No ground (earth)

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Old 09-03-14, 12:48 PM
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No ground (earth)

I'm rehabbing an old 50's kitchen and spent the last few hours setting up to replace the existing countertop outlets with GFI versions. Only problem? I attached the GFI's, only to realize there's no ground! I cut back the old cloth-covering shield, thinking the ground wire may have broken off, but there's just nothing there - just the neutral and hot wires. I can't replace the cable, because I'd have to tear out entire tile-covered walls, so what am I supposed to do now?
 
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Old 09-03-14, 12:52 PM
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Replacing Cable

What type of wall construction (masonry, wood framing,etc)?
 
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Old 09-03-14, 01:00 PM
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A GFI does not need a ground to operate.
 
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Old 09-03-14, 01:10 PM
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@PCBoss.

Oh really? I though it was integral to how it worked. So are you saying I can go ahead and install it without concern for the ground?

I'm also curious - was it standard in older houses to have them wired without grounds? I thought it was part and parcel of home construction since Edison!
 
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Old 09-03-14, 02:44 PM
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The GFI senses the power between the hot and neutral. If not balanced to within about 5mA of current the GFI shuts off.

Grounding conductors didn't start to appear until the late 50's or early 60's. The code did not have the same grounding requirements.
 
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Old 09-03-14, 10:19 PM
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I can't replace the cable, because I'd have to tear out entire tile-covered walls, so what am I supposed to do now?
you do not need a ground wire if you install gfci outlets.
 
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Old 09-04-14, 01:07 AM
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If you have access to unfinished space above or below the new cables can usually be fished with out disturbing the wall except to carefully remove the existing boxes to provide a hole for fishing. The existing wire is abandoned in place not removed in most cases.

In the 50's neither dedicated circuits or 20 amp circuits on #12 wire was required. Doing this will give you twenty first century wiring. Your current wiring is probably just not up to handling modern high amp kitchen appliances such as microwaves.

You may need some additional tips for removing gangable boxes from tiled walls. I'll be glad to make suggestions on doing that mostly using a Dremel tool.
 
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Old 09-04-14, 10:55 AM
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@Ray
Ah, there I'm ahead of you. We have indeed installed a microwave, dishwasher and relocated the fridge, but each unit has had a new dedicated circuit put in, so no problems with old wiring being overloaded. It was a pain in the arse like you wouldn't believe to do it, because the kitchen is tiled from wall to ceilings, so a lot of the usual methods for getting new wiring in place was impossible - and I have the usual electricians tools for doing the job, from the fiberglass poles to the flat 'fishing' wire. What didn't help is that the roof has a very shallow angle to it, so it's almost impossible to move in the attic space (I use that reference as a joke) not least because the AC ducting up there is impossible to climb over - how they even installed it is a miracle! The crawl space underneath is also impossibly shallow for me to work in. The only thing that worked in my favour is that we installed ceiling high cabinets to give as much storage as possible in this very small kitchen, and that allowed me to drill directly up into the ceiling, through the tile, to install the wiring for the microwave - it was the only one of the three items I could wire this way because of the inability to move around in the roof area. For the other two I cut a hole in the wooden floor where the dishwasher is going and had one of my kids crawl around underneath to feed the new wiring from the kitchen to a pre-exisiting hole in the wall by the garage (he'll be talking about that little adventure for weeks!) from where I could then run it across to the main board.

But as for re-wiring this particular outlet, it's a no-go zone because it's completely inaccessible both from below and above due to the issues mentioned before. Had I known beforehand that there was going to be an issue with a ground wire I could probably have made a hole in the ceiling above where the cabinet was installed over this outlet and used one of the fishing devices to reach over the ducting 15' away. But I'm not about to dismantle all the cabinets on that side now, nor do I want to cut a hole in the top of it and then do some half-arsed job of covering over it afterwards with a piece of ply. If push came to shove I'd do it, but I'd rather not at this point, and there's no guarantee that the method would work.

I did happen to be at one of the big box stores yesterday and ran the problem by the resident electrical 'expert', and he claimed that the GFI did indeed need grounding to work and that the only solution he could suggest, given all the details, was to sink a copper spike outside and connect it to the outlet directly through the exterior wall where the kitchen is located. I could actually do that, as it would take little effort to drill a small hole through the siding from the outlet cavity, but gee, does it seem like overkill for one simple outlet that will probably get used for a basic coffee-maker! Especially as it would be a royal pain in the arse to hammer that 6' copper spike into the soil!

So at this point I'll just take on board what's been said here, leave the outlet as is with the new GFI in place, and thank you all for your helpful feedback.

Cheers
 
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Last edited by timbo59; 09-04-14 at 11:30 AM.
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Old 09-04-14, 11:15 AM
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I did happen to be at one of the big box stores yesterday and ran the problem by the resident electrical 'expert', and he claimed that the GFI did indeed need grounding to work and that the only solution he could suggest, given all the details, was to sink a copper spike outside and connect it to the outlet directly through the exterior wall where the kitchen is located.
And everything he said was wrong. In the NEC it actually suggests using a GFCI receptacle with no ground to increase personal safety when no ground is present. True only in that the receptacle is still not grounded and won't provide the ground needed for things like surge protectors but it is in the final analysis an approved method.

The ground his method suggests is a GEC and is not a substitute for the EGC you need. It could technically also be a code violation since all GECs need to be connected together. A Ground Electrode Conductor is to reduce the atmospheric charges at the electrical panel. The Equipment Grounding Conductor the receptacle would need would be a low resistance path all the way to the panel supplying the receptacle. (Dirt is a variable resistance which can not be assumed to be adequate.)
 
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Old 09-04-14, 11:27 AM
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well, I never said I thought it was right - that's why I highlighted the word expert! LOL.

After what was said on here by people I assumed knew what they were talking about, I figured he was either trying to get me to waste money on stuff I didn't need or simply was confused. I just ran it here to see what would be said about it.
 
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Old 09-04-14, 07:44 PM
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well, I never said I thought it was right - that's why I highlighted the word expert! LOL.

After what was said on here by people I assumed knew what they were talking about, I figured he was either trying to get me to waste money on stuff I didn't need or simply was confused
No, he just plain didn't know and doesn't know code either (BUT THINKS HE DOES). It's sad, but the box stores sometimes award the titles of "Expert" or "Pro" on those who have a number of years experience working in a particular store as a way of rewarding them with slightly higher pay for their years rather than rewarding someone who actually knows the code and the industry and can actually help customers by giving them good advice and answering their questions accurately.
 
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Old 09-04-14, 10:33 PM
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I agree with you, but in all fairness I have to say that the HD that's local to me is fortunate to have on staff both an electrician and a plumber who are incredibly helpful and knowledgeable and have really helped me out of a number of jams while rehabbing my own house. I've asked each of them at times why they work at a big box store, and they both said that Florida has become a lousy place to work as true professionals because there's so many fly-by-nighters who work on the cheap, don't have the proper accreditation, and create an environment where they simply can't compete as effectively while trying to maintain the kind of professionalism and standards they're used to - both are in their late 50's early 60's. So for them it's just simpler to take the 'pro' hourly rates at HD, get their all important medical insurance, and keep their hand in by doing some work on the side.

I'd hasten to add though that in my experience both these guys a rarity, as I've gone to many other BB stores where it seems like none of the staff knows a thing, so I consider myself pretty lucky to be able to call on both these guys, as they're always happy to share their knowledge, even when I'm not necessarily buying anything.

The house I'm currently rehabbing is some distance from my home base, so the guy I referred to works at the nearest HD store, not the one near where I live.
 
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Old 09-05-14, 07:17 AM
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I have to say that the HD that's local to me is fortunate to have on staff both an electrician and a plumber who are incredibly helpful and knowledgeable and have really helped me out of a number of jams while rehabbing my own house
Those guys would be the exception and not the typical when it comes to big box stores. For every qualified guy you find, I'd venture to say there are at least 10 who are not qualified to be giving advice.
 
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Old 09-05-14, 02:57 PM
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A neighbor of mine used to work in one of those stores he was a master gardener working in lumber. Nothing like using your resources.
 
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Old 09-06-14, 07:05 AM
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Drilling a hole horizontally through the wall to the outside may very well be a good alternative to breaking up tiles to run equipment grounding conductors. If you drive a spike and the ground and attach the ground wire there, then you must also connect the spike to the existing grounding electrode system using #6 copper wire. At this juncture it becomes a proper ground.

"An otherwise ungrounded receptacle may be replaced with a (3 prong) grounded receptacle where an EGC were run down to the panel with the breaker for that branch circuit, exactly, approximately, or vaguely following the route of the circuit conductors. Should this new EGC first reach a fat ground wire (grounding electrode conductor) running between a panel and a ground rod or running between ground rods it may end and be attached there.""All ground rods being used (for power system grounding, for antennas, etc.) must be interconnected using separately run conductors without sharp bends. The wire size is specified by a table in the National Electric Code but the maximum size ever required is #6 copper. Exception: You may omit wires that have to go over, under, or across lawns etc. to interconnect ground rods at or near different buildings."


Mod note: A ground rod serves no code required purpose for a receptacle so you wouldn't need the ground rod. The separate ground wire back to the panel would be a code approved method however the size of the grounding wire would not need to be larger than the other wires connected to the receptacle.
 

Last edited by ray2047; 09-06-14 at 08:00 AM.
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