While Anchor Guard was one of the major forces behind EIA/TIA 222 F
which precluded the use of copper in the grounding system, I think they
tried to solve a complex issue simplistically. There is more to the situation
than dissimilar metals (copper and galvanized [zinc]) being near each other.
Unanswered in my mind is how close to (or actually how faraway from) each
othjer they have to be before problems might occur.
The corrosivity of the soil is another issue left unaddressed. One should
measure
the pH of the soil, preferably at the depth at which the grounding system is to
be
installed. The pH testers sold at spa and swimming pool places will suffice for
ascertaining whether your soil is acidic or alkaline. If your soil is acidic
(most of
the eastern US is), you want to go with galvanized because the acid will attack
the
copper. If your soil is alkaline, however, you want to avoid
galvanized/tin/aluminum
grounding components because those metals are quickly attacked in that
environment.
73,
Bob Wanderer AA0CY
ex PolyPhaser Sr Appl Engr
now (Thank God) back in the cable television industry
but had to leave Nevada and move to Seattle.
----------
From: k0il@qsl.net[SMTP:EEDWARDS@oppd.com]
Sent: Friday, May 01, 1998 6:54 AM
To: rfi@contesting.com
Subject: Re: [RFI] Copper clad or Galvanized steel ground rods???
>Another question, which is better in clay type of topsoil? I currently
>have several copper clad one out and I assume I should continue to use
>copper clad on the ones I am soon to add?
I've used only copper clad rods since pure copper won't go straight into the
ground here with clay soil. I usually have to use a sledge hammer to get 'em
all the way in. At home I use 8 ft copper clad. At work I use two coupled 10
ft rods for 20 feet total.
Remember to add grounding to tower guys also; yet another path for lightning
to follow away from your shack.
I understand the new EIA tower standards now specifies galvanized steel rods,
but I think that is due to corrosion of tower anchors in certain parts of the
USA. Copper clad should work okay for radials in most of the USA.
There's a company that specializes in this area called "AnchorGaurd". They
have a good web page with lot's of pictures of corroded tower anchors and the
catastrophic results. Also shows a map that shows the areas of the country
that have corrosive soils. You may want to use galvanized steel rods on your
guy wire's ground rods if you live in those areas. Apparently Norht & South
Dakotas have really bad corrosive soils as does alot of Texas/Louisiana. See:
www.anchorgaurd.com for lot's more info.
73,
de ed -- K0iL
k0il@qsl.net
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