I know this is getting a bit off topic, but I felt compelled to reply! I
noticed the thread made the jump over to the TowerTalk reflector. Probably
more appropriate than the RFI reflector. So here's my last one on the subject
here.
Brad KZ5Q wrote:
>Just My 2 cents worth: or : Galvanized won't work in South Louisiana.
>In this area of the country, I have seen Galvanized pipe destroyed
>in less than 6 months. In over 40 years I have yet to see a piece
>of copper destroyed. Have seen many a time, a copper water line
>and black steel or galv steel gas line , side by side and the steel line
^^^^^^^^^^^^
>every time was damaged due to corrossion. Distance between them
>did not matter. From 1" to 50 feet at same depth, it made no difference.
Howdy Brad:
Looks like you've made a case FOR using galvanized ground rods even though you
don't like the idea:
If your installing "galvanized" towers and "galvanized" guy anchors side by
side with copper ground rods, then it looks like you're creating an
electrochemical corrosion cell, and "accelerating" the already corrosive
effects on the galvanized steel. So unless you're using copper for towers and
copper for guy anchors, I'd use the SAME material as the guy anchors/towers
for ground rods driven within several feet of the anchors.
Yes, they'll corrode. But won't they corrode anyway? And wouldn't it corrode
faster if dissimilar metals are used as you pointed out seeing in pipes that
were side by side? And would it not be better for the ground rod to corrode
than the guy anchor holding up your towers? It's a hellava lot easier to
replace ground rods than anchors! It's the copper rod that causes the
galvanized steel anchor to corrode at a faster than normal rate, which you've
pointed out already corrodes pretty fast there in Louisiana.
>Might need to see if we need anodes on Towers
I think that's what the company AnchorGuard sells to slow corrosion process
down a little.
It is clear there is a BIG problem in some areas with corrosion. The two most
catastrophic tower failures in the last few years that I've heard of were in
North Dakota and Louisiana where 1200 ft plus towers collapsed killing some
tower crews. I think these towers were built pre-EIA-222 'F' so they probably
used lots of copper rods everywhere!
It's probably OK to use copper rods (with tinned copper wire) in most places
in the antenna system like for the interconnecting grounding between ham
shack, AC, telco, tower radials, and so on; however, I'd definitely consider
using galvanized steel rods for the grounding of guy wires near galvanized
steel guy anchors and maybe the tower base, at least in certain parts of the
country.
I'm not a chemical engineer, just an electonics geek. SO I'm definitely NOT
an expert in this area. The new EIA standards were reviewed by those chemical
experts who are in-the-know. It is possible they made a mistake, but based on
everything I've read in relation to recent tower failures, I think we either
have to go with what they're saying, or find some other material that's as
strong as steel and less prone to corrosion to build our towers with.
Aluminum towers probably look real attractive to hams in ND, LA, & TX!
There's a lot of good ideas and information on the AnchorGuard web page for
anyone installing a tower or ground system without actually spending big bucks
buying their products. I think if you look at there site, you'll come to the
same conclusions I have in my previous paragraph.
73,
de ed -- K0iL
k0il@qsl.net
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