Grounding old outlets


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Old 12-14-07, 03:40 PM
W
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I have a similar situation. My house is a ranch with unfinished basement so I think I would be able to drill holes up through the floor and run a bare ground wire from the receptacle,down through the hole, and off to ground. My breaker box has a bare ground wire that runs from it across to the other side of the basement where it is connected to the incoming water pipe. Can I hook the new ground wires to this wire at the closest points possible, which would save a lot of copper, or go to the box or the pipe with each ground wire. Also, is there a device that tells you the quality of a ground in a receptacle? I bought one of these Sperry three prong testers and it says it does not indicate quality of a ground or reversal of grounding and grounded conductors. Thanks much for any help and Happy Holidays! Walt
 
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Old 12-14-07, 03:49 PM
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Depends on where you are, and you didn't put your location in your profile.

Fussy people might say no to your plan. But to me it seems to conform to the code. The grounding wire of which you speak (running from the panel to the inlet of the metal water pipe) is part of the grounding electrode system, and you can legitimately connect equipment grounding conductors to it.

I don't know of any practical device to tell you the quality of the ground. As you say, the little tester you have can be fooled by any number of bad and completely ineffective grounding mechanisms. Some people like to connect a load (such as a high-wattage light bulb) between hot and ground and see if it burns to full intensity. If you do this, use the highest wattage bulb you can find (or several such bulbs in parallel), and be careful enough not to kill yourself. However, even this won't identify a bootleg ground (a connection outside the panel between ground and neutral), or a ground that illegally (in the USA) uses a water pipe as part of the connection. You can probably identify a bootleg ground by disconnecting the circuit neutral in the panel before conducting the light-bulb test I mentioned.

BTW, if I had my way, the forum wouldn't let people post a question until they had entered a location in their profile. But alas, I rarely get my way.
 
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Old 12-15-07, 05:56 AM
W
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Hopefully the location thing (Midwest USA) is fixed-we'll see when this posts. Thanks for the help - should I get 12 or 14 GA bare wire for the ground? Also, I assume they make small clamps so I can hook the wires together without having to cut the main ground wire????
 
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Old 12-15-07, 08:26 AM
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Do Not Cut

DO NOT CUT the ground wire going to the water pipe. That wire must be continuous from the panel to the pipe. They do make clamps that are used to bond rebar in concrete but I'm am not sure if they come small enough. Your beat bet would be to use split bolt connectors. You can find them at most big box stores. Just make sure they are rated for the size wire you are using.

Heres what they look like:
http://electrical.hardwarestore.com/...onnectors.aspx

Just take off the nut and spacer, slip it on your main ground, put on spacer, put new wire on, reattach nut and tighten.
 
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Old 12-15-07, 03:31 PM
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You can use #14 if the breaker/fuse is 15 amps, or #12 if the breaker/fuse is 20. I'd probably just buy a roll of #12 and use it for everything (20 amps or under).
 
 

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