Most experts (?) agree that one should run a ground
jumper wire from the mast to a tower leg before the
rotator so that strike energy does not go through the
rotator and possibly welding the bearings to the bearing
race. Personally I used #4 welding cable which had many
small wires for low impedance path and high current
carrying capability. (Some experts suggest ground braid
whilst others warn against it due to corrosion between
the exposed braid wires causing increased impedance
and/or diode effects.) I connected it from the top bolt
on the rotator's mast clamp to a predrilled hole in the
nearby tower leg. I wrapped the welding cable's rubber
jacket with electrical tape to protect against UV
degradation. Phil KB9CRY
> Typical installations place a mast above the tower, mounted to a rotator
> and in a bearing at the top of the tower. These connections to the
> tower are through bearings, which puts the bearings at some risk if the
> mast takes a lightning stroke. Transmission lines from any antennae on
> the mast provide parallel conductive paths to the tower and to the
> ground system.
>
> Is this a problem?
>
>
> What are some additional ways to ground the mast? What if the mast and
> tower are both aluminum?
>
> 73 de WO0W
>
>
>
>
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