Building Ground Ring

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infinity

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Hi All,

Is building ground ring primarily used to protect buildings from lightning?

Thanks,
EE
If they are I would be curious to know if they're more effective than a CEE. Since they're required to encircle the entire building they seem to be somewhat impractical when the building is very large.
 

roger

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Since they're required to encircle the entire building they seem to be somewhat impractical when the building is very large.
We were on a project where the ground ring was upwards of $100,000.00, a big waste of money but they had plenty to spend.

Roger
 

roger

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Was the ground ring required to help meet a required measured ground resistance value?
No, it was just an engineers belief that it would help keep noise down and (this is sick) help clear faults, I specifically asked him about this and didn't get much of an answer. It boiled down to he thought his horse was high enough that he shouldn't be questioned.

Roger
 

infinity

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No, it was just an engineers belief that it would help keep noise down and (this is sick) help clear faults, I specifically asked him about this and didn't get much of an answer. It boiled down to he thought his horse was high enough that he shouldn't be questioned.

Roger

Sounds like someone who would waste 100K over bad engineering. :giggle:
 

brian john

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If they are I would be curious to know if they're more effective than a CEE. Since they're required to encircle the entire building they seem to be somewhat impractical when the building is very large.
I see them all the time 250 KCMIL 5' off the footers 10' ground rods every 10-25 feet 2000' perimeter and larger, then the engineer specifies a 3-point test in an area where you cannot go out more than a few hundred feet.
 

don_resqcapt19

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A common industrial spec around here is a 4/0 ground ring with ground rods at the corners and a 2/0 bonding jumper to each steel corner column and to every other column between the corners.
 
Having a long electrode and/or an electrode encircling something at least kinda makes a little sense from an earth resistance
(or course we can argue about what lower earth resistance gets you) and step potential standpoint, but what doesnt make any sense is the large wire size often used. I also dont really get what the ground rods are doing if you already have thousands of feet of copper in contact with the earth
 

brian john

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Having a long electrode and/or an electrode encircling something at least kinda makes a little sense from an earth resistance
(or course we can argue about what lower earth resistance gets you) and step potential standpoint, but what doesnt make any sense is the large wire size often used. I also dont really get what the ground rods are doing if you already have thousands of feet of copper in contact with the earth
And all this tied to a concrete footer.
 

Hv&Lv

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Sounds like an engineer is doing more CYA than actual engineering...
 

infinity

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No, they really think this stuff is important. Dirt Worshipers are slavish and unrepentant in their devotion.

Sounds like their designs are due to ignorance but it makes them sleep better at night. When they say it helps with clearing faults like Roger mentioned then one can see that they're misinformed. A large building will have thousands of feet of rebar tied together and encased in concrete to form the CEE, not sure why anything more is needed.

With the way the NEC has grown into more and more code changes without any substantiation I'm surprised the dirt worshipers haven't got the GES requirements expanded. :rolleyes:
 
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