Surge Protectors
in [Repair]
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From: bud-- on 11 Jun 2010 13:13 westom wrote: > On Jun 9, 6:13 pm, Grant <o...(a)grrr.id.au> wrote: >> Do they fail to known state? Open or short? App. note showed a test >> rig with individually fused varistors, so I'm thinking they fail shorted? > > How does it fail? Open - sometimes explosively. They fail shorted. If not removed from a supply of power they may fracture. > A thermal fuse > disconnects its protector circuit. Leave the appliance connected to > that surge � to fend for itself. As pointed out previously, in a plug-in suppressor the protected load may be connected across the MOV and be disconnected with a failing MOV. If a service panel suppressor fails it leaves the appliance connected to surges � to fend for itself. > Earth > one 'whole house' protector so that energy dissipates harmlessly in > earth. A service panel suppressor is a good idea. But repeating from NIST surge guide: "Q - Will a surge protector installed at the service entrance be sufficient for the whole house? A - There are two answers to than question: Yes for one-link appliances [electronic equipment], No for two-link appliances [equipment connected to power AND phone or cable or....]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO - but that does not mean that a surge protector installed at the service entrance is useless." A service panel suppressor does not limit the voltage between power and cable/phone wires, which the NIST surge guide suggests is the cause of most equipment damage. > A protector is only as > effective as its earth ground. westom's religious mantra protects him from confusing thoughts - like plug-in suppressors work primarily by clamping, not earthing. Still missing - any reliable source that agrees with westom that plug-in suppressors are NOT effective. Still missing - answers to simple questions: - Why do the only 2 examples of protection in the IEEE guide use plug-in suppressors? - Why does the NIST guide says plug-in suppressors are "the easiest solution"? - Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in suppressor? - How would a service panel suppressor provide any protection in the IEEE example, page 42? - Why does the IEEE guide say for distant service points "the only effective way of protecting the equipment is to use a multiport [plug-in] protector"? - Why did Martzloff say in his paper "One solution. illustrated in this paper, is the insertion of a properly designed [multiport plug-in surge suppressor]"? - Why does Dr. Mansoor support multiport plug-in suppressors? For real science read the IEEE and NIST surge guides. Both say plug-in suppressors are effective. -- bud--
From: bud-- on 11 Jun 2010 13:27 Jim Yanik wrote: > zekfrivo(a)zekfrivolous.com (GregS) wrote in > news:hur1nd$df8$1(a)usenet01.srv.cis.pitt.edu: > >> In article <hur1gf$daq$1(a)usenet01.srv.cis.pitt.edu>, >> zekfrivo(a)zekfrivolous.com (GregS) wrote: >>> In article >>> <6bd56ef5-dfe7-4ef6-be9a-95a6fdca7e04(a)j4g2000yqh.googlegroups.com>, >>> westom <westom1(a)gmail.com> wrote: >>>> On Jun 10, 9:10 am, zekfr...(a)zekfrivolous.com (GregS) wrote: >>>>>> But, a little Tripplite portable laptop surpressor has a really >>>>> high rating in Joules. ?? >>>> How many hundred joules? Destructive surges are hundreds of >>>> thousands of joules. How does that Tripplite magically make all that >>>> energy disappear? It doesn't. That $3 power strip with some ten >>>> cent protector parts is selling for how much? Appreciate its >>>> purpose. >>>> >>>> Go to Lowes. Ask him for the Cutler-Hammer 'whole house' protector >>>> that costs less than $50. That protector (model CHSPMICRO) is for >>>> 50,000 amp surges. Don't take my word for it. Read the numeric >>>> specs. It will connect a direct lightning strike harmless to earth >>>> if connected to a breaker box that connects 'less than 10 feet' to >>>> earth ground. Massive energy dissipates harmlessly in earth. That >>>> Cutler- Hammer protector is required to protect the Tripplite. >>>> >>>> It is always about where energy dissipates. Why does that >>>> Tripplite >>>> numeric specifications not list protection from each type of surge - >>>> in numbers? Because it only claims to protect from surges that are >>>> typically not destructive. How does its hundreds of joules absorb >>>> surges that are hundreds of thousands of joules? Ask bud for those >>>> specs that claim protection from each type of surge. He will never >>>> provide those specs. >>>> >>>> A protector is only as effective as its earth ground. Which is why >>>> the Cutler-Hammer protector - about $1 per protected appliance - is >>>> also the superior solution >>> OK, I can't find it on their website. >>> >>> Read here. You say hundreds of thousands of Joules. >>> This one has 100KA at 840 Joules >> >> The little bitty Tripplite laptop protector is over a 1000 Joules. >> >>> This is twice the amperage as you state. >>> >>> http://www.drillspot.com/products/423212/Supco_SCMPLUS_Surge_Protector >>> Ratings are good. I wouldn't buy it because I have never heard of the manufacturer. I would like to explicitly see that it is UL1449 listed. "Meets UL" is a manufacturer claim and is not the same as UL listed (UL tested). The "UL 1449 Clamping Volts" have nothing to do with UL ratings - a red flag. >>> grge > > surge protectors don't ABSORB strike energy,they shunt it to > ground,providing a low resistance path to ground. > Instead of the energy passing thru your equipment on it's way to ground. That is probably appreciated by people here, but not in general. Neither service panel suppressors or plug-in suppressors protect by absorbing the surge. But they both absorb some energy in protecting. > > A higher Joules rating means the device absorbs less than a lower rated > device,and thus can divert more energy before IT blows up. The energy rating of a MOV - say 100 joules - is the singe event energy that can be absorbed by the MOV and put it at the defined end of life (but still functional). If the energy hits are less, say 10 joules, the cumulative energy rating will be significantly higher than 100 joules. If the energy hits are far lower, say 2 joules, the cumulative energy the MOV can absorb will be far larger than 100 joules. A very high rating means the suppressor is far less likely to fail. I don't expect my plug-in suppressors with high ratings to ever fail. > > One more limit is your home wiring;how much strike energy can those lines > carry? (to ground) > > and how good is the house ground? > If a house has a surge current to earth of 1,000A and a quite low resistance to earth of 10 ohms the system ground will rise to 10,000V above "absolute" earth potential. Martzloff has written "the impedance of the grounding system to `true earth' is far less important than the integrity of the bonding of the various parts of the grounding system." Make sure the phone and cable entrance protectors are connected with short wires to the ground at the power service. (Other systems, like satellite must also be connected.) If they are, the power and phone and cable wires can rise together. IMHO 'improving' the earthing is less important. High voltage between power and phone/cable wires is likely a major cause of equipment damage. -- bud--
From: westom on 11 Jun 2010 17:12 On Jun 11, 1:13 pm, bud-- <remove.budn...(a)isp.com> wrote: > As pointed out previously, in a plug-in suppressor the protected load > may be connected across the MOV and be disconnected with a failing MOV. That is not what your protectors do. Others can observe same. A power strip protector with the 'failed' light on still power appliances. Because the appliance is not disconnected when the protector circuit fails. A grossly undersized protector circuit disconnects as fast a possible to avoid fire. Leaves the appliance connected to the surge. Or view pictures from Zerosurge: http://www.zerosurge.com/HTML/movs.html They removed all MOVs. Failed light said the protector was still good. And power was still connected to appliance receptacles. Again, protector circuits disconnected and appliance remains connected to the surge. Bud's NIST citation discusses his protectors: > A very important point to keep in mind is that your surge protector will work by diverting > the surges to ground. The best surge protection in the world can be useless if grounding > is not done properly. "useless if grounding is not done properly" defines protectors that bud promotes. I am kind. I only called them ineffective. The NIST calls them "useless". A protector is only as effective as its earth ground. Every protection layer is only defined by THE item that does protection - earth ground. Earth one 'whole house' protector for secondary protection. Necessary even to protect protectors that bud promotes. Also inspect your primary protection system. Again, every protection layer is only defined by the earthing: http://www.tvtower.com/fpl.html bud will post incessently. And never provide one simple fact. Numeric specs that claim protection from each type of surge. He promotes high profit plug-in protectors. And still cannot cite even one manufacturer spec that lists protection from each type of surge. Of course not. Plug-in protectors are neither designed nor claim to provide protection from typically destructive surges. But when selling a $3 power strip with some ten cent protector parts for $25 or $150, then why tell the whole truth? Protection - as even defined in all his citations - is only as effective as its earth ground. Page 42 Figure 8 even shows the protector earthing a surge 8000 volts destructively through a TV because the protector is too close to appliances and too far from earth ground. Protection is always about where energy dissipates. How does his protector (hundreds of joules) absorb surges that are hundreds of thousands of joules? It doesn't. So he does not post numeric specs. Will not even discuss where energy dissipates. A protector is only as effective as its earth ground. How do those hundreds of joules make surges - hundreds of thousands of joules - just magically disappear? That answer is adjacent to those never provided numeric specs.
From: westom on 11 Jun 2010 17:20 On Jun 11, 1:27 pm, bud-- <remove.budn...(a)isp.com> wrote: > Martzloff has written "the impedance of the grounding system to `true > earth' is far less important than the integrity of the bonding of the > various parts of the grounding system." Martzloff what quite clear about what plug-in (point of connection) protectors can do to appliances. It was the very first conclusion in his 1994 paper - that discusses where energy dissipates: > Conclusion: > 1) Quantitative measurements in the Upside-Down house clearly show objectionable difference > in reference voltages. These occur even when or perhaps because, surge protective devices > are present at the point of connection of appliances. What is necessary to protect plug-in protectors? What is necessary so that plug-in protectors do not make appliance damage easier? Earthing. And a 'whole house' protector properly connected short (ie ' less than 10 feet') to single point earth ground. Where is surge energy dissipated when the effective 'whole house' protector is earthed? Harmlessly outside the building. Then objectionable differences do not exist in reference voltages. Why do telcos all over the world not waste money on plug-in protectors? They put their money where it does protection. Better earth grounds and a 'whole house' type protector that costs significantly less money. A protector is only as effective as its earth ground. Somehow that 1000 joules protector (that only used 333 and never more than 667 joules) will magically make hundreds of thousands of joules just magically disappear? I would say the same thing if my profit margins were that excessive.
From: westom on 11 Jun 2010 17:38
On Jun 11, 12:57 pm, bud-- <remove.budn...(a)isp.com> wrote: > Why aren't flying airplanes crashing every day when they are hit bylightning? Do they drag an earthing chain? Even his own citation contradicts what he posts. His own citaion, page 42 Figure 8 demonstrates the problem with plug-in protectors. Especially an earthed 'whole house' protector is missing. He cannot deny that. So he now wants to discuss airplanes.. Why is 'cloud to cloud' lightning relevant to protecting household appliances? It is not. Why are flying airplanes relevant? They are not. Bud's job is propaganda - to promote protectors that have no earthing. In deperation, he will discuss a flying airplane. Where are those numeric specs that claim protection from each type of surge. Bud cannot provide them for one simple reason. They can lie all they want in a sales brochure. But they cannot lie in the numeric specs. Bud cannot present numbers that do not exist. So now he wants to discuss flying airplanes. Read his own citations. The NIST defines bud's protectors: > The best surge protection in the world can be useless if grounding is not done properly. Numerous IEEE Standards say why bud's protectors do not claim protection in their numeric specs. From the IEEE Red Book: > In actual practice, lightning protection is achieve by the process of interception of lightning produced > surges, diverting them to ground, and by altering their associated wave shapes. How does it divert to earth when it does not connect to earth? Does it magically make energy disappear? Diverting (connectiong, bonding, shunting, switching) a surge to earth. Then the protector does, according to the NIST: > neither suppress nor arrest a surge, but simply divert it to ground, where it can do no harm. A protector is only as effective as its earth ground. So bud wants to discuss airplanes to avoid reality. Where are those manufacturer specs that claim protection from each type of surge? NIST and IEEE say why bud cannot provide them. A protector is only as effective as its earth ground. |