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  #1   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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
  #2   Report Post  
HeatMan
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

I'd stay as far away from that electrician as I could.

"David Jensen" wrote in message
om...
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



  #3   Report Post  
Joseph Meehan
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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


"David Jensen" wrote in message
om...
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



  #4   Report Post  
Marilyn and Bob
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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

"Joseph Meehan" wrote in message
...
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


"David Jensen" wrote in message
om...
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




  #5   Report Post  
Gary Tait
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On 5 Aug 2003 04:27:24 -0700, (David Jensen) wrote:

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


Don't make a bootleg ground. All you need to do is wire a GFCI to the
first outlet of the circuit, if it is linear wired (outlet box to
outlet box). If it is octupus wired (the outlet box wires lead to an
ar joined in the ceiling), you should rewire the circuit feed into an
outlet box (with the GFCI outlet in there), with a new wire to the
fusebox, if you don't have a breaker panel you can replace the normal
breakers with GFCI one. GFCIs only provide personal safety, they don't
provide an earth ground that some electronics need.



  #6   Report Post  
J Kelly
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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

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.


Our local Wal-Mart actually does carry them, I was surprised to find
them there.
  #7   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

Can you please elaborate and help me understand why it is dangerous?
I'm not questioning you, I just want to understand.

Thanks.

David

"Joseph Meehan" wrote in message ...
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


"David Jensen" wrote in message
om...
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

  #8   Report Post  
Joseph Meehan
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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

26 + 6 = 1 It's Irish Math


"David Jensen" wrote in message
om...
Can you please elaborate and help me understand why it is dangerous?
I'm not questioning you, I just want to understand.

Thanks.

David

"Joseph Meehan" wrote in message

...
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


"David Jensen" wrote in message
om...
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



  #10   Report Post  
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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"
wrote:

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.


rj


  #11   Report Post  
Joseph Meehan
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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

26 + 6 = 1 It's Irish Math


"RJ" wrote in message
...
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"
wrote:

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.


rj



  #12   Report Post  
Gary Tait
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On Wed, 06 Aug 2003 21:34:04 -0400, "RJ"
wrote:

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 )


My computer uses/has a ground prong. Some of our kitchen appliances
have ground prongs.
  #13   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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


"Joseph Meehan" wrote in message ...
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

26 + 6 = 1 It's Irish Math


"David Jensen" wrote in message
om...
Can you please elaborate and help me understand why it is dangerous?
I'm not questioning you, I just want to understand.

Thanks.

David

"Joseph Meehan" wrote in message

...
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


"David Jensen" wrote in message
om...
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

  #14   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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


"Joseph Meehan" wrote in message ...
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

26 + 6 = 1 It's Irish Math


"David Jensen" wrote in message
om...
Can you please elaborate and help me understand why it is dangerous?
I'm not questioning you, I just want to understand.

Thanks.

David

"Joseph Meehan" wrote in message

...
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


"David Jensen" wrote in message
om...
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

  #15   Report Post  
I-zheet M'drurz
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On 21 Aug 2003, David Jensen wrote:

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?


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.

Thanks for taking the time to respond.


Hey, it's a slow night, ya know? g

--
TP


  #16   Report Post  
I-zheet M'drurz
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On 21 Aug 2003, David Jensen wrote:

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?


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.

Thanks for taking the time to respond.


Hey, it's a slow night, ya know? g

--
TP
  #17   Report Post  
Richard Kaiser
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

"David Jensen" wrote in message
om...
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


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
  #18   Report Post  
Richard Kaiser
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

"David Jensen" wrote in message
om...
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


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
  #19   Report Post  
Gary Tait
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On Fri, 22 Aug 2003 04:56:50 GMT, Richard Kaiser
wrote:

"David Jensen" wrote in message
om...
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


Your options are use GFIs, tie grounds to neutrals, or add a ground wire
and use three prong outlets.


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.


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


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

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).

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


PPPS Please correct if I did not get the grounding correct.


Richard Kaiser


  #20   Report Post  
Gary Tait
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On Fri, 22 Aug 2003 04:56:50 GMT, Richard Kaiser
wrote:

"David Jensen" wrote in message
om...
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


Your options are use GFIs, tie grounds to neutrals, or add a ground wire
and use three prong outlets.


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.


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


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

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).

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


PPPS Please correct if I did not get the grounding correct.


Richard Kaiser




  #21   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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.
  #22   Report Post  
David Jensen
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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.
  #24   Report Post  
w_tom
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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:
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.

  #25   Report Post  
I-zheet M'drurz
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

On 24 Aug 2003, w_tom wrote:

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.


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.


You are full of ****.

Ground is Ground is Ground is Ground.

There is *always* a resistance component between what we are
taking to be *ground* and true, absolute earth ground. Is
there a half ohm difference between that 10' ground rod you
just sledged into the soil under your basement and the core
of the earth? You bet your ass there is. But BOTH are at
practical ground potential. Quit trying to make a friggin'
mountain out of a molehill.

The middle/round hole on a duplex outlet when connected to
a continuous copper wire running to the ground/neutral bus
bar in your service panel is *GROUND*, just as is the
grounded chassis of something having a 3 prong line cord
plugged into that duplex outlet.

Go split hairs somewhere else and quit bull****ting these
people.

--
TP


  #26   Report Post  
Oscar_lives
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles


"I-zheet M'drurz" wrote in message
...
On 24 Aug 2003, w_tom wrote:

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.


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.


You are full of ****.

Ground is Ground is Ground is Ground.

There is *always* a resistance component between what we are
taking to be *ground* and true, absolute earth ground. Is
there a half ohm difference between that 10' ground rod you
just sledged into the soil under your basement and the core
of the earth? You bet your ass there is. But BOTH are at
practical ground potential. Quit trying to make a friggin'
mountain out of a molehill.

The middle/round hole on a duplex outlet when connected to
a continuous copper wire running to the ground/neutral bus
bar in your service panel is *GROUND*, just as is the
grounded chassis of something having a 3 prong line cord
plugged into that duplex outlet.

Go split hairs somewhere else and quit bull****ting these
people.

--
TP



You tell him, Tommy!!!



  #27   Report Post  
Mike
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

w_tom wrote in :

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.


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
  #28   Report Post  
w_tom
 
Posts: n/a
Default replacing old non-grounded (2 prong) electric receptacles

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:
w_tom wrote in :
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.


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.

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