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#201
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
I think the UL requires only that the MOVs don't start a fire when
exposed to conditions which cause their break-down. *They don't rate their ability to function as "surge protectors". UL evaluates surge suppressors for fire, electric shock and personal injury hazards, and also measures and categorizes the devices for how much voltage they can "clamp," thus preventing excess voltage from passing through to electronic equipment. UL refers to this as a "suppressed voltage rating," with ranges from 330V (volts) to 4000V. Believe it or not, the lower the rating, the better the protection. Whatever surge suppression protection you're looking for, make sure the surge suppressor has been tested and Listed to the stringent requirements of UL 1449, the Standard for Transient Voltage Surge Suppressors. http://www.ul.com/consumers/surge.html http://ulstandardsinfonet.ul.com/toc...=s&fn=1449.toc |
#202
Posted to alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics,sci.electronics.repair
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Surge / Ground / Lightning
On May 6, 10:33*pm, "Michael A. Terrell"
wrote: w_tom wrote: On May 6, 12:08 pm, "Michael A. Terrell" wrote: * *Where did I say HOW was protected? It was my second week at that station, and the chief engineer took off on a long overdue vacation. If you would learn to read, rather than just do mindless rants you wouldn't look so stupid. *At that time the building had a UFER ground, and a three phase protection system at the meter CTs. That didn't prevent the damage, as you claim it should. * Lightning created damage. *Since Michael Terrell says it had an Ufer ground, that means grounding was properly installed and not corrupted? *Therefore the resulting damage proves, "Woe is me. Nothing can protect from lightning."? *Nonsense. * *That's it, _wacko_. *Use more misdirection. *It is YOU who claims that broadcast facilities sustain no damage from lightning strikes. * Damage was created by a surge. *A responsible human locates the defect in that protection system. *Michael Terrell was defeatist. *He 'knew' nothing can earthing lightning without damage. * *More _wacko_ lies, as expected. * Then Michael posts nonsense about other protectors so he need not admit this fact: MOVs are not used on telephone lines. *Why discuss fuses? *Fuses obviously are not for surge protection - when one has basic electrical knowledge. * Effective protectors (even gas discharge tubes - GDTs) earth direct lightning strikes and remain functional. * So why is Michael now discussing GDTs and fuses? * If you could read and comprehend you would know. *Sadly, you are too ignorant to understand what you read. *Michael has again been caught posting in error. *MOVs are not used for telephone line surge protection due to excessive capacitance. * *Liar. *You keep telling this lie, even though I posted links to two telephone cards using them, as well as the datasheets form one of many OEMs who make MOVs for Telecom service. *The stated capacitance is 480 pF *Tell us how that affects the bandwidth, when the line to the building has a higher capacitance. *This has long been common knowledge among those who post facts - not insults. * *gee, stop posting lies and insults, and learn the truth. *Nnoted and finally admitted by Michael is a reasons why so little lightning in the UK creates so much damage. * *Another blatant lie. I never mentioned anything to do with protection in the UK, _wacko_. *Master sockets are not even earthed as the equivlant NID is, routinely, in all North America. * *You didn't even look at that Epcos link, did you? *You can't admit that you are the biggest idiot and liar on USENET. *It doesn't really matter, everyone sees through your pathetic attempts to distort the truth. When that doesn't work, you fall back on lies and omissions to smear anyone you don't agree with. * Responsible people who suffer surge damage immediately search for the human failure that made damage possible. * *I did look. *What I found was large chunks of concrete blown away, and pieces of burnt rebar from a direct strike. *Search typically begins by looking for defects in the single point earth ground system. * *Now UFER is single point in a 10,000 Sq. Ft building? *Those who promote magic box plug-in protectors would not do this and must assume lightning damage cannot be avoided - a defeatist attitude. * *You are the one with an attitude. *Very little can be done to protect from a direct strike. Some towers have had entire sections vaporized from multiple strikes during a single storm, yet you continue to lie, by stating it can't happen. No where did I claim that plug-in protection was used. *This is another of your lies. *You ignored the fact that I had never even seen most of the building, because I was just hired. I was in the accounting office, right by the side door, and parking lot where I filled out the application. * *Here is the part you snipped, because you can't tell your ignorant lies, and leave it in: __________________________________________________ _________________________*_ * *Gee, _wacko_ you've never seen ANY modern business telephone equipment? *Gas tubes are fragile and very expensive. The protection isn't to save the privately owned telephones, it it to limit damage to the building. *Even that mid '60s 1A2 system had every output of the power supply fused to prevent a fire. Explain why an MOV's capacitance is high enough to affect a phone line. Never mind. *I have a Nitsuko/NEC DX2NA-32SYTEMEM KEY TELEPHONE SYSTEM in front of me, and every CO line in it has a MOV across the line. *Once more, you're preaching lies and using deceit to try to make others look bad. http://refurbishednitsuko.net/productInfo.aspx?productID=75978489-9ac.... is the Central Office line card for four telephone lines. See the black MOVs to the right of each pair of fuses? http://refurbishednitsuko.net/productInfo.aspx?productID=f5453e33-047.... is the card for four standard 2500 type telephones, or equivalent equipment. See the pairs of black MOVs over the blue connectors at the bottom of the screen? They are all japanese, with no brand markings. http://www.epcos.com/web/generator/Web/Sections/Publications/PDF/SIOV... is the Epcos MOV databook, with datasheets for Telecom applications. page 213 list the TELECOM MOV data. * *Every line into that studio building had a long distance call device diverter in the line that had MOV across the phone line. Every one of them survived the direct hit to the building and STL tower. That's more than can be said of your ability to use reason, and learn new things. * *You need to get your head out of 1920 and learn modern electronics. The one thing we learned today is that you don't know any more about Telecom that you do lightning protection, or reading comprehension. __________________________________________________ _________________________*_ --http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account:http://www.usenettools.net/ISP.htm LOL Haven't you seen W_ in action before? This is one of his standard rants repeated many times. According to W_ any damage from lightning or surges MUST be do to HUMAN failure. |
#204
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
VWWall wrote:
see original post http://www.ul.com/consumers/surge.html "The unpredictable nature of surges makes it difficult to suppress them; you never know when, how long or how powerful they will be. In some cases, a surge may have a higher energy level than the device can handle. When this happens, the surge suppressor may be damaged and lose its ability to provide protection against future surges." I'm happy to see that UL agrees! They don't seem to put any evaluation of this parameter, unless the "suppressed voltage rating" includes the Jules rating of the MOVs. This should read "Joules". See: http://en.wikipedia.org/wiki/Varistor for some useful information. -- Virg Wall, P.E. |
#205
Posted to alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics,sci.electronics.repair
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Surge / Ground / Lightning
wrote: LOL Haven't you seen W_ in action before? This is one of his standard rants repeated many times. According to W_ any damage from lightning or surges MUST be do to HUMAN failure. Yes, I've seen that, and more. That's why I refute his crap. If he isn't refuted, people who don't know any better will believe him. -- http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm |
#206
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
"w_tom" wrote in message
... On May 6, 2:45 pm, Sjouke Burry wrote: Can you trim W_tom with that?? Or is he incurable? He is incurable as long as others post outright lies and myths while denying what really provides surge protection. Now to discuss what is relevant. What's becoming more relevant here every day is your mental illness. . . . . along with your terrible OCD disadvantage, constantly referring to yourself in the third-person is pointing to a flourishing Depersonalization/Dissociative Identity Disorder. You can look it up. |
#207
Posted to alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics,sci.electronics.repair
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Surge / Ground / Lightning
Michael A. Terrell wrote:
wrote: LOL Haven't you seen W_ in action before? This is one of his standard rants repeated many times. According to W_ any damage from lightning or surges MUST be do to HUMAN failure. Yes, I've seen that, and more. That's why I refute his crap. If he isn't refuted, people who don't know any better will believe him. Just ask him about using a 3 1/2 digit VOM to check out those lousy ATX power supplies thet everyone is fostering on us. ;-) -- Virg Wall |
#208
Posted to alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics,sci.electronics.repair
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Surge / Ground / Lightning
wrote: Or his statements about how lightning strikes exactly once every 8 years. He's got a whole repertoire of these beauties. I no longer see his posts unless they are quoted in someone else's replies, as I filter all posts in alt.home.repair that come from googlegroups. I really don't miss him, as he just endlessly repeats the same garbage that he's been spewing for a decade on usenet. He's a complete kook. Not quite complete. He's still breathing. -- http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm |
#209
Posted to alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics,sci.electronics.repair
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Surge / Ground / Lightning
VWWall wrote: Michael A. Terrell wrote: wrote: LOL Haven't you seen W_ in action before? This is one of his standard rants repeated many times. According to W_ any damage from lightning or surges MUST be do to HUMAN failure. Yes, I've seen that, and more. That's why I refute his crap. If he isn't refuted, people who don't know any better will believe him. Just ask him about using a 3 1/2 digit VOM to check out those lousy ATX power supplies thet everyone is fostering on us. ;-) He's no better at choosing a meter than he is at thinking. -- http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm |
#210
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 7, 2:37*pm, VWWall wrote:
wrote: I think the UL requires only that the MOVs don't start a fire when exposed to conditions which cause their break-down. *They don't rate their ability to function as "surgeprotectors". UL evaluatessurgesuppressors for fire, electric shock and personal injury hazards, and also measures and categorizes the devices for how much voltage they can "clamp," thus preventing excess voltage from passing through to electronic equipment. UL refers to this as a "suppressed voltage rating," with ranges from 330V (volts) to 4000V. Believe it or not, the lower the rating, the better the protection. How can one find this rating for a particular device? Look for ul1449 330v or 400 for example, or surge voltage rating SVR 330v or Clamping Category 330v Whateversurgesuppression protection you're looking for, make sure thesurgesuppressor has been tested and Listed to the stringent requirements of UL 1449, the Standard for Transient VoltageSurge Suppressors. http://www.ul.com/consumers/surge.html "The unpredictable nature of surges makes it difficult to suppress them; you never know when, how long or how powerful they will be. In some cases, asurgemay have a higher energy level than the device can handle. When this happens, thesurgesuppressor may be damaged and lose its ability to provide protection against future surges." MOV’s and surge protectors are like tires on your car, the more you use them the shorter useful life, mistreat them, the shorter the useful life, too small or light weight the shorter the useful life. Ul 1449 certification take care of the too small or light weight. Proper selection for problem locations is the key to protection. I'm happy to see that UL agrees! *They don't seem to put any evaluation of this parameter, unless the "suppressed voltage rating" includes the Jules rating of the MOVs. Don’t pay attention to joules on surge protectors, no standard to measure, a better and recommended rating is “Peak Surge Current” the higher the better. http://ulstandardsinfonet.ul.com/toc...=s&fn=1449.toc Thanks for the reference. -- Virg Wall, P.E. |
#211
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On Mon, 05 May 2008 19:21:16 +0300, Tzortzakakis Dimitrios wrote:
Ï "Tantalust" Ýãñáøå óôï ìÞíõìá . .. "NB" wrote in message ... Who is W_TOM and why has he appeared in every single thread that has contained those keywords since 2001??? He an obsessive-compulsive disorder victim, apparently driven by some kind of bizarre fetish involving ground rods. What kind of ground rods? I prefer steel core, copper clad ones:-) I even have the special heavy hammer I saw one in one of the "Popular this-n-that" mags, that used a piece of copper pipe, with a hose fitting on the end. You point the pipe at the ground, turn on the hose, and the water digs its hole for it. Then, you can take the hose fitting off, cap the pipe, and have a pretty decent ground stake. Maybe it was one of the ham mags. Cheers! Rich |
#212
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 7, 7:27 am, wrote:
And as usual, W_'s statement taken at face value is wrong and/or misleading. A simple check of history shows Saddam did in fact have WMDs for years, because they were used in war and against his own people. Read Duelfer's report. Learn facts before posting. When David Kay's report said WMDs did not exist, then extremists had Kay's report withheld hoping that Charles Duelfer’s report would say otherwise. Instead, Duelfer’s report said what Kay's report said - and more. Those WMDs did not exist. trader should first learn before knowing. trader's constant bickering is directly traceable to knowledge with first learning facts. Another indication of that, his problem, are posts full of insults rather than technical facts. When will trader post a technical facts or citation? trader even denies what was well documented about Saddam's WMDs. No wonder he also posts insults that only Rush Limbaugh would be proud of. Meanwhile, a protector is only as effective as its earth ground which is why one 'whole house' protector is *routine* for effective household surge protection. Which is why responsible homeowners also inspect their primary surge protection: http://www.tvtower.com/fpl.html trader also denies this despite a long list of industry professionals that trader never bothered to learn from. Another professional standard contradicts naysayers such as trader. IEEE Green Book (IEEE Std 142) entitled 'Static and Lightning Protection Grounding': Lightning cannot be prevented; it can only be intercepted or diverted to a path which will, if well designed and constructed, not result in damage. Even this means is not positive, providing only 99.5-99.9% protection. ... Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per 30 years ... to one stroke per 6000 years ... Significantly effective is only one 'whole house' protector. Protector for about $1 per protected appliance. How much for the ineffective plug-in protector? $25 or $150 per protected appliance. Where does that plug-in protector even claim to protect from typically destructive surges? No plug-in manufacturer specification exists. It does not even claim to protect from the typically destructive sruge. IEEE is quite blunt about effective protection from a properly earthed 'whole house' protector. Unlike trader, I even provide numbers. trader never read industry standards. Unnecessary. trader automatically knows without first learning. |
#213
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 7, 2:37 pm, VWWall wrote:
How can one find this rating for a particular device? UL makes no effort to measure a protector's protective ability. In fact, protectors can completely fail during a UL certification test and still obtain UL approval. It failed without emitting sparks or flame; therefore UL approved. Approval may be obtained by undersizing MOV's thermal fuses so that a protector will disconnect MOVs faster during a surge; leave the appliance to fend for itself. Undersized surge protector simply disconnects faster to obtain UL1449 approval. How might it get that approval? Provide even less protection so as to not spit flame. Also required for UL approval is total number of joules. That says nothing about how many joules actually participate in protection. Typically, plug-in protectors use as little as 1/3rd and never more than 2/3rd of its joules for protection. If a protector is also for cable, telephone, network, etc, then that protector may use even less joules during protection. A 'whole house' protector uses all joules during all types of surges. What happens when more joules actually participate in protection? Well, doubling the numbers of 'used' joules typically increases a protector’s life expectancy by a factor of eight. As joules increase, the life expectancy of the protector increases exponentially. As joules increase, more energy gets dissipated in earth and less energy gets dissipated inside the protector. Increase joules to absorb less energy and to exponentially increase protector's life expectancy. Minimal 'whole house' protector for a home is 1000 joules and 50,000 amp surges. In locations where surges occur more frequently, a larger joule protector is installed. Increased joules means increases protector life expectancy. How effective are 'whole house' protectors? Well, a friend suffered when the 33,000+ volt transmission line fell upon his 4000 volt distribution line. Literally everyone powered from that B phase had electric meters explode up to 30 feet from their pans. Many had damage to plug-in protectors and to powered off appliances plugged into those protectors. But my friend suffered no damage, except to a meter that exploded off his building. He had a properly earthed 'whole house' protector. A protector is not rated to provide that protection. But properly installed protectors with sufficient joules will provide more protection than rated. Which protectors actually provide better protection? Products from a list of responsible manufacturers such as Intermatic, Square D, Siemens, Polyphaser, GE, Cutler-Hammer, Keison, and Leviton. Specifically not on that list are APC, Tripplite, Belkin, and Monster Cable. |
#214
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 7, 8:07 am, wrote:
According to W_, surge protection is impossible unless there is a direct and short connection to earth ground. Does the PC power supply come with a built-in earth ground? Again trader reads only what he wants to see. Surge protection without that short connection to earth ground is *ineffective*. trader, who understands propaganda in the Rush Limbaugh tradition, changes the message - uses the word 'impossible'. Misrepresenting reality is trader. PC power supply has no built-in earth ground. How do others know? They learned before knowing. For example, they read both front page EE Times articles entitled “Protecting Electrical Devices from Lightning Transients". trader did not. Those electrical concepts were too complex. trader knows rather than first learn technology. Had trader learned facts before posting, he would have read what IEEE Standards also said (and is posted elsewhere). Defined by the IEEE is effective protection - with numbers: Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per 30 years ... to one stroke per 6000 years ... What do 'whole house' protectors use? Enough MOVs so that protector is sufficiently sized. So that direct lightning strikes does not destroy the protector. What do MOVs need to provide effective connection? That short (ie ' less than 10 foot') connection to earth. What provides surge protection? Earth ground - where surge energy is harmlessly dissipated. What does the effective MOV do? Connects to earth so that surge energy gets dissipated harmlessly rather than destructively inside the building. What must those MOVs inside appliances do (and why did Apple stop using them after Apple II)? Those MOVs must somehow stop or absorb a surge that even three miles of sky could not stop. So few joules will somehow absorb all that energy. Such little devices will block what a sky could not? What happens when MOVs are too close to appliances and too far from earth ground? Page 42 Figure 8 from another IEEE citation - surge earthed 8000 volts destructively through the adjacent TV. Provides were numerous professional citations that say this. Where does trader even post technical numbers? He does not. trader is like most who recommend plug-in protectors. They need not first learn facts. They know. Their proof is by using insults – just like Rush Limbaugh. A protector is only as effective as its earth ground. |
#215
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
A protector is only as effective as its earth ground. And you are only as lucid as your drugs allow. -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida |
#216
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
In article , bud--
writes Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) My previous house still had its telephone earth rod and earth wire, though it had not been connected to the phone line for many years. -- (\__/) Bunny says NO to Windows Vista! (='.'=) http://www.cs.auckland.ac.nz/~pgut00...ista_cost.html (")_(") http://www.cypherpunks.to/~peter/vista.pdf |
#217
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
Also required for UL approval is total number of joules. That says nothing about how many joules actually participate in protection. Typically, plug-in protectors use as little as 1/3rd and never more than 2/3rd of its joules for protection. How does a protector decide how many of its joules to use? :-) Nick |
#218
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
... Surge protection without that short connection to earth ground is *ineffective*. Wrong, wrong, wrong (say it 3 times and it's true :-) Nick, ex-K3VZW, BSEE, MSEE, Senior Member, IEEE |
#219
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 7, 2:37 pm, VWWall wrote:
wrote: I think the UL requires only that the MOVs don't start a fire when exposed to conditions which cause their break-down. They don't rate their ability to function as "surgeprotectors". UL evaluatessurgesuppressors for fire, electric shock and personal injury hazards, and also measures and categorizes the devices for how much voltage they can "clamp," thus preventing excess voltage from passing through to electronic equipment. UL refers to this as a "suppressed voltage rating," with ranges from 330V (volts) to 4000V. Believe it or not, the lower the rating, the better the protection. How can one find this rating for a particular device? Look for ul1449 330v or 400 for example, or surge voltage rating SVR 330v or Clamping Category 330v Whateversurgesuppression protection you're looking for, make sure thesurgesuppressor has been tested and Listed to the stringent requirements of UL 1449, the Standard for Transient VoltageSurge Suppressors. http://www.ul.com/consumers/surge.html "The unpredictable nature of surges makes it difficult to suppress them; you never know when, how long or how powerful they will be. In some cases, asurgemay have a higher energy level than the device can handle. When this happens, thesurgesuppressor may be damaged and lose its ability to provide protection against future surges." MOV’s and surge protectors are like tires on your car, the more you use them the shorter useful life, mistreat them, the shorter the useful life, too small or light weight the shorter the useful life. Ul 1449 certification take care of the too small or light weight. Proper selection for problem locations is the key to protection. I'm happy to see that UL agrees! They don't seem to put any evaluation of this parameter, unless the "suppressed voltage rating" includes the Jules rating of the MOVs. Don’t pay attention to joules on surge protectors, no standard to measure, a better and recommended rating is “Peak Surge Current” the higher the better. |
#220
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
wrote:
On May 7, 2:37 pm, VWWall wrote: wrote: I think the UL requires only that the MOVs don't start a fire when exposed to conditions which cause their break-down. They don't rate their ability to function as "surgeprotectors". UL evaluatessurgesuppressors for fire, electric shock and personal injury hazards, and also measures and categorizes the devices for how much voltage they can "clamp," thus preventing excess voltage from passing through to electronic equipment. UL refers to this as a "suppressed voltage rating," with ranges from 330V (volts) to 4000V. Believe it or not, the lower the rating, the better the protection. That is a quote from UL. Contrast that with Martzloff: "The fact of the matter is that nowadays, most electronic appliances have an inherent immunity level of at least 600 V to 800 V, so that the clamping voltages of 330 V widely offered by TVSS [surge suppressor] manufacturers are really not necessary. Objective assessment of the situation leads to the conclusion that the 330 V clamping level, promoted by a few manufacturers, was encouraged by the promulgation of UL Std 1449, showing that voltage as the lowest in a series of possible clamping voltages for 120 V circuits. Thus was created the downward auction of 'lower is better' notwithstanding the objections raised by several researchers and well-informed manufacturers. One of the consequences of this downward auction can be premature ageing of TVSS that are called upon to carry surge currents as the result of relatively low transient voltages that would not put equipment in jeopardy." How can one find this rating for a particular device? Look for ul1449 330v or 400 for example, or surge voltage rating SVR 330v or Clamping Category 330v I believe it is required by UL to be on the package or literature. Whateversurgesuppression protection you're looking for, make sure thesurgesuppressor has been tested and Listed to the stringent requirements of UL 1449, the Standard for Transient VoltageSurge Suppressors. http://www.ul.com/consumers/surge.html "The unpredictable nature of surges makes it difficult to suppress them; you never know when, how long or how powerful they will be. In some cases, asurgemay have a higher energy level than the device can handle. When this happens, thesurgesuppressor may be damaged and lose its ability to provide protection against future surges." MOV’s and surge protectors are like tires on your car, the more you use them the shorter useful life, mistreat them, the shorter the useful life, too small or light weight the shorter the useful life. Ul 1449 certification take care of the too small or light weight. Proper selection for problem locations is the key to protection. I'm happy to see that UL agrees! They don't seem to put any evaluation of this parameter, unless the "suppressed voltage rating" includes the Jules rating of the MOVs. Don’t pay attention to joules on surge protectors, no standard to measure, a better and recommended rating is “Peak Surge Current” the higher the better. I would like to know the Joule ratings. The problem, as you say, is there is no standard way to measure the energy rating and some manufacturers apparently use questionable ratings. That has led some other reputable manufacturers, like SquareD, to not include Joule ratings. Peak surge current is directly related to the energy rating. w_'s recommended 50,000A surge current rating is way beyond what you will get at a service panel, but it represents a high energy rating which means long life. -- bud-- |
#221
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
On May 7, 2:37 pm, VWWall wrote: How can one find this rating for a particular device? UL makes no effort to measure a protector's protective ability. Cuttler Hammer says you are wrong. http://tinyurl.com/63594d Approval may be obtained by undersizing MOV's thermal fuses so that a protector will disconnect MOVs faster during a surge; leave the appliance to fend for itself. Of course that applies to service panel and plug-in suppressors. But CH says a suppressor has to have tested functionality (above). w_ just buys cheap Chinese knock offs, so his suppressors fail regularly. Also required for UL approval is total number of joules. Provide a cite. Why does your favored manufacturer SquareD not provide Joule ratings? A 'whole house' protector uses all joules during all types of surges. Depends on the surge. How effective are 'whole house' protectors? Well, a friend suffered when the 33,000+ volt transmission line fell upon his 4000 volt distribution line. Literally everyone powered from that B phase had electric meters explode up to 30 feet from their pans. Many had damage to plug-in protectors and to powered off appliances plugged into those protectors. But my friend suffered no damage, except to a meter that exploded off his building. He had a properly earthed 'whole house' protector. A protector is not rated to provide that protection. But properly installed protectors with sufficient joules will provide more protection than rated. Neither service panel or plug-in suppressors will survive extended overvoltage. It rapidly kills MOVs. w_ is using anecdotal evidence (with no cite) to suggest service panel suppressors protect from crossed power lines. More lunacy. Which protectors actually provide better protection? Products from a list of responsible manufacturers such as Intermatic, Square D, Siemens, Polyphaser, GE, Cutler-Hammer, Keison, and Leviton. Being responsible, they all make plug-in suppressors except SquareD. SquareD, for the ‘best’ service panel suppressor, says "electronic equipment may need additional protection by installing plug-in [suppressors] at the point of use." Still missing - a link to another lunatic that says plug-in suppressors are NOT effective. Still missing – answers to embarrassing 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 accurate information read the IEEE and NIST guides. Both say plug-in suppressors are effective. -- bud-- |
#222
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
VWWall wrote:
bud-- wrote: VWWall wrote: wrote: "New thermally enhanced MOVs help protect a wide variety of low-power systems against damage caused by over-current, over-temperature and over-voltage faults, including lightning strikes, electrostatic discharge (ESD) surges, loss of neutral, incorrect input voltage and power induction. I had a microwave oven that had a MOV across the 120V line ahead of the power switch. The other side of the 120/240 20A circuit supplied a refrigerator. The loss of the neutral applied a good part of the 240V across the MOV when the refrigerator attempted to start. The MOV didn't last long! It would probably have been OK on the load side of the switch. Using a MOV to protect against loss of neutral (in the article) is rather futile. Sustained overvoltage will rapidly kill them. Although if the protected load was across the MOV and a fuse was ahead of both protection may work. Would be interesting why the MOV was ahead of the switch. Good question. In the MW oven case, the switch was a relay controlled by the timer circuit. It was probably easier to locate the MOV at the line input. I have seen cases with a "blown" MOV and the circuit protector tripped. The MOV, if it tripped the protector, may have saved the following circuits from the over-voltage condition for a longer period of time. I haven't tried to calculate the conditions under which this would work. Normal MOV failure is by high current and overheating (as below). A fuse may provide protection. Plug-in suppressors likely use the heat as part of the disconnect. For overvoltage, the disconnect would have to survive the higher voltage. I know that refrigerators should be alone on a "home run" circuit, and neutrals shouldn't be connected with wire nuts, but that wasn't how it was! My only complaint with some plug-in protectors is that the MOVs are often much too small. I've also seen some with only a line-line MOV. As you know, MOVs lose their capacity each time a "spike" causes them to conduct. This reduces the remaining capability to handle "surges". You may already know all of this - MOVs are damaged by heat from energy dissipated in their clamping action. The defined end of life of a MOV is when the voltage that produces a 1mA current decreases 10%. At that point the MOV is still clamping the voltage across it. Further dissipation continues to lower the voltage until the MOV conducts at ‘normal’ voltages and goes into thermal runaway. For surge suppressors, UL required protection disconnects the MOV when it overheats. It should still be clamping at that point. The energy (Joule) rating is for a single event. If the individual hits are far below the rating, the cumulative energy rating is far above the single event rating. High ratings give longer life than you might expect. Service panel and plug-in suppressors do not protect by absorbing energy. But they absorb energy in the process of protecting. I would only buy one with fairly high ratings (which are readily available). True, but some are marketed as "surge protected" with minimal capacity. I've replaced the MOVs in several cheap multiple socket strips with higher rated MOVs from Radio Shack. UL, as far as I know, requires MOVs to be L-N, L-G, N-G. I thought that was the standard since the start, which w_ said was 1985. I think the UL requires only that the MOVs don't start a fire when exposed to conditions which cause their break-down. They don't rate their ability to function as "surge protectors". A Cuttler-Hammer tech note: http://tinyurl.com/63594d has some information on UL tests. Suppressors have to remain functional through an initial set of surges (20 surges - 6kv, 3kA). They can fail safely after that. (This sounds more like the service panel suppressor test.) -- bud-- |
#223
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
Mike Tomlinson wrote:
In article , bud-- writes Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) My previous house still had its telephone earth rod and earth wire, though it had not been connected to the phone line for many years. I am pretty sure we had a party line long ago when I was a kid. Wikipedia's reference to "20th century telephone systems" makes me feel even older. One side of the ringer is all that was connected to earth. Not clamping phone wires to earth is a major surge suppression flaw. It allows high voltage from phone to power wires (like at a modem), and increases the stress on a multiport plug-in suppressor. A service panel suppressor doesn't help the voltage difference at all. Surprising since the UK seems to be very good on electrical protection in general. -- bud-- |
#224
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 8, 10:52*am, bud-- wrote:
I would like to know the Joule ratings. The problem, as you say, is there is no standard way to measure the energy rating and some manufacturers apparently use questionable ratings. That has led some other reputable manufacturers, like SquareD, to not include Joule ratings. Here is a couple of nice article for evaluating SPD’s. Is the Joule rating of an SPD important? While conceptually an surge protection device (SPD) with a larger energy rating will be better, comparing SPD energy (Joule) ratings can be misleading. More reputable manufactures no longer provide energy ratings. The energy rating is the sum of surge current, surge duration, and SPD clamping voltage. In comparing two products, the lower rated device would be better if this was as a result of a lower clamping voltage, while the large energy device would be preferable if this was as a result of a larger surge current being used. There is no clear standard for SPD energy measurement, and manufacturers have been known to use long tail pulses to provide larger results. Additionally confusing this issue is the possibility that the rating is just the energy absorbed, diverted, or the sum of both. NEMA LS 1 by specific omission does not recommend the comparison of SPD’s energy ratings. Comparison of single shot surge ratings and let-through voltages is considered sufficient. http://www.nemasurge.com/help.html http://ecmweb.com/mag/electric_compa...d_performance/ http://www.control-concepts.com/pdfs/01_005.pdf http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf 2.5.1 Joule Rating |
#225
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
bud-- wrote:
Mike Tomlinson wrote: In article , bud-- writes Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) My previous house still had its telephone earth rod and earth wire, though it had not been connected to the phone line for many years. I am pretty sure we had a party line long ago when I was a kid. Wikipedia's reference to "20th century telephone systems" makes me feel even older. One side of the ringer is all that was connected to earth. Not clamping phone wires to earth is a major surge suppression flaw. It allows high voltage from phone to power wires (like at a modem), and increases the stress on a multiport plug-in suppressor. A service panel suppressor doesn't help the voltage difference at all. Surprising since the UK seems to be very good on electrical protection in general. I had a party line as a 10 year old. I used to screw with the other party if I heard them when I picked up the phone.. strange noises, etc. Of course I got caught, corporal punishment, etc. I think they used to ring between the red green for one party, yellow green for the other party, black green, etc. Eric |
#226
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
In article ,
says... bud-- wrote: Mike Tomlinson wrote: In article , bud-- writes Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) My previous house still had its telephone earth rod and earth wire, though it had not been connected to the phone line for many years. I am pretty sure we had a party line long ago when I was a kid. Wikipedia's reference to "20th century telephone systems" makes me feel even older. One side of the ringer is all that was connected to earth. Not clamping phone wires to earth is a major surge suppression flaw. It allows high voltage from phone to power wires (like at a modem), and increases the stress on a multiport plug-in suppressor. A service panel suppressor doesn't help the voltage difference at all. Surprising since the UK seems to be very good on electrical protection in general. I had a party line as a 10 year old. I used to screw with the other party if I heard them when I picked up the phone.. strange noises, etc. Of course I got caught, corporal punishment, etc. We had a party line when I was very young. ...until about '56, or so. Ma Bell had gotten rid of them in the area by '59. I think they used to ring between the red green for one party, yellow green for the other party, black green, etc. No, that would defeat the purpose of the party line. The ringers either had "distinctive ring" (once for Mabel, twice for Maude) or were frequency tuned. -- Keith |
#227
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 8, 1:07 pm, wrote:
Is the Joule rating of an SPD important? While conceptually an surge protection device (SPD) with a larger energy rating will be better, comparing SPD energy (Joule) ratings can be misleading. More reputable manufactures no longer provide energy ratings. The energy rating is the sum of surge current, surge duration, and SPD clamping voltage. In comparing two products, the lower rated device would be better if this was as a result of a lower clamping voltage, while the large energy device would be preferable if this was as a result of a larger surge current being used. There is no clear standard for SPD energy measurement, and manufacturers have been known to use long tail pulses to provide larger results. MOV manufacturers do not play the 'joules' games that some plug-in protector manufacturers play. Plug-in protector typically uses as little or less than 1/3rd and never more than 2/3rds of rated joules during protection. During some surges, a plug-in protector may use 0% of its joules because the massive surge voltage is same on all wires - as surge seeks earth ground destructively via electronics. No voltage between wires means the protector never sees any of the destructive surge - does nothing for protection. So how many joules does it really use? An effective 'whole house' protector uses 100% of its joules for all types of surges which is why 'whole house' protectors can routinely earth direct lightning strikes without damage - why these protectors suvive and absorb less energy due to an exponentially longer life expectancy. Joules that actually get used during each surge provide a ballpark measurement for a protector's life expectancy. Further numbers are in an above reply to VWWall on 7 May 2008. SVR, typically 330 or 400 volts, printed on the box, required by the UL, and more often called "let-through voltage". A vague number so that consumers can make ball park comparisons. No useful for making engineering decisions. A plug-in protector rated at 330 volts will start conducting at maybe 200 volts. When a larger surge occurs, it conducts at 900 volts. Protector rated at 330 volts conducts between 200 and 900 volts. What happens when conducting at or above 900 volts? MOV self destructs - vaporizes. Also called those 'scary pictures' - what every MOV manufacturers defines as unacceptable operation. So what does that SVR (threshold or let-through) voltage really measure? Discussed is a 70 SVR difference. Irrelevant since the difference between ineffective and proper earthing is thousands of volts. If not properly earthed, then even a tiny 100 amp surge puts that protector at something approaching 12,000 volts. 70 volts or even 330 volts is completely irrelevant. Properly routed ground wire (no sharp bends, etc) can make thousands of volts difference as described by so many professional citations. What defines protection? Quality of and connection to earth ground can make thousands of volts difference. Page 42 Figure 8 from Bud's IEEE citation. Will a 330 or 400 volt protector make any difference? Of course not. With either protector, that surge is still 8000 volts destructively finding earth ground through an adjacent TV. How to eliminate up to 12,000 volts? Shorten the 50 feet AC electric wire between protector and earth ground to zero feet. Bud posts that electronics contain internal protection of 600 or 800 volts. Intel ATX specs demand that internal protection exceed 1000 volts. Just another reason why 330 or 400 let-through volts is irrelevant. Relevant is 900 volts during a typically destructive surge on a 330 or 400 volt protector. "My surge protector sacrificed itself to save my computer". Reality. A protector was so grossly undersized that voltage exceeded 900 volts. MOV did what no MOV must do - vaporize. What protected that computer? Computer's internal protection protected the computer. But a naive computer assembler *knows* the protector provided protection. A myth promoted by grossly undersizing plug-in protectors. To be effective, a protector must earth a direct lightning strike and remain functional. Why argue over which jelly bean is prettier when the room will be engulfed by a flood. 70 volts difference in SVR is trivial when improper earthing can mean another 8000 or 12,000 volts during the typically destructive type of surge. |
#228
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
On May 8, 12:11 pm, bud-- wrote:
UL makes no effort to measure a protector's protective ability. Cuttler Hammer says you are wrong. http://tinyurl.com/63594d Again Bud misrepresents what professional say. Cutler-Hammer says: 2. Surge Test. Let through voltage tested at lower current than 1st edition. 10 kA (IEEE Cat C3) used for the first time, however, it was used only to see if products fail safely. Only tests a product for a safe failure – does not threaten human life. Does not measure the performance of protection. Same citation further states: 2. UL does not verify that the TVSS device will achieve the manufacturer's published surge current ratings. Of course not. That would be measuring a protector's protection abilities. UL does not measure protection - in direct contradiction to what Bud posts. A protector can completely fail during UL1449 testing and still be approved. UL only cares that is completely fails – provides no effective protection – without threatening human life. UL does determine functionality. Otherwise an empty box would be submitted by Bud’s peers as a surge protector and get UL1449 approval. A protector must demonstrate some protector function. But UL makes no effort to measure abilities of that protector. UL only tests that it functions like a protector and does not harm humans. Bud must deny those which is why his post again lies about what Cutler- Hammer, IEEE, NIST, and so many others say. Meanwhile, Bud repeatedly claims that protectors create fires because UL1449 was created in 1998. UL1449 was approved in 1987 as Cutler-Hammer also says. Again, Cutler-Hammer disagrees with what Bud posts. Numerous plug-in protectors after 1998 with UL approval still create a fire risk – the scary pictures: http://www.hanford.gov/rl/?page=556&parent=554 http://www.westwhitelandfire.com/Art...Protectors.pdf http://www.ddxg.net/old/surge_protectors.htm http://www.zerosurge.com/HTML/movs.html http://tinyurl.com/3x73ol http://www3.cw56.com/news/articles/local/BO63312/ Finally, Bud claims a plug-in protector protects from a surge that typically destroy appliances. 400 times Bud has been asked to provide those specs. He refuses because no plug-in manufacturer will claims what Bud posts. Bud lies about his own IEEE, NIST and Cutler- Hammer citations. Bud even claims that UL measures a protector's protection abilities. UL does not. UL addresses threats to human safety. Protector can completely fail during UL testing and still be approved as long as the protector does not spit flame during that failure. Bud provides not one manufacture spec that claims protection. Bud cannot provide what does not exist. No wonder Bud will also post insults He cannot dispute facts even from his IEEE, NIST, and Cutler- Hammer citations. A protector is only as effective as its earth ground. UL makes no effort to rate protection for each protector. |
#229
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
In article , bud--
writes Not clamping phone wires to earth is a major surge suppression flaw. It's simply not necessary in towns and cities in the UK. Occurrences of damage caused by surges on phone lines are practically unheard of. There are reports of damage caused by direct or nearly lightning strikes, but of course nothing is going to protect against that. Houses in villages and remote locations would probably benefit most from additional protection. You can be sure that critical installations (hospitals, data centres, etc.) will install additional protection. British Telecom fit NTE (network termination equipment), also known as a master socket, which does have surge arrestors built in, but they don't clamp to earth, they're just across the line: http://www.buzzhost.co.uk/nte5.php has a circuit diagram of the NTE, and an interesting photo of damage caused by a direct lightning strike further down the page (which, of course, none of w_'s equipment would have prevented.) An additional factor is that adding further surge protection devices can affect the line characteristics, causing ADSL sync speeds to drop. A service panel suppressor doesn't help the voltage difference at all. Obviously. Surprising since the UK seems to be very good on electrical protection in general. As I said in an earlier post, a calm, intelligent assessment (not w_'s level of hand-waving, gibbering hysteria) of each situation is needed before deciding on the level of protection required. It's clear that it's simply not needed for most UK domestic phone lines; this will have been borne out by years and years of experience, looking at the number of insurance claims, etc. I should think BT's attitude is that if the customer wishes to install additional protection after the demarc (NTE), that's up to them. In the end, It's all about assessing risk and mitigating it. I found this webpage rather amusing: http://www.satcure.co.uk/tech/phonesurge.htm but will leave it to others to comment -- (\__/) Bunny says NO to Windows Vista! (='.'=) http://www.cs.auckland.ac.nz/~pgut00...ista_cost.html (")_(") http://www.cypherpunks.to/~peter/vista.pdf |
#230
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
"Mike Tomlinson" wrote in message
... In article , bud-- writes Not clamping phone wires to earth is a major surge suppression flaw. It's simply not necessary in towns and cities in the UK. Occurrences of damage caused by surges on phone lines are practically unheard of. There are reports of damage caused by direct or nearly lightning strikes, but of course nothing is going to protect against that. Houses in villages and remote locations would probably benefit most from additional protection. You can be sure that critical installations (hospitals, data centres, etc.) will install additional protection. British Telecom fit NTE (network termination equipment), also known as a master socket, which does have surge arrestors built in, but they don't clamp to earth, they're just across the line: http://www.buzzhost.co.uk/nte5.php has a circuit diagram of the NTE, and an interesting photo of damage caused by a direct lightning strike further down the page (which, of course, none of w_'s equipment would have prevented.) An additional factor is that adding further surge protection devices can affect the line characteristics, causing ADSL sync speeds to drop. A service panel suppressor doesn't help the voltage difference at all. Obviously. Surprising since the UK seems to be very good on electrical protection in general. As I said in an earlier post, a calm, intelligent assessment (not w_'s level of hand-waving, gibbering hysteria) of each situation is needed before deciding on the level of protection required. It's clear that it's simply not needed for most UK domestic phone lines; this will have been borne out by years and years of experience, looking at the number of insurance claims, etc. I should think BT's attitude is that if the customer wishes to install additional protection after the demarc (NTE), that's up to them. In the end, It's all about assessing risk and mitigating it. I found this webpage rather amusing: http://www.satcure.co.uk/tech/phonesurge.htm but will leave it to others to comment -- (\__/) Bunny says NO to Windows Vista! (='.'=) http://www.cs.auckland.ac.nz/~pgut00...ista_cost.html (")_(") http://www.cypherpunks.to/~peter/vista.pdf Wow, it says phone lines there can have as much as 180 [ringing] volts on them, interesting. |
#231
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
On May 8, 12:11 pm, bud-- wrote: UL makes no effort to measure a protector's protective ability. Cuttler Hammer says you are wrong. URL deleted Again Bud misrepresents what professional say. Sorry I picked up the wrong URL. The correct one is http://tinyurl.com/5m3wrf UL does not measure protection - in direct contradiction to what Bud posts. Using the correct URL, the CH cite above says suppressors have to remain functional through an initial set of surges (20 surges - 6kv, 3kA). That is significant functionality. They can fail safely after that. (Although CH does not say it, I believe the test for plug-in suppressors is at a lower current.) A protector can completely fail during UL1449 testing and still be approved. It can fail after significant functionality (above) has been established. For instance when subjected to long overvoltage a suppressor can fail safely. Meanwhile, Bud repeatedly claims that protectors create fires because UL1449 was created in 1998. w_ is so stupid he still can’t figure out the difference between a creation date and a revision date. UL1449-2ed (1998) requires thermal disconnects. UL1449 was approved in 1987 as Cutler-Hammer also says. Again, Cutler-Hammer disagrees with what Bud posts. With minimal intelligence w_ could read in old link "UL1449(2nd edition 1996 [publication date])". In the new link, 1st sentence: "The Second Edition of UL1449 became effective August 17, 1998." Numerous plug-in protectors after 1998 with UL approval still create a fire risk – the scary pictures: Lacking valid technical arguments, w_ continues to lie about scary pictures. None of the links say a damaged suppressor even had a UL label. Still missing - a link to any source that says UL listed plug-in suppressors made after 1998 are a problem. A protector is only as effective as its earth ground. w_'s religious mantra will protect him from evil. Still missing - a link to another lunatic that says plug-in suppressors are NOT effective. Still missing – answers to embarrassing 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 reliable information read the IEEE and NIST guides. Both say plug-in suppressors are effective. -- bud-- |
#232
Posted to alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics
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Surge / Ground / Lightning
w_tom wrote:
Plug-in protector typically uses as little or less than 1/3rd and never more than 2/3rds of rated joules during protection. Depends on the surge that arrives. Like a service panel suppressor, buy one with adequate ratings. An effective 'whole house' protector uses 100% of its joules for all types of surges Depends on the surge that arrives. A plug-in protector rated at 330 volts will start conducting at maybe 200 volts. When a larger surge occurs, it conducts at 900 volts. Large surges can hit service panels so you might get 900V at the service. The significant impedance of a branch circuit for surges greatly limits the current that can reach a plug-in suppressor. Many sources recommend adding a plug-in suppressor at "sensitive" electronics to further limit the service panel let-through voltage. Bud posts that electronics contain internal protection of 600 or 800 volts. Intel ATX specs demand that internal protection exceed 1000 volts. bud quotes Martzloff who says 600-800V. Just another reason why 330 or 400 let-through volts is irrelevant. As usual, w_ can’t understand Martzloff. Voltage let-through is important to Martzloff because the lowest values cause suppressors to conduct on surges that are not damaging to connected equipment, which shortens the lifetime of the suppressor. "My surge protector sacrificed itself to save my computer". Reality. A protector was so grossly undersized that voltage exceeded 900 volts. In w_'s mind, plug-in suppressors have minuscule ratings, service panel suppressors have mega ratings. Plug-in suppressors are readily available with very high ratings for relatively low cost. And w_ only buys special MOVs that self destruct at 900V. All the others depend on energy absorbed. MOV did what no MOV must do - vaporize. w_ buys also only buys unlabeled Chinese suppressors that do not have the UL required thermal disconnect. Still can't find another lunatic that says plug-in suppressors are NOT effective? -- bud-- |
#233
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Surge / Ground / Lightning
krw wrote:
In article , says... Mike Tomlinson wrote: Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) I think they used to ring between the red green for one party, yellow green for the other party, black green, etc. No, that would defeat the purpose of the party line. The ringers either had "distinctive ring" (once for Mabel, twice for Maude) or were frequency tuned. They did frequency and distinctive rings. But for 2 parties you can ring red-to-ground for one and green-to-ground for the other. It is in Mike's Wikipedia link above. My recollection is black was ground and yellow was sometimes used for a light in the phone (red and green are phone wires). -- bud-- |
#234
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Surge / Ground / Lightning
In article ,
says... krw wrote: In article , says... Mike Tomlinson wrote: Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) I think they used to ring between the red green for one party, yellow green for the other party, black green, etc. No, that would defeat the purpose of the party line. The ringers either had "distinctive ring" (once for Mabel, twice for Maude) or were frequency tuned. They did frequency and distinctive rings. But for 2 parties you can ring red-to-ground for one and green-to-ground for the other. It is in Mike's Wikipedia link above. My recollection is black was ground and yellow was sometimes used for a light in the phone (red and green are phone wires). Princess phones used the yellow green pair for the dial light. A transformer was hidden somewhere in teh house to supply the power (IIRC, a standard 24VAC door bell transformer, but it's been a lot of years). -- Keith |
#235
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Surge / Ground / Lightning
krw wrote:
Princess phones used the yellow green pair for the dial light. A transformer was hidden somewhere in teh house to supply the power (IIRC, a standard 24VAC door bell transformer, but it's been a lot of years). The lamp was on yellow & black. Red & Green are the pair to the CO. -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida |
#236
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Surge / Ground / Lightning
In article krw writes:
Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Trace: individual.net 3POWAdBHT/AQLNg6QyObPgN2qBNF3foOsqw8tsoIJdTH9HWfec Cancel-Lock: sha1:aGa2E++HGN4b0KEf1TQhRkWJJts= User-Agent: MicroPlanet-Gravity/2.70.2067 Xref: shelby.stanford.edu alt.comp.hardware.pc-homebuilt:482039 alt.home.repair:656474 alt.tv.tech.hdtv:178799 sci.electronics.basics:272742 In article , says... krw wrote: In article , says... Mike Tomlinson wrote: Phone wires were clamped to ground before the 1960s? It was common to earth one leg of the incoming pair to either the house ground or to its own rod. An earth connection also allowed "party lines", where two houses could share one physical phone line pair, each house with its own number. Disadvantage was that both lines could not be used simultaneously. http://en.wikipedia.org/wiki/Party_line_(telephony) I think they used to ring between the red green for one party, yellow green for the other party, black green, etc. No, that would defeat the purpose of the party line. The ringers either had "distinctive ring" (once for Mabel, twice for Maude) or were frequency tuned. They did frequency and distinctive rings. But for 2 parties you can ring red-to-ground for one and green-to-ground for the other. It is in Mike's Wikipedia link above. My recollection is black was ground and yellow was sometimes used for a light in the phone (red and green are phone wires). Princess phones used the yellow green pair for the dial light. A transformer was hidden somewhere in teh house to supply the power (IIRC, a standard 24VAC door bell transformer, but it's been a lot of years). 6 volts as I recall. I had one of the transformers around ages ago, it may still be stashed somewhere. Not sure about the pair, though, since green/red is tip/ring of pair one, black/yellow is tip/ring of pair two. Putting the transformer between green and yellow would be putting the light current on the talk pair, which would be inviting hum on the line. More modern wiring uses: colors: main/stripe ----------- white/blue green tip 1 blue/white red ring 1 white/orange black tip 2 orange/white yellow ring 2 white/green tip 3 green/white ring 3 white/brown tip 4 brown/white ring 4 ( from http://www.ling.upenn.edu/~kurisuto/phone_wiring.html ) Similarly, I would question the reliability of ring on a single line referencing ground, since party lines tended to be out longer distances -- the ground resistivity would make it more difficult to get ring current to the phone(s). I think the differing ring frequency would make more sense, since mechanical resonance in the ringer provides a reasonable tuning mechanism. Alan |
#237
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Surge / Ground / Lightning
In article , Alan
writes Similarly, I would question the reliability of ring on a single line referencing ground, since party lines tended to be out longer distances -- the ground resistivity would make it more difficult to get ring current to the phone(s). It did work though. The mechanical bells in older phones in the UK had a lower impedance (500 ohm coils vs. 2000 ohm coils in newer phones), so the ringer would draw more current. The ringer was also two bells either side of a balanced clapper, so it took little to make it ring - the more current it was able to draw from the line, the louder it rang. I remember a neighbour with a party line whose phone had problems - calling her would give a ring tone in the earpiece, but she would claim that she had never heard the phone ring. Several visits from the GPO (as was BT) engineers found no fault, the phone always working when they visited. Eventually it was discovered that her party line was grounded via the waste pipe (lead pipe into a cast iron stack disappearing into the ground) of her cloakroom toilet, which was little used, and in the summer, when the ground dried out and the water in the toilet pan evaporated and ran low, the phone lost its earth and failed to ring. Flushing the toilet restored normal operation to the phone -- (\__/) Bunny says NO to Windows Vista! (='.'=) http://www.cs.auckland.ac.nz/~pgut00...ista_cost.html (")_(") http://www.cypherpunks.to/~peter/vista.pdf |
#238
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Surge / Ground / Lightning
Mike Tomlinson wrote: In article , Alan writes Similarly, I would question the reliability of ring on a single line referencing ground, since party lines tended to be out longer distances -- the ground resistivity would make it more difficult to get ring current to the phone(s). It did work though. The mechanical bells in older phones in the UK had a lower impedance (500 ohm coils vs. 2000 ohm coils in newer phones), so the ringer would draw more current. The ringer was also two bells either side of a balanced clapper, so it took little to make it ring - the more current it was able to draw from the line, the louder it rang. I remember a neighbour with a party line whose phone had problems - calling her would give a ring tone in the earpiece, but she would claim that she had never heard the phone ring. Several visits from the GPO (as was BT) engineers found no fault, the phone always working when they visited. Eventually it was discovered that her party line was grounded via the waste pipe (lead pipe into a cast iron stack disappearing into the ground) of her cloakroom toilet, which was little used, and in the summer, when the ground dried out and the water in the toilet pan evaporated and ran low, the phone lost its earth and failed to ring. Flushing the toilet restored normal operation to the phone Now THAT was _crappy_ phone service! -- http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm |
#239
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Surge / Ground / Lightning
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#240
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Surge / Ground / Lightning
krw wrote: In article , says... krw wrote: Princess phones used the yellow green pair for the dial light. A transformer was hidden somewhere in teh house to supply the power (IIRC, a standard 24VAC door bell transformer, but it's been a lot of years). The lamp was on yellow & black. Red & Green are the pair to the CO. slap! There I was typing, looking at bud-'s post and *STILL* got the wires crossed. I *shoulda* had a V8. No big deal. Do you remember that wall wart being the first one recalled for being a fire hazard? -- http://improve-usenet.org/index.html Use any search engine other than Google till they stop polluting USENET with porn and junk commercial SPAM If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm |
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