Black wires

Why are the copper wires black. If they where overheated the insulation would be melted. It looks like a painted material. Seems kinda strange.

I have never seen the wires black at the terminal connections before.



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hmmm…never seen this before myself and I have seen many things electrical in my time.

Now…since you looked at it more close than I can…is it possible they were dipped in Anti-Oxid…I know…if they are copper…no point but you never know.

I will have to do some research on this…never actually seen “BLACK” coated conductors…unless something was applied to them…maybe …lol…maybe someone confused the re-identify requirement of the insulation to mean the conductor itself…lol…who knows.


The only Anti-Ox. paste I observed was at the main.
Now I know it is strange if you have’nt seen this.
Would you recommend having the panel evaluated?

Thanks for the reply.


Been a strange day.

Had a radon test Addendum that was constant 1.5-2 for 48 hours then spikes to 7.9. I sent them my free kits that I received from being a Nachi member.


Well…My electrical experience and knowledge usually get me by rather nice…But if all the conductors are the same and no signs of damage to the insulation on the conductors I would probably not write it up.

Consistancy is important…if they are ALL this way I might just have to call the electrician who did it and ask him out of the fact I just would have to know…since I have never seen it before.

If you have NO other issues in that panel in regards to bonding and terminations and so on…I am not sure I would suggest it be evaluated…IF you have other issues that need evaluation then most certainly post that you have no idea why they are black…and HOPE you get someone who has seen it before when they come out.

If I came out…I would probably remove a few, scrape the conductor to see if it is coating, dis-coloration and make my determination at that point…again one of those things I have to see and “smell” to give a real comment on because I have never seen “ALL” blackened wires before other than from scorching and so on…and then you should have insulation damage as well.


Is this panel is a chlorine environment by any chance, I have heard of certain gasses turning copper a “black” color before but have never seen it…Are the SE conductors this color as well?

Is “sulfer water” common in your area? The H2S gas given off from this type of water will cause all exposed copper to turn black in a short time.

I believe this is an Environmental thing and not an electrical related thing…I would probably not write it up.

Sewer gases will turn the copper black.

Paul, I will vote for sulfur too. We have sulfer in the water and copper pipes turn coal black.

Yeah…I believe the “SULFER” water is the culprit…