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When replacing a receptacle in an older home that has a two wire system, {no ground} a GFI receptacle is to be used and label it no ground as I read the code. If I'm not correct on this please set me straight. I have another question though that I'm trying to work out in my head. Why is it your not allowed to connect the ground to the neutral in that same box with the new GFI receptacle? Seems like that should work fine. Thanks for reading.
 

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why install if it is not going to do its job in the first place. Doing what you said will make it work but I'am not a sparky so I dont know if this is safe.
 

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There are three wires in modern 120v wiring: Their technical names are the ungrounded, grounded and grounding. You probably know them as 'hot', 'neutral' and 'ground'.

The 'hot' and 'neutral' differ from the 'ground' in that they both are considered 'current-carrying' conductors. Meaning they carry power. The 'ground' only does in a fault situation such as a short.

If you were to tie the 'neutral' and 'ground' together at an outlet in a box, you basically turn the exposed metal parts of whatever you plug in into a current-carrying conductor. You effectively create a potential of 120v to ground.

If, for whatever reason, the 'neutral' of your wiring should become disconnected, everything in your house......... your fridge, computer, TV, everything plugged in that has a ground pin on the end of the cord....... a 'hot' conductor. All that is needed is you, or your wife, or your kids, or your neighbor, to complete the circuit by touching one of those items while grounded (touching a sink with metal piping, standing barefoot on the ground or concrete floor).

And trust me, this will not feel the same as simply creating a circuit by getting between a hot and neutral. In this case, the pain you feel is related to the resistance of your body.

But when you become part of the faulted circuit created by your 'jumper' or 'bootleg ground', the pain you feel is related to the resistance of the entire circuit and the loads that are on it. The resistance of the circuit is far different than that of just your body alone and it will hurt a whole lot worse.
 

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Head Grunt
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What kind of wire is it? It is fairly common to see where guys in the past coiled the ground around the casing and either tried to clamp it in the box or just left it outside the box where it cannot be seen. I would at least inspect the main panel itself to see if all or that particular circuit is grounded. If so then remove the box from the wall, pull out the ground and re-install the wire using an old work box. That would make your GFCI functional and up to code.
 

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Project Manager HFH..
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There are three wires in modern 120v wiring: Their technical names are the ungrounded, grounded and grounding. You probably know them as 'hot', 'neutral' and 'ground'.

The 'hot' and 'neutral' differ from the 'ground' in that they both are considered 'current-carrying' conductors. Meaning they carry power. The 'ground' only does in a fault situation such as a short.

If you were to tie the 'neutral' and 'ground' together at an outlet in a box, you basically turn the exposed metal parts of whatever you plug in into a current-carrying conductor. You effectively create a potential of 120v to ground.

If, for whatever reason, the 'neutral' of your wiring should become disconnected, everything in your house......... your fridge, computer, TV, everything plugged in that has a ground pin on the end of the cord....... a 'hot' conductor. All that is needed is you, or your wife, or your kids, or your neighbor, to complete the circuit by touching one of those items while grounded (touching a sink with metal piping, standing barefoot on the ground or concrete floor).

And trust me, this will not feel the same as simply creating a circuit by getting between a hot and neutral. In this case, the pain you feel is related to the resistance of your body.

But when you become part of the faulted circuit created by your 'jumper' or 'bootleg ground', the pain you feel is related to the resistance of the entire circuit and the loads that are on it. The resistance of the circuit is far different than that of just your body alone and it will hurt a whole lot worse.


I would think an electrician would know this very basic explanation.
I would not call myself an electrician as to not disrespect a real sparkie.
But I know this stuff and much more having worked side by side with an EC on a remodeling crew for six years and it helps me in my role as a GC....

Kinda scary that someone calling them self an electrician would ask this question.....just sayin'
 

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Discussion Starter #8
Thanks for the replies

I certainly understand why the ground cannot be tied to the neutral now. I should have been able to figure that one out myself. But anyhow Thanks. I rewired the existing GFI recpts. today with 12/2 wground so there is a ground wire now.
 

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Project Manager HFH..
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I certainly understand why the ground cannot be tied to the neutral now. I should have been able to figure that one out myself. But anyhow Thanks. I rewired the existing GFI recpts. today with 12/2 wground so there is a ground wire now.
:blink:
 

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I certainly understand why the ground cannot be tied to the neutral now. I should have been able to figure that one out myself. But anyhow Thanks. I rewired the existing GFI recpts. today with 12/2 wground so there is a ground wire now.
I must echo Jumbojack.

This is pretty basic stuff for an electrician. I'm guessing you are not licensed.
 

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Thank God for you real sparkies.:thumbsup:

480 u da man!!:notworthy:notworthy

Far too many guys out there that think twisting on a wire nut makes them an electrician:whistling
 

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Scary

It's really scary that the guy would call himself an electrician. I'm not an electrician but I have educated myself on electricity and even I knew the answer to his question.
:rolleyes:
 

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I was an "electrician" 5 years ago and I didn't know much about 3-phase wiring. Just sayin...
You mean laborer working for an electrical company?;) I learned about 3 phase a fair amount....in school.....studying electrical...
 

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#1 stunner
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We are all here to learn............ If we didn't ask questions how will we ever learn anything?
I mean woodchuck thought GFCI had to have the grounding conductor fastened to work correctly, not picking on you: just sayin.
 

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I own stock in FotoMat!
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We are all here to learn............ If we didn't ask questions how will we ever learn anything?
I mean woodchuck thought GFCI had to have the grounding conductor fastened to work correctly, not picking on you: just sayin.
.......
Um yeah Hi.My name is Jack and I'm a surgeon.I was wondering if any of ya'll could help me with a question....
I have a patient that need's his appendix removed.Any hoo I can't remember what side it is on..I am pretty sure but I wanted to double check.....

Thank's in advance.

Dr.JumboJack
 
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We are all here to learn............ If we didn't ask questions how will we ever learn anything?
They teach you in school.:whistling

I mean woodchuck thought GFCI had to have the grounding conductor fastened to work correctly, not picking on you: just sayin.
At first I thought that could be a US code thing because around here GFI are used in situations where ground wires aren't present and running a new wire is troublesome.
 
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