Grounding Of Fence

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Alwayslearningelec

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Have about 1000' of fence that needs to be grounded. This detail seems to indicate a bare conductor daisy chained between ground rods. Kind of like a grounding/counterpoise loop.
Is that needed? Couldn't you just go from the fence to the ground rod at each location?
If you need the conductor between all ground rods how would you size? THey do show 4/0 but only from ground rod to fence. Thanks
 

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That’s about the way we ground substation fencing, although we wouldn’t use 1/0 up top. We use #2.
The razor or barb wire can’t carry that much.
 
Also, the posts are 8' OC. It's required to ground every post? The fence footage is actually more ...about 5,000'.

That's a lot of grounding.
 
Unless there are high voltage power lines over the fence, which I'm sure there isn't at an airport, what is the point?
 
petersonra said:
What is the point of grounding the fence? what possible benefit is there to doing so?
Click to expand...
4x4dually said:
Unless there are high voltage power lines over the fence, which I'm sure there isn't at an airport, what is the point?
Click to expand...
Well, let me back up… if it’s an FAA owned facility it’s required.
Airports that aren’t FAA owned don’t have to require grounded fences

I saw 5000’ of fence, that’s a pretty big fence. A lot of wind can blow through a 5000’ fence.
there’s also lightning, underground/ overhead power lines, etc..
 
The drawing calla for exothermic weld at the ground rod? I thought you just install ground rod clamp and the wire can attach to that??

How would a weld attach to the ground rod? A "T"?? Thanks
 
I wonder....airport lighting uses high voltage series strings for the runway lights. If there is a ground fault in such a system, could it couple to the fence and create local areas of high step potential if there isn't good grounding?

-Jon
 
Hv&Lv said:
Well, let me back up… if it’s an FAA owned facility it’s required.
Airports that aren’t FAA owned don’t have to require grounded fences

I saw 5000’ of fence, that’s a pretty big fence. A lot of wind can blow through a 5000’ fence.
there’s also lightning, underground/ overhead power lines, etc..
Click to expand...
i have seen these details on many projects and have always considered them useless, other than fencing surrounding substation (or as you said maybe in vicinity of OH power lines.

But I keep seeing it spec'd so obviously I am in the minority.
 
What tests are performed when installing ground rods in this situation? Whatever test is performed would it be at each fence post where there's a ground rod or an overall test of the "systems"?
 
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