Placement of lightning rods [RE-wrenches]

[Bill Roush, Solar Electric Systems]

I posed some of our lightning questions to Bud VanSickle, from a lightning
rod company in Maryville, MO.  He has grown up in the lightning protection
field and I thought contact with him might be helpful for some of you.  His
email address is included. Bill Roush

 The incorrect statement below is that lightning rods are designed to cause
lightning not
to strike something.  The truth is  the opposite.  Lightning rods are a part
of a passive grounding system, designed to accept a direct lightning strike
and route it harmlessly into the ground.
Obviously, a good grounding system is required.  Everything metallic should
be interconnected with the grounding system to stop lightning side-flashing
by maintaining the lowest ground potential possible.  Some metallic
structures can serve the purpose of intercepting and transferring the
lightning through their construction, and there may be no need for
additional "lightning protection materials" beyond the connection to a good
grounding field or system.
In addition, the comment below about the effects of remote lightning strikes
is correct.  Whether you have a structural l.p. system or not, whether you
have a good ground system or not, lightning will find it's way into the
earth and be picked up by wiring systems run into the structure.  You can
have true voltage spikes, or induced effects which may damage electronic
equipment on or within the structure.  Depending on the nature of the
systems involved, a simple silicon oxide varistor may suffice, or you may
need more sophisticated TVSS sized for panelboards, motors, etc.  The
important thing to remember is that surge suppression only functions as well
as the grounding system that it is attached to (as above), and that
difference of potential must be eliminated on all lines leading to equipment
by connecting through TVSS to the same ground plane.
I am not saying anything a lot different from what is outlined below.  I am
not sure what in our product line might apply, because the problem isn't
really clear to me.  We have products to capture lightning strikes, bond
metal bodies, provide grounding in difficult areas, and a number of surge
suppression items.  We may need to have someone look at the entire problem,
before we would know how to proceed.
Bud

You had , also, sent an additional piece of information regarding a
"dissipation array" product that is advertised to "stop" lightning from
striking by use of multiple needle points.  This would be a great concept if
it worked, but it doesn't seem to work any better than the needles on a pine
tree.  A lightning stroke contains far too much energy to dissipate or
deflect.  It will attach to the best grounded path.  The "dissipation array"
products do provide a grounded path for a lightning strike, but they are
generally excessively expensive.  There really aren't any scientists who do
lightning research who believe that this concept is viable.  There is
someone marketing such a product, and they hired an engineer to write an
IEEE paper about it.  There has been a lot of negative feedback within IEEE
about how that could happen.

It makes a lot more sense to implement good grounding, bonding, and surge
suppression practices, which not only handles direct strike problems, but,
also, can prevent problems with strikes remote to the structure.
Bud

-----Original Message-----
From: Bill Roush [mailto:solarbeacon at email.msn.com]
Sent: Tuesday, February 27, 2001 10:50 AM
To: bvansickle at erico.com
Subject: FW: Placement of lightning rods [RE-wrenches]






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