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
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
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