"Richard Harrison" wrote

Jack Painter wrote:
"Scientists have now shown that blunt-tipped air terminals are attached
by lightning significantly higher frequency than sharp rods are."

I would have expected that sharp-pointed rods would be struck more
often.

Hi Richard, yes, you and Ben Franklin agreed on that. Modeling examples you
cited below appear to be incorrect for lightning, similar to how modeling
for ocean waves cannot be done in a bathtub, and even a swimming pool does
not closely replicate the action of waves in a large body of water. The
experiments and the conclusions offered by the blunt-tip lightning rod tests
were peer reviewed, are repeatable, and are being further studied. Their
conclusions describe behavior that was not expected or explainable by
current modeling. However it is easy to rocket-trigger lightning and this is
being done on a daily basis, so a few thousand repeatable findings should
soon arrive at a more permanent conclusion. Whether or not that is
explainable in terms that classroom scientists can model remains to be seen.
An awful lot of engineers have accepted the findings already, and specify
blunt-tip rods on new construction. The same cannot be said about other
questionable and unrepeatable theory such as charge transfer systems and
lightning charge dissipators. Their popularity relies soley on the ability
of snake-oil salesman conning a confused public.

73,
Jack Painter
Virginia Beach, Virginia



My CRC "Handbook of Chemistry and Physics" starts its coverage of
"Electricity and Magneyism with a page on Spark Gap Voltages. In every
case for a given breakdown voltage, the gap must be substantially wider
when the electrodes are needle-points than when they are spheres. For
example: With a voltage across the electrodes of 5 KV, the gap space
between needle-points needed to prevent a spark is 0.42 cm. The gap
between 5-cm sphheres is 0.15 cm under the same conditions. Much closer
before sparking points obviously means sharp points engourage breakdown
of the air between the points, while spherical (blunt) spark-gap
electrodes discourage the spark.

It`s been said that if the chsrges dont pile op at the pointed end of a
conductor, it would not have an equipotential surface as is required by
the conductivity ("College Physics" by Franklin Miller, Jr.

Best regards, Richard Harrison, KB5WZI

Jack Painter wrote:
"Modeling examples listed below appear to be incorrect for lightning,
similar to how modeling for ocean waves cannot be done in a bathtub and
even a swimming pool does not closely replicate the action of waves in a
large body of water."

OK. Here are full-scale examples. My company had radio towers over much
of the earth. Standard practice was protection of the beacon atop the
tower with a Copperweld ground rod alongside the beacon with its sharp
tip pointed at the sky. No protected beacon was ever damaged by
lightning.

Our company headquarters skyscraper was protected by short air terminals
ringing the perophery of the builsing at short regular intervals. No
lightning damage yet in half a century.

You may say it is squivalent to the fellow who walks into a bar with a
strange contrivance suspended around his neck. Asked what the gadgst
does, the new arrival says: "it`s an elephant whistle". Reply is:
"There`s no elephants around here." New arrival says: "See. It works,
doesn`t it?"

I can assure that there have been plenty of lightning strikes safely
bypassed to ground around the protected people and equipment, just as
Ben Franklin and others have predicted.

Best regards, Richard Harrison, KB5WZI

"Richard Harrison" wrote

Jack Painter wrote:
"Modeling examples listed below appear to be incorrect for lightning,
similar to how modeling for ocean waves cannot be done in a bathtub and
even a swimming pool does not closely replicate the action of waves in a
large body of water."

OK. Here are full-scale examples. My company had radio towers over much
of the earth. Standard practice was protection of the beacon atop the
tower with a Copperweld ground rod alongside the beacon with its sharp
tip pointed at the sky. No protected beacon was ever damaged by
lightning.

Our company headquarters skyscraper was protected by short air terminals
ringing the perophery of the builsing at short regular intervals. No
lightning damage yet in half a century.

You may say it is squivalent to the fellow who walks into a bar with a
strange contrivance suspended around his neck. Asked what the gadgst
does, the new arrival says: "it`s an elephant whistle". Reply is:
"There`s no elephants around here." New arrival says: "See. It works,
doesn`t it?"

I can assure that there have been plenty of lightning strikes safely
bypassed to ground around the protected people and equipment, just as
Ben Franklin and others have predicted.

Best regards, Richard Harrison, KB5WZI


Hi Richard, because it is completely unlike you to so widely miss the point,
I question whether I understood your responses correctly. The standard
Franklin rods (with pointed tips) have been completely validated in their
application of safely terminating lightning strikes. Nothing in the new
study repudiates that in any way. It simply finds that a lightning rod of
similar length, thickness and composition but with a rounded or blunt-tip,
has attached lightning that was coming to it's twenty-odd foot area
everytime and missed the nearby Franklin rods everytime. The study clearly
restates what engineers all over the world already know, that Franklin rods
work just fine. But it ADDS that the blunt-tip rods work better, end of
study.

Because lightning is impossible to predict, and often it strikes areas of a
grounding system and building below the lightning rods (evidence is the
Empire State Bldg, which has video showing dozens of strikes bypassing the
Franklin rods), then if an improved rod-tip design is validated, then it is
validated, simple as that. Your experience describing a pointed tip
protecting a radio tower sounds rather simplistic as examples, don't you
agree? Nothing could be easier than attaching lightning to the top of a
tower for Pete's sake. Where lightning rod placement and design becomes
critical, is in areas such as multi-level/shaped building corners,
appurtenances, high explosive and flammable liquid storage, etc. Here, the
best available science is used to describe how many feet apart, at what
elevations, etc the air terminal system must be in order to achieve the
desired level of confidence that no lightning attachment will cause damage
to structures, materials or personnel.

Happy New Year and best wishes,

Jack Painter
Virginia Beach, Virginia

Jack Painter wrote:
"Modelimg examples cited below appear to be incorrect for lightning,
similar to how modeling for ocean weaves cannot be done in a
bathtub,---."

As far as I know there is one set of rules which rules electrical
phenomena, not rules for weak snd onother set of rules for strong
electricity. Lightning is so stromg that it sometimes seems to play by
its own rules, but it really does not.

Jack`s waves in a bathtub metaphor was particularly ironnic. Franklin`s
experiments proved the electricity he was studying was the same stuff on
whatever scale. He charged Leyden jars from the clouds then used the
stored charge to conduct other experiments with the stored charge as his
contempories were doing. Franklin found that hemp twine was a conductor
of sorts while silk was an insulator.

Irony springs from Jacj`s bathtub metaphor. According to the December
2001 issue of "Modern Maturity":
"Alexander Graham Bell - yes, of telephone fame - also invented the
hydrofoil, a boat that rides on a duchion of air. He tested models of
this invention in his tub."

Best regards, Richard Harrison, KB5WZI

Jack Painter wrote:
"An awful lot of engineers have accepted the findings already, and
specify blunt-tipped rods on new construction.:

They should specify what works.

Suppose a charged cloud arrives overhead and no lightning immediately
flashes. If the charge is positive, it attracts electrons in the earth
ond other conductors nearby. These electrons strain to reach the cloud,
runnibg through conducting bodies to get closer to the positive charges
overhead. The blanket of air insulates between the charges of opposite
polarity. The field grows faster than these charges are neutralized.
Sooner or later, the air at a high point starts to ionize (form a
conductive plazma). Then, current flow starts with a flash and a bang.
Thunder rolls as air rushes in to fill the void left by burnt
atmosphere.

Suppose that a lightning rod is at a high point beneath the positively
charged cloud as it arrives. Electrons are pulled up to its sharp point
(electrons repel each other, ao they tend to concentrate on the outside
of the rod and find the least outside opposing forces at the tip of the
rod.

To avoid corona formation, some transmitting antennas are fitted with
"corona balls" on their tips. This reduces the strain from a pointed
tip.

On a lucky day, the cloud is discharged without lightning. On an ublucky
day, your lightning rod may get pitted.

Best regards, Richard Harrison, KB5WZI

On Thu, 6 Jan 2005 12:21:25 -0600, (Richard
Harrison) wrote:
On a lucky day, the cloud is discharged without lightning. On an ublucky
day, your lightning rod may get pitted.

Hi Richard,

So much of this breathless science of rounded tips alludes to the
legitimacy of rare publications equal in scope and stature to those
that announced the proofs of cold fusion.

Did Pons and Fleishman turn their hands to designing Lightning
protection systems to redeem their credentials?

73's
Richard Clark, KB7QHC

Richard Clark, KB7QHC wrote:
"So much of this breathless science of rounded tips alludes to the
legitimacy of publications equal in scope to those that announced the
proofs of cold fusion."

Well, I`ll give the rounded tips one advantage, less likely impalements
and resulting lawsuits. But, I don`t know of any such cases on the sharp
lightning rods.

As for cold fusion, I`ll believe it when I see it. I really hope it
happens. The price of fossil fuels and their cleanup is excessive.

Best regards, Richard Harrison, KB5WZI

"Richard Clark" wrote

So much of this breathless science of rounded tips alludes to the
legitimacy of rare publications equal in scope and stature to those
that announced the proofs of cold fusion.

Did Pons and Fleishman turn their hands to designing Lightning
protection systems to redeem their credentials?

Interested in your comments *after* you have read the study.
http://lightning-protection-institut...-terminals.pdf

73,
Jack Painter
Virginia Beach, Virginia

On Fri, 7 Jan 2005 01:53:00 -0500, "Jack Painter"
wrote:
Interested in your comments *after* you have read the study.
http://lightning-protection-institut...-terminals.pdf

Hi Jack,

"It is quite obvious from these plots
that the experimentally determined electric field
strength is less than the "simple-minded" V/d value."

Interesting brush-off so early in the paper begs for real editorial
control. As very few would experience lighting sourced from a grid of
wire 5M overhead this paper seems an example of the "laboratory
factor" it set out to examine and yields a paper confined to
laboratory arcana. All fine and well, but what is the point?

"There is an urgent need for detailed theoretical
modelling which can quantify the space charge
effects around air terminals, particularly in
relation to upleader development."

Which seems at odds with your statement:
On Fri, 7 Jan 2005 01:17:07 -0500, "Jack Painter"
wrote:
The junk-science of early-streamer-emission
but I'm not terribly interested. I wasn't particularly intrigued by
Pons and Fleishman either, beyond the hubris of their closet drama.

It would seem some have a desperate need to topple Franklin from a
pedestal of their own building. (Theirs is called the fallacy of
"present mindedness.") I'm satisfied that contemporary Europeans held
him in high esteem for many noble achievements. Reductionists are
measured against their own few of baser metal.

Hope you found that interesting, but I doubt it - rather banal stuff.

73's
Richard Clark, KB7QHC

"Richard Clark" wrote

On Fri, 7 Jan 2005 01:53:00 -0500, "Jack Painter"
wrote:
Interested in your comments *after* you have read the study.
http://lightning-protection-institut...-terminals.pdf

Hi Jack,

"It is quite obvious from these plots
that the experimentally determined electric field
strength is less than the "simple-minded" V/d value."

Interesting brush-off so early in the paper begs for real editorial
control. As very few would experience lighting sourced from a grid of
wire 5M overhead this paper seems an example of the "laboratory
factor" it set out to examine and yields a paper confined to
laboratory arcana. All fine and well, but what is the point?

"There is an urgent need for detailed theoretical
modelling which can quantify the space charge
effects around air terminals, particularly in
relation to upleader development."

Which seems at odds with your statement:
On Fri, 7 Jan 2005 01:17:07 -0500, "Jack Painter"
wrote:
The junk-science of early-streamer-emission
but I'm not terribly interested. I wasn't particularly intrigued by
Pons and Fleishman either, beyond the hubris of their closet drama.

It would seem some have a desperate need to topple Franklin from a
pedestal of their own building. (Theirs is called the fallacy of
"present mindedness.") I'm satisfied that contemporary Europeans held
him in high esteem for many noble achievements. Reductionists are
measured against their own few of baser metal.

Hope you found that interesting, but I doubt it - rather banal stuff.

73's
Richard Clark, KB7QHC

Richard,
Thanks. I always find your comments about scientific material interesting.
There is some monumental evidence accumulating to contest ESE/CTS, and this
begs the question that if there is such a political fight over preventing
its presentation to the whole IEEE body for a vote, what are they so afraid
of? Russian scientists have now been commissioned to find (contrary to all
other studies) that the principle works. Avoiding the comments about
streamers in the referenced paper though, my point really was that they
arrived at a statistical average they may have been looking for, but
attempts to remove the laboratory principle appeared honest to me (and to
others). Your opinion there is important, at least to me.

73,
Jack Painter
Virginia Beach, VA