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  #1  
Old 09-23-2008, 05:45 PM
Una Persson Una Persson is offline
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How OK is it to replace ungrounded outlet with GFCI outlets?

I've read that as an alternate to re-wiring your entire house to get more protection (and a 3-prong adapter) at your outlets, you can safely (and under code) just replace each outlet with a GFCI outlet (or a central GFCI, I suppose). It seems to me that's cheating - is it? What level of safety does it provide using a GFCI on an ungrounded circuit versus a grounded circuit?
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Old 09-23-2008, 09:53 PM
Ed Zotti Ed Zotti is offline
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A GFCI and a grounded outlet do two different things and protect against two different scenarios, and one is not a replacement for the other. A grounded outlet protects against a short in the WIRING, specifically, a wire coming loose and contacting a metal electrical box or housing. If the box or housing is grounded, the fuse or breaker will blow and presumably you'll realize you have a problem. If this DIDN'T occur, anyone who touched the box or housing would get a shock - whether you've got a GFCI outlet is irrelevant. A GFCI outlet protects against a short (or more commonly a current leakage) involving YOU and an electrical device plugged into the outlet. If an appreciable amount of current flows from the appliance through you to an earth ground (presumably because your hands are wet - typically GFCI outlets are installed near sinks), the outlet trips. So, in the first scenario, the problem usually is a frayed or broken wire, whereas in the second, the problem is carelessness on your part, because you didn't dry your hands.
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Old 09-23-2008, 10:07 PM
elmwood elmwood is offline
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As far as buildings codes in the US go, the only acceptable way to replace a two-prong outlet with a three-prong outlet in an ungrounded circuit is a GFCI outlet. I wouldn't use them for every outlet if the entire house is ungrounded, though.

In my mid-century, where some outlets are grounded and others not, I replaced the old two-prong outlets with GFCI outlets. It's expensive, but it meets code. The tricky part is determining the polarity of the wires; color codes in the good 'ol days were much different than today, and the decades of dirt and nicotine that soaked into fabric insulation can make both wires look black. When you disconnect the old outlet, make sure you have a close look at the old outlet, and note what wire is hot. One advantage of a GFCI; if you reverse the wiring, the outlet won't work, period.

In Canada, it's acceptable to replace an ungrounded two-prong outlet with a three-prong outlet that had the ground hole plugged. This allows the use of Decora outlets and cover plates in ungrounded circuits. It's not kosher in the US, though; if you have ungrounded outlets and want to go Decora, GFCI is the only way.
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Old 09-23-2008, 10:13 PM
Una Persson Una Persson is offline
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So in other words, if I don't want to tear apart every wall in my house to re-wire every outlet, I can at least install GFCIs and get some additional protection against some faults, and meet code. Sounds decent to me for some outlets. And they're not that expensive any more, about $10 an outlet or something, right?
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Old 09-23-2008, 11:27 PM
elmwood elmwood is offline
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Quote:
Originally Posted by Una Persson View Post
So in other words, if I don't want to tear apart every wall in my house to re-wire every outlet, I can at least install GFCIs and get some additional protection against some faults, and meet code. Sounds decent to me for some outlets. And they're not that expensive any more, about $10 an outlet or something, right?
That's correct, although if you've got an ungrounded house, I'd look at rewiring if you plan on staying there.

GFCI outlets now cost about $12 to $15. Cheaper GFCI outlets may have passed UL tests, but reliability in the long run could be questionable. I prefer Leviton (usually made in the USA or Mexico) to Cooper or other manufacturers that outsource to China. GFCIs can go bad, so test them often.

EDIT: I don't think you have aluminum wiring in your house. If you've got ungrounded outlets, it tells me that they date to the 1950s and earlier, before aluminum was used in the late 1960s. Never, ever connect aluminum wiring to a modern switch or outlet; most are designed for copper wire only.

Last edited by elmwood; 09-23-2008 at 11:30 PM..
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Old 09-24-2008, 11:15 AM
Una Persson Una Persson is offline
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The house was built in 1960, and AFAIK has copper wire all throughout.

But in terms of grounding it, there's just no cheap or easy way to do that so it's not going to happen. There are a couple of grounded outlets that the previous owner made by running wires to the plumbing, but I thought that was a code violation. Add to this the fact that I can't even get an electrician to give me a quote... :/

I can't even say the people who built my house were cheaping out. Not only did they install all copper water and waste pipes, they used things like 28-foot 2x8's (yes, single pieces 26 feet long) for joists.
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Old 09-24-2008, 02:08 PM
gotpasswords gotpasswords is offline
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You can replace non-grounded receptacles with GFCIs, but you do need to add a "No Equipment Ground" label to them. References to the NEC are in italics below. And note the exception to new work. This workaround only applies to existing wiring. As soon as you add anything, you have to rewire the circuit with a ground.

Quote:
Under what condition can a two-wire receptacle be replaced with a three-wire receptacle, when no ground is available in the box?

A. Where no equipment bonding means exists in the outlet box, nongrounding-type receptacles can be replaced with [406.3(D)(3)]:

Another nongrounding-type receptacle.
A GFCI grounding-type receptacle marked "No Equipment Ground."
A grounding-type receptacle, if GFCI protected and marked "GFCI Protected" and "No Equipment Ground."
Note: GFCI protection functions properly on a 2-wire circuit without an equipment grounding (bonding) conductor, because the equipment grounding (bonding) conductor serves no role in the operation of the GFCI-protection device.

CAUTION: The permission to replace nongrounding-type receptacles with GFCI-protected grounding-type receptacles doesn't apply to new receptacle outlets that extend from an existing ungrounded outlet box. Once you add a receptacle outlet (branch-circuit extension), the receptacle must be of the grounding (bonding) type and it must have its grounding terminal grounded (bonded) to an effective ground-fault current path in accordance with 250.130(C).
(From http://www.mikeholt.com/mojonewsarch...s~20050510.php)
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  #8  
Old 09-24-2008, 04:29 PM
Una Persson Una Persson is offline
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I can see that my Thanksgiving holiday is going to be spent installing 30-40 GFCI outlets...fun for the whole family.
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  #9  
Old 09-24-2008, 05:38 PM
Ed Zotti Ed Zotti is offline
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Quote:
Originally Posted by elmwood View Post
One advantage of a GFCI; if you reverse the wiring, the outlet won't work, period.
What kind of GFCI outlets are you using? I have a new one, purchased recently, still in the box. I tested it just now in the basement. It works fine either way - white to silver terminal, black to brass, or the other way around. Perhaps you're talking about getting the LINE and LOAD terminals mixed up, which is a different matter.
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Old 09-24-2008, 06:26 PM
Ed Zotti Ed Zotti is offline
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Quote:
Originally Posted by Una Persson View Post
I can see that my Thanksgiving holiday is going to be spent installing 30-40 GFCI outlets...fun for the whole family.
I get uncomfortable when I hear talk like this. For one thing, you're talking about a major project. Have you done anything like this before? Also, to repeat what I said earlier, a grounding outlet and a GFCI outlet do two different things. If you install a GFCI outlet in an ungrounded box, the socket for the third prong won't be electrically connected to anything. I know the outlet will work and is allowed by code, but if you do the whole house this way your wiring will still be missing a major safety feature and whoever buys the place from you won't realize it. If it were my house I'd limit the GFCIs to the places where they're recommended, namely bathrooms, damp locations, etc.

BTW, I take it your house is wired with Romex with no bonding wire?
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  #11  
Old 09-24-2008, 07:25 PM
Una Persson Una Persson is offline
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Quote:
Originally Posted by Ed Zotti View Post
Have you done anything like this before?
Just replacing outlets? Yes. Is there more to it than that? And it's not so big a job as long as I do one outlet at a time and test each one as I go. I doubt I'll do more than 12-15 in truth before I get tired of it.

Quote:
I know the outlet will work and is allowed by code, but if you do the whole house this way your wiring will still be missing a major safety feature and whoever buys the place from you won't realize it.
Well, the house isn't going to be re-wired completely, and the way I see it the GFCI is safer than what I have now. Right now I'm using 3->2 prong converters for all my appliances, the new way I have no converters and at least I have GFCI protection. Also, I will be putting the little sticker on that says "No Equipment Ground". And I guess another thing is I have no intention of selling the house, but if I do, and forget to mention it, their home inspector can plug his little tool into the outlet (like I have) and see that there's no ground.

Quote:
BTW, I take it your house is wired with Romex with no bonding wire?
That's what it looks like, but I haven't checked all outlets.
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  #12  
Old 09-24-2008, 09:12 PM
Ed Zotti Ed Zotti is offline
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Quote:
Originally Posted by Una Persson View Post
Just replacing outlets? Yes. Is there more to it than that?
I'll e-mail you.
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  #13  
Old 12-11-2011, 11:50 AM
TransistorJunction TransistorJunction is offline
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Corrected information!

This post is over ten years old but I'm posting an update for anyone reaching it via a web search. Some of the information provided previously is incorrect. A GFCI works by constantly sensing the current running though both the hot and neutral wires. If there is even the slightest difference between the two, the circuit is shut off immediately.

Therefore if any current is flowing from the hot wire to ground instead of back through the neutral wire the power will be instantly disconnected. That is why no ground wire is needed.

Also, it is usually NOT necessessary to replace EVERY ungrounded outlet with a CFGI outlet. Typically several outlets are on the same circuit. As long as the FIRST outlet in the chain that has its power coming directly from the circuit breaker is a GFCI, then the rest of the outlets on the circuit AFTER the GFCI outlet are also protected by it.

This is why is is critical that ALL of the following be identified correctly:
1) Hot vs. Neutral wires

2) Line vs. Load wires (The wire coming IN from the source or previous outlet in the chain is the LINE, and a wire going out to the next outlet is the LOAD)

3) The FIRST outlet in a circuit must be determined, as that must be the one replaced with the GFCI outlet. The others can be replaced with regular three prong outlets (with no connection to the ground screw).

So use the money saved by not needing to replace every outlet with a GFCI and invest in a good meter or voltage detector. Turn the circuit breaker off and verify that every outlet you plan on replacing is unpowered. If not, then it is on a different circuit. Work on only one circuit at a time. Find ALL outlets on that circuit then disconnect ALL wires from each one (be sure the power is still off). If all wires on all outlets are not disconnected then there is the possiblity of power feeding back through the neutral and you will get misleading results (and possibily a shock from the neutral wire).

Make sure no wires are touching each other or anything else, and that all exposed wires are proected from childern, pets, etc. then have someone turn the power back on and find the ONE hot wire. This will be the HOT LINE for the FIRST outlet. Turn the power off again and connecte this wore to the HOT, LINE terminal. The corresponding wire will be the NEUTRAL LINE connection for that outlet. If there is another pair of wires at that outlet that go to the next outlet, connect these to the LOAD terminals, again observing which is hot and neutral.

Now the rest of the outlets on that brach circuit can be replaced with regular three prong oulets. There is no distinction between line and load on these, but be sure the hot wires (usually black) go to the darker of the screws (usually brass colored) and the neutral wires go to the lighter screws (usually silver coloered). If you look closely at an outlet you will see that one of the vertical slots is longer than the other. The hot is the shorter of the two.

In addition, as noted earlier, ALL outlets affected must be labelled properly. The GFCI needs to be marked "No Equipment Ground" and EACH of the downstream outlets marked ""GFCI Protected" and "No Equipment Ground". Generally, the GFCI outlet comes with several stickers for this purpose.

Finally, I recommend that all outlets be oriented with the "ground" hole on top if installed vertically or with the neutral slot on top if mounted horizontally. Contrary to popular belief there is no requirement that these look like a "face". Using the suggested method means that if a metallic object (for example a fork) were to fall on a plug that migh have worked loose a fraction of an inch, it will contact the "ground" prong (if preset) in the case of a vertical outlet or the neutral prong if a horizontal outlet.
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Old 04-24-2012, 12:09 AM
Wannabe12 Wannabe12 is offline
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I just found this site while searching Google for electrical issues. I am in Wisconsin, I know very little about codes. 4-5 yrs. ago, I had the house "re-wired". The swiftness of the contractor was impressive, he really looked like he knew what he was doing. I didn't think it was necessary to check his work.

(The fuse box, which contained 8 circuits, was replaced with a 200 amp breaker box with 18 circuits.), as well as a 60 amp sub-panel in the garage.

There were some outlets in place already with a three prong recepticle,without the ground port connected to anything. It was the same after he left.

There was an exterior outlet that he said he re-wired that wasn't grounded after he left. I found out about that much later, after my wife got shocked by it.

I know how to read those little golfball sized testers which told me the outlet was reverse polarity and open ground. I fixed that one.

Yesterday I got shocked by the light switch in the bathroom, (no wet hands) which has a GFCI outlet right next to it. One outlet has 60 volts when the breaker is off. The one behind the refrigerator, I specifically told him to run a new circuit to because sometimes it works and sometimes it doesn't. It worked for quite awhile after he left but it went out again. I checked the voltage with the breaker closed, i.e. in service, and my meter said it had 97 volts.

I don't know if it's been too long to go after him or not. I'm on disability and the wiring was done with a government re-hab loan.

Any thoughts?
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  #15  
Old 04-24-2012, 05:44 PM
johnpost johnpost is online now
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Quote:
Originally Posted by Wannabe12 View Post
Any thoughts?
get an electrician, different from the one who did the wiring, out to look at your situation.

don't use receptacles or switches that have given you shocks.

don't try to fix things yourself, even if you don't die in the process you could create a hazard that would produce shock or fire later. it takes skill to sort out incorrect or poor previous work or deteriorating wiring.
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  #16  
Old 05-21-2013, 08:24 PM
Electrified Electrified is offline
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Thank you!

I am not sure how old the post is at this point... But THANK YOU so very much for correcting the misinformation, I was just randomly reading through some of the "web" and saw this, the information that was being given was.. mmmm partially true. At any rate thanks for clearing this up, I was going to do the same thing you did!!
--Ele


Quote:
Originally Posted by TransistorJunction View Post
This post is over ten years old but I'm posting an update for anyone reaching it via a web search. Some of the information provided previously is incorrect. A GFCI works by constantly sensing the current running though both the hot and neutral wires. If there is even the slightest difference between the two, the circuit is shut off immediately.

Therefore if any current is flowing from the hot wire to ground instead of back through the neutral wire the power will be instantly disconnected. That is why no ground wire is needed.

Also, it is usually NOT necessessary to replace EVERY ungrounded outlet with a CFGI outlet. Typically several outlets are on the same circuit. As long as the FIRST outlet in the chain that has its power coming directly from the circuit breaker is a GFCI, then the rest of the outlets on the circuit AFTER the GFCI outlet are also protected by it.

This is why is is critical that ALL of the following be identified correctly:
1) Hot vs. Neutral wires

2) Line vs. Load wires (The wire coming IN from the source or previous outlet in the chain is the LINE, and a wire going out to the next outlet is the LOAD)

3) The FIRST outlet in a circuit must be determined, as that must be the one replaced with the GFCI outlet. The others can be replaced with regular three prong outlets (with no connection to the ground screw).

So use the money saved by not needing to replace every outlet with a GFCI and invest in a good meter or voltage detector. Turn the circuit breaker off and verify that every outlet you plan on replacing is unpowered. If not, then it is on a different circuit. Work on only one circuit at a time. Find ALL outlets on that circuit then disconnect ALL wires from each one (be sure the power is still off). If all wires on all outlets are not disconnected then there is the possiblity of power feeding back through the neutral and you will get misleading results (and possibily a shock from the neutral wire).

Make sure no wires are touching each other or anything else, and that all exposed wires are proected from childern, pets, etc. then have someone turn the power back on and find the ONE hot wire. This will be the HOT LINE for the FIRST outlet. Turn the power off again and connecte this wore to the HOT, LINE terminal. The corresponding wire will be the NEUTRAL LINE connection for that outlet. If there is another pair of wires at that outlet that go to the next outlet, connect these to the LOAD terminals, again observing which is hot and neutral.

Now the rest of the outlets on that brach circuit can be replaced with regular three prong oulets. There is no distinction between line and load on these, but be sure the hot wires (usually black) go to the darker of the screws (usually brass colored) and the neutral wires go to the lighter screws (usually silver coloered). If you look closely at an outlet you will see that one of the vertical slots is longer than the other. The hot is the shorter of the two.

In addition, as noted earlier, ALL outlets affected must be labelled properly. The GFCI needs to be marked "No Equipment Ground" and EACH of the downstream outlets marked ""GFCI Protected" and "No Equipment Ground". Generally, the GFCI outlet comes with several stickers for this purpose.

Finally, I recommend that all outlets be oriented with the "ground" hole on top if installed vertically or with the neutral slot on top if mounted horizontally. Contrary to popular belief there is no requirement that these look like a "face". Using the suggested method means that if a metallic object (for example a fork) were to fall on a plug that migh have worked loose a fraction of an inch, it will contact the "ground" prong (if preset) in the case of a vertical outlet or the neutral prong if a horizontal outlet.
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  #17  
Old 06-16-2013, 02:25 PM
Charliegwte Charliegwte is offline
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Neutral as Equipment Ground

As I gathered the green wires I'd run to replacement 3 hole duplexes
and tightened the split-bolt to connect them to the white-wire bus
in the fuse box I wondered:

Why isn't it appropriate to connect the Equipment Ground screw of a
duplex to the Neutral [white] wire when a separate ground is not
available as is the case in our 1950 vintage house ?

Would it defeat the GFCI detection ?
If so, would it be appropriate on a non-GFCI protected duplex ?
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  #18  
Old 06-17-2013, 07:59 AM
Dinsdale Dinsdale is offline
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How timely that someone resurrected this zombie. My wife and I are closing on a 1959 house next month, and I don't think I saw a single 3-prong outlet throughout the house!
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  #19  
Old 06-18-2013, 12:20 PM
Sparky812 Sparky812 is offline
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Quote:
Originally Posted by Charliegwte View Post
As I gathered the green wires I'd run to replacement 3 hole duplexes
and tightened the split-bolt to connect them to the white-wire bus
in the fuse box I wondered:

Why isn't it appropriate to connect the Equipment Ground screw of a
duplex to the Neutral [white] wire when a separate ground is not
available as is the case in our 1950 vintage house ?

Would it defeat the GFCI detection ?
If so, would it be appropriate on a non-GFCI protected duplex ?
OMG where to start!?
First, if you do not know why, then you should not be in your fuse box at all. In fact, technically only a licensed electrician should remove the cover from your box.

That said, it is extremely dangerous to connect any ground wire to a the Neutral (white) wire at a receptacle or anywhere else. Simply, it would energize the ground as well as defeat any other safety that would be provided by having aground.

The neutral bus in your box is grounded so that in case of a short at the panel, it is grounded.

And yes, the GFCI will not work.

Hopefully, this message reaches you alive and well.

Last edited by Sparky812; 06-18-2013 at 12:24 PM..
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  #20  
Old 06-18-2013, 05:05 PM
johnpost johnpost is online now
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in a fuse/breaker box is a deadly hazard there are many places to come in contact with electricity and die. only an experienced and knowledgeable person (beyond a DIY person) should go in there. if you weren't an immediate hazard to yourself you could create a hazard for anyone in the house later.

the grounding connection of anything does not carry any current except when something wrong is happening. do not connect it to anything but something grounded.

if a house has vintage wiring it might be a good idea to get an estimate on upgrading the electrical. if the total house is not upgraded then some new circuits could be added where higher current or grounding is needed.
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  #21  
Old 06-19-2013, 09:11 AM
Dinsdale Dinsdale is offline
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Good news - looking closely, all the wiring I could see in the sub-basement is in conduit, the panel appears to be grounded, and there are several 3-prong outlets in the level of the house where a family room addition was built. So hopefully things will not be as archaic as I had feared. We'll get an electrician in to replace the panel, upgrade to 200 amp, give the system a quick once-over and get to town replacing outlets! (Is this the "shocked" smilie?)
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Old 11-20-2013, 10:06 PM
tramdr tramdr is offline
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uses cold water pipe for ground

I bought the family house I grew up in after my parents retired to Fl. They have had it rewired with Circuit breakers as opposed to the old fuse box. It was also moved. I noticed that the outlets are still 2 wire and the Ground for the breaker box is a very heavy maybe 4x O gauge or heavier going across about a room and a half and tied to the main water pipe entry. This doesn't seem right to me. Any thoughts?
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  #23  
Old 04-20-2014, 04:55 PM
southerngs southerngs is offline
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What about 220?

Quote:
Originally Posted by Sparky812 View Post
OMG where to start!?
First, if you do not know why, then you should not be in your fuse box at all. In fact, technically only a licensed electrician should remove the cover from your box.

That said, it is extremely dangerous to connect any ground wire to a the Neutral (white) wire at a receptacle or anywhere else. Simply, it would energize the ground as well as defeat any other safety that would be provided by having aground.

The neutral bus in your box is grounded so that in case of a short at the panel, it is grounded.

And yes, the GFCI will not work.

Hopefully, this message reaches you alive and well.
To Sparky and everyone else who believes that mixing ground and neutral wires is a fate similar to death: How do you explain the code-approved use of the ground wire for neutral on 220-volt appliances? Until recent years, all stoves, ranges, etc. were wired this way. Any 110-volt portion of the stove (such as the oven light and the clock) used the ground wire for neutral. And if you buy a new stove to plug into an old (3-wire) 220-volt outlet, you are instructed to connect the neutral to ground. Yes, newly wired houses use 4 wires for 220 volt appliances such as a range, but it's still acceptable under code to use ground wire for neutral when connecting new appliances to older 3-wire 220 plugs. Wouldn't this, in your words, "energize the ground"?

Sparky also writes "The neutral bus in your box is grounded so that in case of a short at the panel, it is grounded." In fact, at least in some boxes, the neutral bus and the ground bus are the SAME bus. Ultimately, all neutral goes to ground. Responses welcomed.
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  #24  
Old 04-20-2014, 09:11 PM
engineer_comp_geek engineer_comp_geek is offline
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Quote:
Originally Posted by southerngs View Post
Yes, newly wired houses use 4 wires for 220 volt appliances such as a range, but it's still acceptable under code to use ground wire for neutral when connecting new appliances to older 3-wire 220 plugs. Wouldn't this, in your words, "energize the ground"?
If everything is wired correctly and perfectly functioning, there's no real hazard. But what happens if something breaks?

Start looking at all of the different failure scenarios. If a hot wire breaks, the thing just stops working. No biggie. But if your appliance uses the neutral as its safety ground, then the case of the appliance is directly connected to neutral. Now, what happens if the neutral gets corroded and breaks? Maybe there was water dripping on the socket since these things are usually in a basement, for example. Your dryer is off, but it probably has some control circuits that are powered by 120 volts, and are therefore connected from one hot to neutral. Only your neutral is busted, so the voltage goes through the control circuitry and energizes the case, and now the case floats up to 120 volts. The current is going to be limited by the impedance of the control circuitry, but it's still a shock hazard. If you touch the case of the dryer and earth ground (a metal support pole nearby, a piece of plumbing, a sink, etc) then you get shocked.

If, however, your device uses a separate safety ground, if the neutral connection breaks, then the neutral floats up to 120 volts, but nobody really cares because it's inside the dryer and there's no chance of you touching it. The dryer case is on a separate ground, and remains grounded.

If you go through all of the different failure scenarios, what you find is that it's fairly easy to end up with a hot case in the older system that uses the neutral as the safety ground, but you require multiple failures to end up with a hot case with the separate safety ground, which is much less likely to occur.

The separate safety ground is clearly much better.

Is the old way "a fate similar to death"? Well, that's a bit of an exaggeration. As long as nothing breaks, it's perfectly safe. But if something breaks, it is more likely to result in a shock hazard, and can potentially kill you.

As for why it is still to code, that's the way the U.S. electrical code works. If you have older stuff, you don't have to replace it all every time the code changes. Otherwise most homes throughout the U.S. would require significant rewiring.
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  #25  
Old 04-21-2014, 12:21 PM
engineer_comp_geek engineer_comp_geek is offline
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Quote:
Originally Posted by tramdr View Post
I bought the family house I grew up in after my parents retired to Fl. They have had it rewired with Circuit breakers as opposed to the old fuse box. It was also moved. I noticed that the outlets are still 2 wire and the Ground for the breaker box is a very heavy maybe 4x O gauge or heavier going across about a room and a half and tied to the main water pipe entry. This doesn't seem right to me. Any thoughts?
This is an old thread, but just for completeness, here's the answer to this part.

Grounding standards have changed significantly over the years. At some point they required the cold water pipe to be used as an electrical ground, because it made a good ground and pretty much every house had one. Then plastic pipe came along and all of a sudden that reliable metal pipe wasn't always metal any more, so they changed the standard. In modern homes a separate ground rod has to be used to ground the electrical system. However, you still need all of the water pipes in the house grounded because if you don't ground them and a hot wire ends up shorting to a water pipe somewhere, then your entire water system becomes a huge shock hazard. So the cold water pipe is still grounded, but it is no longer the primary electrical ground for the house.

There's no requirement to go back and rewire a house every time the code changes. However, if you change something, the parts that you change all have to be brought up to current code. So when the electrical box was changed out, that all had to be brought up to current code. That means installing a new ground rod and grounding the water pipes at the water service entrance, which is why they had to install a great big long run of thick copper ground wire.

Admittedly it's a bit silly to have the breaker box brought up to a modern grounding system when all of the outlets are still 2 wire without a safety ground, but the outlets weren't touched so there's no requirement to change them to modern 3 pronged outlets with modern 2 conductor plus ground wiring. If you wanted to bring the entire house up to modern code, all of the wiring and the outlets would have to be changed, GFCIs would have to be installed in certain locations (bathroom and garage, typically), and AFCIs would have to be installed on bedroom circuits.
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Old 08-08-2014, 12:40 AM
Futbol9 Futbol9 is offline
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Hello everybody.Bought a 4.9 cubic feet freezer but where I wanna put it, the outlet is a two prong one and has no ground. There are 2 black and two white wires coming out to the outlet no ground wire. Anyway, I was told I could replace it with a GFCI outlet to plug in my freezer or also to run the ground cable from a close grounded outlet to the ungrounded one. Do to want to run wires from main pannel to this outlet. Would rather do one of the first two options mentioned above. Thank u.
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Old 08-08-2014, 05:21 PM
Futbol9 Futbol9 is offline
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So can i ground a two prong ungrounded outlet from a grounded outlet or should I just replace it with a GFCI outlet to plug in my freezer?
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Old 08-09-2014, 12:31 AM
johnpost johnpost is online now
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putting a freezer on a GFCI circuit might trip the GFCI at some random motor start and leave you with a nonrunning freezer. if the receptacle is just running the freezer then it doesn't need to be GFCI protected. if other receptacles are used for plugging small things into down strean then the GFCI receptacle can be downstream.

if you can run a grounding wire from another location then run a 3 wire cable with all the wires to that location.
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