There's some truth to what you say, but bear in mind two things:
1. The tower in question has four 50' 1/0 buried radials with 8'
ground rods Cadwelded every 16 feet. Quite a bit of dissipation capability
there.
2. Regarding the 265' 1/0 wire that connects the tower and shack, I'm
sure it helps, but most of the lightning energy will be dissipated in the
first 75'-80'.
I would submit that the remaining 190 feet of expensive 1/0 wire serves no
purpose, nor does the connection at the shack end.
73, Dick WC1M
From: john nistico [mailto:electric911inc@hotmail.com]
Sent: Tuesday, January 22, 2013 7:11 PM
To: Vincent Weal; wc1m73@gmail.com
Cc: towertalk@contesting.com
Subject: RE: [TowerTalk] bonding to AC power box or inside fuse panel?
When it comes to lightning protection more is better. If the 1/0 copper wire
was bare in the trench it would dissipate a lightning strike much better.
This is what we do on houses all the time.
John J. Nistico
911 Electric Inc.
516.356.6071
> Date: Tue, 22 Jan 2013 17:37:34 -0500
> From: k4jc@arrl.net
> To: wc1m73@gmail.com
> CC: towertalk@contesting.com
> Subject: Re: [TowerTalk] bonding to AC power box or inside fuse panel?
>
> Dick, I want to thank you for this post. I have been trying to find an
> answer to this question for years, but no one seemed to have a definitive
> answer. Can you tell me where I can find the article you referred to?
>
> My tower is going to be 175 feet from the shack and I wasn't looking
> forward to dropping all that dough on grounding wire!
>
> 73, Vince K4JC
>
> > -----Original Message-----
> >"Another example is bonding the tower ground to the single-point ground
at
> the house. My first tower farm is 265' from the house. Being new to tower
> construction, I laid 265 feet of 1/0 ground wire in the trench running
> between the two locations in order to bond the ground systems. This was
not
> cheap, to say the least (though it was before the big run up in copper
> prices.) Later, I read an article by Polyphaser that said if the ground
> systems are more than 75' apart it does no good to bond them -- the wire
> inductance will be too high to make an effective connection. With this in
> mind, when I installed my second tower system in a different location 220'
> from the house, I did not run a separate ground wire. The Polyphaser
> argument made sense to me. Also, there are two runs of 1-5/8" hardline in
> the trench, and the gigantic copper shields on those babies surely provide
> a lower inductance path between the tower and house than a 1/0 wire would
> -- if, in fact, any wire has low enough inductance at that length to be
> effective.
>
> 73, Dick WC1M"
> _______________________________________________
>
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