[Top] [All Lists]


To: <>
Subject: [TowerTalk] TOWER METALS
From: "K0DAN" <>
Date: Mon, 25 Oct 2010 11:01:40 -0500
List-post: <">>
I'm enhancing my 12-year-old tower ground system. I have three copper-clad 
ground rods adjacent to the tower legs, each ground rod has a short run of 
#4 copper wire to each tower leg (galvanized steel) at the base. This 
existing ground system also connects to a copper plate inside a Nema box 
about 6' from the tower, and to a 130' buried run to another Nema box with 
copper plate near the shack, and ultimately to the single-point-ground bus 
at the shack.

I plan to add more ground rods at the tower base and shack, also create more 
of a grid between tower legs & ground rods. Also add more radials beneath 
the tower for use with planned shunt-fed tower. I have two coils of copper 
strap...will use these in lieu of wire (until I run out of strap).

The tower base, bolts, and other hardware are all galvanized. Tower base 
cage & rebar are embedded in approx 12 yd of concrete. Soil here (midwest) 
is about a foot of black dirt atop clay. None of the galvanized is in 
contact with the soil. Can't say what the soil chemistry is, but years ago I 
lost a guy anchor (different tower...R.I.P.) to galvanic action, so the soil 
is corrosive in some manner. Other than the copper-clad ground rods, 
everything in the soil is copper.

I have had no previous corrosion trouble connecting the copper ground wires 
to the galvanized legs/bolts, but since I'm refurbishing, now would be the 
time to replace/add hardware if appropriate. All the ground rods are 
copper-clad steel...I have no idea what condition the sub-soil rods are in.

OK so the question is....what's the right intermediate metal to use to 
connect the copper wire/rods to the galvanized steel tower legs? Brass 
washers? Stainless?

And as to the old copper-clad ground rods, is there a way to tell if they 
even exist anymore? (Yes, I can see them, but are they still 8 foot x 1/2"?)


Tnx es 73



TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>