Is this compliant? GEC question

[jwelectric]

The requirement for connecting grounding electrode and bonding conductors is outlined in 250.68.
There were a couple of changes made in the ?08 cycle but nothing major. In the ?11 cycle a new subsection (C) was added with a change in the verbiage of how an electrode was to be bonded. I think that the confusion is in this new language.

I will hold my vote until I have a chance to better study this change.

 

[eprice]

I voted no, based on an application of Charlie's rules to 250.66(B). Is the #4 conductor to the CEE the sole connection to the CEE? No, there is a #6 connected to it as well. Therefore, 250.66(B) does not apply to that #4 conductor.

 

[roger]

I voted no, based on an application of Charlie's rules to 250.66(B). Is the #4 conductor to the CEE the sole connection to the CEE? No, there is a #6 connected to it as well. Therefore, 250.66(B) does not apply to that #4 conductor.

There is only one connection from the GEC to the CEE and this is a "jumper" then there is another "jumper" to the rod, neither the #4 nor the #6 are by definition GEC's, so in the OP's scenario and looking at the words " Where the grounding electrode conductor is connected to a concrete-encased electrode" there is still only one connection from the GEC to the CEE



Roger

 

[Dennis Alwon]

If installed as described in the OP how is the #4 the sole connection to the CEE when it also has a rod connected to it?

With that thinking how is it legal to jump between two ground rods and only use #6 to the first rod. The section on rods states when it is the sole connection then a #6 is okay. Now you add a bonding jumper then the first rod would be based on 250.66 and #6 would not be good to the first rod.

Here is what I think, I think as the wording is in the code the the install is not compliant as stated in my OP. What I think the intent is when the other electrodes demand a larger electrode, then the#4 would not be sufficient.

For instance if I went with a #4 to the CEE from the panel and then a 1/0 to the water pipe-- obviously that would be no good and I think that is the intent of the section but I am not sure.

What I don't understand is why we mostly agree than #6 from panel to first rod is okay even when we jump to the next rod with #6. Why is this okay and not my proposed installed.

Understand that I have never done this as I always run separate GEC except when I go to the rods. That is the only time I ever used a bonding jumper.

 

[eprice]

There is only one connection from the GEC to the CEE and this is a "jumper" then there is another "jumper" to the rod, neither the #4 nor the #6 are by definition GEC's, so in the OP's scenario and looking at the words " Where the grounding electrode conductor is connected to a concrete-encased electrode" there is still only one connection from the GEC to the CEE



Roger

True, in the scenario that is the basis of this poll, neither the #4 nor the #6 are the GEC. They are both bonding jumpers. But, 250.53(C) directs us to 250.66 for the purpose of sizing the bonding jumpers. 250.66(B) is talking about the sizing of a GEC (or in this case a bonding jumper) which for the purpose of my response, is the #4 conductor to the CEE. For 250.66(B) to apply, the conductor in question must be the sole connection to the electrode. In the scenario presented it is not. There is a #6 conductor connected to the CEE as well. 250.66(B) does not say "...that is the sole GEC connection to the grounding electrode"

 

[Dennis Alwon]

True, in the scenario that is the basis of this poll, neither the #4 nor the #6 are the GEC. They are both bonding jumpers. But, 250.53(C) directs us to 250.66 for the purpose of sizing the bonding jumpers. 250.66(B) is talking about the sizing of a GEC (or in this case a bonding jumper) which for the purpose of my response, is the #4 conductor to the CEE. For 250.66(B) to apply, the conductor in question must be the sole connection to the electrode. In the scenario presented it is not. There is a #6 conductor connected to the CEE as well. 250.66(B) does not say "...that is the sole GEC connection to the grounding electrode"

Again, why is the #6 to the rod okay since it says the sole connection to the electrode (singular).

As Roger pointed out the CEE is not connected to the gec it is connected to the water pipe.

If the CEE is only capable of handling a #4 why make it connect to the water pipe with a 1/0. Makes no sense.

 

[eprice]

With that thinking how is it legal to jump between two ground rods and only use #6 to the first rod. The section on rods states when it is the sole connection then a #6 is okay. Now you add a bonding jumper then the first rod would be based on 250.66 and #6 would not be good to the first rod.

Here is what I think, I think as the wording is in the code the the install is not compliant as stated in my OP. What I think the intent is when the other electrodes demand a larger electrode, then the#4 would not be sufficient.

For instance if I went with a #4 to the CEE from the panel and then a 1/0 to the water pipe-- obviously that would be no good and I think that is the intent of the section but I am not sure.

What I don't understand is why we mostly agree than #6 from panel to first rod is okay even when we jump to the next rod with #6. Why is this okay and not my proposed installed.

Understand that I have never done this as I always run separate GEC except when I go to the rods. That is the only time I ever used a bonding jumper.

I agree with what you are saying here. I don't think the wording of the code accurately expresses what we all think would be the desired intent of the code. My first response to this thread was based on what I think the code actually says, not what I think the intent was. Based on a strict reading of the code, I think that running a #6 to the first of two rods might be non-compliant, but I'm not about to start calling it that way And, If I were called to inspect the scenario you described in your OP, I think I would be inclined to not flag it. I would hope they would follow iwire's approach, and leave the rod in the truck.

But let me throw this into the discussion. What if someone (for whatever reason) installed say 15 rods in series. Could this electrode system approach the effectiveness of one water line electrode? I think it might. Would we still be comfortable with running a #6 GEC to that first rod? In that case a strict reading of the code might make more sense.

I guess if we were to try to write the code to cover all possible scenarios, it would be twice as thick and still not accomplish our objective.

 

[Dennis Alwon]

I would hope they would follow iwire's approach, and leave the rod in the truck.

Why would the ground rod make a difference? That is the point. The way it is being argued I would think that a 1/0 would still be needed without the rod in the scenario but not IMO.

But let me throw this into the discussion. What if someone (for whatever reason) installed say 15 rods in series. Could this electrode system approach the effectiveness of one water line electrode? I think it might. Would we still be comfortable with running a #6 GEC to that first rod? In that case a strict reading of the code might make more sense.

Again why does 15 rods apply but not 1 extra rod. At what point are we saying no to the install-- after 2, 3, 10, or 15 rods????

 

[eprice]

If the CEE is only capable of handling a #4 why make it connect to the water pipe with a 1/0. Makes no sense.

I agree with what you say here, but your poll question was whether or not it was code compliant, not whether or not it made sense. If you had reversed the order of the CEE and the rod in your scenario, I think we would all agree that the conductor from the pipe to the rod needs to be larger than #6, because downstream of the rod, there would be a CEE. I think most of us would say that the jumper from the water pipe to the rod, and from the rod to the CEE should both be #4 since the "best" electrode in that series is the CEE, but there is nothing in 250.66(A) and/or (B) that clearly takes us to that conclusion. In applying 250.66(A) to the jumper between the pipe and the rod we would have two choices:

a) Say 250.66(A) applies, because the rod is not connected to the GEC, it is connected to the water pipe. In this case a #6 would be adequate, or

b) Say 250.66(A) does not apply, because the jumper from the water pipe to the rod is not the sole connection to the rod. In this case a 1/0 would be required.

Edit: sorry, see the bold words. I meant to say pipe, not CEE

 

[eprice]

Why would the ground rod make a difference? That is the point. The way it is being argued I would think that a 1/0 would still be needed without the rod in the scenario but not IMO.

The rod makes a difference because of the way the code is written. Remove the rod from the scenario and then the jumper between the pipe and the CEE is the sole connection to the CEE and 250.66(B) clearly applies.

The scenario you presented is a case where "what the code says", and "what makes sense" are not necesarily the same.

 

[roger]

Not that this has anything to do with the code wording disscussion but, what the heck. Thinking about the dispersion of the lightning or a surge from the main bonding jumper outwards down the GES. The largest (strongest) link in the chain should take care of the bulk of it, now if the system progresively gets smaller why would any of the smaller pieces and their connections need to be sized per the strongest link?



Roger

 

[M. D.]

Submitter: Mike Holt, Mike Holt Enterprises

Comment on Proposal No: 5-212

Recommendation: Reject this proposal.

Substantiation: While this proposal does seem to address a real world
concern, it also creates as many concerns as it solves. For example, with this
new rule, no longer can an installer use the concrete encased electrode (CEE)
as a GEC. It is quite common to connect from the service equipment to the
CEE, then from the CEE to the underground water pipe. This is a very common
practice, especially in wood framed structures.
This change also eliminates
connecting the GEC to a ground rod, then connecting a bonding jumper from
the rod to another rod, as this proposed text states that only the water pipe or
structural metal can have bonding jumpers.

Perhaps instead of rejecting the proposal, the CMP could include a “where
used, bonding jumpers to water pipes or structural metal shall comply with
the following…” type of statement. As currently accepted, however, room for
confusion certainly exists.

Panel Meeting Action: Reject

Panel Statement: See panel action and statement on Comment 5-131. The
panel action on Comment 5-131 resolved the issues with the submitter. Section
250.64(F) provides other locations for grounding electrode conductor and
bonding jumper terminations. Section 250.50 requires all electrodes present to
be bonded together.

Number Eligible to Vote: 16
Ballot Results: Affirmative: 16

from 5-131

Panel Meeting Action: Accept in Principle
Revise 250.68(C) in ROP draft to read as follows:
“(C) Metallic Water Pipe and Structural Metal. Grounding electrode
conductors and bonding jumpers shall be permitted to be connected at the
following locations and be used to extend the connection to an electrode(s):
(1) Interior metal water piping located not more than 1.52 m (5 ft) from the
point of entrance to the building shall be permitted to be used as a conductor to
interconnect electrodes that are part of the grounding electrode system.
Exception: In industrial, commercial, and institutional buildings or structures
if conditions of maintenance and supervision ensure that only qualified persons
service the installation, interior metal water piping located more than 1.52 m
(5 ft) from the point of entrance to the building shall be permitted as a bonding
conductor to interconnect electrodes that are part of the grounding electrode
system, or as a grounding electrode conductor, provided that the entire length,
other than short sections passing perpendicularly through walls, floors, or
ceilings, of the interior metal water pipe that is being used for the conductor is
exposed.
(2) The structural metal frame of a building that is directly connected to a
grounding electrode as specified in 250.52(A)(2) or 250.68(C)(2)(a), (b) or (c)
shall be permitted as a bonding conductor to interconnect electrodes that are
part of the grounding electrode system, or as a grounding electrode conductor.
a. By connecting the structural metal frame to the reinforcing bars of a
concrete-encased electrode as provided in 250.52(A)(3) or ground ring as
provided in 250.52(A)(4)
b. By bonding the structural metal frame to one or more of the grounding
electrodes as defined in 250.52(A)(5) or (A)(7) that comply with 250.53(A)(2)
c. By other approved means of establishing a connection to earth”

Revise recommended text for 250.64(C) from this comment to read as
follows:

“250.64(C) Continuous. Except as provided in 250.30(A)(5), (A)(6),
250.30(B)(1) and 250.68(C), grounding electrode conductor(s) shall be
installed in one continuous length without a splice or joint. If necessary, splices
or connections shall be made as permitted in (1) through (4):
(1) Splicing of the wire-type grounding electrode conductor shall be
permitted only by irreversible compression-type connectors listed as grounding
and bonding equipment or by the exothermic welding process.
(2) Sections of busbars shall be permitted to be connected together to form a
grounding electrode conductor.
(3) Bolted, riveted, or welded connections of structural metal frames of
buildings or structures.
(4) Threaded, welded, brazed, soldered or bolted-flange connections of metal
water piping.”

Panel Statement: The revised text for 250.68(C) incorporates Comments
5-130 and 5-131 with editorial revisions made for clarity. The recommended
text for 250.64(C) was accepted with changing the term “required” to
necessary”.

Number Eligible to Vote: 16
Ballot Results: Affirmative: 16

 

[M. D.]

It does not look like they got all of Mike Holt's concerns Looks like the CEE can not be treated like the building steel or water pipe ..

 

[jwelectric]

I think that the confusion comes from changes in the 2011 cycle and how the question was asked both times. Dennis knows what this statement means.

I think that we all agree that the rod should not have entered the picture as the CEE is all that is needed to supplement the water pipe.

I think what was being addressed was the new wording that will only allow the supplemental electrode to land in those places outlined in 250.53(D)(2)
Notice that in 250.53(A)(2) That a rod that is supplemented the bonding conductor must land on one of five places.
It is my understanding that I wouldn?t be allowed to take each of two rods back to the CEE. It is also my understanding that if this rod was installed to supplement the water pipe it wouldn?t be allowed to hit the CEE.

I do see a need for a proposal to clear up information found in 250.64(F) and 250.53(C) and these new changes as these code sections seem to contradict each other.

 

[Dennis Alwon]

So here is what the code panel members either agreed on or didn't refute. Keith Lofland and Jeff Sargeant were the main members involved in this discussion.

The installation is not complaint, according to these guys, because of the sole connection concept. If a 1/0 were run to the CEE from the water pipe then it would be compliant even with the #6 to the rod. They never seemed to answer my question about why the two rods would comply with a #6.

In all they agreed with Roger and I, in concept, but they could not find the wording to support the install. They suggested a proposal.

Mike Whitt what say you-- you want to handle this one????? I am not sure I have the smarts for this one. :grin:

Keith laughed and said he is looking forward to reading this one. I guess he thought it would be hard to word correctly.