Electrical circuit question
#1
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Electrical circuit question
I have a circuit at my home with a couple of ground faults and then the usual stuff lights , receptacles,, and switches.
A few weeks ago the breaker in the main panel tripped and I could not reset it.
I checked both ground faults and I could tell that they were burned.
So I replaced them with new, but the problem continued.
I was checking this weekend and found a loose hot wire on one of the inside regular receptacles, fixed that, then I checked the outside deck light and saw that a lead to the light was burned and I could see copper so I am guessing that is where my problem is. Which leads to my question. There are two 14-2 cables coming into this box, I have two outside lightson this switch so one 14-2 must continue on to the other outside light. So I am wondering about the condition of the two 14-2 cables. They do look okay as far as the black insulation goes but there must be a clear film of some sort that maybe protects the insulation and this clear film is loose andis able to be pealed right off, So I am just wondering if they got hot and maybe should be replaced just to stay on the safe side?
A few weeks ago the breaker in the main panel tripped and I could not reset it.
I checked both ground faults and I could tell that they were burned.
So I replaced them with new, but the problem continued.
I was checking this weekend and found a loose hot wire on one of the inside regular receptacles, fixed that, then I checked the outside deck light and saw that a lead to the light was burned and I could see copper so I am guessing that is where my problem is. Which leads to my question. There are two 14-2 cables coming into this box, I have two outside lightson this switch so one 14-2 must continue on to the other outside light. So I am wondering about the condition of the two 14-2 cables. They do look okay as far as the black insulation goes but there must be a clear film of some sort that maybe protects the insulation and this clear film is loose andis able to be pealed right off, So I am just wondering if they got hot and maybe should be replaced just to stay on the safe side?
#2
The film is normally a little flaky. Your problems were probably loose connections. Any backstabs should be moved to the screws. Backstabs can be unreliable. Note: GFCI receptacles are back wired not back stabbed (or side wired). Those are reliable connections and just need the screw tested for tightness.
Terminology note: GFCI is the more correct term not "ground fault" which is a potentially dangerous electrical problem.
Terminology note: GFCI is the more correct term not "ground fault" which is a potentially dangerous electrical problem.
#3
Can you post a picture ? THHN as a nylon overcoat. I am not sure if that is your concern. Is your wiring in conduit?
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The one and only switch controls two lights so it passes through the box where i encountered the issue, they installed a couple small leads to connect to the light, one of the leads is pictured and if it works out right you can see the burned spot, the other is the clear film that I peeled off the one of the 14-2's that run through the box

#5
Looks like the nylon overcoat. Loss of it does not affect the insulation value.
Burned spots on the insulation need to be repaired. Heat shrink tubing is a good method.
Burned spots on the insulation need to be repaired. Heat shrink tubing is a good method.
#8
Don't peel off the transparent overcoat except at the end to expose enough copper to make the connection with. The underlying insulation is not as physically robust as on wires that do not have the transparent overcoat.
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I have a circuit at my home with a couple of ground faults...
Also, as Chandler points out, "14-2" refers to a CABLE, not individual conductors which is what you pictured. A cable is defined as two or more conductors with an overall jacket.
You really need to get a book on DIY wiring so you can learn the proper wording. I recommend Wiring Simplified and it is available for about ten dollars, more or less, from on-line booksellers as well as big box mega-mart homecenters and often corner hardware stores. At the homecenter it is more likely to be in the electrical aisle than in the books and magazines section.