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lapriest
Dec 21, 2007, 11:08 AM
My home was built in 1959, and I have a fuse box. I don't have ground wires to all of my wall outlets. The only wall outlets with ground wires have major appliances connected to them. I purchased several wall outlets with three prongs to replace a couple of two prongs. How do I add a ground wire to my outlet?

I just checked a couple of my wall outlets that have a three prong recept. I saw two large cables coming into the box. Each had a black & white wire from each cable. Both white wires were connected to one side of the recept. And the two black wires connected to the other side. Does that mean it should be grounded? I checked a couple of my wall outlets that have two prong recept. I saw only one cable with a black & white wire that was connected to opposite sides of the recpet. Can I just tie an insulated wire from the metal conduit box to the ground screw on a three prong recept. To make it a grounded? Or is that unsafe and aagaist regulation?

tkrussell
Dec 22, 2007, 07:59 AM
I left this for others to see what would be the answer, I guess I will need to offer the advice.

The traditional method is using a GFI breaker to protect the entire circuit if practical or necessary.

Or use a GFI receptacle at the beginning of a circuit to protect other downstream outlets, if the wiring is daisy chain.

If the wiring does not go from outlet to outlet, then either each outlet needs to be GFI, or you have no choice but to use a breaker.

Each three wire outlet with no ground must have a label "GFI Protected" and No Equipment Ground", these labels often are provided with the GFI receptacles.

There is a little known exception that does allow a separate green wire to be installed from the green screw of a 3 wire outlet back to a equipment ground bar or a grounding electrode. There are conditions that a DIY'er will may not be able to understand, and accomplish, and this method is often not allowed by inspectors because of these conditions.

For these reasons, you can look back at many other of my answers that I do not acknowledge this method, or mention that it is allowed. This may confuse others that have read my previous answers, oh well, I have my reasons. When they become an expert in this field, they can answer as they see fit.

And the thinking is if a separate wire can be installed, then there is no reason a new 3 wire cable cannot be run, which is the preferred solution.

So, you may use a GFI breaker, GFI receptacle, or run new 3 wire cable, as I will not explain the conditions for the exception.

labman
Dec 22, 2007, 08:42 AM
You can see I have been around here much longer than tkrussell. When I first came here, we didn't have anybody providing good answer in E&L . I know enough to provide safe and workable answers in many of the easier cases. Since we have somebody that can give good answers to even the trickiest questions, I have cut back in E&L answers. While we have some other people giving good answers, there are some more that would do better to become an expert in the field before they answer more questions. I see no value in a prompt answer that may or may not be right. Unfortunately, the green and red boxes have completely failed in guiding people in who to trust. Note in this E&L question, I have more than tkrussell, but know much less.

tkrussell
Dec 23, 2007, 07:57 AM
In my answer to your PM I asked you to post your question here, and I would provide the answer.

I will post my answer even thou you have not asked yet, I want to keep up with questions and keep my work load up to date.

My answer is:

What kind of cable do you have? If is is BX with metal sheathing or casing, then that is the ground, and all you need to do is install a 3 wire outlet, with a green jumper from the green screw to a green screw driven into a machine threaded hole in the metal box.

If you read 120 volts across the black wire and the metal box or metal sheathing of the cable, then you have a ground.

They sell these jumpers already with the green screw at electrical supply stores.

The double white and blacks mean that is is wired " daisy chain" from one outlet to another. That does not mean anything regarding grounding.