What is NEC Code For This Grounding Scheme ?

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On Sep 27, 11:26 am, snipped-for-privacy@gannon.edu wrote:

Using water pipes as conductors is not acceptable. We bond both water pipes and gas pipes (some jurisdictions) for the same reason - to remove electricity from those pipes. A bond to the gas pipe would not be an earth ground since gas meters routinely have electric insulators. Some jurisdictions want the gas pipe bonded to breaker box safety ground; others do not. Consult the gas company for what they want.
As w_tom repeatedly notes, the reason for pulling a cable is because that cable is approved as a conductor. Pipe that was acceptable as a condutor more than 30 years ago is no longer approved as a conductor today.
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Folks:
"He who argues with a fool makes two"
For everybody's benefit but the silly goose's, the reason we must now supplement the water-pipe ground with a driven electrode is because the city might use plastic pipe or dielectric unions. An all-metal city water system, miles of metal pipe full of water buried in damp ground, is a very very very good ground, but we can't always depend on it staying that way.
G P
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http://esteroriverheights.com/electrical/ground.jpg
250.21 from the 2002 handbook
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On Sep 27, 12:34 pm, snipped-for-privacy@aol.com wrote:

Ahh, but that picture is not using pipes as a conductor. That 'less than five feet' is where the pipe is an earthing electrode according to code. Code defines a difference between an electrode and a conductor. To be an electrode, the connection to that pipe must be "less than 5 feet". If connecting the breaker box to earth via a cold water pipe anywhere inside the building, then those pipes are being used a conductors - not legal.
Some jurisdictions will reject your picture IF those ground connections are not together. Others may reject it altogether; want the ring ground (halo ground) or ground rod 6 AWG wire to be attached directly to the 6 AWG wire from breaker box with a split bolt or something that connects those wires together without the pipe.
All jurisdictions will reject that connection if the various grounds do not connect 5 feet from earth. If the pipe is being used as a conductor - if the pipe connected between those various clamps is many meters apart - then it is not legal. Since those wires bond adjacent to each other, then most jurisdictions will consider that pipe an electrode - not a conductor. From that picture: "Connection made within 5 ft of point of entrance of pipe." At that point, the pipe is considered an electrode - not a conductor.
Using pipes as a conductor to connect a ground rod to breaker box is not acceptable. In John Ross's situation, the breaker box was earthed to a pipe much more than 5 feet from where pipe contacts earth. Therefore the pipe (as an earthing connection) was being used as a conductor - no longer acceptable. That connection was sufficient for bonding pipes to the breaker box. But it is no longer acceptable as an earth ground. IOW from the perspective of code. John Ross had no earth ground until the electrician connected a ground rod to breaker box (again, a connection not made using his pipes).
For the pipe to be an electrode, code says that pipe connection must be less than five feet from earth. Electrode conductors can merge on one electrode. Connection to earth on pipes farther than 5 feet means the pipe is being used as a conductor. Yes, some jurisdictions may permit merging connections from various electrodes on one pipe too far from earth. Others may not if the pipe is not considered an electrode. But that picture clearly shows connection made adjacent where the pipe is a earthing electrode; is not a conductor.
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To perform electrical work, you are required to understand everything in Article 250.52. If using water pipe for earth ground, then any other electrode in Article 250.52(A) paragraphs two through seven also must be installed. Why? Water pipes are no longer sufficient for earthing. If using any other earthing electrode, then a water pipe earthing electrode is not required. BUT if using the water pipe for earthing, then the building remains insufficiently earthed according to Article 250.52. Another electrode must be installed.
"A metal underground water pipe shall be supplemented by an additional electrode .... " A building must also be earthed by structure frame, Ufer ground, ground ring (halo ground), or an earthing plate or rod. Water pipe is no longer sufficient for earthing. You are supposed to read everything; not read selectively. Keep reading. Article 205.52(D)(2). Article 250 then continues another 12 pages farther.
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False. If metal water pipe is present, it is *required* to use it as a grounding electrode in addition to the other electrodes.
--
Regards,
Doug Miller (alphageek at milmac dot com)
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On Sep 27, 11:36 am, snipped-for-privacy@milmac.com (Doug Miller) wrote:

It metal water pipe is present, it is *required* to be bonded. Interior metal water pipes must be bonded if the underground pipe is plastic or metal. Makes no difference whether the water pipe does or does not also do earthing. 1) it still must be bonded. 2) the water pipe earth ground is considered so inferior that some other earth ground electrode must be installed.
We must remove electricity (electrical faults) from pipes by bonding pipes to breaker box safety grounds. Some jurisdictions also want gas pipe bonded. All water pipes must be bonded so that electricity is not flowing in those pipes. Bonding is essential to human safety. Some jurisdictions so worry about electricity in the plumbing as to require a dedciated bond to steel bathtubs. Are we earthing the bathtub? No. We are bonding it so that electric fault currents will trip a circuit breaker. That also has nothing to do with earthing.
When the water pipe is bonded 'less than 5 feet' from earth, then it also acts as an earth ground. But code says the building is still not properly earthed. The building is not earthed until some other earthing electrode is installed. Code still says that water pipe is an earthing electrode (paragraph one). Code also says that water pipe earthing electrode is not sufficient. Some other earthing (from paragraphs two through seven) must be installed so that the building is sufficiently earthed.
That cold water pipe must be bonded even if the water pipe makes no earthing connection. Why? We connect to pipes to remove electricity - for human safety.
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Isn't that what I just said?
Restoring the part that you just snipped, you wrote: " If using any other earthing electrode, then a water pipe earthing electrode is not required. "
That's what I said is false. And it is. You got it right the second time around.
--
Regards,
Doug Miller (alphageek at milmac dot com)
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On Sep 27, 12:40 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

"If using any other earthing electrode" is not even a valid "IF" here. Replace "If using" with "Required is using" any other earthing electrode. Does not matter whether the water pipe is or is not an earthing electrode to breaker box. The error was that the state of the water pipe (if or if not an electrode) is completely irrelevant. The code now says some other earthing electrode from paragraphs two through seven MUST be installed. Yes exceptions exist. But those exceptions do not apply here. John had no earthing electrode. What John considered an earth ground was not connected 'less than 5 feet' from earth; therefore was not an earthing electrode. He must install one that meets current codes. That is what one electrician would have done if connecting a earth ground rod directly to breaker box - no other changes.
Relevant in John Ross's situation: John had no earthing electrode. His breaker box was earthed by using pipes as a conductor. John has no choice. His breaker box needs an earthing electrode that connects to breaker box via 6 AWG wire; not connected via pipes.
Connecting a ground rod to his pipe where pipe is an electrode still would not meet code. Both pipe and ground rod electrode would still be using pipes as a conductor. Not acceptable. He must connect a new earth ground rod to breaker box only via approved conductors such as 6 AWG bare copper wire.
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w_tom wrote:

Only for new installations. Adding ground wires for receptacles is not likely to trigger installation of a supplemental electrode.

John has a water service pipe electrode.

What John has was code compliant when it was installed. There is no requirement to change the connection unless he changes the service.

Bullcrap. He also doesnt have to bring his whole house up to the current electrical code.
Your stupidity is breathtaking.
--
bud--

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bud-- wrote:

Even though I probably don't *have* to to it, I assume adding the ground rod would be a good idea since the added cost is minimal--I assume you agree? One thing on that aspect: this area generally has hardpan soil condition. Is that good or bad news?
But as far as these wire sizes everyone is throwing around: is that required or suggested? I hear this size 6 mentioned. Is that the code from the rod to the panel or is that just suggested. Also, does that change with the size of the service (this is 100 amp)? I think this latest electrician said something about size 10 or 8.
And, if it is bonded correctly to the first five feet of pipe, what size of wire is require for that (that would be around a 30 foot run)?
I never would have imagined trying to ground a receptacle would turn into such an ordeal! And, like I said, not one of these electricians know what I am talking about when I qquote the NEC codes you guys mention. Scary...Had I not asked in here, I would have gone with that one guy who had the isolated ground rod that made no sense now that it was explained to me here.
BTW, I thought I was clever and called the electrical supply places for a recommendation for an electrician. They were of no help. Can anyone think of another source that would know a good electrician?
-- John
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wrote:

They probably didn't want to risk the loss of future business from all possible electricians by appearing to endorse one over the others.
I get all my best contractor references from friends and colleagues; works every time. Ask around. Or tell us your location, and someone here might be able to recommend someone local to you.
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John Ross wrote:

Connecting ground rods minimum #6.
Services - depends on service conductors. Generally 100A #6 is minimum used (can be #8 but the requirements on installation are very restrictive). 200A service #4 #4 may be used instead of #6 because #6 also has some limitations on use without 'protection'.

It should be noted that comments are based on the National Electrical Code. The NEC has authority only as adopted by entities that have control over electrical installations - states, cities, ... The NEC is the basis for the local code everywhere I know of, but can (and is) modified by many jurisdictions. The inspector can also allow variances. In your case, the jurisdiction or inspector allows connecting the added receptacle ground wires anywhere on the water pipe while the NEC now allows that connection only to the first 5 ft of the water pipe. [If the wire from electric service to water pipe electrode is not in the first 5 ft, as was permitted in the past, it does not make sense to connect added ground wires in the first 5 ft. And the added ground wires can usually be more conveniently connected elsewhere in the electrode system.]
The NEC chapter on grounding is probably the most confusing of the commonly used chapters.
--
bud--


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bud-- wrote:

<snip>
I spoke with the electrician today and he said he would use #8 wire (he said that was for 100 amp panel). Not sure what you meant by "very restrictive" in using that, I doubt he would do anything different.
Also, I am not so sure anymore that my city does allow the water pipe connection for add on grounds. In any event, did I understand you correctly that since the original "bonding" to the pipe was not required to be 5 foot from entrance, and since it is still all metal, it doesn't make sense to redo it to within 5 feet (if not required) i.e. just leave that alone until plastic pipe enters the picture?
I hope this doesn't open up a new can of worms, but I remembered that the way they did these houses, they didn't have a ground bar in the panel--the grounds are connected to the neutral bar. I asked him about that and he said he would just connect the new ground connections to the neutral bar also and "that was legal." Do you see a problem with that?
-- John
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John Ross wrote:

2005 NEC 250.64-B "Securing and protection against physical damage" "Grounding electrode conductors smaller than 6AWG [#8} shall be in rigid metal conduit, intermediate metal conduit, rigid nonmetallic conduit, electrical metalic tubing, or cable armor." All of them are a form of pipe (some are light weight pipe) except cable armor which is a spiral metal protection like BX. If the conductor is run through ferrous tubing/pipe there are additional requirements that directly or indirectly bond both ends of the pipe to the grounding conductor. If you use one of the required protection methods #6 should be cheaper.
"A 6AWG grounding electrode conductor that is free from exposure to physical damage shall be permitted to be run along the surface of the building construction without metal covering or protection where it is securely fastened to the construction; other wise it shall" use one of the protective methods above.
"A 4AWG or larger copper or aluminum grounding electrode conductor shall be protected where exposed to physical damage."

My intent was if the electrode connection to the water pipe is not within 5 ft of the building entrance, the restriction of connecting your added receptacle ground wires within 5 ft of the entrance does not make sense. I would usually split bolt the receptacle ground wires to one of the heavy grounding electrode wires anyway.
If the electrode connection to the water pipe is not withing 5 ft of the entrance it is safe as a grounding electrode as long as the metal water pipe is intact. Your call whether you move the connection.
[Note that when w_ talks about "bonding" the water pipe, it is not for using it as a grounding electrode, but is the connection required if the water service is plastic.]

At the service panel only (not downstream subpanels) the neutral and ground are connected. The neutral bar is usually insulated from the enclosure, but they should [almost] always be connected together at the service panel. The connection is often by a screw that goes through the neutral bar and screws into the enclosure behind - not at all obvious.
The neutral-ground connection at the service is part of providing a low resistance metal path for short circuit currents to trip breakers. The path is ground wire to neutral-ground bond to service neutral to transformer.
--
bud--

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bud-- wrote:

>> John Ross wrote:

It will need protection where it is located. The cable armor sounds the easiest (to bend), does that contain ferrous? <snip>

If it HAS to be moved, did you or someone say it has to be one contiuous wire all the way back to panel? I'm not sure how he could do that without wall damage. Can it be clamped to the point where it currently is at pipe and then jumpered to within 5 feet of entrance?

This panel (there is only one at house) has NO ground bar--grounds and neutrals are on the "neutral" bar. So he is proposing just adding these new ground connections there as well. Is that OK? If they are bonded together anyway, I can't see how it could hurt, but as you know this is all new to me.
-- John
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John Ross wrote:

Never used it.

That is standard in service panels.
--
bud--


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bud-- wrote:

Are you saying it's standard to bond together in service panel or it's common to just have the "neutral" bar and put grounds and neutrals on it? I was thinking that they may have just made them like this all those years ago, but now have the two bars in newer ones. But it's good to know at least ONE thing seems to be clear cut that it is OK to do. I was worried that would be a whole new can of worms.
thanks -- John
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John Ross wrote:

Bonding together is required. It is almost always done in the service panel.

Just a neutral bar also used for grounds is common.
--
bud--

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To clarify -- the reason this is acceptable in a service panel is that Code requires the ground and neutral to be bonded together at/in the service panel, so it doesn't matter whether two bars are used, or one -- electrically, it's all one continuous piece anyway. Subpanels require separate bars *not* bonded together.
--
Regards,
Doug Miller (alphageek at milmac dot com)
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