I personally think it's the "we gotta DO something" complex.
There are too many issues for a "one method fits all" solution. As one issue:
The pH of the soil: acidic (eastern US) eats copper but not alum/tin/galv.
Alkaline in
the western US will eat alum/tin/galv and loves copper.
73, Bob AA0CY
----------
From: Bill Hinkle[SMTP:kb3aug@juno.com]
Sent: Friday, April 25, 1997 8:18 PM
To: n3rr@erols.com
Cc: ac4gt@juno.com; donovanf@sgate.com; btippett@hub.infoave.net;
towertalk@contesting.com
Subject: Re: [TowerTalk] Galvanized ground rods. WAS: Verticals of ROHN 25
When I lived in Southern Maryland and installed my towers I decided to
look at the ground the power company had installed. It was sticking out
of the ground about 6 to 10 inches and the clamp was loose. I thought
well, I'l just dig down all around it, drive it in deeper and tighten
everything up. It was a galvanized steel rod and for the 2 feet below
the ground where I dug down, the rod was rusted! It didn't look like a
good ground to me. So I tied it in to another copper rod about 5 feet
away. Did I do wrong? After seeing that, I thought I would never use a
galvanized rod for anything. My thoughts were, that galvanized was a
cheap way to ground something. Galvanizing will rust, so how can this be
the new standard?
Bill, KB3AUG
On Thu, 24 Apr 1997 06:34:45 -0700 Bill Hider <n3rr@erols.com> writes:
>nathan c tart wrote:
>>
>> On Wed, 23 Apr 1997 20:20:00 -0400 (EDT) Frank Donovan
>> <donovanf@sgate.com> writes:
>> >As a matter of interest to Towertalkians, the new version of
>> >EIA/TIA-222
>> >specifies that copper wire SHALL NOT be used for ground wires,
>ground
>> >rods
>> >or ground clamps. All new towers installed under EIA/TIA-222
>> >specifications must use galvanized ground rods, galvanized steel
>wire
>> >(ie
>> >guy wire!) for grounding conductors, and galvanized connectors or
>> >exothermically welded connections. Tinned copper wire may be
>> >substituted
>> >for galvanized steel wire when the conductor must be buried. Bare
>> >copper
>> >is no longer allowed in any grounding application, either at the
>tower
>> >base or at the guy anchors.
>> >
>> >This change came about as a result of research that demonstrated
>that
>> >copper ground rods in proximity to tower foundations and steel guy
>> >anchors
>> >tended to accelerate the corrosion of the steel members, leading to
>> >sudden
>> >catastrophic failure!
>> >
>> >73
>> >Frank
>> >W3LPL
>> >donovanf@sgate.com
>> >
>> >
>> >--
>> >FAQ on WWW:
>http://www.contesting.com/towertalkfaq.html
>> >Submissions: towertalk@contesting.com
>> >Administrative requests: towertalk-REQUEST@contesting.com
>> >Problems: owner-towertalk@contesting.com
>> >
>>
>> How many millions of ground rods (the 8 ft commercial
>> kind are in the ground now......one are every cable TV
>> junction box (for example).... I have three new ones
>> (never used for spares)... However looking at mos
>> commercial installations.. the one I have seen are in
>> compliance with the aforementioned code......
>> We remember there are grounds for lightening and grounds
>> for signal reflection... one could carry on with the engineering
>> talk to the end of time etc.......Is the COMMON GROUND
>> the best for all occasions????????????
>>
>> Nate..........
>>
>> PS: My tower goes straifht into the earth... if it rots
>> OLE WELL... (it will outlast me.. or at least my dessire to use it)
>>
>> --
>> FAQ on WWW:
>http://www.contesting.com/towertalkfaq.html
>> Submissions: towertalk@contesting.com
>> Administrative requests: towertalk-REQUEST@contesting.com
>> Problems: owner-towertalk@contesting.com
>
>Nate,
>
>It's not clear from your response to Frank that you understood his
>point. It's not the corrosion of the copper ground rod that's the
>issue...It's corrosion and subsequent structural failure of the tower
>and/or its associated steel guy member!!!
>
>This specification came about after years of study of experiencial
>information: READ: TOWER FAILURES!! That's why there are millions of
>copper ground rods in the ground. That does not mean that those
>millions of ground rods should have been put in the ground, it just
>means that we now know better.
>
>The spec is: ANSI/EIA/TIA-222-F, June 1996.
>
>73!
>
>Bill, N3RR@EROLS.COM
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-REQUEST@contesting.com
>Problems: owner-towertalk@contesting.com
>
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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