape a butt splice but you must make it in an accessible junction box or other enclosure, and not just bury it in a wall.

If underground or wet locations you better use more than just tape - especially with aluminum conductors. This is where the Scotchkote is handy.

OP is talking about NM cable though so it is not allowed underground or in wet locations.