So I guess I should choose dual function - but will those work in old wiring (2 wire no ground cable)?
Self-grounding receptacle
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Afjes
Member
wwhitney and jadnashua - have said it correctly with very good explanations.
Both of these types of breakers provide their own unique level/type of protection.
Pay special attention to what wwhitney stated here -
"Breakers can provide both AFCI and GFCI functionality; those are called "dual function" breakers. Not to be confused with "combination AFCI" breakers"
Many DIYers confuse these terms of "Combination" and "Dual" and interchange them. They are totally different from each other.
Yes curiousv - these types of breakers "dual" will provide the protection of both kinds even though your home is old and has no grounds to the receptacles and switches. As a matter of fact replacement of a 2 prong receptacle is allowed to be replaced with a GFCI receptacle or GFCI breaker protecting the entire circuit. So having AFCI and GFCI dual function breaker will be an asset.
Both of these types of breakers provide their own unique level/type of protection.
Pay special attention to what wwhitney stated here -
"Breakers can provide both AFCI and GFCI functionality; those are called "dual function" breakers. Not to be confused with "combination AFCI" breakers"
Many DIYers confuse these terms of "Combination" and "Dual" and interchange them. They are totally different from each other.
Yes curiousv - these types of breakers "dual" will provide the protection of both kinds even though your home is old and has no grounds to the receptacles and switches. As a matter of fact replacement of a 2 prong receptacle is allowed to be replaced with a GFCI receptacle or GFCI breaker protecting the entire circuit. So having AFCI and GFCI dual function breaker will be an asset.
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@wwhitney @jadnashua @Terry @Terry Love @Afjes
This is very imp and serious question.
Even though house has 2 wires - no ground ..they have used a single insulated wire and connected to galv metal water supply lines to provide ground.
I have checked with multimeter and when I connect hot to that single wire or metal pipe - it does show 120v so basically even though it might not be as per modern code - it does work.
Now I am working on bathtub+shower faucet replacement - I have already removed valve so thinking of using PEX pipes partially so it will be mix of galv pipes (which is connected to that ground wire) and partly pex pipes.
When I do that - it will break the ground ? Please check pic so u will have better idea.
This is very imp and serious question.
Even though house has 2 wires - no ground ..they have used a single insulated wire and connected to galv metal water supply lines to provide ground.
I have checked with multimeter and when I connect hot to that single wire or metal pipe - it does show 120v so basically even though it might not be as per modern code - it does work.
Now I am working on bathtub+shower faucet replacement - I have already removed valve so thinking of using PEX pipes partially so it will be mix of galv pipes (which is connected to that ground wire) and partly pex pipes.
When I do that - it will break the ground ? Please check pic so u will have better idea.
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wwhitney
In the Trades
OK, so this is a complicated and serious question. Basically galvanized water pipes and 2-wire electrical cable without grounds are both obsolete products, likely nearing the end of their service life. So the best solution is to remove as much of both as possible and replace them with modern piping and modern electrical cable with a grounding conductor.
Now, on the electrical side, there is still an allowance for taking a circuit supplied by ungrounded wiring and retrofitting a separately run grounding conductor to ground the circuit (and receptacles, etc on it). It's just no longer allowed to run that wire to metal wire piping, because of the advent of plastic water pipes and the resulting uncertainty of the maintained continuity of the water pipes. Instead you have to run it to one of the locations listed in NEC 250.130(C):
Of course for a given receptacle you might want to retrofit with a grounding conductor, if you can run to one of those locations, you typically can just as easily run a new cable to a panel, which is a better solution. However, you have the existing separate grounding conductor to deal with.
So the minimum that you should do is extend that grounding conductor to one of the locations listed above. The splice in the grounding conductor should be in an accessible electrical box, so you'd need to find a place where you can put that. Or you could trace the grounding conductor to its other end and simply replace it starting there.
Cheers, Wayne
Now, on the electrical side, there is still an allowance for taking a circuit supplied by ungrounded wiring and retrofitting a separately run grounding conductor to ground the circuit (and receptacles, etc on it). It's just no longer allowed to run that wire to metal wire piping, because of the advent of plastic water pipes and the resulting uncertainty of the maintained continuity of the water pipes. Instead you have to run it to one of the locations listed in NEC 250.130(C):
https://up.codes/viewer/california/ca-electric-code-2019/chapter/2/wiring-and-protection#250.130_(C)
Of course for a given receptacle you might want to retrofit with a grounding conductor, if you can run to one of those locations, you typically can just as easily run a new cable to a panel, which is a better solution. However, you have the existing separate grounding conductor to deal with.
So the minimum that you should do is extend that grounding conductor to one of the locations listed above. The splice in the grounding conductor should be in an accessible electrical box, so you'd need to find a place where you can put that. Or you could trace the grounding conductor to its other end and simply replace it starting there.
Cheers, Wayne
Jadnashua
Retired Defense Industry Engineer xxx
Galvanized pipe is a problem waiting to happen. Using it as a reliable ground just isn't reliable as it rusts and modifications to the home are made.
Usually, when you modify things in the home, they require the things you touch to be brought up to current codes. The rest is grandfathered AS LONG AS YOU DON'T TOUCH IT!
If you use a GFCI device, any receptacle downstream is allowed to be replaced with a grounded one for convenience AS LONG AS YOU PUT THE REQUIRED STICKER ON IT. That sticker says something like "GFCI Protected, no equipment ground". There's usually a supply of them in the GFCI package. Some things won't work properly without an actual ground, like a surge suppressor which can't achieve its full capabilities without one.
Usually, when you modify things in the home, they require the things you touch to be brought up to current codes. The rest is grandfathered AS LONG AS YOU DON'T TOUCH IT!
If you use a GFCI device, any receptacle downstream is allowed to be replaced with a grounded one for convenience AS LONG AS YOU PUT THE REQUIRED STICKER ON IT. That sticker says something like "GFCI Protected, no equipment ground". There's usually a supply of them in the GFCI package. Some things won't work properly without an actual ground, like a surge suppressor which can't achieve its full capabilities without one.
@jadnashua - Thanks I have heard loud and clear and multiple times about galv pipe and nearing its life and not modern codes.
But Please listen - I can't want to have major expense - I just want to fix things with min. possible and still as per code.
I know its possible -
@wwhitney - Thanks again - U said run/extend a grounding conduction to one of the location listed above - I believe you are referring to locations mentioned in NEC 250.130(C)
But its too technical for me - can you give me an example of those locations in layman terms...
I think you made it clear that those metal water supply lines can not be one of those allowed location.
Please look at my pic above so u have a better idea.
I understand if I splice this ground wire shown in pic that is attached to that water pipe - it has to be in jn box - and I can put one jn box - on that stud itself on which this grounding wire is stapled to.
But after I make that splice/connection and put a new extending grounding wire - where would I put the other end ?
As I said in pic ...there will be some metal parts in plumbing system on top of those metal supply galv pipes. for example - a brass elbow or metal bend support - also on top there will be shower head which is metal I believe and the mfg specifically says the tub spout pipe must be ips or copper so that will be metal.
So I connect this extension wire to every point that is metal? and than further extend it out to one of those allowed locations mentioned in NEC 250.130(C) ?
But Please listen - I can't want to have major expense - I just want to fix things with min. possible and still as per code.
I know its possible -
@wwhitney - Thanks again - U said run/extend a grounding conduction to one of the location listed above - I believe you are referring to locations mentioned in NEC 250.130(C)
But its too technical for me - can you give me an example of those locations in layman terms...
I think you made it clear that those metal water supply lines can not be one of those allowed location.
Please look at my pic above so u have a better idea.
I understand if I splice this ground wire shown in pic that is attached to that water pipe - it has to be in jn box - and I can put one jn box - on that stud itself on which this grounding wire is stapled to.
But after I make that splice/connection and put a new extending grounding wire - where would I put the other end ?
As I said in pic ...there will be some metal parts in plumbing system on top of those metal supply galv pipes. for example - a brass elbow or metal bend support - also on top there will be shower head which is metal I believe and the mfg specifically says the tub spout pipe must be ips or copper so that will be metal.
So I connect this extension wire to every point that is metal? and than further extend it out to one of those allowed locations mentioned in NEC 250.130(C) ?
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Today I tested this GFCI outlet with a GFCI plug tester and like u said - it did not trip ...actually it showed fault that it has reverse polarity so I checked and black-hot is connected to brass screw and white is connected to silver screw -
Later I checked with test button and it does trip and all the downstream i.e. load connected devices turned off..but to my surprise a three way switch ..which is connected to load side ..did not turn off...can you tell me why?
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wwhitney
In the Trades
No, sorry, I think this is the point where I suggest you contact an electrician to help you with this. The ramifications and your unknown unknowns are potentially (so to speak) too significant for piecemeal guidance over the Internet.
Cheers, Wayne
Ok thanks for ur help/discussion until now
Afjes
Member
Do you have metal boxes? If you do just because you don't see a ground wire in the box does not mean the box is not grounded. Old style of wiring was to wrap the ground wire around the strain relief (clamp) in the back of the box (out of your site looking into the box). If the box is grounded but you don't see a ground wire the plug in tester will trip the GFCI receptacle or breaker. Also, sometimes the ground wires in a metal box are cut very short and a small portion of the ground wire is tucked under a screw of a clamp in the back of the box which can be very diffcult to see. One would think the box is not grounded but in fact it is.
A meter connected to the box and the hot wire will tell you right away. There are other ways a box can be grounded without you seeing it like if conduit is being used but I just wanted togive you a few examples.
Jadnashua
Retired Defense Industry Engineer xxx
Modern BX usually has a ground lead, but older stuff did not. The casing was often used as a safety ground, but that often ends up rusting, and the connection is spotty or gone, especially if the box is in a plaster wall.
Thanks,
I checked with multimeter and when I connect hot to one lead and another lead on metal box or any screw - it shows 66V - I know it has to be 120v - what could be reason ? I checked 2 boxes on that circuit and both shows 66v - same v
Surprisingly even though it indicates no proper ground - when I press GFCI outlet test button it always trips without fail.
Now I am thinking instead of relying on GFCI outlet for ground protection - I should switch the breaker with dual fn gfci+afci combo breaker ...but I am worried because this house has no ground wire in old cables - that breaker will trip so frequently that I have to change it again to normal breaker...any opinion on this?
Afjes
Member
curiousv - What do you get at the breaker for this same circuit you are now getting 66v from the receptacle?
If you are getting 120v at the breaker on this circuit then somewhere in between you have a loose neutral. It will be more than likely at your last working receptacle on this circuit. Check your connections on the receptacles on this circuit. Make sure no backstabs are used. If any backstabs move to the screws of the receptacles. Even a loose neutral on one of the backstabs on the receptacle in line could cause a reading like this.
It is also possible that you may be getting phantom voltage reading since you are using a digital meter. But let's first go with a loose neutral possibility.
A dual function AFCI/GFCI breaker will provide the same GFCI protection as a GFCI receptacle except it will provide GFCI for the entire circuit. Does not matter if the circuit is grounded as it will function as it should even though no ground. However changing your breaker may not fix your 66volt issue if the issue is at one of the receptacles in the circuit.
Don't change breakers yet. Making too many changes on this circuit before you can determine the problem with the circuit will just complicate the issue and make troubleshooting the circuit even more difficult. Take one step at a time.
If you are getting 120v at the breaker on this circuit then somewhere in between you have a loose neutral. It will be more than likely at your last working receptacle on this circuit. Check your connections on the receptacles on this circuit. Make sure no backstabs are used. If any backstabs move to the screws of the receptacles. Even a loose neutral on one of the backstabs on the receptacle in line could cause a reading like this.
It is also possible that you may be getting phantom voltage reading since you are using a digital meter. But let's first go with a loose neutral possibility.
A dual function AFCI/GFCI breaker will provide the same GFCI protection as a GFCI receptacle except it will provide GFCI for the entire circuit. Does not matter if the circuit is grounded as it will function as it should even though no ground. However changing your breaker may not fix your 66volt issue if the issue is at one of the receptacles in the circuit.
Don't change breakers yet. Making too many changes on this circuit before you can determine the problem with the circuit will just complicate the issue and make troubleshooting the circuit even more difficult. Take one step at a time.
As it should even though there may not be a ground present.
What do you get when you test hot to neutral on the receptacle? If you are only getting 66v on the box to hot then it may be the box is not grounded and your self-grounding receptacles won't make any difference as the box needs to be grounded to have the self-grounding receptacles be grounded - again the self-grounding receptacle just makes it so you don't have to run a wire from the box(or the cable if a ground is present in the cable) to the receptacle. It does not ground you receptacle at all if there is no ground present to begin with in the circuit. This is the mis-conception that many DIYers have.
Jadnashua
Retired Defense Industry Engineer xxx
If you don't have a continuous ground lead from the panel, a metal box isn't properly grounded, and you'll likely measure some voltage with a digital meter. 66v implies a phantom voltage that may not be able to supply much of any current. A self-grounding receptacle in a system without a continuous ground from the panel won't hurt anything, but won't do anything, either.
Thanks a lot for help/discussion.
I checked panel for all the circuits with breakers are ON posiiton(some circuits are off currently) one lead at hot screw on breaker and other on screw where ground wire is connected ( at neutral+ground bar) ...checked like 4 times and all of them show 120v so I guess it implies we have a good ground at panel but something along the path or at at the box where I am checking has problem.
You asked about V between hot and neutral at outlet - that is always 120v and all circuits - all outlets but when I put one lead in hot and other on plastic box - only like 10V - does it mean box is not grounded?
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Jadnashua
Retired Defense Industry Engineer xxx
The only place where ground and neutral should be connected is at the main panel. Your devices want 120vac between the black and white connections...they don't care about the ground except for safety and it doesn't need to be connected at all for them to receive power. Ground is for safety, not for powering the device. It gives an alternate path to pop the breaker or blow the fuse if things get crossed, but normally should NEVER have voltage or current on it.
Thanks but I gave my results in response to @Afjes asking me to check ground at panel/breaker - and all the circuits showing 120v at breaker.
I am not sure what are you trying to convey here?
Afjes
Member
A plastic box is nonconductive. You will never get any proper reading placing one probe on the hot wire and the other on the plastic box. Plastic boxes don't need to be grounded because they are nonconductive. Any receptacle box that you have to check and the box is plastic you place one probe on hot wire and the other on ground (if there is a ground wire) and then you also test hot wire to neutral.
Also, using a self-grounding receptacle in a plastic box does not solve your problem of not having a grounded receptacle. This is a big misconception that many DIYers have. A self-grounding receptacle just makes it easier to provide a grounded receptacle so that you don't have to take your ground wire from a metal box to the receptacle itself. If your circuit is not grounded a self-grounding receptacle will do absolutely nothing to give you any type of a ground. If your box is plastic and the incoming power cable does not have a ground wire then your alternative is to install a GFCI receptacle (NEC approved method). This will not provide an actual ground but is used for personal safety to prevent electrocution. Any box that you install a self-grounding receptacle in must be metal and grounded or the self-grounding receptacle has no meaning at all.
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As per your advice - I checked voltage at breaker ..and it shows 120v - may be you did not read that ..post no. 35 - .any response?
May be I did not check it correctly ?
Afjes
Member
I looked at your photo #35. Kind of hard to see with my 66 yo eyes. It seems to be moderately newer panel. If main panel the ground and neutral should be bonded together. If you are getting 120v at the breaker to the ground/neutral bar then that is correct.
I am starting to lose the meaning of this thread.
These circuits look newer. They should have grounds on them. How many wires does the incoming cable have in a receptacle box. If it is 3 total (one hot - usually black, one neutral = usually white and one bare ground) then your circuit is grounded. You should get 120v from hot to neutral and from hot to ground. If using a plastic box you can use the self-grounding receptacle but you will still have to run a ground wire from the ground on the incoming cable to the receptacle because again the plastic box is nonconductive so self grounding receptacle will do nothing in this case. Also be sure you bound all ground wires together in the box.
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