Wiring the J-bolts and rebar is generally not considered adequate for lightning
protection! Welding or exothermic bonding is used for the commercial towers
I've seen.
http://www.polyphaser.com/techdocs/Ufer%20and%20Tower%20Grounding.pdf
The Ufer tower base ground should only be used to supplement standard ground
rods & radials.
And the current ARRL Antenna Books still recommend "minimizing the possibility
of direct discharge path for lightning through the base." I certainly don't
consider ARRL books a definitive reference, but unless a ham understands the
details of Ufer grounding, it's probably still good advice to follow.
Steve, W3AHL
Message: 5
Date: Fri, 12 Mar 2010 12:38:44 -0500
From: "Gary Schafer" <garyschafer@comcast.net>
Subject: Re: [TowerTalk] tower & antenna project questions
To: "'Tower and HF antenna construction topics.'"
<towertalk@contesting.com>, <wisecrafter@suddenlink.net>
Message-ID: <20100312173843.2913D1B60BDF@dayton.contesting.com>
Content-Type: text/plain; charset="us-ascii"
A Ufer ground is fine for a tower as long as it is not the only ground. You
still need ground rods outside of the tower base connected to the tower.
The J bolts for the tower mounting pad should be wired to the rebar inside
of the concrete. That is sufficient connection to the rebar for a Ufer
ground. You don't want any unconnected rebar gaps inside the foundation that
could arc.
73
Gary K4FMX
...snip...
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