Adding ground wire from old 2-prong outlet to copper pipe - code compliant?

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K9mlxj

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Hi,

Is running ground wire in the crawl space from old 2-prong electrical outlet (clamped) to copper piping NEC code compliant? It's 100% copper piping in the house, and the copper piping goes underground 16 inches and runs for 60 ft before it gets to the water meter by the curbside.

I suppose that copper piping is considered a legitimate ground rod.

I wonder if I can clamp the ground wire anywhere along the copper piping . Or it has to be close to the entrance of the house to comply to NEC code?

Another way if this doesn't work, is to run ground wires from all the 2-prong outlets to a single bus bar, and then run a single ground wire from there to the main panel.


I have GFCIs in some of the bedrooms. Good to still keep them installed, or no need after grounding is available for those outlets?


Thanks.
 
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Reach4

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As I understand it, no. The ground wire needs to run back to the breaker box.
 

Stuff

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They did that in the old days but is not legal now. For copper pipe I believe it has to connect within 5 feet of coming into the house. That assumes that there is a wire (GEC) that bonds the water pipe with the electrical panel.

(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) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates
(5) For grounded systems, the grounded service conductor within the service equipment enclosure
(6) For ungrounded systems, the grounding terminal bar within the service equipment enclosure
 

Cacher_Chick

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noequipmentgroundlabeloncoverplate.jpg
Using the plumbing is not permitted, but it is allowed to replace the ungrounded receptacle with a GFCI receptacle that is marked "No Equipment Ground".
 

K9mlxj

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I need to bring in ground wire to each ungrounded receptacle as I want to install surge protectors at the outlets to add surge protection.

They did that in the old days but is not legal now. For copper pipe I believe it has to connect within 5 feet of coming into the house. That assumes that there is a wire (GEC) that bonds the water pipe with the electrical panel.

(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) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates
(5) For grounded systems, the grounded service conductor within the service equipment enclosure
(6) For ungrounded systems, the grounding terminal bar within the service equipment enclosure

So to be clear, it'd comply with NEC, if I connect the ground wire to within 5 feet of the copper piping coming into the house.


Would this following setup work?

Add ground wire from each ungrounded receptable location -- to a central bus bar (under the crawl space fastened to a foundation beam for example).

Run a single wire from this central bus bar:

- back to the main panel, OR
- to the copper piping within 5 feet of entrance into the house, OR
- to connect to the bonding wire (through another bus bar, or just add a splice?) that runs between the copper piping and the main panel

Would all of these connection methods work?


Also, to bond the the copper piping to the main panel, the water piping entrance is 30 ft away from the main panel.

With latest NEC code there needs to be an IBT near the main electrical panel visible on the outside wall. So I wonder, this bonding wire from the copper piping needs to run

- along the outside wall -- to the IBT, OR
- I can run it under the crawl space inside the house and back out to the IBT on the outside wall, OR
- I can run it straight to the main panel, and not needing to connect to the IBT?
 
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Stuff

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OK. So with needing surge protectors the GFCI outlets don't help much. There are some like SurgeX that say they protect without a ground but still operate better with one.

All codes I know of required bonding metal water supply pipe to service panel ground, sometimes it is done indirectly so you need to poke around a bit.
All three methods you listed would work with a central bar. Most would expect to go to the panel though.
The connection from copper pipe would normally go to the panel. It can go to GEC wire that connects grounding rods. The IBT is not meant for this.
Do not splice the GEC/bonding wire as it is supposed to be continuous. If you need to they make taps.
 

Jadnashua

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The copper pipe in your house should be bonded to ground, but should not be THE ground for the system...using the piping as a ground can end up dangerous to anyone that may do some plumbing work. If you have a fault somewhere that puts current on your pipes to ground, that can cause your water heater to wear out quite fast or, hurt someone if they needed to cut the piping for maintenance or modifications.

If you require grounds at your receptacles...you really should rewire the house with new cables.
 

K9mlxj

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(4) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates

For this one, I can essentially run a ground wire from one ungrounded outlet to connect to the ground wire in a grounded outlet from another branch circuit (having same amp rating)?


All three methods you listed would work with a central bar. Most would expect to go to the panel though.

Don't really want to have a dozen grounding wires all over crawl space running all the way back to the panel. Trying to reduce too many wires in the crawl space and going to the main panel.

Also want to confirm there's no restriction for multiple bus bars?

Say I have bus bar A where area 1 and area 2 outlet grounds connect to, and bus bar B serves area 3 and area 4 outlets grounding. Then I'd have ground wires from bus bar A and bus bar B connecting to a final central bus bar C. And then one ground wire from bus bar C runs to the main panel.

Area 1, 2 -> bus bar A
Area 3, 4-> bus bar B
bus bar A, bus bar B -> bus bar C

bus bar C -> main panel

That'd work fine as well?


Would be fine the ground wires keep flush and right underneath the subfloor wood pranks? I hope any contractor who does subfloor work won't accidentally cut into these wires if they need to cut off section of subfloor for remodeling/repair work.
 
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Stuff

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Connecting to a ground from another circuit is a recent addition but makes a lot of sense. Strangely no restriction on amperage.

The NEC isn't clear on all the details. Technically all splices/connections are supposed to be in a box and a bus bar is just a big splice point. Code doesn't address the issue but should be good as it is more like a GEC splice that is exposed. Make sure to use #14 cu wire for 15 amp, #12 for 20 amp circuits.

Treat the ground wire like NM cable. Wiring should be 1 1/4" from edge of boards so protected from nails. Usually easiest to attach to center side of joists. Or use a running board.

You could talk to the local inspector as may want insulated green wires or other local requirements.
 

K9mlxj

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Great thx for everyone's help.

All the current outlets in this house are 20A circuits (only ceiling lights all go to one single 15A circuit), so it'd be #12 AWG wire for the whole setup. Good idea on the joist, so it'd be easy to locate the buses as well.
 

Jadnashua

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Let us know what your inspector says about this...it's my understanding that the ground must be in the cable (or conduit, if using say THNN), and not an add-on. From a functional viewpoint, if the ground does get back to the panel, it should work. There should be NO current on the ground lead, it is there to provide an alternate path to trip the breaker or blow the fuse if there's a problem...otherwise, it just sits there. ANd, I think you'll find a slightly smaller gauge wire than the current carrying conductors is allowed. Because any current on that line would only be momentary, it shouldn't heat up, so the smaller gauge wire is sufficient to trip the safety device.
 

K9mlxj

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Hi,

I wonder if this other arrangement would also work:

converted 3-prong outlet 1 -> (ground wire) -> converted 3-prong outlet 2
converted 3-prong outlet 2 -> (ground wire) -> converted 3-prong outlet 3
converted 3-prong outlet 3 -> (ground wire) -> bus bar A

bus bar A -> (ground wire) .... -> main panel

It should function the same way. Ok with code?


Also, once this is done,
I can then extend any of these circuits with NM-B cables to have new grounded receptacles, since all the converted old outlets are then grounded?
 
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Jadnashua

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If a device is properly grounded, then yes, you could extend it to generate additional grounded devices, but I've been led to believe, the original ground MUST be in the same cable or conduit as the power leads and run back to the power panel...you're bus bar wouldn't cut it if I'm interpreting it properly. Functionally, if it was all done well, yes it could work. The issue is, when you have a single cable, if you need to do some work, you know that if you break the ground, it won't affect potentially numerous other devices that aren't obviously in the same chain. When you run a separate ground, then distribute it to who knows where, someone down the line could disconnect it and mess up your whole scheme. There's a good reason why the codes have evolved to protect people from themselves, and, what may be more important, those who you may sell your house to sometime in the future...they expect things to be done per the codes.
 

K9mlxj

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If a device is properly grounded, then yes, you could extend it to generate additional grounded devices, but I've been led to believe, the original ground MUST be in the same cable or conduit as the power leads and run back to the power panel...you're bus bar wouldn't cut it if I'm interpreting it properly.

In that case, I'll just add one 20A grounded circuit from the panel, which I'd use for any extension that I need for the rooms. I can then also use that ground from the new circuit and provide ground to the ground bus bars, where ground wires can be fed to convert all the old 2-prong outlets.

The issue is, when you have a single cable, if you need to do some work, you know that if you break the ground, it won't affect potentially numerous other devices that aren't obviously in the same chain. When you run a separate ground, then distribute it to who knows where, someone down the line could disconnect it and mess up your whole scheme. There's a good reason why the codes have evolved to protect people from themselves, and, what may be more important, those who you may sell your house to sometime in the future...they expect things to be done per the codes.

If the bus bars are grouped per each old circuit, then it's no different than running extensions for each circuit (except it's just the ground wire). Example: if anyone breaks the ground at a receptacle in a grounded circuit, all the outlets downstream of that same circuit will lose the ground as well.

So this would be the updated scheme:

Outlets from ungrounded circuit 1 (daisy chained) -> bus bar A
Outlets from ungrounded circuit 2 (daisy chained) -> bus bar B
...
bus bar A, bus bar B --> bus bar C

bus bar C -> New circuit ground

If the location of an outlet is somewhat close to a bus bar, I might just directly feed a ground wire straight from the bus bar to that outlet instead of from another converted outlet, so in the end it'd actually be done better than daisy chain per circuit.


All the bus bars will be located along one single joist so it's easy to trace.

I'd have one single continuous run of ground wire along the joist, where it'd go straight thru' all the bus bars that are fastened at different spots along that run on the side of the joist.

Needed new outlets from the rooms/living room would feed from the new 20A circuit, complying with code.


I can actually use the new circuit and put J-boxes where I can splice off the ground at multiple locations to feed ground to the old outlets, instead of using the bus bars, but I like the bus bars setup it's clear and organized, people can see how the ground wires are fed, and it's easy to feed an additional ground wire from a bus bar -- better than using wire nut. (I do need to feed the ground from the new circuit to the bus bars at one spot.)

I plan to add extensions to upgrade the kitchen wiring, and for those extensions I'd be add all new separate circuits as the kitchen appliances are all power hungry.

The crawl space provides an easily accessible area where I can drill small holes into locations of the existing outlets and feed the ground wires to. If it's a concrete slab I won't be able to do it easily like this.
 
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Jadnashua

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Again, while it may work, I don't think that it will pass code. Say you disconnect that new grounded cable for something...without knowing, all of the rest of the things that you thought (or more likely, the next owner) were grounded, no longer are without warning and they are likely on different circuits. Each circuit should be able to stand on its own.
 

jdz

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The ground wire for any circuit must be ran in the same raceway as the conductors that power the circuit. So, if you are using romex that doesn’t have a ground wire in it (hot and neutral or two hot), you cannot run a ground wire alongside it for grounding and still conform to the code. You would have to put all the wires in conduit but you cannot put romex in conduit so the only way to ground it and comply with code is to rewire with the proper wire.

You definitely cannot just run a bunch of ground wires to the copper piping and use the piping as the ground inside your house. Using the buss bar setup you are describing or the pipe ground setup you describe are asking to get someone killed. There is a reason why the NEC exists. It might take a little more work to do it right but at least you can sleep soundly at night.
 

Stuff

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NEC 250.130(C) is the section I quoted which allows separate grounding conductor.
 
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jdz

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I was looking at nec 300.3 (B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4).

For every rule in the nec, there is an exception. It sounded like the op just wanted to dangle ground wire down to the closest piece of pipe and call it a ground. That’s scary. With the effort he is going to go through, I would just put in a proper ground and start from there. It’s not difficult to do and the outcome will be much better.
 

WorthFlorida

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Grounding to copper or metal pipes not allowed as stated before. One reason is there is now so much cpvc or pvc plastic pipe being installed. Now throw in PEX. Many repairs, especially at the water heaters, old copper or galvanized pipes are cut out and replaced with non metallic piping.
 

Stuff

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I think it used to be legal to dangle the wires and go to the closest pipe. Now you can still dangle wires but they need to go to a real ground. The NEC hasn't really addressed those wires most likely as it is not done very often.

Yes, the ideal case is that you re-wire the house. And others have stated that if you are running a ground you might as well run a cable. Easier said than done, though.
 
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