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Suspicious ground wire...

I've noticed that one of the electrical conduits in our basement has a solid wire (14-gauge, it looks like) wrapped around it, and the other end is wrapped around the cold water pipe at the point where it enters the house. A do-it-yourself grounding technique made by a previous owner, perhaps? The conduit itself doesn't have a third ground wire, the ground terminals on the switch and outlets are just wired to the metal boxes.

With the exception of the wire running between the conduit and the water pipe, I'm assuming that the conduit isn't grounded, because much of the wiring in the basement is still old "knob and tube" wiring. So now I'm looking at this makeshift ground connection, saying to myself, "This CANNOT be safe." I'm not sure what the electrical regulations say about this kind of thing, but does anyone know if my suspicions are correct?

Reply to
Equillibrius
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Safety would depend on the quality of the connections and the electrical integrity of the water pipe (no plastic) but it certainly is not code.

Reply to
Greg

Perhaps a pullwire left in for the future?

Bob AZ

Reply to
RWatson767

That is a most unusual situation with knob and tube and conduit in the same house.

You can run romex in a basement. I wonder why the conduit is there in the first place?

If it turns out to be unsafe you might just consider fixing it with romex. It is a much cheaper solution than running conduit.

Reply to
Kilowatt

I guess I forgot some details in my first post.

The conduit in question runs along a brick wall and serves two fluorescent light fixtures and some receptacles for a utility desk. I think it was added some time after the house was built (early 40s), and I'm guessing whoever installed it didn't want to punch holes in the brick.

Reply to
Equillibrius

The conduit can serve as the ground itself without having a green ground wire in the conduit (if the conduit is bonded at the panel or starting point for the pipe). You can then bond to the box like you described he has done. I am guessing if he took the time to bond to the box like you say that the open wire in question might just be used to keep another pipe from vibrating or just to tie up something.

The only way to know for sure is try to figure out another reason the wire is there.

I can think of no reason why anyone would want to try to ground a system the way you describe.

Reply to
Kilowatt

As stated before, the conduit (we're assuming EMT or the like) IS a grounding conductor IF it originates in a grounded box. Its not uncommon with a house old enough to have knob and tube to have a few 'generations' of wiring, since electrical requiements were pretty basic back in those days. Its also not uncommon for weekend warriors to 'fix' a perceived problem that does not exist. In other words...disconnect the wire in question and check for continuity between neutral and ground @ one of the recepticals served by the conduit... if you have continuity, you are reading the neutral bond @ the panel and you are most likely ok.

john

Reply to
John Ray

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