In <970416221945_873197652@emout01.mail.aol.com>, on 04/16/97
at 10:22 PM, K7LXC@aol.com said:
> The practical hemisphere of influence for ground rods is twice
>their length. In other words, a ten foot ground rod has a hemisphere
>of approximately 20 feet. So does the adjoining ground rod. The rods
>should be spaced 20 feet apart so that their respective hemispheres
>just touch. If the rods are closer together, you aren't getting the
>maximum effectiveness from them. Farther apart is better than closer
>together.
> If your question was "how far to space the ground rods from the
>tower" then the answer is to get them as close as practical to the
>tower legs. The connecting wire should have big lazy bends in it and
>not sharp ones. The sharp bends are high impedance points which is
>what you're tryin to avoid.
Which is it, Steve? If ground rods should be four times their length
from the adjacent rod how can they be as close as practical to the
tower legs?
For example, if I were to install three eight foot ground rods on a
tower (one on each leg), should they all be adjacent to the base
(about 6' apart if they're outside the concrete base) or should they
be spaced on a 32' triangle (with heavy cables around the triangle
and connecting a rod to each leg)?
I can't believe a single eight to 10 foot ground rod is sufficient
even if the tower, rebar and ground rod are bonded together.
73,
... Joe Subich, W8IK ex-AD8I
<W8IK@ibm.net>
<jsubich@ibm.net>
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