John D. Peters wrote:
>
> > W3LPL wrote:
> > >
> > > 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
>
> Thanks Frank.
>
> I presume that this change is only of interest to those with GUYED
> towers? I can see no reason to change from #4 solid copper wire, or
> copper strap to copper clad steel ground rods if the tower is self
> supporting.
>
> The legs of my tower are certainly not corroding away to "pencil"
> diameter.
>
> Is there some other consideration that might apply to self supporting
> towers?
>
> 73 John K1ER
>
> --
> FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
ANSI/EIA/TIA-222-F applies to ALL steel towers, guyed or self
supported. The issue is bi-metallic corrosion, not how thick the tower
legs are.
By the way, the title of this publication is:
"Structural Standards for Steel Antenna Towers and Antenna Supporting
Structures"
Someone on this reflector asked about aluminum. Someone else said it
was OK if you checked the connections regularly. Well, before I knew
better, I used aluminum ground wire connected to my copper ground stakes
and to my steel tower. In a couple years my # 10 aluminum wire was
non-existent.
Why? It had been eaten away by the current flowing from the "battery"
set up by the copper rod in the ground and the short circuit formed by
the aluminum wire.
Always use what the experts recommend. In this case its the American
National Standards Institute, the Electronic Industries Association and
the Telecommunications Industry Association. Why someone would try to
make assumptions and rationalizations which would put them and their
installation at odds with these experts is beyond me...
OH, ANSI/TIA/EIA-222-F-1996 is the "official" name of this copywritten
document. And can be obtained from Global Engineering Documents.
(1-800-854-7179) or 303-397-7956 for $80.00 (as of July 1996 when I
obtained my copy).
Bill, N3RR
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
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