Ground rods in sidewalk

[infinity]

According to 250.10 every grounding or bonding connection is required to be protected from damage - even exposed water line grounds. But they apparently aren't in any danger

That's why I say that merely being exposed is not enough to say it's in danger of being damaged. And I've never seen an AHJ who thought it's a danger to have a ground rod acorn above dirt, concrete, asphalt, or anything else

You're confusing the two sections as they do not say the same thing. All ground clamps when subject to physical damage require protection regardless of the electrode type {250.10}. If they're not subject to physical damage like a typical standard water pipe clamp then nothing is required. Ground rods not driven below ground are automatically required to be protected.

250.53(G) The upper end of the electrode shall be flush with or below ground level unless the above ground end and the grounding electrode conductor attachment are protected against physical damage as specified in 250.10.

 

[Open Neutral]

If the sidewalk has rebar, does using that constitute a Ufer ground?

 

[infinity]

If the sidewalk has rebar, does using that constitute a Ufer ground?

Pretty long stretch to call a sidewalk a footing or concrete foundation.

 

[James L]

You're confusing the two sections as they do not say the same thing. All ground clamps when subject to physical damage require protection regardless of the electrode type {250.10}. If they're not subject to physical damage like a typical standard water pipe clamp then nothing is required. Ground rods not driven below ground are automatically required to be protected.

I'm well aware that they don't say the same thing. I think Don is conflating the two.

I'm simply saying that 250.53 simply adds a note about protecting from physical damage "according to 250.10". But 250.10 mentions, generically, "ground clamps or other fittings" which is all-inclusive of any type of clamp.

But it doesn't stop there. It's "any clamp that's exposed to physical damage" has to be covered, buried, et al

It's not "if it's exposed"
It's "IF" there's any danger of being damaged.

Being exposed (or uncovered) is not enough to claim it's exposed to physical damage, imho.

 

[Njonescontracting]

I'm going to probably call the AHJ and see if I even need to add a rod on a panel replacement. (and if so where they will allow me to put it... Or maybe 2) Never had this issue come up before. Other counties could care less if there is any rod as long as there is a connection at water. But we will see. Hopefully they don't take a week to get back to me.... Thanks for the help guys!

Sent from my SM-G981U using Tapatalk

 

[Open Neutral]

If you use a CadWeld, there's no clamp to argue about.....

 

[LarryFine]

Is the floor of this house over a crawlspace, is it on slab, or is it below grade?

 

[Eddie702]

Can't you drive them horizontal from within the building?. If there are no ground water issues

 

[LarryFine]

Or even in the corner where the wall meets the sidewalk, at an angle under the building.

 

[jusme123]

NEC requires two rods unless you can prove that the single rod has a resistance of 25Ω or less.

I’d love for someone to explain to me how that requirement makes any sense, what if it measures 800 Ohms after installing second ground rod? Measuring isn’t a requirement after second rod is installed.

 

[LarryFine]

It would be easier to explain the workings of the female mind. <--- joke reference, no sexism intended

 

[infinity]

I’d love for someone to explain to me how that requirement makes any sense, what if it measures 800 Ohms after installing second ground rod? Measuring isn’t a requirement after second rod is installed.

No one knows the answer to that question. Just pound in two rods and go home.

 

[Fred B]

I’d love for someone to explain to me how that requirement makes any sense, what if it measures 800 Ohms after installing second ground rod? Measuring isn’t a requirement after second rod is installed.

Dump some water on them and remeasure, dry ground will read higher than damp/wet ground, but better yet:
Don't meter after a second rod installed, (it'll only make you crazy). Code only calls for metered reading for justification to provide less than 2 ground rods, I see no requirements that says you must get 25ohms for the grounding system overall, only for the justification already mentioned.

 

[wwhitney]

This language eliminate looking at the "exposed to physical damage" language in 250.10. It clearly requires the exposed rod to be protected by one of the methods in 250.10, even where you do not think it is exposed to physical damage. The language in 250.53(A)(4) is telling you that the end of a rod above grade, is always exposed to physical damage.

Disagree. If the language in 250.53(A)(4) were, in fact "unless the aboveground end and the GEC are protected by one of the methods in 250.10" then I would agree with you.

But the language is "unless the aboveground end and the GEC are protected against physical damage as specified in 250.10." Section 250.10 always applies to the clamp connecting the GEC and the end of the ground rod, as it is a "ground clamp or other fitting." 250.53(A)(4) just adds the above ground end of the ground rod and the GEC to the things subject to 250.10. If the above ground end and the GEC are not "exposed to physical damage", then they satisfy 250.10 without further protection.

Cheers, Wayne

 

[acrwc10]

NEC requires two rods unless you can prove that the single rod has a resistance of 25Ω or less.

I had an inspector once tell me I needed 3rd party testing on the ground rod, to prove less than 25 ohms, if I wanted to avoid driving the second rod. Driving the rod flush is a must to keep it from being an empanelment hazard. The building code does allow you to encroach 4” or less into the walkway below 80”

 

[acrwc10]

It is often over looked that all the protruding rebar is capped during construction because it is an empanelment hazard but a 1/2” rod poking out of the ground in a walkway goes in-noticed. We had an electrician put one through his hand in 1983.
also a young man on a job died when a piece of rebar sticking up less than 3” went through his heart. As far as the 25 OHMs or less rule, that goes back to the Telegraph days from what I have heard, just a number that stuck over time. It is right up there with putting a GEC wrapped around the base of a light post, in a drilled hole. How is a #6 CU helpful for a 20 amp lighting circuit that already has an equipment ground running to it? (But I don’t want to highjack the thread)

 

[don_resqcapt19]

I'm well aware that they don't say the same thing. I think Don is conflating the two.

I'm simply saying that 250.53 simply adds a note about protecting from physical damage "according to 250.10". But 250.10 mentions, generically, "ground clamps or other fittings" which is all-inclusive of any type of clamp.

But it doesn't stop there. It's "any clamp that's exposed to physical damage" has to be covered, buried, et al

It's not "if it's exposed"
It's "IF" there's any danger of being damaged.

Being exposed (or uncovered) is not enough to claim it's exposed to physical damage, imho.

I am simply saying that the connection to a ground rod with the upper end above grade MUST be protected by the method specified in 250.10. I am not making any comment on the application of 250.10 to other GEC connections.

 

[don_resqcapt19]

Disagree. If the language in 250.53(A)(4) were, in fact "unless the aboveground end and the GEC are protected by one of the methods in 250.10" then I would agree with you.

But the language is "unless the aboveground end and the GEC are protected against physical damage as specified in 250.10." Section 250.10 always applies to the clamp connecting the GEC and the end of the ground rod, as it is a "ground clamp or other fitting." 250.53(A)(4) just adds the above ground end of the ground rod and the GEC to the things subject to 250.10. If the above ground end and the GEC are not "exposed to physical damage", then they satisfy 250.10 without further protection.

Cheers, Wayne

Not going to agree on this one.

 

[James L]

I am simply saying that the connection to a ground rod with the upper end above grade MUST be protected by the method specified in 250.10.

I've never met anyone else who reads it that way.

 

[Nuber]

Can't you drive them horizontal from within the building?. If there are no ground water issues

No.

see 250.53(A)(4) - horizontal rods can only be installed in a trench and be code compliant