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Posted by Bob Vaughan on July 17, 2006, 1:32 am
>
>> wrote:
>>
>>>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?
>>
>> 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.
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.
>
>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.
I agree that is is a problem, and should be checked.
>
>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.
>
>Good luck!
>Randy R. Cox
>
>
>
--
-- Welcome My Son, Welcome To The Machine --
Bob Vaughan | techie @ tantivy.net |
| P.O. Box 19792, Stanford, Ca 94309 |
-- I am Me, I am only Me, And no one else is Me, What could be simpler? --
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