I was adding another circuit for a bathroom which required me to remove the breaker box panel for the first time. I notice while looking inside the breaker box; I spotted a red copper ground wire (like the copper wire heated up and discolored) this is a 12/2 cable that runs outside underground about 90ft. to a pool GFCI outlet. I was curious about this; so I shut the 20A breaker off and disconnected the ground wire from the neutral busbar and I saw a faint arc between the ground wire and busbar (I did this with the power off to that circuit). So I put a multimeter across the ground wire and busbar; it read: 47.3 volts. Any Ideas?
The Neutral (white) and Hot (black) wires in this cable look fine and I checked the wiring at the GFCI outlet box at the pool and the ground wire is very red at that end.
I never had this breaker trip or any other weird problems; the GFCI outlet works fine. Could lightning struck the pool at one time?
You had to have read the 47.3 volts with a digital multimeter. Disregard almost anything a digital multimeter tells you during troubleshooting of electrical power systems as they are too sensitive to stray voltages on disconnected wires to be of any use. The neon test lights are almost as bad. Use an analog meter or incandescent test light instead.
If there is any significant current leakage to the ground wire you will just have to disconnect things until it goes away to find the source. I do not believe you have a problem there, but I could be wrong.
The discoloration of the ground wire is very unlikely to be due to any overheating without other supporting symptoms. I have found some cables with discoloration on bare or insulated wires when new. Most of the wires are nice and shiny, many are dull, and some are really grungy with plastic stuck on them.
Your situation is definitely worth checking out, but from your description I personally do not think anything is wrong. If you are unsure you probably should have someone else look it over.
It's a violation of electrical code to have a red wire for a ground. It must be green. Remove it and replace it, or just paint it green and put it back.
Sorry I can't address the original post. My server did not deliver it.
The code requires green or green with yellow stripe, or bare. Where I come from people don't worry too much about the color. Black is common with a little green tape at both ends for identification. The color is not your main problem.
You say you have 47.3 volts between the ground wire and the busbar (assuming you meant the grounding bus bar or neutral bar at first means of disconnect). That could be a problem, especially since it is going to the pool.
You want an electrician to check it and a good one that really understands grounding. You see when large spaces are involved between points , there will be differences in voltage. Electricity exists everywhere. There are chemically induced currents , rf currents, all sorts of currents going to ground. Very often there is a potential voltage between the ground of one space and the ground of another. Systems over great spaces have grounding grids to keep these transient currents drained one into the other and in balance.
A few volts of potential is very common, but you note 47.3 volts. That is some heavy voltage around a pool. It could just be some low amp capacitance, but that should drain away quickly upon grounding and take time to build back up. The indication is there is a ground fault from some source near the pool or passing through the area. You need to find what is causing that and have it repaired.
Because your GFCI doesn't trip does not mean you don't have a problem. The individual GFCI works like this: The current that goes out the black wire and comes back on the white wire (changing directions 60 times per second) is measured. So long as both measurements remain within a certain tolerance of each other (black wire vs. white), there is no indication of a ground fault....for that circuit. If you have current flowing on the ground wire....that would indicate either the GFCI is not working.......or the ground fault is from a source other than the GFCI. That other source is using the ground path of the ground wire. Either way it could be dangerous.
This one could present a head scratcher for even the best of electricians.
As I read it, it sounds like the ground wire is bare copper, that has annealed somewhat, and has taken on a redish tinge, and is not a wire insulated with red insulation.
I agree that is is a problem, and should be checked.
40+ volts different between a buried conductor and the building's earth ground is too much. And the GFCI does not trip (this assumes GFCI is in breaker box - not at outside receptacle)? That breaker box GFCI action means 90 feet of black and white wires are not part of a circuit that creates a rather unacceptable 40+ volts. How is earthing for that breaker box? Is it securely connected to a nearby and properly installed earthing electrode? Is a second ground wire connect to where cold water pipe enters building? These missing ground wires might mean transient currents has to find earth via buried 90 foot conductor and have now blown a hole in cable's insulation jacket.
For some reas> I was adding another circuit for a bathroom which required me to remove
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