[TowerTalk] Cadweld vs clamps

[Bill Turner]

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On Sat, 25 Oct 2014 17:55:18 -0400, you wrote:

> The antenna ground system ties 
>to both buildings, essentially tying their service grounds together 
>through a network of over 600 feet of bare #2 cad welded to 32 or 33 8' 
>ground rods.  

REPLY:

And therein lies the problem. Multiple grounds which are physically
separate but which are wired together.  That is asking for trouble and
that is why the NEC requires a single point ground.  Having separate
SPG's that are wired together is NOT a true SPG. 

The ground itself is not a perfect conductor, far from it. When
lightning hits one of the grounds, it elevates that individual ground
potential well above the other grounds in the area, and if they are
wired together, guess what happens? Current flows between them and
that is BAD NEWS.  

At my QTH, the tower and antennas have their own ground and the house
has its own ground, and when lightning is present they are totally
disconnected from each other. I believe that is the only safe way to
go.

73, Bill W6WRT