Wow!
I think I'll listen to almost anything a man with a 500-foot tower in
the back yard says! What a dream!
Sounds like the 2/0 wire is the route to go.
Here, I think the water table is at about four to six feet, so I should
be OK with 8-foot ground rods. In Indiana, where I had an 80-foot
tower, I actually had a well-drilling company come out and sink a pipe
to about 30 feet for a ground. Here, I am planning to put in two
60-foot ground radials with five ground rods each, on two of the legs,
and the attachment to the third leg will be the run to the ground system
outside the ham shack (around 100 feet).
Doc, N9AM
----- Original Message -----
From: Paul Finch <paulfinch@email.msn.com>
To: Richard Spindler <spindoc@digital.net>
Sent: Wednesday, October 27, 1999 1:15 PM
Subject: Re: [TowerTalk] Grounding Wire/Strip
> Richard,
> I have a 500 foot tower in my back yard, the tower crew used three
"round"
> cables of about 2/0 cable to connect to the ground rods about 6 feet
form
> the base of the tower. They did all the welding with CadWeld
products.
>
> I too have run the gambit of looking for the copper flashing, most
people
> use it only in the tower building to run around the baseboard so
customers
> can tie there ground to it with just a sheet metal screw. It seems to
work
> OK. I was really lucky, I found 100 foot of it at a Hamfest for 30
dollars,
> needless to say I did not quibble about the price!
>
> I also have a 30 foot deep wet well that I had dug with a 4 inch
copper pipe
> as a sort of well casing also at 30 feet. I installed a copper flange
to
> the top then I came off the flange with two 500MCM cables (about 1
inch
> copper cable) to the two closest legs of the tower. Seems to work
well,
> have not taken a hit so far and we had some pretty fierce lightning
last
> spring here in Texas.
>
> As most of the people here on TT will tell you, keep the bends gentle,
no 90
> degree sharp turns.
>
> This is overkill I know for most Ham installations but it may give you
some
> ideas.
>
> Good Luck, hope this helps,
>
> Paul Finch
> WB5IDM
> Azle Communications
>
>
> ----- Original Message -----
> From: Richard Spindler <spindoc@digital.net>
> To: TowerTalk Reflector <towertalk@contesting.com>
> Sent: Tuesday, October 26, 1999 11:42 AM
> Subject: [TowerTalk] Grounding Wire/Strip
>
>
> >
> > Boy. This just gets complicateder and complicateder.
> >
> > I was all set to do my ground system and grounding radials with #6
wire,
> > and then in reading another treatise on grounding, I am told that
this
> > is a major mistake because of the inductance which will cause
lightning
> > to look for another route to ground. The PolyPhaser literature says
> > that what really should be used is minimum 1-1/2" flat copper strip,
and
> > I have read another couple sources which repeat that, and say that
if
> > wire is to be used, the minimum size should be 2/0.
> >
> > The thing is: that kind of shoots my neat plan with the CADWelding
of
> > the ground rods, unless one can CADWeld the copper strip. Also, the
> > copper strip is REALLY expensive. I think I am looking at around
$400
> > for the amount I would need, and I wonder how long it would last
> > underground versus big wire; I would think a lot less long.
> >
> > I recall reading something somewhere about "copper flashing."
Sounds
> > like something that might be used in construction, and maybe on the
same
> > principle, but cheaper than the PolyPhaser strip?
> >
> > I might be back to brazing copper strip to ground rods instead of
the
> > pyrotechnics, after all. I have a little common sense voice in the
back
> > of my head that says wire would probably be OK if I get big wire,
but
> > 2/0?
> >
> > This system is certain to take lightning strikes, so I do want to do
it
> > right. Anybody got some ideas or data on this dilemma?
> >
> >
> > --
> > FAQ on WWW:
http://www.contesting.com/towertalkfaq.html
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> > Problems: owner-towertalk@contesting.com
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> >
>
>
>
>
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