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Posted By: Bravo ground fence - 09/30/13 05:26 PM
Hello,

I have a metal chain link fence inside a building that surrounds process equipment. Does the fence have to be grounded? I cant find req's in the NEC.

Thanks in advance

Posted By: gfretwell Re: ground fence - 09/30/13 06:36 PM
A general rule that is not always fleshed out well in the language is that you should bond anything that is likely to be energized. If this fence is not near any energized conductors, it probably does not need to be bonded.

As an aside, it is probably fairly well "grounded" by the posts in the ground but that is not the same as bonded.

Places where I see fences bonded is where there is significant radiated power. This can be a radio/TV transmitter or just a big distribution transformer farm.

680 will also require that a fence be bonded if it is <5' from the water.
Posted By: Alan Belson Re: ground fence - 09/30/13 11:29 PM
A friend bought an old farmhouse cheap, cheap because a new 400,000 volt line from a new atomic reactor passed close by [200 yards, heading for Italy]- and destroyed local realty values. Now the poco has bonded the neighbor's entire sheet metal barns and machinery shed. Is that why? Should he do the same to his barn, do you think?
Posted By: mbhydro Re: ground fence - 09/30/13 11:48 PM
I wonder if they are worried about tingle voltage affecting the livestock so that's why the POCO paid for the grounding?
Posted By: gfretwell Re: ground fence - 10/01/13 01:18 AM
I have a 250KV and two 48KV lines running behind my house and I can't seem to detect any strange voltage problems. I tried every YouTube trick I have seen to light a fluorescent tube with no joy.
I even tried stringing 100' of THHN directly under the poles with various terminations or simply floating ... nothing.

It is a little disappointing actually. I thought I could get free lights for my boat house, virtually directly under the line.
Posted By: HotLine1 Re: ground fence - 10/01/13 01:45 AM
Not on YouTube, but:
Changing 10'HO lamps in a sign, my 'ground man' yells on the two-way.."the bulb is lit!!".

End of the tube was 3'+/- from a 13.2 primary. It was not 'bright' but it was glowing!

OOOPS!
Posted By: gfretwell Re: ground fence - 10/01/13 01:55 AM
The poles are marked 115' but I assume 15' or more is in the ground. I suppose I could climb up a little closer and try. wink
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