Grounding - general questions

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  #1  
Old 02-23-03, 10:38 AM
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Grounding - general questions

Subject has probably been beat to death but I'll ask it anyway.

When you have older wiring - NM type cable running from the breaker box with no ground to Older 2 prong receptacles. If you replace these with 3 prong receptacles why is this worse than the 2 prong receptacles? In either case your not grounded. What is the real risk of this setup over just leaving the 2 prong receptacle as is?

Secondly when dealing with armored/bx cable - If there is no ground are you not grounded by the armored casing itself?
 
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  #2  
Old 02-23-03, 10:51 AM
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The problem is that appliances with three-prong plugs rely on that grounding connection for minimum safety. Without either grounding or GFCI, the appliance does not meet the minimum safety standards to which it was designed. Appliances with two-prong plugs rely on other safety devices, such as double insulated cases.

There has been a lot of discussion in this forum about grounding with BX cable. The issue is very confusing because the BX being manufactured today is different than the BX that was manufactured years ago. So it depends on which BX you're talking about.
 
  #3  
Old 02-23-03, 11:42 AM
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John

I know what you mean about different BX cables. In my house I've noticed older BX cable with no seperate ground wire as oppossed to new BX cable which has a small bare wire in addition to the white & black wires. If you have a situation where a fixture/receptacle or junction box is fed by this older style BX cable & you wish to tap into it using "newer" style BX with the ground wire where do you attach it? I would assume that attaching it to the junction/ receptacle box would be OK. Is this correct? & would it be considered grounded?

I must admit I feel somewhat DENSE in relation to this grounding issue. Despite having done a fair amount of wiring - including running new cable from the breaker panel, installing grounding bars, etc. And a general understanding of the need to be grounded (no pun intended). I still fine the issue - especially when referring to the way old systems versus new systems were grounded, & converting 2 prong to 3 prong outlets somewhat confusing.

Any good resources - I'm not talking about just reciting code - about the actual theory/basis behind the whole grounding issue preferably in laymen like terms.
 
  #4  
Old 02-23-03, 05:17 PM
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For replacement of non-grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C). C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The equipment grounding conductor of a grounding-type receptacle or a branch-circuit extension shall be permitted to be connected to any of the following: (1) Any accessible point on the grounding electrode system as described in 250.50 (2) Any accessible point on the grounding electrode conductor (3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates (4) For grounded systems, the grounded service conductor within the service equipment enclosure (5) For ungrounded systems, the grounding terminal bar within the service equipment enclosure If you use the water pipe, the connection must be within 5 feet of where the pipe enters the building.
You are permitted to replace a two-wire nongrounding type receptacle with a GFCI under the following in section 406.3 (3) Nongrounding-Type Receptacles. Where grounding means does not exist in the receptacle enclosure, the installation shall comply with (a), (b), or (c). (a) A nongrounding-type receptacle(s) shall be permitted to be replaced with another nongrounding-type receptacle(s). (b) A nongrounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interrupter-type of receptacle(s). These receptacles shall be marked "No Equipment Ground." An equipment grounding conductor shall not be connected from the ground-fault circuit-interrupter-type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle. (c) A nongrounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter. Grounding-type receptacles supplied through the ground-fault circuit interrupter shall be marked "GFCI Protected" and "No Equipment Ground." An equipment grounding conductor shall not be connected between the grounding-type receptacles. When you make this change be very, very careful that you get the hot "black" wire on the right side of the outlet.


(B) With Circuit Conductors. By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors.
NEC HANDBOOK COMMENTARY;
One of the functions of an equipment grounding conductor is to provide a low-impedance ground-fault path between a ground fault and the electrical source. This path allows the overcurrent protective device to actuate, interrupting the current. To keep the impedance at a minimum, it is necessary to run the equipment grounding conductor within the same raceway or cable as the circuit conductor(s). This practice allows the magnetic field developed by the circuit conductor and the equipment grounding conductor to cancel, reducing their impedance.
Magnetic flux strength is inversely proportional to the square of the distance between the two conductors. By placing an equipment grounding conductor away from the conductor delivering the fault current, the magnetic flux cancellation decreases. This increases the impedance of the fault path and delays operation of the protective device.
 
  #5  
Old 02-23-03, 05:37 PM
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Sorry, I haven't done research on sites you can learn from, but I will take a stab at the "old" way and "new" way. Without a separate grounding conductor, the ground fault basically will be spread throughout you wiring..... ex. lightning strike... the additional voltage without a grounding conductor will spread throughout the wiring, causing spikes in basically everything, blowing out the tv, stereo, microwave, refridgerator,... etc....
With a well grounded systyem, the lighting strikes will have some effect on your appliances, but MOST of the additional voltage will be dissipated through the ground... less likely to destroy your appliances, and more importantly, less likely to kill anyone who happens to be taking a shower at the time. "BX" cable, is not even legal anymore, what you now have is MC (metallic clad) cable. Reason being, many people tried to use that flimsy aluminum cable wrapped around bx as a ground, but realistically that was not enough to attract the voltage..... electricity like water and air, will flow toward the path of least resistance..... that little aluminum or steel cable had plenty of resistance, whereas the new MC with full sized copper grounding wire, has less resistance, and therefore better opportunity for the excess voltage to travel to ground.
Therefore, the problem with replacing a 2-prong receptacle with a 3 prong receptacle, is that when most people see a 3-prong receptacle they assume there is a ground, and they plug in devices that could cause a major spike in the system (due to the fact that it is designed to carry a ground-fault) into ungrounded systems........ basically creating a mess, a fire hazard, a health hazard, and an electrician's worst nightmare. Well, maybe not the worst... but potentially dangerous.
 
  #6  
Old 02-23-03, 07:35 PM
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The equipment ground itself rarely has much to do with lightning strikes,, thats the ground rod or grounding electrodes job. The equipment ground is to protect personnel against shorts to the case of the equipment and to provide a low resistance path back to the source in order to cause the breaker to trip or the fuse to blow. You have always had the ground rod but the equip ground was added to protect people.
 
  #7  
Old 07-12-06, 04:13 PM
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What about "ground lifts?"

Hi all, great post--learned a lot. One thing I think we may have overlooked is 3 to 2 prong adapters or "ground lifts". Lester, you said in your last post that replacing 2 prong outlets with 3 would create problems. But wouldn't using a ground lift on a 3 prong appliance into a 2 prong outlet create the same problem? I have replaced ungrounded (they may be grounded at the box) 2 prong receptacles with 3 prong...would I still be able to use these outlets if I ran cable from ground screw on duplex to metal housing of receptacle?
 
  #8  
Old 07-12-06, 04:55 PM
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Physically a three to two prong adapter works because a three prong cord can be plugged into an adapter and then into a two prong receptacle. This allows electricity to flow without having to cut the ground prong off the plug end of the cord.

However, these only work electrically if the receptacle box is properly grounded and a ground path exists to the screw holding the receptacle cover to the receptacle, and of course if the lugs or wire on the adapter is properly connected behind the screw.

These adapters are meant for temporary use. Indeed, I only use them when I need an extension cord for a two prong device, like my drill and the closest receptacle happens to be two prong and ungrounded.

Now on to your question.

One allowed method for replacing an ungrounded two prong receptacle with a three prong receptacle is to provide a proper ground. This ground can come from several places, but it must be a proper ground. If the receptacle box is properly grounded, then a pigtail or grounding wire from the box to the receptacle is a proper ground.
 
  #9  
Old 07-12-06, 05:15 PM
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Any good resources - I'm not talking about just reciting code - about the actual theory/basis behind the whole grounding issue preferably in laymen like terms.




For replacement of non-grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C). C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The equipment grounding conductor of a grounding-type receptacle or a branch-circuit extension shall be permitted to be connected to any of the following: (1) Any accessible point on the grounding electrode system as described in 250.50 (2) Any accessible point on the grounding electrode conductor (3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates (4) For grounded systems, the grounded service conductor within the service equipment enclosure (5) For ungrounded systems, the grounding terminal bar within the service equipment enclosure If you use the water pipe, the connection must be within 5 feet of where the pipe enters the building.
You are permitted to replace a two-wire nongrounding type receptacle with a GFCI under the following in section 406.3 (3) Nongrounding-Type Receptacles. Where grounding means does not exist in the receptacle enclosure, the installation shall comply with (a), (b), or (c). (a) A nongrounding-type receptacle(s) shall be permitted to be replaced with another nongrounding-type receptacle(s). (b) A nongrounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interrupter-type of receptacle(s). These receptacles shall be marked "No Equipment Ground." An equipment grounding conductor shall not be connected from the ground-fault circuit-interrupter-type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle. (c) A nongrounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter. Grounding-type receptacles supplied through the ground-fault circuit interrupter shall be marked "GFCI Protected" and "No Equipment Ground." An equipment grounding conductor shall not be connected between the grounding-type receptacles. When you make this change be very, very careful that you get the hot "black" wire on the right side of the outlet.


(B) With Circuit Conductors. By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors.
NEC HANDBOOK COMMENTARY;
One of the functions of an equipment grounding conductor is to provide a low-impedance ground-fault path between a ground fault and the electrical source. This path allows the overcurrent protective device to actuate, interrupting the current. To keep the impedance at a minimum, it is necessary to run the equipment grounding conductor within the same raceway or cable as the circuit conductor(s). This practice allows the magnetic field developed by the circuit conductor and the equipment grounding conductor to cancel, reducing their impedance.
Magnetic flux strength is inversely proportional to the square of the distance between the two conductors. By placing an equipment grounding conductor away from the conductor delivering the fault current, the magnetic flux cancellation decreases. This increases the impedance of the fault path and delays operation of the protective device.

This doesn't quite meet "laymans" terms.

BX: if true armored (steel) cable the armor can be considerd the ground, similar to a steel raceway. The bond wire inside is just that, A bond to assure the cotinuity in the armor, Don't confuse this with a ground. The new stuff "MC" cable, don't rely on this for a bond or ground, The conductors in this are THH/wn.
and there is usualy a ground conductor in it.
Any of this is only going to be good if you have a metal box appriate connectors and a good mechanical connection to it.

As John stated above the new equipment requires a ground for reference to operate properly.
The neutral picks up and returns the energy not used by the device/appliance etc. The ground will then take what is not returned and disapate it (voltage) thus balancing the entire system. The GFCI will take the voltage normaly absorbed by the ground and correct and protect you.
If you have a 2 wire system, use a GFCI receptical and feed thru, then if you use a 2 wire adapter, your still protected.
Others are more analitical than I, but this is the short and sweet of it. (Obviousley I'm not a technical writer), and also very open to a better way to explain it (simpley).
 

Last edited by lectriclee; 03-27-07 at 07:34 PM. Reason: This was not me! I can't type that fast or that long. Thanks for the credit but.... Moderators may be confused.
  #10  
Old 07-12-06, 09:42 PM
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re:re what about ground lifts?

Racraft,
Thanks much for the timely response, made a lot of sense. I found an article on how to test your outlet to see if it is properly grounded: http://www.popularmechanics.com/home...c/1889457.html
...didn't have the light tester but used my continuity test on my multimeter which I think should be the same thing. Ran the leads from ground screw on plate to hot/live on each plug of duplex and sure enough...nada, no ground.

The wiring in my house is definetly aged. Have some sensitive equipment, just trying to find the safest setup without having to run ground wire back to service panel ground bus--think that is a little out of my realm.

There are four copper, cloth-coated wires (2 white neutral/2 black hot) in each metal outlet box--2 boxes total. Wires look to be run through conduit (maybe plastic?) No other wires to speak of. Both these boxes are on the same 20A breaker at the service panel. Currently have 3 prong grounded duplex in each,
which apparently are grounded to nothing.

Equipment: most notably window AC unit (850W/7.3A) with LCDI 3 prong plug. I have a printer, modem, router, etc. that are all on a surge protected power strip. Laptop is on a single outlet surge protect (1700 joules). I am most worried about the AC reaking havoc on all equipment since everything is on the same circuit.

Here's my question(s),--sorry bout long post--: Is my current setup (ungrounded 3 prong) unsafe? Are the surge protectors on laptop and strip, and LCDI on AC enough protection? Should I replace receptacles back to 2 prong, or with GFCI and if so won't GFCI be ungrounded as well? Just looking for the safest setup without running ground through walls back to panel.

Thank you very much in advance
 
  #11  
Old 07-13-06, 04:28 AM
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Your setup is unsafe when you attempt to plug in something that needs a ground. For the window AC it is unsafe. If you plug in a typical table or floor lamp it is not unsafe.

However, it is a code violation so you you should fix it.

Your surge suppressors are useless. You may as well remove them. They won't work without a ground (unless they are high end expensive models).

If you have conduit, adding a ground is feasible. If you do not have conduit then adding a ground is a bit more challenging.

To fix your problem you must either

1) Provide a proper ground. This can be done by rewiring or adding a ground wire.

2) Providing GFCI protection and then labeling the receptacle as "No Equipment Ground." GFCI protection can be at each receptacle, can be at an upstream receptacle, or can be at the circuit breaker.

Note that providing GFCI protection allow you to use three prong receptacle (properly labeled, as indicated above), but does NOT provide a ground. Your surge suppressors won't work, and other electronics that might need a ground may not work properly.
 
  #12  
Old 07-14-06, 12:00 PM
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I see what you're saying about the surge protectors.
I will definetly comply with code and switch.
The problem is which option to choose.
Gfci seems like a temporary fix, and from what I gather, not the same thing as good surge protection. I would like to run a ground but I am renting and without a major disaster first, don't think my renter will go for the cost.
Isn't there a way to ground from the neutral at the service box and thereby have my whole house grounded?
What about whole house surge protection, provided I run a ground to earth? Would this eliminate the need for groundwire to every outlet?
Is it a good idea to run a ground just to one room?
You said AC was unsafe--what exactly does the LCDI plug protect then?
Also, on my laptop power supply--I can use either 2 prong or three--guess I should be using 2 prong then, without having a ground.
For future reference--what kind of cable to I have in my outlets? The actual cable is solid copper--not braided--and wrapped in black cloth like material. Is this K&T?
I really appreciate you taking the time to help.
 
  #13  
Old 07-14-06, 12:09 PM
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Originally Posted by wolfy357
Gfci seems like a temporary fix, and from what I gather, not the same thing as good surge protection.
A GFCI does not provide a ground and has no effect on surge protection.


Originally Posted by wolfy357
Isn't there a way to ground from the neutral at the service box and thereby have my whole house grounded?
No. The earth ground which should already be present at the panel is not the same thing as the safety ground to each receptacle.


Originally Posted by wolfy357
What about whole house surge protection, provided I run a ground to earth? Would this eliminate the need for groundwire to every outlet?
A surge protector and a ground are different items. A surge protector does not provide protection against a problem at an appliance.


Originally Posted by wolfy357
Is it a good idea to run a ground just to one room?
If you need a ground in one room then running a ground to that room is fine.


Originally Posted by wolfy357
You said AC was unsafe--what exactly does the LCDI plug protect then?
I don't know what LCDI means. A GFCI receptacle provides protection if you plug something in to it.

Originally Posted by wolfy357
Also, on my laptop power supply--I can use either 2 prong or three--guess I should be using 2 prong then, without having a ground.
Yes, use the two prong one. However, it probably makes no difference electrically.


Originally Posted by wolfy357
For future reference--what kind of cable to I have in my outlets? The actual cable is solid copper--not braided--and wrapped in black cloth like material. Is this K&T?
This sounds like old NM cable.
 
  #14  
Old 07-14-06, 03:18 PM
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OK ... I am new here, have read this entire thread, and still am a bit confused (perhaps that is because I just qualified for Medicare ). So I will ask what seems to have been asked before, but I am not sure I sussed the answer correctly from what I have seen.

I have just bought an old - circa 1912 - house. Much of the electrical system has been updated, but not all of it. There is still some old, two wire BX to a few receptacles. So my questions are:

1. If the BX is well secured to the metal wall box for the two prong duplex receptacle, and I replace the two prong with a three prong, will including a ground wire from the green ground screw on the new receptacle to the box be effective?

2. Will it be safe?

3. If I do the above, and plug a circuit tester into the new receptacle, and it says OK (two yellows and no red), does that mean that I am OK?

Thanks. And sorry for the repeat.
 

Last edited by gfmason; 07-14-06 at 04:48 PM.
  #15  
Old 08-09-06, 11:52 PM
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To answer your questions:
(and I'm sure Racraft will correct me if I'm wrong here)

1. Will including a ground wire from the green ground screw on the new receptacle to the box be effective?

No, In order to have a properly grounded outlet, the ground wire needs to run back to the service panel ground terminal, which in turn runs to actual ground (usually connected to a metal stake like rebar and drove into ground), or could possibly be grounded to water pipe somewhere, that is if your system is grounded at all.
The setup you describe would result in a "hanging ground" and would not redirect any kind of surge to actual ground.

2.Will it be safe?

It would be just as safe as your original two prong outlet, obviously a grounded duplex provides less of a risk of any appliances or equipment being damaged in the event of a surge (i.e. lightning storm, etc), than a non-grounded one.

3. If I do the above, and plug a circuit tester into the new receptacle, and it says OK (two yellows and no red), does that mean that I am OK?

Not sure, you would have to refer to your tester's manual to answer that question. Here is a simple test you can perform to check ifyour outlet is grounded:

http://www.popularmechanics.com/home...c/1889457.html
 
  #16  
Old 08-10-06, 04:27 AM
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Originally Posted by wolfy357
...obviously a grounded duplex provides less of a risk of any appliances or equipment being damaged in the event of a surge (i.e. lightning storm, etc), than a non-grounded one.
The ground does nothing in the event of a surge, unless a surge protector is plugged in and working. If I plug something in with out a surge protector, say a radio, it is not protected from surges, regardless of whether the receptacle is grounded or not.
 
  #17  
Old 02-09-07, 03:01 PM
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New idea for old problem...

Would like to continue discussion here about my grounding issue with a new idea:

I mentioned earlier in this thread that I have the old NM 4 wire (2 white/2 blk in each receptacle). I had decided to run a ground to my receptacles.

Just checkin here, but is it a possibility to take one of the neutrals in a receptacle and just use that for the ground? --assuming I attach to ground screw on outlet and ground terminal at service panel.
 
  #18  
Old 02-09-07, 03:16 PM
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Electrically it is possible (if you do it perfectly and correctly identify which white wire is which at each box), but it is not allowed by code.
 
  #19  
Old 02-09-07, 06:38 PM
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If it's not up to code, I won't do it.
Just curious though, is it even possible to identify which wire would be the correct one at the panel?
I'm not planning on doing it, just seems like you would need some special equipment...
 
  #20  
Old 03-27-07, 08:24 AM
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Adding the ground wire.

I've read thru this thread and have learned some valuable info on grounding. Here's my situation which I would like some advice. I have ungrounded NM cable throughout a small older home I am flipping. I need to provide at least a grounded GFCI on the bath/kitchen circuit, and one to the detached garage circuit. The rest of the outlets can remain ungrounded 2 prong, right?

According to what I've read, I need to run a ground wire from the panel or "the grounding electrode system" to each of the outlets. I don't have a grounding electrode system that I know of, so I assume the panel is my only ground source.

Can I run an uninsulated copper wire of the same gauge, or does it need to be insulated? Or do I need to replace the NM cable with 3 conductor? If it's my choice, which is easier? Obviously, it would be cheaper to just add the ground wire. Any recommenedations on how to accomplish this with the least amount of headaches would be greatly appreciated.
 
  #21  
Old 03-27-07, 08:28 AM
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Why do you think you have to provide a grounded GFCI?
 
  #22  
Old 03-27-07, 08:45 AM
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Its a "flag item" by home inspectors. When I put it on the market I want it to have as few flags as possible. Are you saying its not required?
 
  #23  
Old 03-27-07, 08:53 AM
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GFCI is good. Grounded GFCI is usually not necessary in older homes. The inspector will certainly point out that the receptacles are not grounded, but he's going to point that out all over the house, not just in the bathrooms.

If the inspector is any good, he'll know that GFCIs do not need grounding to provide the protection they are designed to provide.

P.S. Everybody has a grounding electrode system. Some are better than others.
 
  #24  
Old 03-27-07, 09:01 AM
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Home inspectors cannot require you to do anything.

Unless you have local requirements which dictate otherwise, you are not required to have GFCI receptacles in any locations if GFCI receptacles were not required when the house was built or remodeled.

Now a home inspector might very well point out that GFCI receptacles would make the house safer, and a potential buyer might very well want you to install them, so doing so not might save the hassle of installing them later, or negotiating for them, etc. But understand, even if a hoe inspector "flags them", you still donít have to add them. The buyer may require it and you may have to do so to sell to him or her, but that would be your call.

If this were my house, I would have installed GFCI receptacles in the bathroom long ago. Like as soon as I bought the house. The same for the garage, kitchen, any outside receptacles and any unfinished basement receptacles. I would have done this for my safety and that of my family. In your case I would install GFCI receptacles for the same reason, safety.

However, I would NOT run ground wires to any receptacles unless I specifically needed a ground for something. A GFCI receptacle does not need a ground and will work just fine without one.

So to address your situation, I would install enough GFCI receptacles to provide protection to the areas I mentioned. I would do this because they are not difficult to install and it might stave off some red marks against the house. However, I would not go further and attempt to provide grounding for receptacles at this stage of the game. On your panel being grounded, I suspect that it is and you just donít realize it. However, I would certainly verify this, or more accurately I would have verified this when I bought the place.
 
  #25  
Old 03-27-07, 02:59 PM
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Thanks John and Bob for your prompt and direct replies.

Actually, I bought the house 2 weeks ago and want to provide a safe environment for the next owner, without doing more than necessary.

So, if I install a GFCI on the first outlet on the ungrounded branch circuit will everything beyond that point be protected?

Getting back to one of my original questions: If I did want to have a grounded circuit, Can I run an uninsulated copper wire of the same gauge, or does it need to be insulated? Or do I need to replace the NM cable with 3 conductor? If it's my choice, which is easier? Obviously, it would be cheaper to just add the ground wire. Any recommendations on how to accomplish this (fishing the wire thru the walls ) with the least amount of headaches would be greatly appreciated.

PS. the panel is grounded.
 
  #26  
Old 03-27-07, 03:08 PM
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In some older houses, there is no "first" outlet on a circuit. Sometimes the circuit branches out like an octopus. But yes, if there is a first, it'll protect everything downstream.

Grounding wire may either be bare or with green insulation. It should be the same gauge as the circuit (#14 on a 15-amp circuit, #12 on a 20-amp circuit). You may add the grounding wire, but replacing the cable is better and sometimes no more work.

Fishing is an art. Different techniques are used in different situations. Hard to offer advice since we cannot see what you've got.
 
  #27  
Old 03-27-07, 03:25 PM
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thanks for your help, I think I'm on the right track now.
 
  #28  
Old 03-27-07, 03:32 PM
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I just thought of another question. If I install the GFCI on the first outlet and run a ground wire to one or two of the other outlets on the circuit will the GFCI still work properly and protect everything downstream?
 
  #29  
Old 03-27-07, 04:12 PM
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A GFCI does not provide a ground. Running a ground wire from a GFCI receptacle to downstream receptacles will not provide a ground to those receptacles (unless the GFCI is grounded) and would be a waste of money.

Downstream receptacles would be protected, but GFCI protection from has nothing to do with the ground wire, which does not figure into GFCI protection.
 
  #30  
Old 03-27-07, 07:50 PM
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Its a "flag item" by home inspectors.#

Ask for Electrical credentials.


If the inspector is any good, he'll know that GFCIs do not need grounding to provide the protection they are designed to provide.#


Home inspectors cannot require you to do anything.

Unless you have local requirements which dictate otherwise, you are not required to have GFCI receptacles in any locations if GFCI receptacles were not required when the house was built or remodeled.




repman55 Thanks John and Bob for your prompt and direct replies.

Actually, I bought the house 2 weeks ago and want to provide a safe environment for the next owner, without doing more than necessary


Kinda late to ask now.. No?

Past the first time, now sell and move.
 
  #31  
Old 03-27-07, 08:14 PM
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Never too late to ask as long as the house and you are both still standing.
 
  #32  
Old 03-28-07, 09:28 AM
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Originally Posted by repman55 View Post
I just thought of another question. If I install the GFCI on the first outlet and run a ground wire to one or two of the other outlets on the circuit will the GFCI still work properly and protect everything downstream?
Bob, I don't think you understood my question. The ground wire is coming from the grounded electrical panel and connecting to recepticles downstream from the GFCI. I think your answer says GFCI and Grounding are 2 seperate issues and whether any, or some of the recepticles are grounded or not will not interfer with the GFCI's operation, right?

To take it one step further, Can I use the same ground wire from the grounded electrical panel to provide grounds to selected recepticles on different branch circuits?
 
  #33  
Old 03-28-07, 09:57 AM
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Running a grounding wire to a receptacle, either upstream or downstream from a GFCI, will not affect the operation of the GFCI.

Yes, you can use the same grounding wire to ground receptacles from different circuits.

This whole project sounds a bit goofy to me.
 
  #34  
Old 03-28-07, 10:51 AM
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John, Here's what I'm doing with this old house. Replacing the exterior doors and windows, installing central heat and air, replacing the Kitchen cabinets, floor, and appliances and remodeling the bathroom. And now that I know how, making a minor upgrade to the electrical system by adding GFCI to the Kitchen, bath and garage circuits and adding grounds to selected outlets for the appliances, i.e. refrig, microwave, washing machine. Thanks for your help.
 
  #35  
Old 03-28-07, 10:55 AM
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If you do run a separate ground wire for multiple circuits, make sure that the ground wire is sized for the largest circuit size. That means 20 amps (12 gage wire) if one of the circuits is 20 amps.
 
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