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GFCI Open Ground and Water


carle3
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Is an open ground on a GFCI receptacle that is installed in a 2 wire system and is within 6ft of a water source a safety hazard?

No. A GFCI-protected, ungrounded receptacle is far safer than a non-gfci-protected grounded receptacle.

Why do you mention 6 feet? Is this a laundry room, utility room or wet bar?

- Jim Katen, Oregon

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Originally posted by zeb

Isn't the two wire system itself a hazard near water,,,,,

Any electricity, grounded or not, is a hazard near water. That's why we have GFCIs, to protect us against ground faults.

And GFCI is intended for a 3 wire system.. ????

No, no, a thousand times, no.

GFCIs work just fine on two-wire, ungrounded systems.

They do not need a ground to work.

They do not work better with a ground.

What if the GFCI was wired wrong and we didn't know it and knew it was a 2 wire system.

With the new GFCI technology, it's nearly impossible to wire one wrong. They won't energize unless the wiring is correct and if they become damaged, they default to the off position.

GFCIs provide greater protection against electrocution than plain grounding ever can.

- Jim Katen, Oregon

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Hi Jim,

Yes the point of conversation revolved around an ungrounded GFCI at a kitchen sink or bathroom sink situation. As a rule I call an ungrounded 3 prong outlet on a 2 wire, or 3 wire for that matter, that is at the kitchen, laundry or bathroom sink a safety concern. Our point of disagreement came when a GFCI was involved. I was at a seminar over the weekend and this discussion brought other inspectors into the debate, at which time I realized what I thought was a cut and dried issue was not. Now I am curious as to how divided this debate may be.

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Carl,

Yes, always call out a "3" prong plug in a "2" wire setup......unless their is a GFCI involved in this circuit in question. Jim was so right ( and I was waiting for someone to say it ) that grounded or ungrounded near water is still the same safety concern. The elevated concern with 2 wire setups is no low impedence fault current path....so this is why their is an allowance in the NEC to protect a "3" prong receptacle placed on a "2" wire setup..if protected by GFCI.....to increase the safety aspect.

I would be VERY interested in hearing from you about this seminar that caused confussion...it should not as it is cut and dry in my opinion on the safety aspects of the GFCI......at the nominal protection factor of 5MA which it will protect against personal injury....However it is important to know that not even GFCI's are perfect....grab a hold of the Neutral wire and be apart of the circuit and the GFCI wont help you much.....or grab between the ungrounded and grounded and see that the GFCI wont help you much so it is still a COMMON SENSE thing when still dealing with GFCI's...they are not failsafe devices.

Education is so important....educate the client on GFCI's, their function as you do the walk around if you get the chance....sends a good message to the client and helps spread proper information on the products.

FYI- Having a "3" prong receptacle on a "2" wire system sends the wrong message to the consumer that 1.) Electrical upgrades have been made when really they have not and 2.) Gives the client a false sense of additional safety by having a low impedence falut current path...which is simply not the case.

Hope this helps.......

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Hi,

You keep going back to this idea of a "2 wire" versus "3 wire" system, but there is no such distinction. All electrical systems are 2-wire systems, except those after the early 1960's added a non-current-carrying equipment grounding conductor. The circuits are still considered 2-wire systems.

As Jim said, all electricity is hazardous around water. The addition of an equipment grounding conductor - the 3rd wire you keep referring to - hasn't changed that one iota. The EGC doesn't factor into whether the cable is going to carry power or not, it's simply an alternative path back to earth for electricity in the event the grounded (neutral) conductor is compromised.

Neither does the addition of a GFCI receptacle change the hazard. The hazard still exists after the GFCI receptacle is installed and after it trips, but the means to harm you - power to a device through a plug and cord - has been neutralized, insofar as the GFCI receptacle has severed the electricity's path back to earth. The outlet is still sitting there wanting to electrocute you, it's just frustrated by the traffic cop (GFCI) who noticed that there were too many electrons traveling down the street in one direction and decided it was time to stop traffic before someone got hurt.

The equipment grounding conductor really doesn't have a thing to do with making the receptacle any more or less of a hazard. After all, if it did, wouldn't it make sense that every single device should have a 3-pronged plug and all 2-pronged plugs would have been banned decades ago? The EGC is a convenience, and a requirement, but, until there is actually an issue with the grounded (neutral) leg of a circuit, its essentially doing nothing. It's doing nothing before the GFCI trips and it does nothing after it trips.

One's proximity to a sink doesn't change the fact that there's a hazard at receptacles. The proximity issue deals with the fact that the likelihood that someone could be electrocuted is increased when a person is in a place where their body can somehow become the path of least resistance for voltage to return to earth. The same hazard exists in a home where there are radiators doesn't it? Someone plugging a faulty appliance into a receptacle that's next to a radiator is at just as much risk as someone plugging an appliance into a receptacle next to the kitchen sink, because they're just as likely to get zapped by touching the fondue dish in the dining room with one hand on the radiator as they are at a kitchen sink.

If someone wants to argue that the inclusion of GFCI protection on any circuit lessens the hazard associated with circuitry, they should argue that only a GFCI breaker does so, because it completely cuts off power to the entire cable feeding the receptacle, instead of leaving it idling there revving it's engines and still raring to go.

I don't know whether I've helped or made things worse. Probably worse. I should never try and explain electrical issues. They're as abstract and foreign to my one-sided brain as mathematics, financial matters and computers.

ONE TEAM - ONE FIGHT!!!

Mike

P.S.

After I posted this, I saw that Paul had responded better than I could and I noticed that I hadn't spoken to whether I call out circuitry that hasn't got an EGC, so I thought I'd edit this and answer that.

I do,....always. Even when not around water. If it's an older home with 2-hole receptacles, or it's pre-1962 (or was it 63?), chances are some homeowner, frustrated with trying to make 3-pronged plugs work on 2-hole receptacles is going to trot down to the big box, buy a handful of 3-hole receptacles and then go home and swap a bunch of them out, so he can use all of his stuff with 3-pronged plugs whenever and wherever he wants. So, knowing that's going to happen, I invariably recommend folks either upgrade their wiring or install GFCI's, to at least mitigate, but not completely eliminate, some of the potential hazard involved.

Hope I'm making some kind of sense here. I'm starting to feel like I'm rambling. Always happens when I try to sound like I know sumpin bout 'lectricity.

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The equipment grounding conductor really doesn't have a thing to do with making the receptacle any more or less of a hazard.

Hmmm, electricity at the potentials we normally find in a home is hazardous. All of the regulations in the world doesn't make it safe and just mitigates the dangers involved.

Is that a correct statement?

Clients will often ask, "Is the electrical system safe?"

If the system is to code how do you reply to that question?

Chris, Oregon

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See this is a good discussion. I am a product of the inspector schools so some of what i base an observation on is a carry over of that.

I do make note of all ungrounded plugs.

I feel in the case of a appliance plugged into an ungrounded outlet, in the instance of a fault that the energy potential will stay at the appliance until given a path. Since the objects most likely to provide that path would be the plumbing fixtures I list that threat as a safety concern.

In the bedrooms and living rooms that condition is less likely to occur. I do list it but gear that more to the damage it can cause electronic equipment and surge suppressors.

This is why I found this topic so interesting to discuss. When we began talking about this I found as a group we were all over the board on our views and understanding of the ground its purpose and the why we call a ungrounded plug GFCI or not a safety concern at kitchens and baths and not when found in a living room.

Oh Paul, the seminar was one for the Wisconsin Association of Home Inspectors but the discussion was over a few beers and not part of the presentation.

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lol...I got ya Carl....well I for know exactly what a few beers and "Electricity" chat can evolve into...lol

Basically I did want to comment about the EGC....( which I personally think should be renamed to EBC ) but thats just me....anyway I digress......

The function of the EGC is to ensure a fault current path back to aid in clearing a fault upon any metalic structure that may be energized...without that path you are relying on another path...be it the grounded conductor...which already has current upon it as the return path....so having a properly done EGC within a system is always safer......I will argue that until I am blue in the face.....now with that said...we see alot of appliances that have no EGC terminal at all on the equipment...why is that...well many times because of no metal parts exposed or double insulated cords and such.......but thats a whole different topic and I am always warned by the powers that be to NOT get overly technical so I wont.....:)

But in my mind.....their are plenty of 2 wire and 3 wire systems........we as HI's see alot of older setups with only 2 conductors and no EGC all the time...yet they give the false impression of being upgraded or providing that fault current path back to aid in clearing a to case/metal enclosure ( for example ) fault.......anyway I don't want to harp on it but I hear it alot....all systems are grounded because they have the Neutral connection....BUT that is not the fault current path we are looking for when the EGC was introduced........and it was introduced for a reason...

Dang...now I am rambling....see what you started Mike..

To Chris - The "CODE" is the minimal standard and meeting that standard makes it safe but not the safest it could be but you have to start somewhere...right. As for Safe....just remember it only takes 8-10MA to LOCK on and not let go.....and remember the smallest circuit in the dwelling is a 15A circuit......you do the math......electricity is dangerous no matter how you slice it.

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I'm going to try to keep my reply short. Lets see if it works... GFCI with an open ground is ok and will provide the intended shock protection. Without the ground, to induce a ground fault into, our testers can not make them trip but the test button on the outlet should. And what no one else has touched on, I think (my eyes are getting bleary looking at all this) is that it is fine as long as the receptacle is labeled as ungrounded. I always tell my clients it is ungrounded and will function fine for shock protection but will not afford grounding of appliances that have a three prong plug. As Mike said, so long as you are only plugging in a two prong plug - to a properly polarized receptacle - the two wire is no more dangerous then anything else. I just always advise my clients that using a three prong:two adapter will let them plug it in but will not ground the appliance that needs one to keep it's casing at zero potential.

That said -- Electricity & Beer. Oh yes!

Jim

"With the new GFCI technology, it's nearly impossible to wire one wrong. They won't energize unless the wiring is correct and if they become damaged, they default to the off position."

Have they finally updated the standards? If the protection fails the outlet provides no power? About time if they did... Where did you get that from, I need to keep up more on my current (no pun intended) events.

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Originally posted by Kyle Kubs

I'm going to try to keep my reply short. Lets see if it works... GFCI with an open ground is ok and will provide the intended shock protection. Without the ground, to induce a ground fault into, our testers can not make them trip but the test button on the outlet should. And what no one else has touched on, I think (my eyes are getting bleary looking at all this) is that it is fine as long as the receptacle is labeled as ungrounded. I always tell my clients it is ungrounded and will function fine for shock protection but will not afford grounding of appliances that have a three prong plug. As Mike said, so long as you are only plugging in a two prong plug - to a properly polarized receptacle - the two wire is no more dangerous then anything else. I just always advise my clients that using a three prong:two adapter will let them plug it in but will not ground the appliance that needs one to keep it's casing at zero potential.

That said -- Electricity & Beer. Oh yes!

I'm with you so far. While we're on the subject, it's always a good idea to remind people that, if they plug a surge protector into an ungrounded, GFCI-protected receptacle, the surge protector won't protect against surges.

Jim

"With the new GFCI technology, it's nearly impossible to wire one wrong. They won't energize unless the wiring is correct and if they become damaged, they default to the off position."

Have they finally updated the standards? If the protection fails the outlet provides no power? About time if they did... Where did you get that from, I need to keep up more on my current (no pun intended) events.

Douglas Hansen explains it very well in this article:

Download Attachment: icon_adobe.gif GFCI Stds Rev 2006 .pdf

100 KB

- Jim Katen, Oregon

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Jim,

What I found is that depending on where you are in the country the GFCI's failed more than others because of surges imposed on the GFCI's and to be honest...failing the MOV of the GFCI itself.

I also believe the newer advent of the UL943 goes along way to solving alot of the problems with older GFCI's, Many times these devices would simply fail and when they did they did so in the closed position and the receptacle worked but offered no GFCI protection....very misleading and unsafe and good to say the industry leaped to correct this problem.

In the end the only effective way to keep devices and equipment safe from surges or high voltage inrush things like lightning is a whole house system....located at the panel itself.

FYI- the " case potential " is a misnomer....but if it helps people sleep at night thats ok....not the intent of the EGC in the electrical system.

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Mike -

Way back up in this thread you stated "If it's an older home with 2-hole receptacles, or it's pre-1962 (or was it 63?)"

What exactly is it that you are referring to here?

Was it 62 or 63 that 3-hole receptacles were introduced?

How about thermoplastic insulation...was that introduced around 65?

I find timelines very helpful as I sort out the original equipment in homes for updates. I usually have the year built from the MLS listing. Sometimes it is accurate, other times it is not.

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Hi,

I was trying to remember which year the NEC began requiring EGC's on all 15 and 20 amp receptacles. I just looked it up in Doug Hansen's book. I was right the first time - it was 1962. According to Hansen:

1951 NEC - Only the laundry required grounding type receptacles.

1956 - First requirement for grounding type receptacles at exteriors, garages and basements.

1959 - First requirement for grounding type receptacles at kitchen sinks.

1962 - All 15 & 20 amp receptacles required to have grounding type receptacles.

According to Hansen, thermoplastic wasn't used until the 1960's. He even shows a photo of thermoplastic used in a rare knob-and-tube installation that was done in the 1960's with thermoplastic insulation on the wires.

ONE TEAM - ONE FIGHT!!!

Mike

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Thanks Mike - Things to do today:

1. Finish reading Hansen's book...just arrived.

2. Finish reading all historical home threads in preparation for my 1827 built next week -

- Historical House Inspection @ standard fees - stocked trout pond inspection - no charge (catch & release protocols to be followed)

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Originally posted by PAbernathy

Jim,

What I found is that depending on where you are in the country the GFCI's failed more than others because of surges imposed on the GFCI's and to be honest...failing the MOV of the GFCI itself.

Yeah, there's definitely a regional component. Areas with lots of lightning strikes seemed to have a much higner incidence of GFCI failure. But sometimes they'd fail for no particular reason. Up here we have very little lightning. (When we do get some, the run pictures of it in the paper.) Yet the old technology GFCIs failed at an alarming rate. I have yet to find a new technology one that's failed in the closed position. Have you?

Also, I have no proof of this, but I believe that a lot of older GFCIs failed because of exposure to moist conditions.

I also believe the newer advent of the UL943 goes along way to solving alot of the problems with older GFCI's, Many times these devices would simply fail and when they did they did so in the closed position and the receptacle worked but offered no GFCI protection....very misleading and unsafe and good to say the industry leaped to correct this problem.

I'll take this opportunity to boast that home inspectors had a lot to do with that decision. Data that led to the decision was gathered by home inspectors in the field and was published in IAEI News.

In the end the only effective way to keep devices and equipment safe from surges or high voltage inrush things like lightning is a whole house system....located at the panel itself.

Sure. I put one in my house in 1992. Of course it may be another 20 years before the poor thing actually sees a surge.

FYI- the "case potential" is a misnomer....but if it helps people sleep at night thats ok....not the intent of the EGC in the electrical system.

I musta been sleeping. Who mentioned case potential and what did they say about it?

- Jim Katen, Oregon

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So Dave,

What's the copyright date on your Hansen book??? Mine is 2005. Yours is newer?

Originally posted by dtontarski

Thanks Mike - Things to do today:

1. Finish reading Hansen's book...just arrived.

2. Finish reading all historical home threads in preparation for my 1827 built next week -

- Historical House Inspection @ standard fees - stocked trout pond inspection - no charge (catch & release protocols to be followed)

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Thanks Dave!

Yep, mine is the same. For such an excellent book, I'd expect more fanfare with a newer edition available. Maybe it hasn't made it to the printers yet.

Originally posted by dtontarski

Gary,

Copyright 2001, 2005 - 3rd printing. I ordered the new one (see my earlier post) and they sent me this one. Strangest on-line ordering experience I've every had. Mine is likely the same one you have.

Dave

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I may be dumb as a pile of rocks,,but if on a 2 wire system and a ground fault outlet and I stick my handy dandy tester in it and I see the center light come on (ungrounded??) I then press my super handy dandy tester button and nothing happens, then the outlet is not working proper for gfci??? My question is will a tester trip a GFCI on a 2 wire system. Jim I know that that this is small stuff for you along with many others,,however I may have been sleeping during this part.

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