[TowerTalk] Static, Lightening, and protection

[David Robbins K1TTT]

> 
> The "rules" seem to be like this:
> If you want to create "umbrella lightning repellent" protection
situation,
> the tower should be as high as possible. Roughly it will protect
> hemisphere with
> radius of the tower.

The more common 'rule' is that a tower will protect a circle roughly
equal to its height by attracting lightning to itself from the area.
Larger or smaller distances are claimed by some authors.  The effect is
dependent on total height and the peak stroke current among other
variables.  Low current strokes are known to 'sneak' in the sides and
actually hit the sides of buildings and towers instead of the top.  This
is because the streamers from the ground structures are shorter and the
attraction of the opposite charges on the structure pulls the leader
closer as it comes down.  High current strokes are less affected by the
structures and the streamers are much longer going up to meet the
leader.


David Robbins K1TTT
e-mail: mailto:k1ttt at arrl.net
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