Don't use braided cable for lightning dissipation, especially outdoors
or in any environment in which corrosion will occur.
The high frequency components will be concentrated on the outside of any
conductor. That is skin effect. Approximately half of the energy in a
lightning strike is at frequency over 1 MHz. In a braided cable,
current must pass from strand to strand, at the points of contact. That
increases the resistive component of impedance and becomes worse as the
surfaces corrode. Bare,solid, number 6 copper is recommended for these
ground radials for current capacity and mechanical durability. They
should be buried, to take advantage of conductance from the wires to the
soil and for protection from mechanical damage.
73 de WOØW
Dr M J DiGirolamo wrote:
>Dear TT Colleagues,
> have decided to use a heavy
>braided tinned copper cable as the radial for each of these legs. I have just
>about ruled out copper ribbon for various reasons. Ground rods will be 6' or
>deep set on 12' or 16' centers.
>Mike DiGirolamo, W4XN
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