Surge / Ground / Lightning

[Guest]

| "Tony Hwang" wrote:
|> You seem to be confused between current flow(energy) and voltage(poential)
|> Nothing flows in an open circuit. If not we
|> have to rewrite Ohm's law. Show your credential to make a
|> stamement like that.
|
|
| You're forgetting RF frequencies - which can flow (back
| and forth) quite readily in an open circuit such as a transmitter
| tower, whip antenna, or transmission line, or building power
| wiring, steel frame, etc.

I think they intentionally ignored it. Well, maybe Mr. Terrell actually
forgot.

 

[Guest]

| |> | |> |> |
|> |> |
|> |> |>Maybe he taken a hiatus after the right propper whopping he got here
|> |> |>last week. I thought it was hillarious after he derided the makers
|> |> |>of plug-in surge protectors and then gave us his list of "real
|> |> |>companies", like Intermatic, GE, Leviton, etc., that were experts at
|> |> |>it. Only problem was, all of the companies on his list sell
|> plug-in
|> |> |>ones too.
|> |> |
|> |> | Huh, so according to all of w_'s sermons, Bud must be working
|> overtime
|> |> as a
|> |> | salesman for all of those companies too? Busy guy!
|> |>
|> |> Both do not appear to be wrong to me. They appear more to be arguing
|> |> about
|> |> entirely different issues. But I can't be entirely sure because their
|> |> rants
|> |> are hard to read and I skip a lot of it, including any post where the
|> |> first
|> |> screenful is all quoted text. And my googlegroups filter is killing
|> off
|> |> the
|> |> posts from w_tom that don't have any threading where I have posted.
|> |
|> | Is googlegroups filtering possible using Outlook Express?
|>
|> Not that I know of. But my reader is configured to filter out
|> Googlegroups
|> due to Google's lack of action to deal with the massive spam floods they
|> let
|> reach Usenet. Not only is there many times as much spam from Googlegroups
|> as legitimate posts in the groups I read, but in many, the level of normal
|> posts has fallen, suggesting that this issue is causing some to abandon
|> Usenet
|> because of this.
|
| Thanks for the info.

I should clarify that where I said "many times as much spam from Googlegroups
as legitimate posts in the groups I read" I was referring to legitimate posts
ALSO FROM Googlegroups (the ones I would lose by blocking). In some cases the
spam truly was in excess of ALL legitimate posts. As it turns out, my newsreader
will still show the killed posts with a "K" in the threading displays. So if
someone followed them, or they followed one of mine, I can at least pick it.
But the normal tabbing through new posts still skips them.

 

[Leonard Caillouet]

In alt.tv.tech.hdtv Franc Zabkar <[email protected]> wrote:

The MOVs will act like conductors when they are clamping. The surge will
take both paths ... the path through the MOVs, and the path going past the
MOVs. In general, about 50% will go each way. That can vary at higher
frequencies.

Why would you assume that 50% will go each way when you don't know the
impedance of each direction? When conducting, or at failure, the MOV has a
very low impedance.

Leonard

 

[Tony Hwang]

Who knows? Wherever he came from, I don't see him on this computer.
All I know is that I finally kill filed him on this computer after I got
tired of reading his 'twilight zone' electrical & electronics babble. I
am a former radio & TV broadcast engineer, and if I followed his or
_wacko_tom's warped ideas, I would have had millions of dollars worth of
damage. I had a studio building and STL tower in Leesburg Florida hit
by a direct strike. It blew chunks of concrete from the building where
the rebar and threaded rods ran vertical. It WAS an excellent example
of _wacko_tom's UFER ground, before the steel vaporized inside damp
concrete. 95% of the damage was caused by the EMP. I lost the 11 GHz
Cars band STL, the 1A2 type phone system, all the computer terminals,
and had some minor problems with other electronics. It turned out that
the dead terminals all had high ESR electrolytics, and that they were
working because they were all on UPS before the strike took out all the
electricity. The power 1A2 supply needed some of the weird WE fuses,
one KTU card and was back in service. The STL was mounted on the tower
in a steel NEMA box, and lost the LO module. It was 20 years old, and
at least 10 years obsolete, so it needed that module updated, anyway.

I started with the phones, then arranged a twice a day courier form
the studio to the transmitter site with U-matic tapes. We rented a STL
transmitter and shipped the damaged system to the OEM for repair &
upgrading. The terminals were down for a day, while I waited for the
new electrolytics. Or viewers didn't even know we had been hit. Then I
moved the microwave racks to a closet in the corner of the building, and
used 4" EMT between the rack and the tower. That was 20 years ago. They
have had strikes since then, but no problems.

Hi,
Qucik check on Buckmaster shows he was born in '55. Technician
plus(novice) holder. For his age, does not seem to have corresponding
wisdom.

 

[Tony Hwang]

| (e-mail address removed) wrote:
|>
|>
|> | Bullshit. Like ALL charges, it simply seeks a complete circuit to
|> | flow. You have absolutely no grasp of the basic concepts, yet you
|> | continue to spout your ignorance and lies.
|>
|> Not true.
|>
|> When you close a switch between a power source and a pair of wires that go
|> out yonder, the electrical energy does not "know" whether the circuit is
|> complete or not. If it refused to flow, it would not be able to find out.
|> It will flow, whether the circuit is complete or not. What happens after
|> that depends on what is at the other end, which could be an open condition,
|> a short circuit, or some kind of resistive or reactive load.
|>
|> You've claimed to have worked in broadcasting in an engineering role. So
|> you should understand what happens at the end of an open transmission line.
|> The electricity flows to get to the open end. Yet it is not a "complete
|> circuit".
|
|
| Yawn. You are trying your usual lame crap of misdirection.
| Electromotive force and electromagnetic waves are not the same. you
| claim to be an amateur radio operator, so you SHOULD know the
| difference.

1. I *am* an amateur radio operator and I *do* know the difference.

2. Electromotive force is not a factor here, beyond what it might do to cause
physical motion of wires during a surge (not impossible, but not usually
considered).

Hmmm,
Lenz and Hertz?

 

[Tony Hwang]

| (e-mail address removed) wrote:
|>
|> | Bullshit. Like ALL charges, it simply seeks a complete circuit to
|> | flow. You have absolutely no grasp of the basic concepts, yet you
|> | continue to spout your ignorance and lies.
|>
|> Not true.
|>
|> When you close a switch between a power source and a pair of wires that go
|> out yonder, the electrical energy does not "know" whether the circuit is
|> complete or not. If it refused to flow, it would not be able to find out.
|> It will flow, whether the circuit is complete or not. What happens after
|> that depends on what is at the other end, which could be an open condition,
|> a short circuit, or some kind of resistive or reactive load.
|>
|> You've claimed to have worked in broadcasting in an engineering role. So
|> you should understand what happens at the end of an open transmission line.
|> The electricity flows to get to the open end. Yet it is not a "complete
|> circuit".
|>
| Hmmm,
| You seem to be confused between current flow(energy) and
| voltage(poential) Nothing flows in an open circuit. If not we have to
| rewrite Ohm's law. Show your credential to make a stamement like that.
| Shameful.

Your knowledge of electricity shows to be a very basic level. You completely
lack an understanding of how electricity does flow. You have no concept at all
of transmission lines (and Michael A. Terrell seems to have forgotten his).
Credentials have nothing to do with whether a statement is correct or not.
Mine is correct but you don't have sufficient background to even understand it.

Plonk!!!!!!!!!!!!!

 

[Guest]

| |
|>
|> The MOVs will act like conductors when they are clamping. The surge will
|> take both paths ... the path through the MOVs, and the path going past the
|> MOVs. In general, about 50% will go each way. That can vary at higher
|> frequencies.
|
| Why would you assume that 50% will go each way when you don't know the
| impedance of each direction? When conducting, or at failure, the MOV has a
| very low impedance.

There is a distinction between "go each way" and "what comes back" due to
the impedance. It will be about 50% that goes each way _because_ the power
itself does not (yet) know the impedance (at a distance), until it gets
there.

There are two kinds of impedance to deal with here. The first (literally)
is the characteristic impedance. At the point of the MOVs themselves, it
will be about the same each way, but it can vary some at higher frequencies.
It depends on the way the MOVs and the connections with them are constructed.

The second is the net impedance of the path beyond the MOV connections.
That impedance is not what I am talking about in my prior statement. Yes,
it plays a part, but it is not infliienced by the MOVs. It would be the
same if you simply shorted the MOVs with a wire (though that certainly
causes other things to not work, so that isn't how protection is done).

Ultimately you do have to consider the _whole_ system to get an accurate view
of exactly what will happen. Generally this is impractical. What you have
to do is understand what can happen with the variations, and try to change
things to make the happenings do what you prefer (e.g. avoid damage to the
protected devices).

One example involved the power wiring. There should be a point where you
have the neutral grounded, and heavy duty MOVs between each hot wire (be
that 1, 2 or 3) and the grounded wire, and between individual hot wires as
well. The grounded wire (referred to as neutral, but incorrectly in some
cases, even though this is the common referral) would be directly connected
to the path to ground. That connection should be with the least impedance
you can possibly get, within your cost/risk criteria. That means a short
and/or heavy conductor. Short to make it more effective at higher frequencies
by reducing inductive impedance. Heavy to handle a greater current flow.
Much of the surge can now take this path to ground. But not all of it will.
To maximize what will take the path to ground, and minimize what goes to the
building loads/devices that could be damaged, you need to have an increased
impedance on that path. Clearly resistors are not workable since that stops
the power itself, which you do not want to impede. What can work is a low
pass filter primarily an inductor. It needs to be made to have very little
effect at 60 Hz and below, yet block energy/power above that as much as is
possible (again, within your cost/risk criteria). The combination of these
things can limit the surge that reaches protected devices to a tiny fraction
of its original energy.

 

[Guest]

| (e-mail address removed) wrote:
|>
|> | Would you please sum up what you believe to be prudent
|> | protection (for electronic equipment) from nearby lightning strikes?
|> | I'm thinking of both in single-family homes and in condo/apartment
|> | buildings. What would you do to protect from in-house (or in-building)
|> | surges, such as elevator motors suddenly shorting out, or welding
|> | equipment in use?
|>
|> How much money are you willing to spend?
|>
|
| The only thing I can think of that comes close is to have a heavy
| motor/generator set with a HUGE flywheel sitting in the basement.

How about driving a generator in the basement with either a heavy fiberglass
axle rod driven at some distance by a (sacrificial) motor, or by a fluid that
does not conduct electricity through a turbine system, similarly driven by a
motor/pump at some distance.

 

[Guest]

| Michael A. Terrell wrote:
|
|> Tony Hwang wrote:
|>
|>>Hmmm,
|>>Prpbably wannabee ham came from CB crowd when Morse code requirement was
|>>dropped.
|>
|>
|>
|> Who knows? Wherever he came from, I don't see him on this computer.
|> All I know is that I finally kill filed him on this computer after I got
|> tired of reading his 'twilight zone' electrical & electronics babble. I
|> am a former radio & TV broadcast engineer, and if I followed his or
|> _wacko_tom's warped ideas, I would have had millions of dollars worth of
|> damage. I had a studio building and STL tower in Leesburg Florida hit
|> by a direct strike. It blew chunks of concrete from the building where
|> the rebar and threaded rods ran vertical. It WAS an excellent example
|> of _wacko_tom's UFER ground, before the steel vaporized inside damp
|> concrete. 95% of the damage was caused by the EMP. I lost the 11 GHz
|> Cars band STL, the 1A2 type phone system, all the computer terminals,
|> and had some minor problems with other electronics. It turned out that
|> the dead terminals all had high ESR electrolytics, and that they were
|> working because they were all on UPS before the strike took out all the
|> electricity. The power 1A2 supply needed some of the weird WE fuses,
|> one KTU card and was back in service. The STL was mounted on the tower
|> in a steel NEMA box, and lost the LO module. It was 20 years old, and
|> at least 10 years obsolete, so it needed that module updated, anyway.
|>
|> I started with the phones, then arranged a twice a day courier form
|> the studio to the transmitter site with U-matic tapes. We rented a STL
|> transmitter and shipped the damaged system to the OEM for repair &
|> upgrading. The terminals were down for a day, while I waited for the
|> new electrolytics. Or viewers didn't even know we had been hit. Then I
|> moved the microwave racks to a closet in the corner of the building, and
|> used 4" EMT between the rack and the tower. That was 20 years ago. They
|> have had strikes since then, but no problems.
|>
|>
| Hi,
| Qucik check on Buckmaster shows he was born in '55. Technician
| plus(novice) holder. For his age, does not seem to have corresponding
| wisdom.

Whose wisdom are you judging? What have you see that I have posted that you
think is wrong? Would you like to debate the technical points? Or do you
just want to be one of those people that can only "win" by making personal
attacks?

 

[Guest]

| (e-mail address removed) wrote:
|
|> | (e-mail address removed) wrote:
|> |>
|> |>
|> |> | Bullshit. Like ALL charges, it simply seeks a complete circuit to
|> |> | flow. You have absolutely no grasp of the basic concepts, yet you
|> |> | continue to spout your ignorance and lies.
|> |>
|> |> Not true.
|> |>
|> |> When you close a switch between a power source and a pair of wires that go
|> |> out yonder, the electrical energy does not "know" whether the circuit is
|> |> complete or not. If it refused to flow, it would not be able to find out.
|> |> It will flow, whether the circuit is complete or not. What happens after
|> |> that depends on what is at the other end, which could be an open condition,
|> |> a short circuit, or some kind of resistive or reactive load.
|> |>
|> |> You've claimed to have worked in broadcasting in an engineering role. So
|> |> you should understand what happens at the end of an open transmission line.
|> |> The electricity flows to get to the open end. Yet it is not a "complete
|> |> circuit".
|> |
|> |
|> | Yawn. You are trying your usual lame crap of misdirection.
|> | Electromotive force and electromagnetic waves are not the same. you
|> | claim to be an amateur radio operator, so you SHOULD know the
|> | difference.
|>
|> 1. I *am* an amateur radio operator and I *do* know the difference.
|>
|> 2. Electromotive force is not a factor here, beyond what it might do to cause
|> physical motion of wires during a surge (not impossible, but not usually
|> considered).

Things like motors and generators, including Faraday's homopolar generator,
are interesting things to talk about (IMHO) ... in a different thread. Bring
it up (post a new thread) if you have a point to say or a question to ask.
It should generally go in alt.engineering.electrical, only, not the many other
groups that have been put in this thread.

 

[Guest]

| (e-mail address removed) wrote:
|
|> | (e-mail address removed) wrote:
|> |>
|> |> | Bullshit. Like ALL charges, it simply seeks a complete circuit to
|> |> | flow. You have absolutely no grasp of the basic concepts, yet you
|> |> | continue to spout your ignorance and lies.
|> |>
|> |> Not true.
|> |>
|> |> When you close a switch between a power source and a pair of wires that go
|> |> out yonder, the electrical energy does not "know" whether the circuit is
|> |> complete or not. If it refused to flow, it would not be able to find out.
|> |> It will flow, whether the circuit is complete or not. What happens after
|> |> that depends on what is at the other end, which could be an open condition,
|> |> a short circuit, or some kind of resistive or reactive load.
|> |>
|> |> You've claimed to have worked in broadcasting in an engineering role. So
|> |> you should understand what happens at the end of an open transmission line.
|> |> The electricity flows to get to the open end. Yet it is not a "complete
|> |> circuit".
|> |>
|> | Hmmm,
|> | You seem to be confused between current flow(energy) and
|> | voltage(poential) Nothing flows in an open circuit. If not we have to
|> | rewrite Ohm's law. Show your credential to make a stamement like that.
|> | Shameful.
|>
|> Your knowledge of electricity shows to be a very basic level. You completely
|> lack an understanding of how electricity does flow. You have no concept at all
|> of transmission lines (and Michael A. Terrell seems to have forgotten his).
|> Credentials have nothing to do with whether a statement is correct or not.
|> Mine is correct but you don't have sufficient background to even understand it.
|>
| Plonk!!!!!!!!!!!!!

Bye. Nothing missed. Nothing gained.

 

[Guest]

| (e-mail address removed) wrote:
|>
|> | Actually, a real current will flow until the line's capacitance is
|> | charged to the source voltage. When the source is removed, the energy
|> | involved will remain until it is leaked off through the inter-wire
|> | resistance. If the source is AC, no net energy will "flow", except that
|> | lost in the inter-wire resistance. If the line length is long enough at
|> | the frequency involved, reflections from the end of an incorrectly
|> | terminated transmission line will return to dissipate energy in the
|> | source resistance.
|>
|> That reflection even happens with DC. When the switch closes, you have a
|> rising wavefront leading the chargeup of the line. Unless the far end has
|> a perfectly matched load, that wavefront will reflect back. This is in
|> fact how a lot of very early radio transmissions were tuned, with the
|> "switch" being a noisy spark gap, and the "line" being a long wire antenna
|> cut to a specific length. You don't even need to have 2 conductors.
|
| That's because a switch closure is not really DC. Resolve a step
| function into a Fourier series, and it has an infinite number of AC
| components. In the case of a single wire, you do need to consider EM
| theory.

Electromagnetic, yes. Electromotive (as someone else suggested), not really.

 

[bud--]

| (e-mail address removed) wrote:

|> | You suggest experts in the field "missed a lot of reality" and "flubbed
|> | the experiment".
|>
|> I propose that as one explanation as to why these guides come up short on
|> the explanations.
|
| Translation - they don't say what you believe. They "missed a lot of
| reality" was in response to one of your beliefs that is not found in any
| of the rather extensive reading I have done. And another of your beliefs
| for which you have no supporting cite.

You are likely to never see any citation that attests to what I believe.

Because some of what you believe has nothing to do with the real world.

| And you are again discounting a guide written by experts, peer reviewed
| by experts, published by the IEEE, and aimed at technical people. You
| apparently think electrical engineers are idiots. Where you disagree
| with the guide you have not cited a source that supports your belief.

I've _met_ electrical engineers that are idiots. I've met people in a
lot of other fields that are idiots.

I don't know if the authors of what you have read are idiots. Maybe they
are just not writing as broadly as you think they are.

Of course they are idiots. They are all members of the IEEE. Only idiots
can join. And only the biggest idiots can write publications for the IEEE.

Martzloff is not only an IEEE idiot. He worked for the NIST - another
well known lair of idiots.

Thank goodness you aren’t a member.

|> For example, consider the high frequency issue. High frequency energy is
|> less common than low frequency energy. Partly this is because the chance
|> of a closer lightning strike is less than a more distant one. A strike
|> within 100 meters is only 1/8 as like as a strike outside of 100 meters
|> but within 300 meters. Some people then feel that they can dismiss high
|> frequency energy issues entirely.
|
| Francois Martzloff was the surge guru at the NIST and has many published
| papers on surges and suppression. In one of them he wrote:
| "From this first test, we can draw the conclusion (predictable, but too
| often not recognized in qualitative discussions of reflections in wiring
| systems) that it is not appropriate to apply classical transmission line
| concepts to wiring systems if the front of the wave is not shorter than
| the travel time of the impulse. For a 1.2/50 us impulse, this means that
| the line must be at least 200 m long before one can think in terms of
| classical transmission line behavior."
| Residential branch circuits aren't 200m.
|
| Your response: "Then he flubbed the experiment." In another case you
| have said Martzloff had a hidden agenda.

I addressed this one elsewhere. You seem to have misunderstood him.
He did not say that wiring systems do not exhibit transmission line
characteristics.

If you had actually read the quote:
"*it is not appropriate to apply classical transmission line concepts to
wiring systems*"
and "*this means that the line must be at least 200 m long before one
can think in terms of classical transmission line behavior*."

Repeating: "Residential branch circuits aren't 200m."

Rather, he points out that one does not need to look
at the transmission line characteristics in certain cases.

Like branch circuits under 200 meters long.

| You claim lightning induced surges have rise times about a thousand
| times faster than accepted IEEE standards - which are experimentally
| derived.

So you are narrowing this statement to only induced surges?

I intended "induced" meaning produced by including the most damaging -
strikes to utility lines.

I didn't see where you quoted anything by IEEE or its experts that specify
actual rise times of any kind of surge, induced or otherwise.

From the Martzloff quote you didn't read:
"For a 1.2/50 us impulse". That is 1.2 microseconds rise time.

From w_'s favorite engineer source "an 8 microsecond rise time".

Don’t you read anything?

The numbers come from an IEEE standard - accepted by everyone but you.

| One of w_'s favorite professional engineer sources says an 8 microsecond
| rise time for a lightning induced surge is a "representative pulse",
| with most of the spectrum under 100kHz. You don?t get transmission line
| effects at 100kHz.

I agree that you don't get transmission line effects under 100 kHz for 200m
wires ... of any significance to worry about for surge matters.

OTOH, you have not shown how even if an 8 microsecond rise time is significant
as a representative case, that it can't get shorter than that in severe cases.
or even a higher rise voltage (which hasn't even been specified at all here).

I provided 2 direct sources. They follow IEEE standards for rise time.

Still never seen - a cite that supports your opinion.
It is Phil’s phantasy physics.

 

[w_tom]

OK, thanks. That all makes sense. However, I was thinking of a typical
2-pin TV, not an earthed computer.

Black AC wire surge is now shunted (clamped, diverted) to white
wire. Surge now has two paths to obtain earth ground via the TV.

One most common path to ground is TV's cable. Why? Cable TV is now
properly installed - connected (bonded) typically 'less than 10 feet'
to earth ground at the service entrance. If an AC line surge is
earthed at that same service entrance using the single point earth
ground, then no destructive surge circuit exists through that two wire
TV.

But the home owner believed myths of plug-in protectors instead of
learning why earthing (and 'whole house' protectors) is so important.
Whereas surge on cable TV is dissipated in earth, simultaneous surge
on AC electric arrives at an adjacent protector, is shunted to white
(neutral) AC wire, and now has two destructive paths via that TV to
earth ground. Eliminate the plug-in protector to have only one
potentially destructive incoming path (increased protection). Or
properly earth a 'whole house' protector to have zero potentially
destructive paths.

 

[bud--]

| As always, "w_tom" ignores that the high voltages that short out
| "3 miles of sky" will short out the underground power lines which
| enter my building and buildings all over America. Anything able to
| leap "3 miles of sky" will leap the fraction of an inch between the
| power lines and the earthed metal conduit. What is left will be a
| much lower voltage spike that can be handled by the average
| "plug-in protector".

It does not always make the 2nd leap to ground. There is not always a metal
conduit available. I've seen such strikes.

With no service panel suppressor it is well accepted that at about 6kV
there will be arc-over from bus to enclosure for (US) circuit breaker
panels. While arcing, the voltage will be hundreds of volts. Since the
panel/system ground is connected to the earth electrode (US) most of
surge energy is dumped to earth.

If talking about a plug-in suppressor, Experiments by Martzloff (the
idiot/member-of-the-IEEE) show surprisingly little energy reaches the
suppressor. Circuit impedance greatly limits the current, and thus
energy. Surprisingly, there is more energy at the MOV for lower surge
currents (on short branch circuits) because the MOV can hold the panel
voltage below the 6kV breakover voltage. With up to 10kA surges, the max
energy at the MOV was 34J with most cases below 1.2J.

 

[w_tom]

I experienced a direct lightning strike on a 7 story building. In the
basement there was a large(I mean LARGE) scale data center which I was
in charge of.
The strike clobbered all the data stored in mass storage sub system
requiring 3 days' total system restore. I think when surge is BIG,
nothing can be protected from it.

Broadcasting electronics atop the Empire State Building and World
Trade Center were struck 25 and 40 times annually without damage.
Commercial broadcasters with antennas thousands of feet up also suffer
such strikes and cannot suffer damage. Your telco with switching
centers in every town; with their $multi-million switching computer
connected to overhead wires all over town; must suffer such surges
routinely without damage. Mid 1900 research indicates a thunderstorm
typically creates maybe 100 surges - and no damage.

Likely the outgoing path through that scale was via concrete floor.
What was the incoming path? Well what in that circuit was damaged?
Or was it only data loss, which means hardware protected itself when
too much surge current was permitted inside the building?

How many days did your telco require to reprogram that switching
center computer after every thunderstorm? They can suffer 100 surges
during every thunderstorm and not even suffer data loss - let alone
hardware damage? Exactly. Effective protection means every wire in
every incoming cable has a short connection to earth via a 'whole
house' protector AND separation of up to 50 meters between the
protector and electronics. Not used are plug-in protectors. Any
protection that would work at the equipment is already inside the
equipment. Not acceptable is damage from lightning – even data loss.
And if damage does occur, telco located and corrected an earthing
defect.

Another example in Central Florida where Orange County's emergency
response system suffered lightning damage. Lightning damage
eliminated by fixing the defect - earthing:
http://www.psihq.com/AllCopper.htm

Same is described by van Deursen and van der Laan when lightning
caused damage to a nuclear hardened maritime radio station. Did they
cry, "Woe is me. Nothing can stop lightning damage"? Of course not.
Their IEEE paper describes how earthing defects (human failures) were
fixed. Lightning damage directly traceable to a defect in the
earthing system – human failure.

It is routine to suffer even the most massive surges and no surge
damage. Lightning routinely strikes communication facilities on Hoher
Peissenberg mountain in southern Germany - without damage.
Researchers even mounted electronics equipment to measure the currents
of each surge. Did direct lightning strike destroy that electronics
and communication equipment? Or course not. It is routine to suffer
direct strikes without electronics damage. However the human must
first learn what provides that protection - especially proper
connections to earth ground.

What makes surge protection so challenging? We can test other
designs. But we cannot test the surge protection system. Therefore,
when damage does occur, the responsible human locates and learns his
mistake - often must correct a defective in that earthing system.
Numerous professional citations also describe learning from the damage
because lightning damage is so easily avoid.

A protector is only as effective as its earth ground. As Phil
correctly notes:

But it is a matter of how much you want to spend on it.

Simple earthing to meet NEC requirements creates significant
protection. High reliability facilities may spend even hundreds more
to obtain but a little more protection. On average, a destructive
surge may occur once every seven years. How much would you spend.
$20 for some earthing rods to significantly upgrade protection; or
$hundreds to also have protection installed in Central Florida:
http://members.aol.com/gfretwell/ufer.jpg
How much was that data worth? A question asked of others since Tony
Hwang routinely denies this stuff. He suffered massive station
damage. Then he declared nothing can protect from lightning even
though his industry peers says completely otherwise.

 

[bud--]

See many posts that describe this same failure to a network of
powered off computers. Surge incoming on wires that typically carry
most surges into buildings: black (hot) AC wire. Surge arrived two
plug-in protectors - each adjacent to powered off computers. Often
that surge is trivial; does not overwhelm protection inside a
computer's power supply. Maybe - but irrelevant due to the adjacent
protector.

Protector did its job - MOVs shunted (connected, diverted) surge
current into all other AC wires including the green safety ground
wire. Green wire connects directly to motherboard and network cards -
still seeking earth ground.

Path to earth was through the network and into a third computer.
Through that third computer's motherboard, through modem, and to earth
via phone lines. Semiconductors in these paths were damaged.

Any competent source (including the IEEE guide) along with any competent
manufacturer will tell you all interconnected equipment needs to be
connected to the same plug-in suppressor, or interconnecting wires need
to go through the suppressor. External connections, like phone, also
need to go through the suppressor. Connecting all wiring through the
suppressor prevents damaging voltages between wires going to the
protected equipment.

This is apparently way to complicated for w_ to understand.

For a more detailed explanation, read (starting pdf page 39) the IEEE
guide titled "Ground potential rise"
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf

The same section explains how plug-in suppressors work.

Plug-in protector is not for and does not claim to protect from this
typically destructive type of surge.

Complete nonsense. Just another of w_'s bizarre ideas.

But the same
ineffective protection is demonstrated in Bud's citation - 8000 volts
destructively on Page 42 Figure 8. That surge was permitted inside
the building. Plug-in protector did nothing to avert 8000 volts
destructively via the adjacent TV.

The illustration in the IEEE guide has a surge coming in on a cable
service. There are 2 TVs, one is on a plug-in suppressor. The plug-in
suppressor protects TV1, connected to it.

The point of the illustration for the IEEE is "to protect TV2, a second
multiport protector located at TV2 is required." Apparently a radical
idea for w_.

w_ says suppressors must only be at the service panel. In this example a
service panel protector would provide absolutely *NO* protection. The
problem is the wire connecting the cable entry block to the power
service 'ground' is too long. The IEEE guide says in that case "the only
effective way of protecting the equipment is to use a multiport protector."

What would have avoided above network damage? Homeowner later
installed and earthed a 'whole house' protector.

A power service suppressor is a real good idea. It does not protect
equipment connected to both power and signal wires if there is a high
voltage between those wires as in the example above. There are other
hazards that it also misses.

For independent advice read the IEEE or NIST guides. (Both say plug-in
suppressors are effective).

 

[bud--]

On May 3, 6:40 am, (e-mail address removed) wrote:

Bud claims plug-in protectors provide a complete protection system -
can protect from all types of surges. A plug-in protector only
protects from surges that rarely damage appliances.

Complete nonsense.

If not using a 'whole house' protector, well, even 'scary pictures'
created by typically undersized protectors now creates a hazard.

The lie resurrected.
Still missing - a link to any source that says UL listed plug-in
suppressors made after 1998 are a problem.

And undersized is a red herring. UL requires at least a minimal size.
Suppressors with much higher ratings are readily and cheaply available.

Bud disputes this. Bud says if all wires connect to the same
protector, then surge energy somehow disappears.

Poor w__ is unable to understand the IEEE guide. Clearly explained
(starting pdf page 40) - plug-in suppressors work primarily by CLAMPING
the voltage on all wires (signal and power) to the common ground at the
suppressor. Plug-in suppressors do not work primarily by earthing (or
stopping or absorbing). The guide also explains earthing occurs
elsewhere, not through the plug-in suppressor.


Still never seen - a source that agrees with w_ that plug-in suppressors
are NOT effective.

Still never seen - answers to simple questions:
- Why do the only 2 examples of surge suppression in the IEEE guide use
plug-in suppressors?
- Why does the NIST guide says plug-in suppressors are "the easiest
solution"?
- Why do all but one of w's "responsible manufacturers" make plug-in
suppressors?
- Why does SquareD say in addition to their "whole house" suppressors
"electronic equipment may need additional protection" from plug-in
suppressors.
- Why aren't airplanes crashing daily when they get hit by lightning (or
do they drag an earthing chain)?

For real science read the IEEE and NIST guides. Both say plug-in
suppressors are effective.

 

[w_tom]

Prpbably wannabee ham came from CB crowd when Morse code
requirement was dropped.

Technology cannot be challenged? So you attack the messenger? Rush
Limbaugh would be proud. Same mockery also proved Saddam had WMDs.
At what point do you learn from professional citations - ask questions
about the science?

Ham radio operators who actually know enough about electricity to
understand surge protection also define protection in terms of
earthing. How many QST articles did you ignore – therefore not
understand what Phil, et al post? Another ham who learned: Bill
Otten in rec.radio.shortwave on 5 Aug 2005 entitled "grounding and
surge":
http://tinyurl.com/79xoa
and
http://home1.gte.net/res0958z/

Another station engineer who also says surge damage is avoidable -
but then, unlike Tony Hwang, he did his job; learned from his
experience:
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, ...
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.

You claim to be a responsible station engineer. But you had a
lightning strike that created building damage and communication
equipment damage. No decent broadcasting engineer would have
considered that acceptable. Only one who did not even learn from QST
magazine would post foolishly blame Ufer grounds for making damage.

Yes an Ufer ground can result in damage when installed by a layman
who failed to learn the science. Rather than learn, Tony Hwang
declares failure as acceptable. Why are Ufer ground used? Because
Ufer grounding provided protection from direct strikes even to
munitions storage lockers - without damage. How curious. Ufer ground
work great where Tony Hwang is not in charge. Since Tony's facility
was not properly constructed or properly maintained, then Tony
considers damage acceptable. Failure is acceptable.

Educated station managers know lightning damage need not ever cause
damage. When damage does happen, then responsible station managers
find and eliminate the mistake. Tony Hwang knows otherwise; damage is
acceptable - that nothing can protect from lightning. So Tony Hwang
posts mockery and insults - and no technical facts.

How curious. Tony's peers learn from the damage, then eliminated
it.

 

[bud--]

Bud is focusing on the low frequency energy and
seems to think that is all there us because a lot of documents focus
on it because more energy is in the low frequencies. Also, surges
that come from a greater distance have the higher frequencies reduced.

Bud either does not understand the high frequency energy or just does
not believe it can happen. All lightning strikes have it.

Bud has provided 2 sources that directly contradict Phil. (Of course
they are not as smart as Phil.)

Phil has provided no sources to support Phil's Phantasy Physics.

(But this is *Phil* - why should he need sources?)