Clothes Dryer Moisture Sensor

snipped-for-privacy@ipal.net wrote:


. You are disagreeing with Martzloff, who has done a lot of research on surge protection an has numerous published papers. The same immunity has also appeared elsewhere such as a PCMagazine review of plug-in suppressors. .

. Contrary - overvoltage is the major cause of failure? - you are again disagreeing with Martzloff.
Contrary - not intended to protect against swells and overvoltage? - provide a source that says plug-in suppressors are intended to protect against swells and overvoltage. Like maybe specs from few manufacturers that Ed asked for.
"Put forth your theory ahead of time" - apparently a new newsgroup requirement? .

. By the time current reached well over 15A required to trip a 15A breaker in a short time, the MOV would be toast. UL has required since 1998 that thermal disconnects be provided to disconnect overheating MOVs. Or fuses as Greg suggests, but selected by the manufacturer which can have operating characteristics closely matched to the MOVs, may also open. It is unlikely that protection would come from a breaker.
Repeating: "The IEEE guide goes on a length how the protected load can be connected across the MOVs or connected to the incoming line. If connected across the MOVs, the protected load will be disconnected when overheating MOVs are disconnected on failure." Similar comments are in the NIST guide.
Your response was "And you are saying what?"
What: that is the probable protection route indicated in both guides if a plug-in suppressor can provide protection from overvoltage. Both guides make clear not all plug-in suppressors are wired to disconnect the protected load with the MOVs. .

. Repeating: "To protect against overvoltage get a suppressor that disconnects on overvoltage." They disconnect the load and MOVs. .

. "He"? Is "he" Martzloff? I have never seen Martzloff indicate a MOV based surge suppressor should protect against swells or overvoltage.
The "IEEE Recommended Practice for Powering and Grounding Sensitive Electronic Equipment" (Emerald book) does not indicate plug-in suppressors are an effective means of protecting against swells or overvoltage.
Perhaps you could use a plug-in suppressor with overvoltage protection built in, as above.
If you want to use failure of MOVs to protect your equipment I would suggest a suppressor from a reputable manufacturer where the manufacturer says the suppressor will protect from swells and overvoltage. Given hype, I suggest using a device where the manufacturer also has a warrantee on protected equipment.
Saying plug-in suppressors should protect against swells and overvoltage they are not designed for does not make them effective.
=======================Or perhaps you could use a device the Emerald book indicates might be effective. For houses that would be a UPS. But make sure the manufacturer says the UPS will protect against swells and overvoltage.
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| snipped-for-privacy@ipal.net wrote:
|> |> On Fri, 29 Feb 2008 02:23:56 -0500 Michael A. Terrell
|> |> |>
|> |> |> |> |> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> |> |> | suppressor] failures is a temporary overvoltage, rather than an |> |> |> | unusually large surge." |> |> |> |> |> |> And these would not damage the TV? |> |> | |> |> | |> |> | No. Why do you think it would? if the surge suppresser clips at a |> |> | safe voltage to protect from spikes, it won't go any higher with a |> |> | overvoltage condition, but the MOV or other protection device quickly |> |> | overheats as it tries to maintain the proper voltage. If the line |> |> | voltage is high enough, it will trip the Breaker, or blow the fuse for |> |> | that AC circuit. The protective device can only dissipate a small |> |> | amount of heat before it self destructs. |> |> |> |> This was a discussion about a suggestion tha the MOV condunction voltage |> |> should be higher than now used (330V for 120V systems). He wants to |> |> raise that voltage to avoid certain situations causing TVSS failure so |> |> the protection against spikes (above 800V) is maintained longer. My |> |> position is that the swells as high as 565V RMS could in fact cause |> |> damage to the TV. Under his proposal, these would be be suppressed. |> |> I think that is a bad idea because these voltage swells really can do |> |> damage. |> | . |> | Surge suppressors are intended to protect against surges. Raising the |> | clamp voltage is to lower unnecessary suppressor exposure to surges that |> | do not damage connected equipment. |> |> The last 7 words are the part we do not agree on. | . | You are disagreeing with Martzloff, who has done a lot of research on | surge protection an has numerous published papers. The same immunity has | also appeared elsewhere such as a PCMagazine review of plug-in suppressors.
Yes, I am disagreeing with him. I believe he has an agenda of some kind. What we have now works. I don't believe he has shown justification to make a change.
|> | Surge suppressors are not intended to protect against longer duration |> | swells or even longer duration overvoltage. Martzloff's comment above is |> | that the major cause of failure is overvoltage, which suppressors are |> | not intended to protect against. |> |> I've read discussions and online pages to the contrary. If you have put |> forth your theory ahead of time, I could have recorded the locations for |> you. | . | Contrary - overvoltage is the major cause of failure? - you are again | disagreeing with Martzloff. | | Contrary - not intended to protect against swells and overvoltage? - | provide a source that says plug-in suppressors are intended to protect | against swells and overvoltage. Like maybe specs from few manufacturers | that Ed asked for.
Yes, I still disagree with him. The "suppressors are not intended to protect against" is the point. BUT NOTE THIS VERY CAREFULLY ... I do not say he is wrong ... I say he has a twisted agenda in that regard. While they may not have been _intended_ to protect against overvoltage, they do have that capability and for many people, they have an expectation to do such protection. That's why I say leave things as they are.
| "Put forth your theory ahead of time" - apparently a new newsgroup | requirement?
It's not a requirement to post URLs of things read in the past if there was no expectation to need them. I save many URLs of many interesting things. But I can't save them all.
|> | If you keep the clamp voltage low, you are likely not increasing |> | protection from swells because a swell may well kill the MOV anyway. To |> | protect against overvoltage get a suppressor that disconnects on |> | overvoltage. |> |> The surge suppressor already does this. Sure, it can _die_ while doing |> this. The MOV shorts across, causing an increase in current that trips |> the supplementary breaker in the strip (usually integrated in the switch). |> There, appliance protected by one low cost device. | . | By the time current reached well over 15A required to trip a 15A breaker | in a short time, the MOV would be toast. UL has required since 1998 that | thermal disconnects be provided to disconnect overheating MOVs. Or fuses | as Greg suggests, but selected by the manufacturer which can have | operating characteristics closely matched to the MOVs, may also open. It | is unlikely that protection would come from a breaker.
So what if the MOV is toast. It's still the cost effective way to provide the protection. It's a rare event.
| Repeating: | "The IEEE guide goes on a length how the protected load can be connected | across the MOVs or connected to the incoming line. If connected across | the MOVs, the protected load will be disconnected when overheating MOVs | are disconnected on failure." Similar comments are in the NIST guide. | | Your response was "And you are saying what?"
Maybe if you had included an analysis, I would not have had to ask.
| What: that is the probable protection route indicated in both guides if | a plug-in suppressor can provide protection from overvoltage. Both | guides make clear not all plug-in suppressors are wired to disconnect | the protected load with the MOVs.
Those that don't have the disconnect need to have that added. That is a lot less expensive than adding a complex overvoltage protection system.
|> Maybe what should have proposed was that we use a more expensive device |> that integrates higher level MOVs with overvoltage sensors. | . | Repeating: | "To protect against overvoltage get a suppressor that disconnects on | overvoltage." They disconnect the load and MOVs.
Or get one that disconnects on MOV overcurrent that is the result of overvoltage. This latter idea will be lower in cost even when considering that each event requires replacing the protection device (because these events are rare). Martzloff does not appear to be considering the statistical economics. Maybe he has an agenda, like trying to sell more of some other kind of protection.
|> If he can |> show that such a MORE EXPENSIVE device is worth the extra cost in the |> longer term, he wins. But I think he cannot. | . | "He"? Is "he" Martzloff? I have never seen Martzloff indicate a MOV | based surge suppressor should protect against swells or overvoltage.
Maybe he doesn't want them to for some reason.
| The "IEEE Recommended Practice for Powering and Grounding Sensitive | Electronic Equipment" (Emerald book) does not indicate plug-in | suppressors are an effective means of protecting against swells or | overvoltage. | | Perhaps you could use a plug-in suppressor with overvoltage protection | built in, as above.
Can you point out a LOW COST ONE? My understanding is they have quite a high cost. But if you can point to one or two low cost ones, then I would be wrong.
| If you want to use failure of MOVs to protect your equipment I would | suggest a suppressor from a reputable manufacturer where the | manufacturer says the suppressor will protect from swells and | overvoltage. Given hype, I suggest using a device where the manufacturer | also has a warrantee on protected equipment. | | Saying plug-in suppressors should protect against swells and overvoltage | they are not designed for does not make them effective.
What something is designed for, and what it can do in certain cases, are not always the same thing. Then when manufacturers find out that their product already cheaply does what customers want that could have been done in a more expensive way to drive more revenue, they realise the golden goose has escaped the pen and are trying to round it back in.
| Or perhaps you could use a device the Emerald book indicates might be | effective. For houses that would be a UPS. But make sure the | manufacturer says the UPS will protect against swells and overvoltage.
This is exactly what I am describing. They want to sell something that is way more expensive, rather than admit that something cheap can do the same thing (though self-destructively).
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snipped-for-privacy@ipal.net wrote:

. So you assault the character of an electrical engineer that is an established authority on surges. And your assault occurs in an electrical engineering forum. Apparently Martzloff even fooled the IEEE which published his papers. And international conferences that also published his papers. Too bad they aren’t as smart as you. .

>

. Again impugning the integrity of an electrical engineer that is a recognized expert. .

. Gee. you forgot the specs from a few manufacturers. What a surprise. .

. "Put forth your theory ahead of time" is one of the stupidest comments I have seen in a newsgroup. .

. The point of this paragraph, which should be clear to anyone who can read, is that circuit breakers are not likely to trip. The point was not toast. .

. Maybe if you had any interest in what other people write you would have understood. . <....>

. Another outrageous slander. .

. You have not pointed to a plug-in suppressor that the manufacturer says is effective on swells and overvoltage. Maybe you are wrong. .

. Yea, those manufacturers are really stupid. Just like Martzloff. And the IEEE. And the NIST. .

. You dismiss UPSs, which the IEEE Emerald book says may be effective, for plug-in suppressors which the Emerlad book does not recommend.
You attack an electrical engineer that is a recognized expert.
You ignore what I post.
There isn’t much point in responding further.
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| snipped-for-privacy@ipal.net wrote:
|> |> |> On Fri, 29 Feb 2008 02:23:56 -0500 Michael A. Terrell
|> |> |> |>
wrote: |> |> |> |> |> |> |> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> |> |> |> | suppressor] failures is a temporary overvoltage, rather than an |> |> |> |> | unusually large surge." |> |> |> |> |> |> |> |> And these would not damage the TV? |> |> |> | |> |> |> | |> |> |> | No. Why do you think it would? if the surge suppresser clips at a |> |> |> | safe voltage to protect from spikes, it won't go any higher with a |> |> |> | overvoltage condition, but the MOV or other protection device quickly |> |> |> | overheats as it tries to maintain the proper voltage. If the line |> |> |> | voltage is high enough, it will trip the Breaker, or blow the fuse for |> |> |> | that AC circuit. The protective device can only dissipate a small |> |> |> | amount of heat before it self destructs. |> |> |> |> |> |> This was a discussion about a suggestion tha the MOV condunction voltage |> |> |> should be higher than now used (330V for 120V systems). He wants to |> |> |> raise that voltage to avoid certain situations causing TVSS failure so |> |> |> the protection against spikes (above 800V) is maintained longer. My |> |> |> position is that the swells as high as 565V RMS could in fact cause |> |> |> damage to the TV. Under his proposal, these would be be suppressed. |> |> |> I think that is a bad idea because these voltage swells really can do |> |> |> damage. |> |> | . |> |> | Surge suppressors are intended to protect against surges. Raising the |> |> | clamp voltage is to lower unnecessary suppressor exposure to surges that |> |> | do not damage connected equipment. |> |> |> |> The last 7 words are the part we do not agree on. |> | . |> | You are disagreeing with Martzloff, who has done a lot of research on |> | surge protection an has numerous published papers. The same immunity has |> | also appeared elsewhere such as a PCMagazine review of plug-in suppressors. |> |> Yes, I am disagreeing with him. I believe he has an agenda of some kind. |> What we have now works. I don't believe he has shown justification to |> make a change. | . | So you assault the character of an electrical engineer that is an | established authority on surges. And your assault occurs in an | electrical engineering forum. Apparently Martzloff even fooled the IEEE | which published his papers. And international conferences that also | published his papers. Too bad they aren?t as smart as you.
I am not being critical of specific statements he makes. From an engineering perspective, he is correct that by using a higher voltage MOV, surge suppressors would last longer. That is not in dispute.
What is in dispute is the worthiness of bothering to do this. He has not supported why this should be done. If MOV voltages go up, then the cost of full protection goes up because additional protection at the lower level is then needed.
|> Yes, I still disagree with him. The "suppressors are not intended to |> protect against" is the point. BUT NOTE THIS VERY CAREFULLY ... I do not |> say he is wrong ... I say he has a twisted agenda in that regard. | . | Again impugning the integrity of an electrical engineer that is a | recognized expert.
Being an expert in engineering has nothing to do with the applicable economics.
|> While |> they may not have been _intended_ to protect against overvoltage, they do |> have that capability and for many people, they have an expectation to do |> such protection. That's why I say leave things as they are. | . | Gee. you forgot the specs from a few manufacturers. What a surprise.
Show me _ANY_ manufacturer that publishes complete specs on what their products _CAN_ do (as opposed to what they merely market them to do).
|> |> | If you keep the clamp voltage low, you are likely not increasing |> |> | protection from swells because a swell may well kill the MOV anyway. To |> |> | protect against overvoltage get a suppressor that disconnects on |> |> | overvoltage. |> |> |> |> The surge suppressor already does this. Sure, it can _die_ while doing |> |> this. The MOV shorts across, causing an increase in current that trips |> |> the supplementary breaker in the strip (usually integrated in the switch). |> |> There, appliance protected by one low cost device. |> | . |> | By the time current reached well over 15A required to trip a 15A breaker |> | in a short time, the MOV would be toast. UL has required since 1998 that |> | thermal disconnects be provided to disconnect overheating MOVs. Or fuses |> | as Greg suggests, but selected by the manufacturer which can have |> | operating characteristics closely matched to the MOVs, may also open. It |> | is unlikely that protection would come from a breaker. |> |> So what if the MOV is toast. It's still the cost effective way to provide |> the protection. It's a rare event. | . | The point of this paragraph, which should be clear to anyone who can | read, is that circuit breakers are not likely to trip. The point was not | toast.
So you think that if an MOV begins a runaway conduction because the peak of an overvoltage causes it to fail, that this won't trip a breaker within a couple cycles?
Maybe the MOV will just clamp for the duration of the cycle peak, and not go into runaway conduction. Then don't worry. See above for the other case.
|> | Repeating: |> | "The IEEE guide goes on a length how the protected load can be connected |> | across the MOVs or connected to the incoming line. If connected across |> | the MOVs, the protected load will be disconnected when overheating MOVs |> | are disconnected on failure." Similar comments are in the NIST guide. |> | |> | Your response was "And you are saying what?" |> |> Maybe if you had included an analysis, I would not have had to ask. | . | Maybe if you had any interest in what other people write you would have | understood.
Well I sure have no interest (anymore) in what you write.
|> Martzloff does not appear to be considering the |> statistical economics. Maybe he has an agenda, like trying to sell more |> of some other kind of protection. | . | Another outrageous slander.
I accuse an engineer of not being an economist ... is a slander? That's very creative.
|> | The "IEEE Recommended Practice for Powering and Grounding Sensitive |> | Electronic Equipment" (Emerald book) does not indicate plug-in |> | suppressors are an effective means of protecting against swells or |> | overvoltage. |> | |> | Perhaps you could use a plug-in suppressor with overvoltage protection |> | built in, as above. |> |> Can you point out a LOW COST ONE? My understanding is they have quite |> a high cost. But if you can point to one or two low cost ones, then I |> would be wrong. | . | You have not pointed to a plug-in suppressor that the manufacturer says | is effective on swells and overvoltage. Maybe you are wrong.
Or maybe the manufacturer is hiding this so they can sell other stuff to unwitting people.
|> | If you want to use failure of MOVs to protect your equipment I would |> | suggest a suppressor from a reputable manufacturer where the |> | manufacturer says the suppressor will protect from swells and |> | overvoltage. Given hype, I suggest using a device where the manufacturer |> | also has a warrantee on protected equipment. |> | |> | Saying plug-in suppressors should protect against swells and overvoltage |> | they are not designed for does not make them effective. |> |> What something is designed for, and what it can do in certain cases, are |> not always the same thing. Then when manufacturers find out that their |> product already cheaply does what customers want that could have been done |> in a more expensive way to drive more revenue, they realise the golden |> goose has escaped the pen and are trying to round it back in. | . | Yea, those manufacturers are really stupid. Just like Martzloff. And the | IEEE. And the NIST.
I have not accused any of them of being stupid. I have accused them of possibly having an alternative agenda.
|> | Or perhaps you could use a device the Emerald book indicates might be |> | effective. For houses that would be a UPS. But make sure the |> | manufacturer says the UPS will protect against swells and overvoltage. |> |> This is exactly what I am describing. They want to sell something that |> is way more expensive, rather than admit that something cheap can do the |> same thing (though self-destructively). | . | You dismiss UPSs, which the IEEE Emerald book says may be effective, for | plug-in suppressors which the Emerlad book does not recommend.
This is the expensive "solution".
| You attack an electrical engineer that is a recognized expert.
... for his economic claims.
| You ignore what I post.
... because it is trash ... because you apparently don't even understand what it is I have said, since your responses don't even address what I was saying.
| There isn?t much point in responding further.
... I guess not.
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snipped-for-privacy@isp.com says...
<snip>

Actually, there is. Phil isn't the only one reading this (if he actually does). Others learn from what is said here, therefor the "point" is to educate others who aren't knowledgeable in the field (or who don't know Phil).
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| snipped-for-privacy@isp.com says...
| | <snip> | |> > What something is designed for, and what it can do in certain cases, are |> > not always the same thing. Then when manufacturers find out that their |> > product already cheaply does what customers want that could have been done |> > in a more expensive way to drive more revenue, they realise the golden |> > goose has escaped the pen and are trying to round it back in. |> . |> Yea, those manufacturers are really stupid. Just like Martzloff. And the |> IEEE. And the NIST. |> . |> > | Or perhaps you could use a device the Emerald book indicates might be |> > | effective. For houses that would be a UPS. But make sure the |> > | manufacturer says the UPS will protect against swells and overvoltage. |> > |> > This is exactly what I am describing. They want to sell something that |> > is way more expensive, rather than admit that something cheap can do the |> > same thing (though self-destructively). |> . |> You dismiss UPSs, which the IEEE Emerald book says may be effective, for |> plug-in suppressors which the Emerlad book does not recommend. |> |> You attack an electrical engineer that is a recognized expert. |> |> You ignore what I post. |> |> There isn?t much point in responding further. | | Actually, there is. Phil isn't the only one reading this (if he | actually does). Others learn from what is said here, therefor the | "point" is to educate others who aren't knowledgeable in the field | (or who don't know Phil).
It is very unlikely anyone else reads into these deep threads. Where people will become misinformed from your posts is at the top of the threads.
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says...

What a maroon! I know, you like it that way.
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krw wrote:

i still say he could trade places with Phill Allison, and no one would notice.
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snipped-for-privacy@earthlink.net says...

Well, Phil isn't quite as "colorful" as Phyllis.
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krw wrote:

He's only been online sine 1686, give him time. :(
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snipped-for-privacy@ipal.net wrote:

But what you are doing in the discussion is force fitting the MOV TVSS into protecting against events that it was not designed for. It's like insisting that your umbrella protect against the rain in a hurricane. It might keep the rain off briefly, before the wind blows it apart.
Ed
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| snipped-for-privacy@ipal.net wrote: |> On Fri, 29 Feb 2008 02:23:56 -0500 Michael A. Terrell
|> |>
|> |> |> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> |> | suppressor] failures is a temporary overvoltage, rather than an |> |> | unusually large surge." |> |> |> |> And these would not damage the TV? |> | |> | |> | No. Why do you think it would? if the surge suppresser clips at a |> | safe voltage to protect from spikes, it won't go any higher with a |> | overvoltage condition, but the MOV or other protection device quickly |> | overheats as it tries to maintain the proper voltage. If the line |> | voltage is high enough, it will trip the Breaker, or blow the fuse for |> | that AC circuit. The protective device can only dissipate a small |> | amount of heat before it self destructs. |> |> This was a discussion about a suggestion tha the MOV condunction voltage |> should be higher than now used (330V for 120V systems). He wants to |> raise that voltage to avoid certain situations causing TVSS failure so |> the protection against spikes (above 800V) is maintained longer. My |> position is that the swells as high as 565V RMS could in fact cause |> damage to the TV. Under his proposal, these would be be suppressed. |> I think that is a bad idea because these voltage swells really can do |> damage. |> | | But what you are doing in the discussion is force fitting | the MOV TVSS into protecting against events that it was not | designed for. It's like insisting that your umbrella | protect against the rain in a hurricane. It might keep | the rain off briefly, before the wind blows it apart.
That's a poor analogy.
The MOV based TVSS is most like to short circuit in a damaging event and cause the incoming breaker (the switch in the power strip, for example) to trip. The power strip might now be a usless hunk of metal and plastic, but the appliance to be protected is still protected for the duration.
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snipped-for-privacy@ipal.net wrote:

Ok, what specific TVSS models claim to be designed to do what you stated: protect against the overvoltage in the damaging event? Or are you just trolling?
Ed
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| snipped-for-privacy@ipal.net wrote:
|> |> On Fri, 29 Feb 2008 02:23:56 -0500 Michael A. Terrell
|> |> |>
|> |> |> |> |> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> |> |> | suppressor] failures is a temporary overvoltage, rather than an |> |> |> | unusually large surge." |> |> |> |> |> |> And these would not damage the TV? |> |> | |> |> | |> |> | No. Why do you think it would? if the surge suppresser clips at a |> |> | safe voltage to protect from spikes, it won't go any higher with a |> |> | overvoltage condition, but the MOV or other protection device quickly |> |> | overheats as it tries to maintain the proper voltage. If the line |> |> | voltage is high enough, it will trip the Breaker, or blow the fuse for |> |> | that AC circuit. The protective device can only dissipate a small |> |> | amount of heat before it self destructs. |> |> |> |> This was a discussion about a suggestion tha the MOV condunction voltage |> |> should be higher than now used (330V for 120V systems). He wants to |> |> raise that voltage to avoid certain situations causing TVSS failure so |> |> the protection against spikes (above 800V) is maintained longer. My |> |> position is that the swells as high as 565V RMS could in fact cause |> |> damage to the TV. Under his proposal, these would be be suppressed. |> |> I think that is a bad idea because these voltage swells really can do |> |> damage. |> |> |> | |> | But what you are doing in the discussion is force fitting |> | the MOV TVSS into protecting against events that it was not |> | designed for. It's like insisting that your umbrella |> | protect against the rain in a hurricane. It might keep |> | the rain off briefly, before the wind blows it apart. |> |> That's a poor analogy. |> |> The MOV based TVSS is most like to short circuit in a damaging event and |> cause the incoming breaker (the switch in the power strip, for example) |> to trip. The power strip might now be a usless hunk of metal and plastic, |> but the appliance to be protected is still protected for the duration. |> | | Ok, what specific TVSS models claim to be designed to do | what you stated: protect against the overvoltage in the | damaging event? Or are you just trolling?
Apparently most all of them ... either designed that way or just happen to operate that way. Otherwise the previously mentioned paper would not have needed to be written.
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snipped-for-privacy@ipal.net wrote:

I asked for specific models. Your answer does not contain a specific model. So you are trolling after all.
Ed
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| snipped-for-privacy@ipal.net wrote:
|> |> |> On Fri, 29 Feb 2008 02:23:56 -0500 Michael A. Terrell
|> |> |> |>
wrote: |> |> |> |> |> |> |> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> |> |> |> | suppressor] failures is a temporary overvoltage, rather than an |> |> |> |> | unusually large surge." |> |> |> |> |> |> |> |> And these would not damage the TV? |> |> |> | |> |> |> | |> |> |> | No. Why do you think it would? if the surge suppresser clips at a |> |> |> | safe voltage to protect from spikes, it won't go any higher with a |> |> |> | overvoltage condition, but the MOV or other protection device quickly |> |> |> | overheats as it tries to maintain the proper voltage. If the line |> |> |> | voltage is high enough, it will trip the Breaker, or blow the fuse for |> |> |> | that AC circuit. The protective device can only dissipate a small |> |> |> | amount of heat before it self destructs. |> |> |> |> |> |> This was a discussion about a suggestion tha the MOV condunction voltage |> |> |> should be higher than now used (330V for 120V systems). He wants to |> |> |> raise that voltage to avoid certain situations causing TVSS failure so |> |> |> the protection against spikes (above 800V) is maintained longer. My |> |> |> position is that the swells as high as 565V RMS could in fact cause |> |> |> damage to the TV. Under his proposal, these would be be suppressed. |> |> |> I think that is a bad idea because these voltage swells really can do |> |> |> damage. |> |> |> |> |> | |> |> | But what you are doing in the discussion is force fitting |> |> | the MOV TVSS into protecting against events that it was not |> |> | designed for. It's like insisting that your umbrella |> |> | protect against the rain in a hurricane. It might keep |> |> | the rain off briefly, before the wind blows it apart. |> |> |> |> That's a poor analogy. |> |> |> |> The MOV based TVSS is most like to short circuit in a damaging event and |> |> cause the incoming breaker (the switch in the power strip, for example) |> |> to trip. The power strip might now be a usless hunk of metal and plastic, |> |> but the appliance to be protected is still protected for the duration. |> |> |> | |> | Ok, what specific TVSS models claim to be designed to do |> | what you stated: protect against the overvoltage in the |> | damaging event? Or are you just trolling? |> |> Apparently most all of them ... either designed that way or just happen to |> operate that way. Otherwise the previously mentioned paper would not have |> needed to be written. |> | | I asked for specific models. Your answer does not | contain a specific model. So you are trolling after all.
Since you asked a trick question, I had to give a trick answer.
I detected the trick question. I just didn't admit it so I could see how far you would go with the answer I gave.
They don't CLAIM to provide such protection. So no, I cannot list a mode that CLAIMS this. They just HAPPEN to do so because of the fact that the MOV breakdown voltage is relatively low. So ultimately, it is your trick question that is the troll.
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snipped-for-privacy@ipal.net wrote:

Typical troll bullshit.
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On Sun, 02 Mar 2008 22:12:13 -0500 Michael A. Terrell
|> They don't CLAIM to provide such protection. So no, I cannot list a mode |> that CLAIMS this. They just HAPPEN to do so because of the fact that the |> MOV breakdown voltage is relatively low. So ultimately, it is your trick |> question that is the troll. | | | Typical troll bullshit.
This from someone that never directly addresses the technical issues when it is so much easier to just make a personal attack.
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snipped-for-privacy@ipal.net wrote:

What do you call your post other than an attack?
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On Mon, 03 Mar 2008 10:27:10 -0500 Michael A. Terrell
| snipped-for-privacy@ipal.net wrote: |> |> On Sun, 02 Mar 2008 22:12:13 -0500 Michael A. Terrell
|> |> |> They don't CLAIM to provide such protection. So no, I cannot list a mode |> |> that CLAIMS this. They just HAPPEN to do so because of the fact that the |> |> MOV breakdown voltage is relatively low. So ultimately, it is your trick |> |> question that is the troll. |> | |> | |> | Typical troll bullshit. |> |> This from someone that never directly addresses the technical issues when |> it is so much easier to just make a personal attack. | | | What do you call your post other than an attack?
A defense.
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