Ground Rod size

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It seems to me that the key point is not whether you can bond the GES to non-qualifying electrodes, but whether you can bond between qualifying electrodes via a non-qualifying electrode.

250.50 Grounding Electrode System. All grounding electrodes
as described in 250.52(A)(1) through (A)(7) that are
present at each building or structure served shall be bonded
together to form the grounding electrode system.
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250.53(C) Bonding Jumper. The bonding jumper(s) used to connect
the grounding electrodes together to form the grounding
electrode system shall be installed in accordance with
250.64(A), (B), and (E), shall be sized in accordance with
250.66, and shall be connected in the manner specified in
250.70.
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250.54(A) just restricts the use of AL conductors.
250.54(B) is about physical protection.
250.54(E) is about ferrous metal enclosures containing a GEC.

It is not clear to me that a bonding jumper between two qualifying electrodes that passes thru a non-qualifying electrode is prohibited. Maybe it is somewhere else but I am not finding it. I think there is a requirement that GEC be continuous (more or less) but I don't recall there is a similar requirement for bonding jumpers.
 
Can some one tell me, If I were to go to building steel (found one 20 feet away with cold water pipe ground conductor bonded to the beam) away from CATV box, would it be the same bare conductor that they have run to the ground rod? would I just go up the side of the building and attach it with some hangers? 20 feet would get me to where I would be in the five foot range of entering the building.How does it get fastened to the beam?
 
wireday said:
Can some one tell me, If I were to go to building steel (found one 20 feet away with cold water pipe ground conductor bonded to the beam) away from CATV box, would it be the same bare conductor that they have run to the ground rod? would I just go up the side of the building and attach it with some hangers? 20 feet would get me to where I would be in the five foot range of entering the building.How does it get fastened to the beam?
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I would just attach it with a listed lug. Drill the steel and bolt lug in place.
 
petersonra said:
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It is not clear to me that a bonding jumper between two qualifying electrodes that passes thru a non-qualifying electrode is prohibited. Maybe it is somewhere else but I am not finding it. I think there is a requirement that GEC be continuous (more or less) but I don't recall there is a similar requirement for bonding jumpers.
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Code does not differentiate between a GES bonding jumper, an EGS bonding jumper, or a superfluous bonding jumper... but you should. :D
 
In regards to structural steel are they all considered to be bonded to the GES ? The one I located has a good sized water pipe jumper attached to it then it heads off to the panel.I guess the jumper would make a good connection to the GES.Is it code that they go around cadwelding everything then pour the slab.
 
wireday said:
In regards to structural steel are they all considered to be bonded to the GES ? The one I located has a good sized water pipe jumper attached to it then it heads off to the panel.I guess the jumper would make a good connection to the GES.Is it code that they go around cadwelding everything then pour the slab.
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Structural metal may qualify as a grounding electrode [250.52(A)(2)], but where it does not, it is required to be bonded [250.104(C)]. Nowadays, some debate it because of the phrase "likely to be energized". In my experience it has always been at the very least, bonded. Cadwelding is not a required method of connection, but it is commonplace. Nonetheless, it seems rather obvious in your situation that the structural frame is at least bonded. As noted earlier, you can use structural metal as a GEC. When doing so, always ask if the provisions of 250.4 are met.
 
Is it allowed to bond the CATV to the water pipe ground wire ? it go's back to our sub panel.Also this ground wire from the CATV box if I understand correctly has to stay outside and can only travel 5 feet once it comes inside.
 
wireday said:
see previous postings
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wireday said:
yes outside
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A GES isn't necessarily inside or outside. But when outside, it is mostly below grade and can only consist of a few elements: rods, pipes, plates, and/or "ground ring" wire... and the GEC(s) or GE bonding jumpers. It can be somewhat extensive on industrial sites and generally referred to as the grounding grid, though it may not be arranged in grid fashion. Just called that because it has similarities to that of a substation and more extensive than required by the NEC.
 
wireday said:
Is it allowed to bond the CATV to the water pipe ground wire ? it go's back to our sub panel.Also this ground wire from the CATV box if I understand correctly has to stay outside and can only travel 5 feet once it comes inside.
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Yes, but to the water pipe itself within 5' of the water pipe entrance is preferred. See 800.100(B).

The grounding conductor from CATV box to GES tie-in point can be as long as necessary and is not limited to any certain distance inside. In residential, the bonding conductor is limited to 20FT. The exception permits a local electrode, but then you have to run a GEC as short as possible but as long as necessary.
 
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If I understand you, I can run bare #10 copper from CATV box into building, over the top of suspended ceilings and metal studs etc.If thats the case I could run it into our electrical room,plenty to tie into there.Is that correct? is in the code anywhere?
 
wireday said:
If I understand you, I can run bare #10 copper from CATV box into building, over the top of suspended ceilings and metal studs etc.If thats the case I could run it into our electrical room,plenty to tie into there.Is that correct? is in the code anywhere?
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Yes. But the general concept is to use the shortest possible route to the GES (or bring the GES closer as I mentioned about the exception for residential).
 
wireday said:
Is it allowed to bond the CATV to the water pipe ground wire ? it go's back to our sub panel.Also this ground wire from the CATV box if I understand correctly has to stay outside and can only travel 5 feet once it comes inside.
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only first 5 feet after entering a building of metal water pipe is considered part of the electrode. The GEC to the electrode must therefore land somewhere on that first five feet. Bonding jumpers can attach to the GEC or to the electrode, but any metal water pipe beyond 5 feet of entry isn't a GEC or an electrode.
 
Thank you Kwired, I would be bonding to the GEC or a steel beam further away than 5 feet,but at that point its the GEC or steel. Im happy to find out I can run the bare copper inside the building. And doing away with the ground rod at the box.
 
Question on bonding to structural steel, Is it ok to use the thinner wall girder, the ones that the siding gets screwed to ?Also are the bolts that attach them to the major trusses Ok or should we bond at that steel junction as well.
 
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