My Argument with Iwire

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iwire said:
It's all good :smile: ........ well no the CMPs comments are not good, I swear they whipped that one out with little to no thought at all. :rolleyes:

In my first post when I said I was lost I was talking about the CMP comment, it makes no sense at all.
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I was lost too until this thread progressed to the last few posts, now it all kinda makes sense.

Like I've said before about the Code, sometimes it's clear as mud. :grin:
 
iwire said:
It's all good :smile: ........ well no the CMPs comments are not good, I swear they whipped that one out with little to no thought at all. :rolleyes:

In my first post when I said I was lost I was talking about the CMP comment, it makes no sense at all.
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I argee - as mentioned it is a contradiction. Since there was at least a dozen or so proposals seeking to clarify the issue in one way or another - they sought to avoid this issue and further the contradictions in the code with their comments. (And no, I'm not upset that they did not accept mine - but responded to Mike Holts in this case with aforementioned fence sitting comment.)

For full context:

5-157 Log #3051 NEC-P05​
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Final Action: Reject
(250.52(A)(3))​

_______________________________________________________________​
Submitter:​
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Mike Holt, Leesburg, FL​

Recommendation:​
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Revise text as follows:
(3) Concrete-Encased Electrode. An electrode encased by at least 50 mm (2 in.)
of concrete, located horizontally near the bottom or vertically, and within that
portion of a concrete foundation or footing that is in direct contact with the
earth, consisting of at least 6.0 m (20 ft) of one or more bare or zinc galvanized
or other electrically conductive coated steel reinforcing bars or rods of not less
than 13 mm (? in.) in diameter, or consisting of at least 6.0 m (20 ft) of bare
copper conductor not smaller than 4 AWG. Reinforcing bars shall be permitted
to be bonded together by the usual steel tie wires or other effective means.
Exposed or concealed reinforcing bars that are bonded to reinforcing bars
meeting the criteria of this section shall be considered part of the electrode.
Where multiple concrete-encased electrodes are present at a building or
structure, it shall be permissible to bond only one into the grounding electrode
system.​

Substantiation:​
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There is a long standing debate as to whether or not a piece of
rebar (connected to the footing/foundation steel) that pierces the concrete and is
installed inside of a framed wall can be connected to and be used as a concrete
encased electrode. This proposal is intended to clarify this practice is a
permitted one.​

Panel Meeting Action: Reject
Panel Statement:​
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Only the portion of an electrode that is in contact with the
earth can be called an electrode. The exposed portion of the rebar could be
used as a connection point but cannot be considered as the electrode.​

Number Eligible to Vote: 16​
Ballot Results: Affirmative: 16
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OMG I remember this discussion..the opening proposal is a joke.. here we go again....sounds like a tune to me...:grin:

So you can not use steel rebar to connect to the ground as the clamps are not rated for the rebar. now you have to coat the reabar where it pretrudes from the rebar so it does not rot off due to chemical reaction. so now you damage the coating on the rebar and allow the chemical reaction to take place. just a couple of issues...

to late at night and 3 am comes ealy so no quotes or links just some basic knowledge and I am sure some one will post the UL, building codes and other info. So I hope they do not proceed down this course of wording as it is foolishness.

:grin: and I oot to know about foolishness :grin:
 
iwire said:
To me one of the great things about a CCC is that it could be 'permanent' if say a 4 AWG is run directly from the panel and all the way into the footing pour, the copper will not give out before the building does.
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How do you know the entire 20' is still there when the concrete is poured?
 
LarryFine said:
How do you know the entire 20' is still there when the concrete is poured?
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You don't - and frankly, who cares?!? That 20' is connected to another 20', and none of it is directly connected to the earth. While both concrete and steel are both conductors, the concrete is in connection with the earth, and only the steel counts???? Only part of it?!?
 
jwelectric said:
Where does it say that the five feet is part of the electrode? :confused:
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It does not, your right. And I realized my answer was bad but did not want to cheat and edit.:smile:

Working without my book here so bare with me.

It does not say the part outside the earth is an electrode it gives us specific permission to connect to it outside of the earth.
 
Like we were discussing last year....

If it is okay to connect to rebar which extends out of the slab, what is to stop me from running rebar above grade all the way to the service and bonding it to the service enclosure? Maybe with a little bitty short 4" piece of copper wire as the GEC?
 
crossman gary said:
Like we were discussing last year....

If it is okay to connect to rebar which extends out of the slab, what is to stop me from running rebar above grade all the way to the service and bonding it to the service enclosure? Maybe with a little bitty short 4" piece of copper wire as the GEC?
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That would be my point exactly.
 
And this is the point of the code making panel concerning the rebar.

Unless the metal water pipe, ground rod, rebar (through contact with concrete) is in contact with earth then it is nothing more than a connection point and not the electrode.

In my opinion the five feet of metal water pipe on the inside or the two feet of a 10 foot rod sticking out of the ground and including the rebar that is turned up out to the footing is nothing more that what is described in 250.64(F)(3) and is not the electrode itself. The electrode must be in contact with earth no matter how useless it might be.
 
crossman gary said:
Like we were discussing last year....

If it is okay to connect to rebar which extends out of the slab, what is to stop me from running rebar above grade all the way to the service and bonding it to the service enclosure? Maybe with a little bitty short 4" piece of copper wire as the GEC?
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As long as there is 20 feet of rebar in contact with earth through the footer what would be wrong with this installation?

Can one not do the same thing with building steel?
 
jwelectric said:
the two feet of a 10 foot rod sticking out of the ground and including the rebar that is turned up out to the footing is nothing more that what is described in 250.64(F)(3) and is not the electrode itself. The electrode must be in contact with earth no matter how useless it might be. [/SIZE][/FONT]
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I understand your point and agree that the CMP is making a reasonable adjustement to provide rules which are easily accomplished in the field.

But just for the sake of debate, what if I ran all my GECs from the various electrodes back to the rebar sticking out of the slab, and then ran a single GEC back to the service, in other words, I used the rebar as the connection point described in 250.64(F)(3) as you mention. I don't think that would be good.

Of course, 250.64(F)(3) mentions copper or aluminum, and gives a minimum size, but that is beside the point.
 
jwelectric said:
As long as there is 20 feet of rebar in contact with earth through the footer what would be wrong with this installation?

Can one not do the same thing with building steel?
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Well, yeah, you can do that with building steel.

Now, for the rebar, so I extend it 100 feet to the service using tie wire to connect the rebar pieces together? That just seems really inappropriate because that 100 feet is really a GEC.
 
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