250.52(A)(3) Concrete-Encased Electrode

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crossman said:
The 20 foot length required for a CEE can most certainly be, for example, two 10 foot pieces of rebar connected together with tie wire.

As a matter of fact, twenty 1 foot pieces of rebar in the bottom of the foundation, and tied together with either tie wire or by multiple connections to a GEC would be acceptable as a grounding electrode according to the literal text of the code.
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In fact 250.52(A)(3) does NOT!

It does say the electrode consists of at least 20'.
 
tryinghard said:
In fact 250.52(A)(3) does NOT!

It does say the electrode consists of at least 20'.
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But the last sentence of 250.52(A)(3) permits reinforcing bars to be bonded together using the usual steel tie wire. In y opinion that would permit you to bond together 2 10 pieces of rebar to make one 20 foot piece of rebar for the purposes of a grounding electrode.

Chris
 
tryinghard said:
In fact 250.52(A)(3) does NOT!

It does say the electrode consists of at least 20'.
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...at least 20 feet of one or more bare or zinc galvanized...

The way it is worded, two 10 foot pieces is definitely 20 feet of one or more rods.
 
I think the INTENT is a 20' rebar/#4 Cu.

I can't imagine that our AHJ would approve
20 x 1' peices Rebar wired together.
or
40 x 6 inch pieces of Rebar, wired together.

Not any more than 20 x 1' pieces of #4 Cu,
wired together!

LOL.
 
glene77is said:
I can't imagine that our AHJ would approve
20 x 1' peices Rebar wired together.
or
40 x 6 inch pieces of Rebar, wired together.
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Unless they have local amnedment they would have no choice but to accept it. The NEC does allow it.

Not any more than 20 x 1' pieces of #4 Cu,
wired together!
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That would be a violtion.
 
raider1 said:
But the last sentence of 250.52(A)(3) permits reinforcing bars to be bonded together using the usual steel tie wire. In y opinion that would permit you to bond together 2 10 pieces of rebar to make one 20 foot piece of rebar for the purposes of a grounding electrode.

Chris
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The last sentance does not state electrode, this is for bonding other steel
 
Just section from the 2008 ROPs

I can post the entire proposal which was for some text changes but I think just the panel statement by itself is pretty clear.


5-153 Log #3648 NEC-P05 Final Action: Reject
(250.52(A)(3))
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Panel Meeting Action: Reject

Panel Statement: The proposal would unnecessarily restrict the creation of a concrete-encased grounding electrode by not permitting the connecting together of two or more lengths of reinforcing steel to equal 20 ft or more in length.
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iwire said:
Just section from the 2008 ROPs

I can post the entire proposal which was for some text changes but I think just the panel statement by itself is pretty clear.
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This is clear, and 250.52(A)(3) can be read differantly in either sentence.

This is a mute poing with 20' of #4cu conductor as the electrode.
 
tryinghard said:
This is clear, and 250.52(A)(3) can be read differantly in either sentence.

Your the first person I can recall reading it as you do and honsetly I can not find a way to read it your way. :-?
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chris kennedy said:
How quickly we forget.
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Chris After going back and re-reading I have to ask.

In your post that you linked to, was that what you where trying to say. That the steel had to be at least one 20' section?

If so I totally misread it yesterday, I would not even considered you where saying that as the you posted the code section that says it can be more then one.

After seeing the CMP statement do you now agree that 20' of rebar could be 20 - 12" sections tied with tie wire?
 
It is possible that the length of a concrete footer would not equal 20' in one "straight" line. 20' of copper conductor can easily be bent around corners or even looped back and forth, but it will typically take multiple 1/2" rebar pieces to accomplish the same tasks.
 
iwire said:
In your post that you linked to, was that what you where trying to say. That the steel had to be at least one 20' section?
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Yes sir.

If so I totally misread it yesterday, I would not even considered you where saying that as the you posted the code section that says it can be more then one.

After seeing the CMP statement do you now agree that 20' of rebar could be 20 - 12" sections tied with tie wire?
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Yes sir, I agree, the pic I posted on this thread is poor, but you can see I hit the closest low bar as it was tied to a mile of steel. I have been reading 250.52(A)(3) incorrectly.
 
Well considering such a big deal is made by the NEC about the conductor to rebar connection being perfect it is a bit surprising that you could have tied rebar right on each side of that careful installed listed for the purpose connection.

It seems I should just as easily use bailing wire to tie a 4 AWG copper on to the rod. :confused:

That aside, I did think the sections wording was straight forward.
 
iwire said:
tryinghard said:
This is clear, and 250.52(A)(3) can be read differantly in either sentence.

Your the first person I can recall reading it as you do and honsetly I can not find a way to read it your way. :-?
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I may be and am glad for it, I am intentionally grasping at the fact that it "can" be understood differently. The reasoning by some that NEC allows an undermined amount of steel tied is bad! This can mean 20 1? steels can be tied in a complete bundle you see the way it?s tied is now debatable!

There are probably ten?s of thousands posts are written annually regarding CEE, these are critical and important. I will say most of these are posted to figure out how the steel will be installed yet this is not our trade. Worse yet I don?t want a non-electrician installing electrical
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