The phenomena is well understood ... by a few. The major cause of damage
from
lightning is due to acoustics. (a/k/a ... thunder). In this case the
insulators have
suffered environmental fissures/cracks and along comes a strike that arcs
across the insulators ... some of that arc finds its way along the internal
cracks
and the resulting internal acoustical pressure is HUGE ... and POW, the
insulator is fragmented.
That simple. de dave w7fb
-----Original Message-----
From: Cqtestk4xs+AEA-aol.com +ADw-Cqtestk4xs+AEA-aol.com+AD4-
To: TOWERTALK+AEA-contesting.com +ADw-TOWERTALK+AEA-contesting.com+AD4-
Date: Thursday, October 23, 2003 4:03 PM
Subject: Re: +AFs-TowerTalk+AF0- Broken Johnny-ball insulators
+AD4-I have taken a number of hits on my towers over the last few years since
+AD4-1998. I have seen firsthand as the lightning hit the towers during
thunderstorms.
+AD4- Fortunately, most of the hits have gone down to earth.
+AD4-
+AD4-Most of the guy wires on the towers are Phillystran, but on the 40 meter
+AD4-tower I had some EHS guy material left over and had to 'piece together' two
pieces
+AD4-to make the 250 foot guy wire run. It is on those insulators that the
+AD4-cracking and arcing took place. I have heard tales of people hearing
snapping and
+AD4-popping at the insulators as storms approach on broadcast towers. I would
+AD4-imagine it happens on a grander scale from a lightning hit on the tower.
Perhaps
+AD4-multiple hits over a period of time, especially in lightning prone areas,
+AD4-could cause the damage as N4ZR and I have observed.
+AD4-
+AD4-Those of you in the lightning prone areas might want to get out the
+AD4-binoculars to take a peak at those ceramic insulators used to break up the
guy wire.
+AD4-
+AD4-Bill K4XS
+AD4AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBf-
+AD4-
+AD4-See: http://www.mscomputer.com for +ACI-Self Supporting Towers+ACI-,
+ACI-Wireless
Weather Stations+ACI-, and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
+AD4-
+AD4AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBfAF8AXwBf-
+AD4-TowerTalk mailing list
+AD4-TowerTalk+AEA-contesting.com
+AD4-http://lists.contesting.com/mailman/listinfo/towertalk
+AD4-
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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