Floating ground ?

[earlyfilm]

Originally Posted by maxhifi

3. Add a ground connection to specific existing outlet. Get an appropriate length of #14 XLPE wire, and connect it from the third prong of the specific outlet being grounded back to a solid ground, such as the electrical panel enclosure, or a copper water pipe.

Some locations require a grounding wire at the utility box and nowhere else. I got in a fight with the inspector in Memphis, because I grounded our washer and dryer to the copper cold water pipe instead of to the central ground. (Our washer and dryer were in an unheated, unfinished, concrete-floor utility room outside of the back of our house.) I did this because if something fails and the ground wire becomes hot and I wanted no possibility for a shock in this potentially wet area.

I then suggested to the inspector that I tie both together, and was told specifically that it was not permitted.

James

[maxhifi]

Originally Posted by earlyfilm

Some locations require a grounding wire at the utility box and nowhere else. I got in a fight with the inspector in Memphis, because I grounded our washer and dryer to the copper cold water pipe instead of to the central ground. (Our washer and dryer were in an unheated, unfinished, concrete-floor utility room outside of the back of our house.) I did this because if something fails and the ground wire becomes hot and I wanted no possibility for a shock in this potentially wet area.

I then suggested to the inspector that I tie both together, and was told specifically that it was not permitted.

James

Yes, if you ground at more than one point you might create a ground loop, and get circulating currents. I said to ground to a pipe because realistically, it may be totally impractical to run a wire all the way back to the panel and there could be a water or radiator pipe staring you in the face. Of course I am assuming your water pipes are all metal and are grounded too, but given the age of the house it's probably a reasonable assumption.

Electrical code is designed in such a way as to be fool proof, but it is far from the only way to make something safe and reliable. Of course I am making the assumption that the pipe is a good ground, but it's not hard to verify if it is. Look at how wiring is done in Europe... much of it would NEVER pass inspection in north America but you don't hear scary statistics about electrical fires and electrocutions in Europe.

[old_coot88]

Some really scary stuff like house fires was recounted in the aluminum wiring fiasco.