w_tom wrote:

Michael Terrell cries, "Woe is me. Nothing can prevent
lightning damage." Meanwhile professionals learn from human
mistakes and routinely prevent lightning damage:
Richard Harrison posts on 7 May 2001 in the newsgroup
rec.radio.amateur.antenna entitled "Grounding Question -
Connecting to Power Ground":
Early in 1949 I started work in broadcasting. I worked in three
stations in that year, KPRC, KXYZ, and KTHT. The first two were
built in the 1930`s and KTHT was about one year old when I went
to work there in 1949.

None of these stations ever suffered lightning damage when
taking many direct hits during every year. In fact they only
dropped from the air for an instant, to extinguish any
follow-through arcing when hit, and were returned to the air
automatically following an arc kill.

In 1949 there were already thousands of AM broadcast stations.
Some were improperly protected against lightninmg, but the vast
majority, like the stations I worked at, were almost perfectly
protected against lightning damage, and so it was almost
unheard of.

Ben Franklin figured how to protect structures against lightning
over 200 years ago. The rest is just elaboration.


Poor ole Ben got SOME things right. Others were as wrong as you
are. Early lightning rods caused damage because they didn't understand
how they really worked, or how to properly install them. Have you ever
seen an old building burn down after lightning hit the old "Franklin
Style" lightning rods? Have you seen the way the sections were
connected together with no consideration of minimizing and maintaining a
very low resistance at each connection? The heavy twisted braid used
where the rod across the roof tuned sharply to go down the side of the
building? Yes sir! Ole Ben sure know how to attract lightning and that
was all. The rest of the system was a hack.

Or http://www.harvardrepeater.org/news/lightning.html
Well I assert, from personal and broadcast experience spanning
30 years, that you can design a system that will handle *direct
lightning strikes* on a routine basis. It takes some planning
and careful layout, but it's not hard, nor is it overly
expensive. At WXIA-TV, my other job, we take direct lightning
strikes nearly every time there's a thunderstorm. Our downtime
from such strikes is almost non-existant. The last time we
went down from a strike, it was due to a strike on the power
company's lines knocking *them* out, ...

A TV tower is fully grounded, and generally heavier than an AM radio
tower which is insulated from ground and depends on a pair of large
balls to make the lightning arc to ground. I used to have what was left
of a set that was hit too many times and shattered.

Since my disasterous strike, I've been campaigning vigorously
to educate amateurs that you *can* avoid damage from direct
strikes. The belief that there's no protection from direct
strike damage is *myth*. ...
The keys to effective lightning protection are surprisingly
simple, and surprisingly less than obvious. Of course you
*must* have a single point ground system that eliminates all
ground loops. And you must present a low *impedance* path for
the energy to go. That's most generally a low *inductance*
path rather than just a low ohm DC path.

And even from Sun Microsystems "Planning guide for Sun
Server room":
http://www.sun.com/servers/white-pap...ning-guide.pdf
Lightning surges cannot be stopped, but they can be diverted.
The plans for the data center should be thoroughly reviewed
to identify any paths for surge entry into the data center.
Surge arrestors can be designed into the system to help
mitigate the potential for lightning damage within the data
center. These should divert the power of the surge by
providing a path to ground for the surge energy.

Did Michael Terrell cite technical facts? Of course not.
Others here have posted how damage is routinely avoided.
Thank you Michael for your insults. When do you provide a
single reason why this well proven science does not work? Its
been a few years. When do you provide one good technical
reason?

I have cited a lot of things in the past, and you've always ignored
them. You've been spreading the party line of lies for years, ignoring
every statement and reference.

Here you are parroting other people's data. You did not do the
research, or the actual work. I'm surprised you didn't toss in "The
Empire State building" as usual. You refuse to accept that grounding
systems deteriorate with age, or can be damaged. WLBE in Lake County
Florida lost most of their antenna grounding system when a mall was
built next door. The workers crossed the property line with a bulldozer
and ripped out half of the buried 4" copper strapping. The antennas sit
on two platforms in a marsh and can be hit repeatedly during a single
storm. In fact, it doesn't even have to storm to see and hear the bolt
strike one, or both towers. Over time something fails. I asked the
engineer to go on line and tell you himself but Frank simply laughed and
said that you were too damn stupid to know what he was talking about. I
think he's right. You've never worked here in Florida, or seen the
damage caused by repeated strikes on a single structure in a short time
frame. Pieces of steel warped from the high current flow, or other
equipment damaged by induced current from the EMP. You are a troll. On
the atomic chart you would be Hydrogen. You are stupid, pig headed, and
a pimple on the ass of Usenet. You only care about pushing your
harebrained agenda. You refuse to listen to those with experience.


Yes there are things that can be done to reduce lightning damage.
Yes, systems fail. Nothing man-made is perfect, nor will it ever be. As
long as you keep spreading your lies and half truths, people will call
you on it. You are not only stupid, you're dangerous.

Others who learned from lightning damage eliminate a failure
rather than just replace electronics. Michael endorses
failure as if it was situation normal. Even children are
taught not to be quitters. Damage from direct lightning
strikes is routinely avoided.


I have tried several times in the past to explain induced secondary
damage, but it bounces right off your thick skull. It doesn't fit your
agenda so you ignore it.

So which week was Michael's town without phone service while
the telco switching computer was replaced? Oh? They don't
disconnect that computer from overhead wires everywhere in
town during thunderstorms? How can that be when Michael says
protection is not effective?


Once again, you are telling a big ole pack of lies. I stated that a
pair in a buried line from my house to the equipment pedestal a mile
away was vaporized, that the cards on that line were fried, and that the
pair from the equipment pedestal to the CO was damaged so bad they had
to abandon it, and replace the interface card at the CO. You are as
dense as the operator at Sprint who had to yell over the static on the
damaged pair to ask "Are you sure there is something wrong with your
telephone service?". It is you that spreads the lie that telephone
equipment is never damaged by lightning.

I never said the whole town was without phone service. On the other
hand, one whole exchange (10,000 phone numbers) was out of service for
about 24 hours back in the '80s after a storm. The contractor didn't
assemble the buss bars properly, a pinhole leak dripped into the buss
duct and it exploded. The idiots had assembled the buss bars with zinc
plated bolts and the damage was so bad they had to replace most of the
buss bars, and replace the zinc plated steel bolts with the proper brass
bolts.


--
Former professional electron wrangler.

Michael A. Terrell
Central Florida