replacing old non-grounded (2 prong) electric receptacles

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I have a 50 year old house that I am remodeling. It has the old 2-prong style (non-grounded) receptacles. From what I understand, the code will not technically allow it, but, is there any reason why I shouldn't use the regular grounded receptacles to replace the old two prong? The old ones have been painted over several times and I'm thinking it will look nice to replace them. An electrician tells me that the neutral wire can be daisy chained to the ground screw so that we don't need to run a new ground wire. Is there any harm or problem or reason why I would not want to do that? You can buy the old 2-prong style, but they are expensive. I was told that you can also put a GFI at every position, but that is even more expensive.
Thank you very much for your thoughts on this matter.
David
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I'd stay as far away from that electrician as I could.

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On 5 Aug 2003 19:46:14 -0700, snipped-for-privacy@htn.net (David Jensen) wrote:

Becuase the nueutral could break somewhere, putting the full line voltage on it, and the bootlegged ground.

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Don't do it!! It is dangerous, big time.
If you want better looking outlets, just buy new non-grounded ones. I believe you can still get them, but not at Kmart.
--
Joseph E. Meehan

26 + 6 = 1 It's Irish Math
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If you have a metal box and BX (metal sheathed) cable all the way back to your main breaker box, it is possible that your system is grounded. In that case you can put in grounded outlets.
But as everyone has pointed out, you cannot connect the ground to your neutral and think that it is grounded. Nor will a GFCI replace a real ground.
So I would recommend getting a licensed electrician out there. S/He can tell you what the actual situation is.
--
Peace,
BobJ

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On Tue, 05 Aug 2003 22:49:27 GMT, "Joseph Meehan"

Our local Wal-Mart actually does carry them, I was surprised to find them there.
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Can you please elaborate and help me understand why it is dangerous? I'm not questioning you, I just want to understand.
Thanks.
David

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A neutral carries current, a ground does not. Many grounded devices attach the outside of the case to the ground. Touch the devices case and a good ground means you are in the grounding path and if there happens to be a fault or a little resistance in the neutral circuit, you become part of the circuit. Not good.
--
Joseph E. Meehan

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It's odd that we've mandated 3-hole receptacles, but not 3-plug appliances.
Your refrigerator, washer, and perhaps the microwave may be the only "grounded" appliances in your house.
When we get to GFI circuit-breakers in the distribution panels, we can go back to two-hole outlets. ( it's just a matter of time )
On Wed, 06 Aug 2003 09:52:02 GMT, "Joseph Meehan"

<rj>
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Because the three contact outlets are backward compatible. Also due to dual insulation construction many appliances don't need a ground for safety, but some do.
--
Joseph E. Meehan

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wrote:

My computer uses/has a ground prong. Some of our kitchen appliances have ground prongs.
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The thing that still confuses me with the statement, "A neutral carries current, a ground does not" is that both the neutral and the ground tie into the same grounding block inside the panel. To this laymen's mind it seems that they would be carrying the same current since they are tied together at the panel. In other words, if they tie together at the panel, what's the difference in tying them together at the receptacal? What am I not understanding here?
Thanks for taking the time to respond.
David

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On 21 Aug 2003, David Jensen wrote:

Yes, they are tied together at the service panel, and the two of them along with the black(red) wire go out to your circuit. It might be easier to understand if you don't just think of one light fixture or duplex, but rather a "typical" home circuit of 3 or 4 "convenience outlets" on one breaker. And it might help to envision the wires "spread out" just a little more, rather than bundled in a vinyl or steel jacket. Picture your Black & White with all of your devices wired across them, and your bare ground wire hanging out ther in the distance. -Always- there, but -never- intentionally connected to the Neutral side of a device. If you think of only 1 device, say a duplex receptacle, it's very easy to think "so what if they're wired together, it's the same wire", but if you look at that 3 or 4 duplex run, and consider any of the points in the middle, you should realize that it's -not- the same wire. IOW, you could open up any of those boxes in that branch circuit and expect: a) the white wire IS carrying current, and b) the neutral wire is NOT carrying current.
As soon as somebody screws with that, they wipe out that intended safety buffer. IOW, if you go to the 2nd outlet in that chain and connect the white and neutral, the next guy who comes in contact with the white/neutral back @ outlet #1 is in for a surprise, the severity of which depends on how much resistance is in that ground path as compared to true ground. If it's a good solid connection they may not een feel a tingle, if it's worse, they could get a substantial shock.
The key to it all (remembering the thing about "A neutral carries current, a ground does not") is that anyone working on the circuits should be able to assume that there is never any current flow through ANYTHING that is supposed to be at ground potential, and that includes metal boxes and cover plates along with conduit, BX, and the bare wire inside a run of Romex.

Hey, it's a slow night, ya know? <g>
--
TP

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Your options are use GFIs, tie grounds to neutrals, or add a ground wire and use three prong outlets.
As others have posted, you can put in a three prong outlet and wire the ground (bare copper) to the neutral (white wire). This is not a good idea as you will defeat the ground as a safety device and could be creating a shock hazard. If the neutral fails between the outlet and the service panel the grounded case will be HOT (ie 120 volts). An inductive load such as a motor will not have much resistance. Kill this idea, not yourself (and whoever owns your house next).
The easiest legal thing to do is to use a GFI outlet. The GFI comes with a bunch of stickers including one that says "No Equipment Ground" that needs to be put on the outlet. If money is a consideration then you only need one GFI for the first outlet in each circuit. Connect the downstream outlets to the LINE terminals and they will be protected too. Note that GFIs are not recommended for larger motors such as stationary woodworking saws and washing machines or for devices that should not loose power such as medical equipment or refridgerators. Determining which outlets are downstream and which is the first outlet may require disconnecting the hot wire (black wire) (pull the fuse or breaker first) to find out which outlets go dead. Just to make things difficult there is type of circuit called a shared common that has two hot wires (probably black and red) and they share a single neutral (white). If the voltage between the black and red wire is over 200 volts then you can only use a GFI for each outlet, a single GFI cannot protect the downstream outlets without totaly rewiring the circuit.
If you really want to stay cheap or want to do it right then run new ground wires. Run one ground wire for each circuit and try to follow the routing of the circuit. The new wires can be run under walls if a basement or crawl space provides access. You can also run the wire under the baseboards with the runs to the outlet inside the wall or in a grove in the drywall. Home electrical wiring books explain how to run wires in existing structures, its more than I can explain in a usenet posting. This is also one of the topics that dont' think I could explain without non-family oriented language. If your service panel does not have a ground connection then tie the new ground wires to a cold water pipe or put in a new ground spike (or preferable both).
PS Do not try any of this if you do not have a basic understanding of how a house is wired.
PPS To really do this right pull the drywall off. You should see my kitchen (to be).
PPPS Please correct if I did not get the grounding correct.
Richard Kaiser
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wrote:

As was discussed, tieing grounds to neutrals is not an option.
Another option is to re-wire with modern wiring that has a ground conductor.
GFCIs are only an option where only personal safety is a concern. If there are other reaons for havong a grounded outlet, such as surge protectors and EMI/RFI sheilding of electronics gear, you absoultely need to have a ground back to the panel.

No, others have stated you cannot, for the reaons you state though.

If you really want to get this right, simply replace the old 2-wire wiring with new 2 wire + ground.

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snip: "GFCIs are only an option where only personal safety is a concern. If there are other reaons for havong a grounded outlet, such as surge protectors and EMI/RFI sheilding of electronics gear, you absoultely need to have a ground back to the panel."
So am I reading this correctly when I interpret that a surge protector will do no good without a true ground? Also could you elaborate by what you mean by "RFI sheilding of electronics gear" and where that comes into play? Thanks again.
I've very much appreciated all the response I've recieved on this thread.
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On 24 Aug 2003 02:46:36 -0700, snipped-for-privacy@htn.net (David Jensen) wrote:

Those need a real ground to drain surges and EMI/RFI radiation to ground.

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There are many different grounds. For example that outlet ground is for human safety. It will also assist in common mode noise reduction. It is different, but remotely connected to earth ground - a different ground. Also interconnected would be the single point ground between entertainment system components to eliminate audio noise. That ground is different from outlet safety ground even if the two grounds share common wires.
Computer has a motherboard ground that must be distinct and separate from (but have a single point connection to) computer chassis ground. Chassis ground must be connected to outlet safety ground for human safety reasons and for static electric shock reasons. Again same ground performing multiple functions.
But is earth ground necessary to remove static electricity? No. The ground for static electricity is typically bottom of shoes. That outlet safety ground would complete a circuit - connect (short circuit) a static electric shock from human hand, through chassis and outlet safety ground, through other materials normally considered non-conductive, to ground underneath shoes. Same wires connecting to different grounds.
Point is that many grounds are defined. They can be different. They may be interconnected. They will perform different functions such as human safety, noise and transient reduction, static electric discharge, etc. They may share common wires and other conductive materials. To identify what a ground does, one must first identify why grounding is necessary and all electronic components in that circuit.
Example - we earth ground a radio antenna input directly at the radio - well less than 1 foot of wire. Radio reception is severely diminished. We then ground same antenna input with 100 foot wire connected to same ground. Suddenly radio gets excellent reception. Why? If wire is the perfect conductor as so many wish, then that 100 foot wire to ground should have also eliminated radio reception. Therein lies the reason why so many grounds are different. They are all separated by electronic components - ie. wire.
David Jensen wrote:

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Bad example, and incorrect.
The 100' wire to ground would actually be used as one part of a dipole antenna, therefore increasing the antennas signal capturing ability. The 1' ground (because of it's short length and difference in length to the other side of the antenna lead) would basically shut down the antennas' ability to capture a signal.
Mike
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Radio on 100 foot wire was a good example. But you misunderstood what the example demonstrates. An earthed 100 foot wire does not short out radio reception AND acts as a dipole antenna BECAUSE wire is not a perfect conductor. Wire has impedance. Impedance is why signals on that 100 foot wire are not shorted out - end to end. And that was the point. Wire is electrically different at both ends. If wire was a perfect conductor, then wire could not act as an antenna.
Radio signal captured at near 50 foot is not shorted out by far 50 foot of wire because, and again, wire is not a perfect conductor. Wire is electrically different at both ends.
Some here would rather insult than first learn these basic facts. They should have first asked for clarification so that they could learn. They 'assume' that 10 AWG power wire is electrically equal at each end - which is enough justification to insult? If true, then joining neutral and ground together in a wall receptacle would be perfectly acceptable. Then we need only run one wire back to breaker box - not a separate white and green wire. We intentionally run two wires from same point inside breaker box to receptacle because wire is not a perfect conductor.
Even though both white and green are connected together in breaker box, they are electrically different at their other ends. Why? Because all wire has electronic characteristics as the 100 foot radio wire demonstrates; as a single point ground to stop hum between audio components demonstrates; as separated chassis and motherboard grounds makes a computer resistant to static electric problems.
Wire has tiny resistance and impedance. Wall receptacle end of a white wire is not electrically same as other end in breaker box. And all grounds, even though interconnected, are quite different as explained in that earlier post.
Outlet receptacle ground is a human safety ground. From the perspective of radio waves that we call surges, that outlet safety ground is all but disconnected from earth ground. IOW outlet safety ground is not earth ground. Breaker box ground may or may not be earth ground depending on electrical characteristics of the earth ground wire - ie length, number of sharp bends, etc.
Wire is always considered electrically different at both ends. Even when wiring a house that meets NEC requirements; code is written knowing that wire is not electrically same at both ends. Those who insult should first learn these basic electrical principles; why grounds in different locations serve different tasks; and how wire works.
Mike wrote:

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