What is NEC Code For This Grounding Scheme ?

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bud-- wrote:

I had talked to an electrician on the phone and he said something like "oh, those old panels just had a neutral bar and they put the grounds on there too. That is not good, especially for eletronic devices to be protected." He then went on to say he would install a ground busbar in panel.
This is what I am dealing with! If it wasn't for you guys, I would have had some pretty off the wall things done to my electric service. It seems like I am at a point where I know more than they do about this. This is truly backwards, but with all the help here, I will know when I find an electrician who knows what he is doing. Ususally, the response is "hire a professional", but in my case, it's "go to NG and THEN be informed enough to hire a professional (if one exists in my city).
Anyway, thanks to everyone who is participating in this thread. It is VERY helpful to me. -- John
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It certainly does no harm, except to your wallet, for him to install a ground busbar in the service panel -- but it does no good either: since Code requires ground and neutral to be bonded together in the service panel, electrically they're all one bar anyway.
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Doug Miller (alphageek at milmac dot com)
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wrote:

It is really based on the size of the service entrance cables 250.66, which is usually based on the service disconnect size but that varies between residential and commercial. Residential generally gets away with a smaller SE cable because of load diversity. The other rules refer to the particular electrode used. You never need more than a #6 to a ground rod/plate, #4 to a UFER. When you are stringing several electrodes togerther you need the minimum size for the best electrode down stream up to the 250.66 size. Water pipes always use the 250.66 size.
250.66 (short version) SE cable GEC size copper aluminum Cu Al Res service 2 or smaller 1/0 or smaller 8 6 typical 100a 1 or 1/0 2/0 or 3/0 6 4 typical 150a 2/0 or 3/0 4/0 or 250 4 2 typical 200a
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snipped-for-privacy@aol.com wrote:

Thanks for the chart, but I have to admit I have no idea what those abbreviations mean. :)
I asked the electrician today what size wire would go from ground rod to panel and he said #8 since it was a 100 amp. It sounds like you are saying it should be #6?
-- John
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wrote:

You never need to be bigger than 250.66 so if you have a typical 100a service #8 copper is OK. If you upgraded the service you would have to upgrade the GEC SE = Service Entrance Cable GEC = Ground Electrode Conductor (wire to the rod or water pipe) Cu = copper Al = Aluminum
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And... 2, 1, 1/0, 2/0, 3/0, 4/0, and 250 are wire sizes. "1/0" "2/0" etc are pronounced one-aught, two-aught, etc.
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Doug Miller (alphageek at milmac dot com)
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Minimum that was required was an earth ground rod near breaker box and connected direct to breaker box. Your description implies no proper earthing existed. A ground rod connected as close as possible to the breaker box is the only upgrade required and serves other useful purposes beyond what is addressed by code. Other utilities (cable and telephone) should connect to that same ground so that those utilities provide minimally sufficient electronics protection (as hallerb suggests elsewhere). That suggested to meet current code even though other marginal earthing is not required to be upgraded.
I no longer rememeber if this recommendation was posted. Other simplest corrections to consider for human safety were summarized by volts500 in alt.home.repair entitled "Grounding Rod Info" on 12 July 2003 at http://tinyurl.com/hkjq Those recommendations are so simple, so easy, so inexpensive, and so improve human safety issues as to also be performed - to upgrade basic safety grounding closer to what current code requires.
The only thing you do not have (according to your description) and that you must correct is earthing of AC electric. Those additions to safety grounding inside the house (from volts500) and the tying of all incoming utilities to a common ground are required by current code; not necessary for you to upgrade; but should be performed anyway because those little improvements provide significant human safety improvements for so little effort.
What size should a ground wire be? That varies based on things such as the amperage of electric service as summarized by gfretwell. Standard used in most all homes is 6 AWG. Ground wire is usually larger than what is required by code. 6 AWG copper is an industry default standard for residential electric.
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John Ross wrote:

John I'll get grief for this but I suggest you call the nearest office of the International Brotherhood of Electrical Workers (IBEW). Numerous people will now tell you that they will cost too much but that just isn't so. On average a unionized shop employs twelve electricians. The pricing of Electrical work is very competitive. The difference between a unionized shop and a non union shop is not what the customer pays but that more of what you pay goes to wages and benefits. Better pay attracts better electricians. A union inside wireman has four years of formal training. A union residential wireman has at least two years of formal training and four years of supervised field experience before they can work unsupervised. I am self employed but I was trained by the Joint Apprenticeship and Training Program of the National Electrical Contractors Association (NECA) and the IBEW. The Union local office will be happy to give you the names of three NECA member contractors that do residential work. You will then have a better chance of getting a quality job. No group of electricians is completely free of dunderheads but using a union shop will at least improve your odds. -- Tom Horne
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And now you've gone and gotten it wrong again. Metal water pipe is *required* to be used as a grounding electrode. You said it's not. That's not true.
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Doug Miller (alphageek at milmac dot com)
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False.
"All grounding electrodes as described in 250.52(A)(1) through (A)(6) that are present ... shall be bonded together to form the grounding electrode system. .. 250.52(A)(1) Metal underground water pipe."
If it's there, Code requires it to be used "to form the grounding electrode system" i.e. as an earth ground.

Wrong -- it MUST be a grounding electrode if it's present.

True -- but not relevant to the question of whether using it is optional or required. If it's present at all, its use as part of the grounding electrode system is MANDATORY.
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Doug Miller (alphageek at milmac dot com)
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Doug Miller wrote:

Doug, as it is now the only ground is to the water pipe, but back then they just connected it any convenient place near panel--not within 5 foot of pipe entrance. So if I have the ground rod installed AND leave the current situation, am I right in that it will still serve as a earth ground AND a bonding to the pipes. BTW, it is still all metal, so if not required, I would assume it is ok just to leave that as is. Does that satisfy what you said above?
-- John
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No, not unless the connection to the water pipe is within 5 feet of the entrance.

Ground rod, and connection to the metal water pipe within 5' of the point at which it enters the building.
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Doug Miller (alphageek at milmac dot com)
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On Sep 30, 11:15 am, snipped-for-privacy@milmac.com (Doug Miller) wrote:

Code demands that the AC electric have a proper connection to earth ground. Any one of the electrodes in paragraphs two through seven are sufficient. The electrode defined in paragraph one (water pipe) is not sufficient.
Assume that John Ross was correct - that ALL earthing electrodes must be connected. Then every steel I-beam concreted in earth must be bonded to the breaker box. Water well casing must be bonded to AC breaker box. All rebar inside concrete footing must be bonded. Rebar inside any concrete basement floor must be bonded. Any steel plate buried in earth must be bonded. Any "other local metal underground system or structure such as piping systems and underground tanks" (quoted from paragraph seven) must also be connected to breaker box. According to John, if any of those six items exist, then they also must be bonded to the breaker box.
Why are bonding wires not attached to every of six items? Because Doug Miller is wrong. The breaker box only needs one earthing electrode that conforms to paragraphs two through seven. Code says that any electrode used for earthing must be bonded together to form a single earth grounding system. Any of those other six electrodes not being used for earthing need not be connected to the breaker box - in direct contradiction to Doug Miller and the naive salesman Bud.
Code says that any electrode connected for earth must also be bonded to the breaker box. If used to earth the telephone line protector, then that electrode must also be bonded to AC electric box. If cable TV is earthed to any of those electrodes, then that electrode also must bond to breaker box. Any electrode used as earth ground must be bonded together. Listed are six earthing electrodes that would not be connected to breaker box because nothing was using them for earth ground. According to Doug Miller, all six of those electrodes also must be connected by 6 AWG wire.
If you want to bond the 'first five feet of water pipe' to breaker box, then by all means do so. But that is beyond what code would require of John Ross. What is most clearly required: a connection from breaker box to any other earthing electrode used to ground telephone, cable TV, satellite dish, TV antenna, etc. Those connection are required by code so that all 'being used electrodes' are bonded into one earthing system. Yes, the phone line and cable TV earthing electrodes also must earth the AC breaker box because those electrodes are being used to earth telephone and cable - as also required by code.
A metal underground tank is an earthing electrode according to paragraph seven. But if not being used by anything as an earth ground, then AC breaker box also need not be bonded to that underground tank ... in direct contradiction to what Doug Miller and naive salesman Bud have posted.
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Correction. This should have read "According to Doug Miller, if any of those six tiems exists, then ..."
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Correction: according to the National Electrical Code.
I even quoted the relevant portions of it.
Here, I'll do it again. Pay attention this time.
"All grounding electrodes as described in 250.52(A)(1) through (A)(6) that are present at each building or structure served SHALL BE bonded together to form the grounding electrode system." [2005 NEC, Article 250.50]
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Doug Miller (alphageek at milmac dot com)
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Doug - why is that underground tank not connected to breaker box? It completely meets paragraph seven as an' earthing electrode. Using your reasoning, then that underground tank must be connected to breaker box. But nothing is using the tank as an electrode. Therefore it does not exist - is not 'present' - as an earthing electrode. It exists only as a tank even though it 'could' become an earthing electrode according to code. Please learn what that paragraph really says.
If we drive a ground rod into earth and don't connect anything to it, then according to Doug Miller's interpretation, we must connect that rod to breaker box with a 6 AWG wire. Obviously not. It 'could' be an earthing electrode. But it is not because nothing else is using it for earthing. Therefore - and in direct contradiction to what Doug has posted - we need not connect it to the breaker box.
The phrase is "that is present". That underground tank and that isolated ground rod are not 'present' because nothing is using it as an earthing electrode.
If we earth an overhead TV antenna (as required by code), then that ground rod must also connects to the earthing system being used by AC breaker box. Why? That TV antenna ground rod is 'present'. It now exists as an earthing electrode and therefore must be interconnected to other earth grounds.
Code only requires John Ross to have one earthing electrode. Minimum to meet that requirement is one earth ground rod located and connected as short as practicable to breaker box. Being earthed by a wire as short as possible is also a code requirement. For other reasons, we want that wire to be 'less than 10 feet' and routed separated from other wires. That one earth ground then meets a minimum code requirement for earthing.
If John Ross is using some other earth ground for telephone or cable TV, then that earthing electrode is 'present' - must also connect to the breaker box. Code also says those other utilities must connect less than 20 feet to the earth ground. Just another reason why all incoming utilities should enter at a common service entrance - since all must use the same earthing 'system'.
Doug - please learn that what code paragraph says. You keep quoting it and do not understand what it is saying. Accroding to you, then every underground tank also must be connected by 6 AWG wire to the breaker box. Any steel plate buried in earth must be connected. Obviously that is not true. Your interpretation obviously is in error.
On Sep 30, 8:45 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

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Because the installer was listening to you, instead of reading the Code.

No, not using "my reasoning" -- using the plain language of the Code.

Then that's a Code violation.

You have a peculiar understanding of "present".

I'm perfectly well aware of what that paragraph says, but it appears that you are not. The Code says, simply, that if the items are present, then they must be bonded together to form the grounding electrode system.

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

What, you mean they're not there?
What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

Tom - please don't attempt to lecture me on what the Code says, when you clearly don't understand it yourself.

You keep *not* quoting it, and *not* understanding it.

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?

As I've already pointed out to you, this is not true.

What part of 250.50 "ALL ... that are present ... SHALL BE BONDED TOGETHER..." are you having such a hard time understanding?
--
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Doug Miller (alphageek at milmac dot com)
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snipped-for-privacy@milmac.com (Doug Miller) wrote:

Woops, my mistake -- I thought that was (A)(6) and required to be part of the system; actually, it's (A)(7). You did get this part right: underground tanks aren't required to be bonded into the grounding electrode system.
You got everything else wrong.

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Doug Miller (alphageek at milmac dot com)
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On Oct 1, 12:58 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

So those millions of fuel oil tanks buried outside homes to provide fuel for winter heat - all tanks are code violations? How curious that electrical inspectors did not see them as code violations. According to Doug Miller, all those fuel oil tanks are code violations because a 6 AWG wire does not connect them to the breaker box. Doug - you don't do this stuff, do you? You are assuming a layman's interpretation of the word 'present'. A tank that meets paragraph (A)(7) as an electrode also is not 'present' according to the code.
If word definitions were so obvious, then explain why a rope does not bond two items together. Code says two items must be bonded. They look bonded together to me. We cannot pull them apart. Therefore they must be bonded - by a rope. Clearly that meets code since the meaning of bonding is obvious to any layman. Or maybe words have context. Obvious is that millions of household oil tanks are not in code violation as you have just posted. Please learn the code before lecturing others.
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What part of "all ... that are present ... shall be bonded together" are you having trouble understanding?
This whole thing started with your idiotic statement that a metal underground water pipe was not required to be used as a grounding electrode, remember?
Now go *read* the Code, and STFU.
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Doug Miller (alphageek at milmac dot com)
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