Clothes Dryer Moisture Sensor

w_tom wrote:
.


. Already posted and ignored. And I already told you 3 times that I already told you.
But w_ doesnt answer questions: - Was the UL standard revised as w_'s own hanford link said? - Did that revision require thermal protection next to the MOVs as w_'s own hanford link said? - What was the date of that revision - which w_'s own hanford link said was UL1449 2ed? - Where specifically in any of w_'s links did anyone say a damaged suppressor had a UL label? - Why do the only 2 examples of protection in the IEEE guide use plug-in suppressors? - How would a service panel suppressor provide any protection in the IEEE example, pdf page 42? .

. Intelligence is not w_. . >Bud cannot deny what

. On the contrary, I agree with Martzloff: "Mitigation of the threat can take many forms. One solution. illustrated in this paper, is the insertion of a properly designed [multiport plug-in surge suppressor]." And: "Whole house protection consists of a protective device at the service entrance complemented by [plug-in surge suppressors] for sensitive [electronic equipment] within the house." And: "Plug-in suppressors are "the easiest solution". Why did he write those things w_??? Why don't you answer questions??
Bizarre claim - plug-in surge suppressors don't work. Never any sources that say plug-in suppressors are NOT effective. Twists opposing sources to say the opposite of what they really say. Invents opinions and attributes them to opponents. Attempts to discredit opponents. w_ is a purveyor of junk science.
For real science read the IEEE and NIST guides. Both say plug-in suppressors are effective.
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| On the contrary, I agree with Martzloff: | "Mitigation of the threat can take many forms. One solution. illustrated | in this paper, is the insertion of a properly designed [multiport | plug-in surge suppressor]." | And: | "Whole house protection consists of a protective device at the service | entrance complemented by [plug-in surge suppressors] for sensitive | [electronic equipment] within the house." | And: | "Plug-in suppressors are "the easiest solution".
"Easy" does not necessarily mean "best".
| Bizarre claim - plug-in surge suppressors don't work.
That's not bizarre at all. Made as a general statement, that claim is not true. However, there are CIRCUMSTANCES where a "point of use protectivce device doubling as a multi-tap power distribution device" can make things worse. Most of those circumstances would not have this issue if all the wiring of the house is done correctly and protected by whole house entry protection. The really bizarre claim: that these devices will always provide protection in all cases. My bet is that Martzloff is careful to show them being used in cases where they do provide protection.
| Never any sources that say plug-in suppressors are NOT effective.
If a source describes 1 or 2 or 3 circumstances where they ARE effective, do you take that to mean they are effective in all possible circumstances? I would not do so. My bet is that Martzloff is careful to show them being used in cases where they do provide protection.
| Twists opposing sources to say the opposite of what they really say. | Invents opinions and attributes them to opponents. | Attempts to discredit opponents. | w_ is a purveyor of junk science.
He has his errors. But in some postings he has made, he didn't post any.
| For real science read the IEEE and NIST guides. Both say plug-in | suppressors are effective.
Those papers are not science at all. They are merely a guide to what the authors believe are examples of solutions. They do not cover every possible scenario (which may be part of the agenda).
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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| Ho-hum. The village idiot again omits what Martzloff really wrote about | plug-in suppressors in that technical paper: | "Mitigation of the threat can take many forms. One solution. illustrated | in this paper, is the insertion of a properly designed [multiport | plug-in surge suppressor]."
And just what does Martzloff think happens to the surge energy? Does he think it is just destroyed and ceases to exist?
| And poor w_ still hasn?t explained why Martzloff wrote:
Really, I think it should be your responsibility to explain Martzloff since you're the one always promoting him.
| "Whole house protection consists of a protective device at the service | entrance complemented by [plug-in surge suppressors] for sensitive | [electronic equipment] within the house." | And: | "Plug-in suppressors are "the easiest solution".
Easiest does not imply right.
But if the whole house protection is present, mosts of the problems a point of use protector could have won't come to it in the first place.
| And still no link to another lunatic that says plug-in suppressors are | NOT effective. w_ can?t even find one source that agrees that plug-in | suppressors are NOT effective????
What good are links?
I have no interest in links to any comments by anyone that cannot explain WHY they think things are the way they are.
And how often does Martzloff provide links to other lunatics?
Point of use protectors can, by themselves without any whole house surge protection, in some cases, have a benefit. But in some other cases they can make things worse. However, when the whole house surge protection is present, the set of cases where point of use protection causes problems becomes a much smaller set.
| - Why do the only 2 examples of protection in the IEEE guide use plug-in | suppressors?
Did they ALSO have whole house protection at the same time?
| - How would a service panel suppressor provide any protection in the | IEEE example, pdf page 42?
The IEEE didn't explain that in their document?
| Why no answers w_???
Maybe because he didn't write the document. IEEE did. Ask them.
| Bizarre claim - plug-in surge suppressors don't work.
There are cases where all three scenarios can be: 1. They work and provide protection. 2. They have no effect. 3. They make things worse.
| For real science read the IEEE and NIST guides. Both say plug-in | suppressors are effective.
But they do NOT explain why. And bud seems to always think w_tom could explain why IEEE and NIST wrote these things.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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| snipped-for-privacy@ipal.net wrote:
|> | . |> |> | Martzloff specifically looked at whether branch circuits exhibited |> |> | transmission line characteristics. They don't, as I previously posted |> |> | (ignored of course). But we all know Martzloff had a hidden agenda. |> |> |> |> If you believe Martzloff (re: branch circuits do not have transmission |> |> line characteristics) then I challenge you and him both to explain how, |> |> in terms of PHYSICS, that this can be so. I have used NM 14/2 cable as |> |> a TV feedline before. It works. It works as well as twin line. It is |> |> stupid to waste such expensive cable when mere twin line is sufficient. |> |> It was a temporary measure at the time because I was out of twin line. |> | . |> | It should have been obvious from the context that Martazloff was |> | investigating if branch circuits exhibit transmission line |> | characteristics *for surges*. They don't. (But Martzloff had a hidden |> | agenda.) |> |> Then he flubbed the experiment. Is *HE* willing to disclose how he did |> the experiment? I can't be specific in challenging his errors if I do |> not know what it is he did. I can only challenge him in general. | . | One source (not the only one) is: | http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Propagation%201983.pdf | This is a technical paper published by the IEEE.
He dismisses "short pulses" without an explanation of why. Maybe it could be that agenda thing?
He doesn't even address fast rise edge transitions.
| On transmission line behavior Martzloff writes: | "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."
He is already assuming a slow rise impulse. This isn't applicable to the points I raised.
| Houses don't have 200 meter branch circuits. In addition, the 1.2us rise | time Martzloff used is not likely. The source impedance of wiring from | the point-of-strike to a house attenuates the highest frequency | components and gives a slower rise. The typical test surge, IIRC, is | 8/20. That would require a much longer branch circuit.
"Houses don't have 200 meter branch circuits" ... certainly no _normal_ house would have anything close to that. OTOH, if they did, they would not have so much of an issue with surges as that long wiring would work in favor of attenuating the short rise pulses and edges that Martzloff so conveniently dismisses.
| ---------------------------- | Martzloff also writes: | "Will the impinging surge be in the normal mode (black to white) or in | the common mode ([black-and-white-to-green)?" | This is not your definition of a common mode surge (but it is my | definition).
Definitions of modes is, in part, a word game. There are many modes that can actually happen. They can all be described in terms of a combination of differential and common mode. The term "normal" might be a custom in this field of engineering, but it is a term within inherint meaning.
| Martzloff shows using 1-3 MOVs at the end of a branch circuit for surge | suppression. He indicates none of the problems you say exist.
Because in the remainder of this paper he isn't addressing them. He is addressing the slow rise impulses up to make a few hundred kHz equivalent frequency.
| None of the 6 experienced EEs who wrote the guides agrees with you. (But | they all probably had a hidden agenda.)
Either the hidden agenda, or maybe just a lack of interest in their part to explore the field of fast rise time pulses and edge transitions.
| Where are your sources???
Where are YOURS? You "came to a gun fight with a knife". Your evidence doesn't even deal with fast rise time issues.
|> My sources for physics are college classes I have taken, as well as other |> readings in the past. Physics is one of my areas of understanding. | . | Apparently no degree in EE but you can accuse a respected electrical | engineer, who has many published papers on surges and protection, of | having a hidden agenda.
You seem to be a good source of his papers. Maybe you've read many others. If so, maybe you would do better than I at finding what he has written on fast rise time issues (as opposed to the paper you offered that did not).
Or maybe he hasn't written any. Maybe his "hidden agenda" is merely his interest in researching low rise time impulses (after all, they do happen more often then fast rise time impulses, which generally require a direct strike on the service drop).
FYI, I'm talking about rise times on the order of 1000 volts per NANOsecond or faster.
|> not know all areas of physics, but I do know transmission lines. | . | "If all you have is a hammer everything looks like a nail?"
Pounding a screw into wood might not be very efficient, but it can get the screw into the wood.
A fast rise impulse/edge might not propogate on NM as well as it would on TV twin-lead, but it can still have significant damaging energy at the far end. Remember, normal houses don't have 200 meter branch circuits.
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snipped-for-privacy@ipal.net wrote:

. Because the points you raised are not relevant to real world surges. .

. A word game for you - the "physics of phil". Not for engineers. This is an engineering newsgroup. .

. Martzloff, and others, are interested in science that applies to the real world. .

. So the hidden agenda of the 6 EE authors is that they are interested in real world surges. Martzloff has a paper on a direct strike to the primary on a power pole behind a house. The estimated average probability of a surge more severe is 1 in 8000 years. You are interested in events that take place at a house less than once in 8000 years. Real useful.
But Martzloff also has a paper on a lightning strike to the neutral at the service drop-to-riser connection. No mention of transmission line effects. Must be another hidden agenda (his third one?) .

. Martzloff deals in real world surges. Real world investigations have determined what real world surges look like. Martzloff has used surges from IEEE standards in his investigations.
Really sounds like your post is a CYA attempt. In any case, you have still given no sources. Including no sources for nanosecond rise times. I have furnished at least 3. You dismiss them because they do not apply to lala land where you reside. I am only interested in physics for the real world.
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| snipped-for-privacy@ipal.net wrote:
|> |> | . |> |> |> | Martzloff specifically looked at whether branch circuits exhibited |> |> |> | transmission line characteristics. They don't, as I previously posted |> |> |> | (ignored of course). But we all know Martzloff had a hidden agenda. |> |> |> |> |> |> If you believe Martzloff (re: branch circuits do not have transmission |> |> |> line characteristics) then I challenge you and him both to explain how, |> |> |> in terms of PHYSICS, that this can be so. I have used NM 14/2 cable as |> |> |> a TV feedline before. It works. It works as well as twin line. It is |> |> |> stupid to waste such expensive cable when mere twin line is sufficient. |> |> |> It was a temporary measure at the time because I was out of twin line. |> |> | . |> |> | It should have been obvious from the context that Martazloff was |> |> | investigating if branch circuits exhibit transmission line |> |> | characteristics *for surges*. They don't. (But Martzloff had a hidden |> |> | agenda.) |> |> |> |> Then he flubbed the experiment. Is *HE* willing to disclose how he did |> |> the experiment? I can't be specific in challenging his errors if I do |> |> not know what it is he did. I can only challenge him in general. |> | . |> | One source (not the only one) is: |> | http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Propagation%201983.pdf |> | This is a technical paper published by the IEEE. |> | On transmission line behavior Martzloff writes: |> | "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." |> |> He is already assuming a slow rise impulse. This isn't applicable to the |> points I raised. | . | Because the points you raised are not relevant to real world surges.
And you didn't have a Martzloff quote/source for this absurd statement?
|> | ---------------------------- |> | Martzloff also writes: |> | "Will the impinging surge be in the normal mode (black to white) or in |> | the common mode ([black-and-white-to-green)?" |> | This is not your definition of a common mode surge (but it is my |> | definition). |> |> Definitions of modes is, in part, a word game. | . | A word game for you - the "physics of phil". Not for engineers. This is | an engineering newsgroup.
Maybe your special brand of engineering ignores sciences like physics.
|> |> My sources for physics are college classes I have taken, as well as other |> |> readings in the past. Physics is one of my areas of understanding. |> | . |> | Apparently no degree in EE but you can accuse a respected electrical |> | engineer, who has many published papers on surges and protection, of |> | having a hidden agenda. |> |> You seem to be a good source of his papers. Maybe you've read many others. |> If so, maybe you would do better than I at finding what he has written on |> fast rise time issues (as opposed to the paper you offered that did not). | . | Martzloff, and others, are interested in science that applies to the | real world.
And you've never seen a surge event involving a high rise transient? I have ... twice. And they make up 1/3 of surge events I have witnessed.
|> Maybe his "hidden agenda" is merely his |> interest in researching low rise time impulses (after all, they do happen |> more often then fast rise time impulses, which generally require a direct |> strike on the service drop). | . | So the hidden agenda of the 6 EE authors is that they are interested in | real world surges. Martzloff has a paper on a direct strike to the | primary on a power pole behind a house. The estimated average | probability of a surge more severe is 1 in 8000 years. You are | interested in events that take place at a house less than once in 8000 | years. Real useful. | | But Martzloff also has a paper on a lightning strike to the neutral at | the service drop-to-riser connection. No mention of transmission line | effects. Must be another hidden agenda (his third one?)
Why don't you write to him and ask him why it is he omits transmission line effects? While writing, ask him how much line inductance is needed to bring a direct strike into the the slow rise time ranges he studies.
|> FYI, I'm talking about rise times on the order of 1000 volts per NANOsecond |> or faster. | . | Martzloff deals in real world surges. Real world investigations have | determined what real world surges look like. Martzloff has used surges | from IEEE standards in his investigations.
They've missed a lot of reality.
| Really sounds like your post is a CYA attempt. In any case, you have | still given no sources. Including no sources for nanosecond rise times. | I have furnished at least 3. You dismiss them because they do not | apply to lala land where you reside. I am only interested in physics for | the real world.
I'm not currently studying this, so I have no sources right here. I did that kind of study around 25 years ago. I've confirmed it with some real world experiences seeing events that consist of either only high rise time or events that are apparently a combination (yes, you can have both at the same time, too).
To provide sources now, I'd have to spend the time to dig it up. But you are not worth that effort. I'm only arguing it now because it is brought up now. So if you want, you can skip offering any sources about real life lightning transient curves, and it can just be the two of us arguing, as this doesn't take much of my time.
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snipped-for-privacy@ipal.net wrote:

. So to sum up:
Misuse of "common mode surge" - it is just a "word game".
Lack of any coverage of 'fast transients' by 6 EEs experienced in surges and surge suppression, and in the IEEE standards that define surge testing - "They've missed a lot of reality."
Expert engineer in field says branch circuits dont exhibit transmission line effects - the expert doesnt understand (perhaps another hidden agenda).
Total lack of sources - I studied it 25 years ago.
Apparently the only expert is phil (in phil's mind).
You are educated beyond your intelligence. Maybe at one of those schools where multiple realities are equally valid.
You have a bright, but alas short, future as a science advisor in the Bush administration. You can join w_ there.
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| So to sum up: | | Misuse of "common mode surge" - it is just a "word game".
It is not clear what your meaning is. Are you claiming that there is no such thing as a "common mode surge"?
| Lack of any coverage of 'fast transients' by 6 EEs experienced in surges | and surge suppression, and in the IEEE standards that define surge | testing - "They've missed a lot of reality." | | Expert engineer in field says branch circuits don?t exhibit transmission | line effects - the expert doesn?t understand (perhaps another hidden | agenda).
All conductors have transmission line effects. But at low frequencies where the transmission line length is a small fraction of the wavelength, these transmission line effects are insignificant. The distinction is the frequency.
| Total lack of sources - I studied it 25 years ago.
Did you study what makes a transmission line a transmission line?
| Apparently the only expert is phil (in phil's mind).
6 EE's that ignore the fast rise time transients that can be clearly recorded in UHF spectra are certainly no experts of the _whole_ field of surges. But maybe they have defined "surge" to be a subset of all the electrical risks that exist from lightning. That might be a lot easier than having to go bone up on transmission lines.
| You are educated beyond your intelligence. Maybe at one of those schools | where multiple realities are equally valid.
Which school would that be?
| You have a bright, but alas short, future as a science advisor in the | Bush administration. You can join w_ there.
It seems all science advisors have short futures in the Bush administration. Bush is like Bud. Both ignore science in favor of their political agenda.
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On Sun, 09 Mar 2008 20:16:38 GMT snipped-for-privacy@abc.net wrote:
| You are all spending time talking surge suppression systems and are ignoring
Actually, no they are not. They are just having a game of bashing each other over the head and calling it a surge.
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Bud's own posts, including Page 42 Figure 8, say otherwise. Protectors without earth ground are not an effective solution to surges that seek earth ground.
When utilities do not enter at a common point, then a better solution is to make a lager single point ground by merging all electrodes with a buried wire. The title is "Preventing Damage Due to Ground Potential Difference". A utility demonstrates how to accomplish this in wrong, right, and preferred pictures: http://www.cinergy.com/surge/ttip08.htm
Protection is only as effective as the earth ground. Bud says otherwise to promote plug-in protectors that have no effective earthing. That 'buried bare copper wire' solution recommended to "Prevent Damage ..." makes every earthing connection both more conductive AND interconnects all to a single point ground.
Two reasons are why earthing provides protection. For even better protection, some loop a building with a buried ground wire - techniques such as halo or Ufer grounds. Effective protection is about conductivity and equipotential. That buried ground wire improves both making all appliances even better protected. Protection is only as effective as the earthing which is why high reliability facilities are obsessive about their earthing.
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w_tom wrote:

. 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, and anyone who can think, is "to protect TV2, a second multiport protector located at TV2 is required." What a radical idea.
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 (not a "single point ground"). The IEEE guide says in that case "the only effective way of protecting the equipment is to use a multiport protector." This is the same as what is quoted from me at the top. .

. w_ has a religious belief (immune from challenge) that surge protection must use earthing. Thus in his view plug-in suppressors (which are not well earthed) can not possibly work. The IEEE guide explains plug-in suppressors work 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 explains earthing occurs elsewhere. (Read the guide starting pdf page 40). .

. I promote only accurate information. w_ promotes religious dogma. .

. From http://www.lightningsafety.com/nlsi_lhm/grounding_definitions.html Halo Grounded Ring: A grounded No. 2 wire, installed around all four walls inside a small building, at an elevation of approx. six inches below the ceiling. They are used around transmitter equipment. How would a halo ground help? Perhaps w_ could learn the proper term.
Both the IEEE and NIST (below) guides say equipotential of the ground references for power, telephone, cable requires a *short* connection from the phone and cable entrance protectors to the earthing wire at the power service.
Everyone agrees earthing is a good idea. The question is whether plug-in suppressors work. The IEEE guide says plug-in suppressors are effective.
So does an NST guide (written by Martzzloff but aimed at the unwashed masses) at: http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf Read the sources.
There are 98,615,938 other web sites, including 13,843,032 by lunatics, and w_ can't find another lunatic that says plug-in suppressors are NOT effective.
Simple questions never answered: - Why do the only 2 examples of protection in the IEEE guide use plug-in suppressors? - Why does the NIST guide says plug-in suppressors are "the easiest solution"? - How would a service panel suppressor provide any protection in the IEEE example, pdf page 42?
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| w_ has a religious belief (immune from challenge) that surge protection | must use earthing. Thus in his view plug-in suppressors (which are not | well earthed) can not possibly work. The IEEE guide explains plug-in | suppressors work 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 explains | earthing occurs elsewhere. (Read the guide starting pdf page 40).
If the cable wire comes in through that plug in suppressor, then it can have some effect at reducing the surge. Just how much will depend on the impedance of the ground it is attached to. The circuit ground wire is a path to ground (assume the system is installed right). But it is not that great of one for a high rise surge. If it had direct earthing it could do better, depending on the characteristic impedance of that path.
| Everyone agrees earthing is a good idea. The question is whether plug-in | suppressors work. The IEEE guide says plug-in suppressors are effective.
They do provide better protection than not having one, whether one has any of the other protections or not. But one must not be fooled into the false sense of protection by having one alone. Bringing all wires in at a common entrance and protecting them all with solid low impedance paths to ground is a very important level of protection to also have. None of the protections are 100%.
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snipped-for-privacy@ipal.net wrote:

. You obviously have not read the IEEE guide starting pdf page 40. My explanation - clamping to the common ground at the suppressor - is exactly what is described. The TV sees wires that have safe voltages with respect to each other. Plug-in suppressors do NOT work primarily by earthing.
But maybe the IEEE has a hidden agenda.
You ignore what I write. You ignore sources. In ham circles you are a monologuist.
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| snipped-for-privacy@ipal.net wrote:
|> |> | w_ has a religious belief (immune from challenge) that surge protection |> | must use earthing. Thus in his view plug-in suppressors (which are not |> | well earthed) can not possibly work. The IEEE guide explains plug-in |> | suppressors work 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 explains |> | earthing occurs elsewhere. (Read the guide starting pdf page 40). |> |> If the cable wire comes in through that plug in suppressor, then it can |> have some effect at reducing the surge. Just how much will depend on |> the impedance of the ground it is attached to. The circuit ground wire |> is a path to ground (assume the system is installed right). But it is |> not that great of one for a high rise surge. If it had direct earthing |> it could do better, depending on the characteristic impedance of that |> path. | . | You obviously have not read the IEEE guide starting pdf page 40. My | explanation - clamping to the common ground at the suppressor - is | exactly what is described. The TV sees wires that have safe voltages | with respect to each other. Plug-in suppressors do NOT work primarily | by earthing.
This depends on the energy mode, common mode vs. differential (traversal) mode. You can have either or both situations. You can choose to have a surge suppressor ungrounded, grounded via the ground wire, or earthed directly on its own.
| But maybe the IEEE has a hidden agenda.
Or maybe you just don't grok the full range of possible surges and how high rise time energy propogates.
| You ignore what I write. You ignore sources. In ham circles you are a | monologuist.
The monologuist ignores everyone. You are not everyone. Your logic fails.
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Bud distorts to protect profits. Bud says protection is 'clamping to nothing'. Every responsible source including NIST, IEEE, and the many organizations that 'need protection that works' all say clamping must be to earth ground. Conservation of energy. Where is energy dissipated? According to Bud, that energy is dissipated inside the protector by "clamping to nothing" or magically disappears. According to responsible professionals: energy must be dissipated in earth. No earth ground means no effective protection.
Both articles from Electrical Engineering Times are titled "Protecting Electrical Devices from Lightning Transients". Engineers define protection. Will they discuss Bud's protectors? Of course not. The article is about protection; not about myths. EE Times discusses real world protection in two front page articles on 1 Oct and 8 Oct 2007: http://www.planetanalog.com/showArticle.jhtml?articleID 1807127 http://www.planetanalog.com/showArticle.jhtml?articleID 1807830
What provides protection? Earth ground. Wire impedance is why 'clamping' to earth must be short, no splices, no sharp bends, etc. "Clamping to nothing"? Of course not. The article is about real world protection: clamping (also called shunting, connecting, diverting) to earth ground. "Clamping to nothing' is the scam.
Bud will reply again. Bud must post until he has the last reply. Then you will believe him rather than every responsible industry professional.
As I do repeatedly, just another professional defines effective protection: Kenneth Schneider PhD Telebyte USA: http://www.arcelect.com/lightnin.htm

Bud says protection is "clamping to nothing". Somehow surge energy will magically disappear? Yes, according to every Bud post. Every source cited by Bud has contradicted what Bud claims. Even Bud's Page 40 citation contradicts him: on Page 42 Figure 8. No earth ground means no effective protection.
An effective protector earths a direct lightning strike - without damage. The effective protector must remain functional after every surge. Is that surge protector damaged by a surge? Then it may be the grossly undersized and obscenely profitable protector promoted by Bud.
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On Wed, 27 Feb 2008 08:02:42 +0000 (GMT) charles
|> | |> |>I'd run my computers on 240 volts L-L if I could find a correct surge |> |>protector for that. |> | |> | I don't know why you would want to except to just be different but you |> | can order a surge strip from UK or some other "across the ponmd" |> | country and get a few line cords for your PC hardware that match the |> | strip. You will have to install a 6-15 plug on it tho. |> | The PC end will be the same (IEC320) | |> I have a German one ... Schuko plug, 5 Schuko outlets. But these are |> designed for 230 volts (close enough to 240) between current carrying |> conductors as well as 230 volts between either of them and ground. |> That doesn't match the US system, which needs 120 volt protection |> between current carrying conductors and ground. | | If the protection works at 240v it will also work at 120v or anything lower.
But it won't work correctly. It won't provide the full protection.
|> So it needs to be of a different design for the different ground |> relationship. | | Sorry, what different "ground relationship"? It's still less than 240v.
The clamping voltage is at a certain percentage above the waveform peak voltage. Less than that risks false clamping. More than that and you don't get the protection of smaller surges.
I don't recall exactly what that best ratio actually is. Clearly it has to be above the waveform peak. So for 120 volts it needs to be above 170 volts. For 240 volts it needs to be above 340 volts. For the sake of discussion for now, I'll assume the ideal value would be 200 volts for a 120-volt L-N system (US) and 400 volts for a 240-volt L-N system (UK).
A surge protector for a L-N system would have the MOV devices wired not only L-N, but also L-G and even N-G (offering protection against surges relative to ground on the neutral wire, but not going mad if the wiring is reversed). All these would be 200 volt devices for a surge protector in the US, and 400 volt devices for a surge protector in the UK.
Using the UK surge protector in the US would be "safe" in the sense of no false clamps. The reverse is not true.
A surge protector for a L-L system, as 240 volts is in the US, needs to be wired differently. The 200 volt MOV devices would be used between each line wire and ground. But 400 volt MOV devices would be used between the two line wires.
Using a UK surge protector on the US 240 volt system would provide less protection of any L-G surge. A surge of 360 volts L-G would not be clamped to ground.
I suppose what I could do is take my Schuko surge protector and replace all the L-G wired devices with lower voltage ones taken from a common NEMA 5-15 surge protector. But I would rather just have an engineer with specific experience in this be sure it is designed correctly, and manufactured correctly, and even tested at the UL or other labs. Would they know what to do with a surge protector that comes in for testing with a NEMA 6-15P plug and a few NEMA 6-15 outlets? I bet they would.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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