Continious service ground?

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George Stolz

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Windsor, CO NEC: 2017
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stew said:
Am I overthinkig this ? how about 250.64 (c)? continous and without splice? I always thought that the gec had to be continous no?
A GEC has to be continuous between the neutral connection at the service to the grounding electrode. Beyond that, the conductors that connect grounding electrodes together are "bonding jumpers" which must be installed according to 250.53(C).

250.53(C) requires the bonding jumpers to comply with 250.64 (A), (B), and (E).

250.64(F) allows us to run to a convenient grounding electrode, or each electrode individually.

250.64(C)(3) allows us to substitute a busbar for the first grounding electrode, and install bonding jumpers from that point.
 

stew

Senior Member
most inspectors here will tag you if you use a separate piece from the first rod to the second. even if you have 4 from the panel to the first rod and you then use another clamp and a short jumper. have seen this tagged many times. I use 6 anyhow and if i need to extend I use a ground crimp. elimininates the hassel.If I have an exisiting sytem I use this method to save copper. I guess I dont understand why when you use a # 6 from the panel that you are then required to size all jumpers at 4. (assuming a 200 amp service)
 

infinity

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stew said:
most inspectors here will tag you if you use a separate piece from the first rod to the second. even if you have 4 from the panel to the first rod and you then use another clamp and a short jumper. have seen this tagged many times. I use 6 anyhow and if i need to extend I use a ground crimp. elimininates the hassel.If I have an exisiting sytem I use this method to save copper. I guess I dont understand why when you use a # 6 from the panel that you are then required to size all jumpers at 4. (assuming a 200 amp service)


If you only have rods, #6 is all that is required regardless of the size of the service.
 

stew

Senior Member
doesnt the second connection ,the jumper to the second rod have to be #4? If it is spliced to be continous then 6 is ok but when it is a jumper from a second connector it then as I understand it becomes a bonding jumper which is required to be 4 correct? I understand the code to require all bonding jumpers to sized according to 250.66.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
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Electrical Contractor
stew said:
doesnt the second connection ,the jumper to the second rod have to be #4? If it is spliced to be continous then 6 is ok but when it is a jumper from a second connector it then as I understand it becomes a bonding jumper which is required to be 4 correct? I understand the code to require all bonding jumpers to sized according to 250.66.

Not those that connect only driven-rod electrodes, especially the second one. Why would one rod require more conductor than two?
 

George Stolz

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Windsor, CO NEC: 2017
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stew said:
I understand the code to require all bonding jumpers to sized according to 250.66.
Yes, 250.53(C) requires the jumpers to be sized to 250.66. Notice it doesn't say Table 250.66, just 250.66.
250.66 Size of Alternating-Current Grounding Electrode Conductor. The size of the grounding electrode conductor of a grounded or ungrounded ac system shall not be less than given in Table 250.66, except as permitted in 250.66(A) through (C).
250.66(A) says, no larger than #6 required. :)

stew said:
most inspectors here will tag you if you use a separate piece from the first rod to the second.
Well, now you have diagrams and narrative to show them, and see what they think. :)
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
stew said:
most inspectors here will tag you if you use a separate piece from the first rod to the second.

I do it because it saves on one-wire-only rod clamps; I have, however, bent the #6 in a U in a single clamp, which for some strange reason isn't a problem.
 

George Stolz

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Windsor, CO NEC: 2017
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The way I usually do it is with a continuous #6, entering from the top on the first one, and digging a shallow trench with my hammer to the second one, which dives upward. A sidewalk was poured over the rods later, so there was no worry of landscapers jacking up the wire. :)

Around here, it's assumed that one rod is less than 25 ohms, so I only drive two if they're the only electrodes present. (To be honest.)
 

stew

Senior Member
the interesting thing about the graphic that I just noticed is that the only seemingly"continous" gec is the one that goes to to water pipe. Wheres the "continous" one from the ground rod continous and terminated only at the neutral?If I did it this way I would get tagged every time.
 

roger

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Fl
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Stew, there is only "ONE" GEC, that is the conductor to the water pipe in the graphic, all other conductors are jumpers. If your inspectors are tagging you for the jumpers not being continuous they are wrong.

Roger
 

George Stolz

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Location
Windsor, CO NEC: 2017
Occupation
Service Manager
Here's another link to the picture Roger posted.

The GEC connects the GES to the system neutral. The electrodes of the GES can be bonded together with bonding jumpers. They can be connected directly to the system neutral with dedicated GEC's. 250.64(F) gives us options. Any convenient one, or all of them individually.

Don't fret, it took me a while for the bonding jumper thing to process too. For me, it kinda turned my world on it's head for a couple hours. :)
 

hillbilly

Senior Member
Thanks for clearing that up Roger. That is my opinion too. I sometimes splice at the first ground rod (or water line) when I need to get rid of some short pieces of #4, or when up-grading a service. I've never been tagged for doing this. With copper prices where they are, that extra ground clamp pays off.
steve
 

stew

Senior Member
thats what i said is that the only continous one is the water pipe conductor which is of course not adequate to ful fill code requirements for gec. at least one and 99% of the time 2 ground rods are required as well. If I were to tag on to the water pipe and run to the first ground rod we would be tagged for not being continous and not terminating at the neutral .inspector right or wrong thats they way they seem to see it here.
 
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