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Post by westom on Sept 5, 2016 15:03:06 GMT -5
Can you give more details on how much suppression and how it works? Useful answers are found in specification numbers. A protector adjacent to any appliance must either 'block' or 'absorb' a surge. How does its 2 cm part block what three miles of sky cannot? It doesn't. How does its hundreds or thousand joules 'absorb' a surge that is hundreds of thousands of joules? It doesn't. Why do so many 'love' their near zero joule protector? A potentially destructive surges occurs maybe once every seven years. Clearly is must be doing something when it never did anything. Some even confuse a blackout (that causes no damage) with a surge. Then credit that expensive protector. Protection is defined by what harmlessly dissipated hundreds of thousands of joules. No plug-in box claims to do that or will even discuss it. All appliances already have robust protection. Often a surge too tiny to overwhelm that protection can also destroy a near zero plug-in protector. Undersizing gets naive consumers to recommend that expensive protector. No protector should every fail catastrophically. Sacrificial protection is an urban myth. An effective protector earths direct lightning strikes without damage. Remains functional for decades. This superior solution (proven by over 100 years of science and experience) costs about $1 per protected appliance. And it little known by those educated by advertising. More spec numbers. A direct lightning strike can be 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. Unlike plug-in protectors, it is designed to protect from all types of surges including a direct lightning strike. Even necessary to protect plug-in protectors. So as to not fail catastrophically (ie undersized as reported by that protector light), then plug-in protectors should only be used in conjunction with a properly earthed 'whole house' protector. If that light ever reports a failure, then only a thermal fuse was averting a house fire. Any protector whose light indicates a failure was only one step away from harming human life. Protection is always about where hundreds of thousands of joules dissipate. No protector does that - not even a 'whole house' protector. Effective protectors are connecting devices to what actually does protection - single point earth ground. A surge connected low impedance (ie less than 10 feet) to earth need not be inside hunting for earth ground destructively via appliances. Then robust protection inside all appliances is not overwhelmed. Protectors only do something useful when the solution connects surges (including direct lightning strikes) to single point earth ground. Best protection on TV cable is a hardwire connected low impedance (ie wire has no sharp bends) to earth where it enters the structure. No protector required. That protection installed for free. Phones cannot connect direct to earth. So your telco installs a 'whole house' protector (for free) to do what that hardwire does better. That effective protector connects low impedance (ie hardwire not inside metallic conduit) to single point ground. What is not in any protector from Tripplite, APC, Panamax, or Monster? A low impedance connection to earth. Those protectors do not claim to protect from destructive surges. Again, read spec numbers. How many joules does it claim to absorb? A $3 power strip with ten cent parts costs $25 or $85? Those are profit centers; not effective protection. Why no discussion of THE most critical item in every protection system: earth ground? It does not even claim protection from destructive surges. It is protection of profit margins - and from surges too tiny to overwhelm existing protection inside all appliances. A useful answer references above and other specification numbers. Specification numbers (and many professional organizations) are quite clear what defines protection - single point earth ground. A protector is only as effective as its earth ground.
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Post by westom on Sept 5, 2016 15:11:15 GMT -5
When you say you've never seen <119v or >121v, is that at the output of the Panamax? If so, that's understandable as they may smooth out dips/surges. I know my APC does. If however, you're getting those voltages out of the wall, then you're very lucky. Even switching actions of refrigerators, washers, dryers etc. can cause larger deviations. Incandescent bulbs can dim to 50% intensity. Or double in brightness. Voltage variations that large are perfectly ideal voltages for all electronics. Furthermore, 120 volts can rise to 300 volts. And plug-in protectors (ie APC, Panamax, Tripplite) will ignore it - do nothing. Again, read its specification numbers. If it adjusts voltages, then specification numbers say so. No numbers exist because that voltage compensation is promoted by hearsay. If incandescent bulbs are changing intensity that much, then motorized appliances are at risk. So a utility will either provide sufficient voltage; or intentionally create a blackout. To protect what is at risk - motorized appliances - ie refrigerator, central air. If anything needs protection, it is what is at risk - ie dishwasher, washing machine. If Panamax or APC does what was only speculated, then those products must be on every refrigerator and furnace. And not needed on any electronics.
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Post by vneal on Sept 5, 2016 16:46:07 GMT -5
furman
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Post by Loop 7 on Sept 5, 2016 18:28:57 GMT -5
Our CMX-2 and CMX-6 are noise filters; they are not surge suppressors. Just took advantage of the sale and ordered a CMX-2.
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Post by Boomzilla on Sept 5, 2016 18:44:47 GMT -5
Pros use this one (but they can afford to...) Furman P-1800 AR
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Post by Loop 7 on Sept 5, 2016 19:20:25 GMT -5
Pros use this one (but they can afford to...) Furman P-1800 AR Spendy. If my budget were unlimited, I would either get the Furman or look into PS Audio's solutions.
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Post by TempTag on Sept 5, 2016 19:35:05 GMT -5
This one is pretty inexpensive for a model that includes an automatic voltage regulator but I found it somewhat noisy when nearby (can hear hum and clicks when too close to it) so it works better when equipment is in another area - I assume the more expensive conditioner/AVRs like the Furman are quieter? Tripp Lite 2400
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hemster
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Post by hemster on Sept 5, 2016 20:29:46 GMT -5
When you say you've never seen <119v or >121v, is that at the output of the Panamax? If so, that's understandable as they may smooth out dips/surges. I know my APC does. If however, you're getting those voltages out of the wall, then you're very lucky. Even switching actions of refrigerators, washers, dryers etc. can cause larger deviations. Incandescent bulbs can dim to 50% intensity. Or double in brightness. Voltage variations that large are perfectly ideal voltages for all electronics. Furthermore, 120 volts can rise to 300 volts. And plug-in protectors (ie APC, Panamax, Tripplite) will ignore it - do nothing. Again, read its specification numbers. If it adjusts voltages, then specification numbers say so. No numbers exist because that voltage compensation is promoted by hearsay. If incandescent bulbs are changing intensity that much, then motorized appliances are at risk. So a utility will either provide sufficient voltage; or intentionally create a blackout. To protect what is at risk - motorized appliances - ie refrigerator, central air. If anything needs protection, it is what is at risk - ie dishwasher, washing machine. If Panamax or APC does what was only speculated, then those products must be on every refrigerator and furnace. And not needed on any electronics. To confirm the readings on my APC, I measured the input voltage at 129v and output at 120v. I have also seen <120v input but exactly 120v output. Likely the electronics may be fine (performance likely degraded) with such small deviations but I prefer a steady diet of exactly120v. I live in the lightning capital of the world and have suffered hits to very near areas. I lost my garage door opener, eye sensors at the doors, all doors and window sensors as well as the control panel of my security system. Ditto for 2 A/C compressors. Microwave gone. Refrigerator made it. But none of my great plugged into the APC was affected. A cable TV box plugged into the same outlet died. Coincidence? Hmm. APC reimburse if one loses equipment. I haven't needed to call them for that.
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Post by westom on Sept 6, 2016 9:52:06 GMT -5
Coincidence? Hmm. APC reimburse if one loses equipment. I haven't needed to call them for that. Do they? Learn what so many discovered the hard way. APC warranty has numerous exemptions. They need not honor that warranty. Furthermore, products with a biggest (hyped) warranty are lesser products. A lesson learned in free markets. After all, GM cars have a best warranty. That proves Chevys are superior to Honda and Toyota? Please learn what defines the product - its specifications - not its warranty. No plug-in protector claims to provide that protection. As in none. Then Steve Uhrig in "UPS for computer and TV" explains his warranty experience: Or Lee Koo in "Do surge protectors merely give us a false sense of security?": You had damage because you failed to earth that surge BEFORE it entered. That surge selected which appliances made a better connection to earth - and destroyed only them. Power strip did nothing - as its spec numbers said it would do. We all learned observation alone is called junk science. Classic examples in elementary school science included spontaneous reproduction. And bread breeds maggots. In both cases, observation was the source of outright lies. If your protector did anything, then its spec numbers said it would provide that protection. Even its spec numbers do not make that claim. Somehow only observation is now prove? When did that happen? Some appliances (ie garage door opener) were destroyed while protecting other appliances (ie refrigerator). Surge need not pass destructively through a refrigerator when a garage door opener makes a better path. Superior protection already inside an appliance connected to a near zero joule APC also was not overwhelmed. Some other appliance made a better connection to earth. Learn that reality. Then observations become junk science. No reason exists to believe an APC did anything. APC does not even claim it does that protection. Worse, you actually believe its warranty says more than spec numbers? Please. That expensive APC has a protector circuit also found in a power strip selling in Walmart for $10 - without a fictitious warranty. Same circuit is better due to a warranty they need not even honor? For over 100 years, proven protection has existed that you failed to implement. Proven protection costs about $1 per protected appliance. How much did you spend for an APC with near zero joules and a bogus warranty? $25? $60? Why spend so much for so little protection? We all learned this in elementary school science. Conclusions from observation are classic junk science. That APC did and still is not effective IF a 'whole house' solution does not exist. It can even make damage easier. Why did APC recently announce that some 15 million APC protectors must be removed immediately? Fire. Another problem with near zero joule protectors. But somehow you know it is better because it has a warranty - chock full of exemptions. Same applies to a fear of voltage variation. Base only in emotion - not based in facts and well proven reality. Those near zero voltage variations are called ideal power - once facts and numbers are learned. How often do your light bulbs dim to 50% intensity? Ideal power for appliances but a great concern for human safety. Better is to fix a human safety threat - not cure its symptoms with a magic box from APC.
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Post by monkumonku on Sept 6, 2016 10:03:51 GMT -5
Coincidence? Hmm. APC reimburse if one loses equipment. I haven't needed to call them for that. Do they? Learn what so many discovered the hard way. APC warranty has numerous exemptions. They need not honor that warranty. Furthermore, products with a biggest (hyped) warranty are lesser products. A lesson learned in free markets. After all, GM cars have a best warranty. That proves Chevys are superior to Honda and Toyota? Please learn what defines the product - its specifications - not its warranty. No plug-in protector claims to provide that protection. As in none. Then Steve Uhrig in "UPS for computer and TV" explains his warranty experience: Or Lee Koo in "Do surge protectors merely give us a false sense of security?": You had damage because you failed to earth that surge BEFORE it entered. That surge selected which appliances made a better connection to earth - and destroyed only them. Power strip did nothing - as its spec numbers said it would do. We all learned observation alone is called junk science. Classic examples in elementary school science included spontaneous reproduction. And bread breeds maggots. In both cases, observation was the source of outright lies. If your protector did anything, then its spec numbers said it would provide that protection. Even its spec numbers do not make that claim. Somehow only observation is now prove? When did that happen? Some appliances (ie garage door opener) were destroyed while protecting other appliances (ie refrigerator). Surge need not pass destructively through a refrigerator when a garage door opener makes a better path. Superior protection already inside an appliance connected to a near zero joule APC also was not overwhelmed. Some other appliance made a better connection to earth. Learn that reality. Then observations become junk science. No reason exists to believe an APC did anything. APC does not even claim it does that protection. Worse, you actually believe its warranty says more than spec numbers? Please. That expensive APC has a protector circuit also found in a power strip selling in Walmart for $10 - without a fictitious warranty. Same circuit is better due to a warranty they need not even honor? For over 100 years, proven protection has existed that you failed to implement. Proven protection costs about $1 per protected appliance. How much did you spend for an APC with near zero joules and a bogus warranty? $25? $60? Why spend so much for so little protection? We all learned this in elementary school science. Conclusions from observation are classic junk science. That APC did and still is not effective IF a 'whole house' solution does not exist. It can even make damage easier. Why did APC recently announce that some 15 million APC protectors must be removed immediately? Fire. Another problem with near zero joule protectors. But somehow you know it is better because it has a warranty - chock full of exemptions. Same applies to a fear of voltage variation. Base only in emotion - not based in facts and well proven reality. Those near zero voltage variations are called ideal power - once facts and numbers are learned. How often do your light bulbs dim to 50% intensity? Ideal power for appliances but a great concern for human safety. Better is to fix a human safety threat - not cure its symptoms with a magic box from APC. So lemme ask you something. What is your opinion of the more expensive products, such as the Furman that was mentioned earlier in this thread? Is spending the hundreds and thousands of dollars on these more "elite" sort of products, including those that are power conditioners, similarly a waste of time? If I understand you correctly, all of these surge suppression devices are not necessary because our appliances already are sufficient. You mention "proven protection costs about $1 per protected appliance." What is that?
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Post by westom on Sept 6, 2016 10:08:21 GMT -5
But none of my great plugged into the APC was affected. A cable TV box plugged into the same outlet died. Learn how that APC protector circuit works. MOVs connected to attached appliances in the same way MOVs attach to any appliance on that duplex receptacle. If MOVs protected APC powered gear, then it also protected the cable box plugged into a same receptacle. Why were some 'protected' appliances undamaged and another (cable box) damaged? Both connected same to same MOVs. It was explained repeatedly. An incoming surge to everything selected only some (in this case one) items to connect to earth. Obviously, a best connection to earth was via a TV cable (that is required to have best surge protection at the service entrance). Since cable is a best connection to earth, then a TV cable box was destroyed protecting the APC and other adjacent appliances. By learning how surges work, then conclusions only based in observation quickly become junk science. Did you know TV cable already has best protection? Did you know that some appliances that make a better connection to that earth ground can be destroyed protecting other appliances? Protection is always about how a surge connects to earth. As in always. Cable TV box did the protection. Only wild speculation assumed an APC did anything useful. That cable TV box even protected a near zero joule APC - once we include how surges do damage. Did you know about best protection installed for free by the cable company? Why not? Some damaged appliances protected others. Near zero joules in an APC were protected by a TV cable box. Been doing this for a long time.
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KeithL
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Post by KeithL on Sept 6, 2016 10:13:01 GMT -5
SURGE SUPPRESSORS that use MOVs can fail over time..... grounding repeated surges stresses the MOVs and eventually they fail. (The MOVs may actually burn or shatter into fragments.)
The way they work is to attempt to clamp the voltage at a certain point - they do their best to short current to ground to keep the voltage from rising above that value. As Westom noted, a typical clamping value for a "125 V surge suppressor" is about 300V. (The "normal peak value" - the highest point on the sine wave - on a "125 V line" is about +/- 175V.) MOVs are usually rated as being able to ground a certain maximum amount of current, and in terms of how many "incidents" of a given power level they can survive before their performance falls below some minimum. MOST low-cost (under $100) surge suppressors fall into this category (APC, Tripplite, etc). Some other types, like series suppressors, and grounding types that use devices other than MOVs, may not wear out at all... Others may be rated for a single use, and some even offer replaceable "cartridges" that you change after they've experienced a heavy surge. This is entirely different than a POWER REGULATOR (any device that shows the mains voltage, and then adjusts the output voltage to remain constant when that mains voltage varies, is a regulator). In general, a regulator doesn't wear out from use.... however, as with most complex electronic devices, it can fail for other reasons. (However, correcting minor fluctuations shouldn't cause "excessive wear" of any kind.... ) Note that many regulators ALSO contain surge suppressors and/or power filters (intended to protect both your other equipment and the regulator itself from surges). (However, a regulator is the more expensive device by far, so a low cost surge suppressor isn't very likely to include one.) Also note that motor-driven appliances are often damaged by "brown out" conditions.... If the voltage drops too LOW they can burn out - either because they draw excessive current because the motor is running at the wrong speed, or because their integral cooling fan doesn't work at the lower voltage. I assume modern appliances are more tolerant of this, but it was a notorious cause of death for early air conditioners and refrigerators in particular. Also note that incandescent bulbs often burn out from surges (they get very bright - then they die). However, modern "electronic" bulbs are, on average, much less likely to be damaged by them. (And most modern consumer electronics, including our products, aren't especially sensitive to them either.) Incandescent bulbs can dim to 50% intensity. Or double in brightness. Voltage variations that large are perfectly ideal voltages for all electronics. Furthermore, 120 volts can rise to 300 volts. And plug-in protectors (ie APC, Panamax, Tripplite) will ignore it - do nothing. Again, read its specification numbers. If it adjusts voltages, then specification numbers say so. No numbers exist because that voltage compensation is promoted by hearsay. If incandescent bulbs are changing intensity that much, then motorized appliances are at risk. So a utility will either provide sufficient voltage; or intentionally create a blackout. To protect what is at risk - motorized appliances - ie refrigerator, central air. If anything needs protection, it is what is at risk - ie dishwasher, washing machine. If Panamax or APC does what was only speculated, then those products must be on every refrigerator and furnace. And not needed on any electronics. To confirm the readings on my APC, I measured the input voltage at 129v and output at 120v. I have also seen <120v input but exactly 120v output. Likely the electronics may be fine (performance likely degraded) with such small deviations but I prefer a steady diet of exactly120v. I live in the lightning capital of the world and have suffered hits to very near areas. I lost my garage door opener, eye sensors at the doors, all doors and window sensors as well as the control panel of my security system. Ditto for 2 A/C compressors. Microwave gone. Refrigerator made it. But none of my great plugged into the APC was affected. A cable TV box plugged into the same outlet died. Coincidence? Hmm. APC reimburse if one loses equipment. I haven't needed to call them for that.
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Post by westom on Sept 6, 2016 10:32:10 GMT -5
What is your opinion of the more expensive products, such as the Furman that was mentioned earlier in this thread? Is spending the hundreds and thousands of dollars on these more "elite" sort of products, including those that are power conditioners, similarly a waste of time? First, Monster once sold speaker cables with ends marked for speaker and amp. Monster said reversing cables subverted sound quality. Some bought those cables and could actually hear a difference. Monster sold $7 speaker cables for $70. Junk science is alive and well. Where was one spec number that said those speaker cables did anything special? Never existed making scams easy. Always demand numbers and the reasons why. Show me numbers that define what a Furman does. I tie knots in power cords. Those are also power conditioners - as long as we ignore numbers. Knots do filter noise. Near zero filters. But they do filter. That proves knots are ideal power conditioners. State what a Furman does and show me numbers that quantify that feature. No numbers is how junk science (and Monster speaker cables) get promoted. Second, I never said appliances have sufficient protection. All appliances have 'robust' protection (superior to what that APC claims to do). Your concern is anomalies that can overwhelm that protection. Nothing on its power cord will provide that protection. Some numbers (that expensive Furmans must address to claim hardware protection). Destructive transients can be hundreds of thousand of joules. If on a power cord, a Furman, et al must either 'block' or 'absorb' that energy. Where is this magic part that will 'block' what three miles of sky cannot? Does not exist. How many joules does that Furman (or APC) claim to 'absorb'? Hundreds? A thousand? What happens to hundreds of thousands of joules. Informed homeowners do what was done over 100 years ago to even have direct lightning strikes without damage. Properly earthed 'whole house' protector means hundreds of thousands of joules dissipate harmlessly outside. Then robust protection already inside every appliance (even dishwasher and furnace) is not overwhelmed. Never assume a magic box is a solution. No protector does protection. That 'whole house' protector (like a protector installed for free on TV cable) must make a low impedance (ie less than 10 foot) connection to what actually does protection: single point earth ground. That superior solution costs about $1 per protected appliance. How much was a Furman? Whose profit margins were more obscene - Furman's or Monster's speaker cables? Scams work when we ignore what was taught in elementary school science about spontaneous reproduction and maggots bred by bread. Junk science is so easy when a consumer ignores facts and numbers.
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Post by KeithL on Sept 6, 2016 10:43:24 GMT -5
In terms of absolute damage protection, I rather prefer series mode surge suppressors. Rather than shunt the surge to ground, they block it, forcing it to find another path to ground.... Because of the way they work, they are eventually limited by the voltage rise on the line, but NOT by the amount of current in the surge. This works especially well in situations where a line surge is caused by a nearby lightning strike to the power grid (which is common in residential neighborhoods). However, series mode surge suppressors do have a few drawbacks and limitations: 1) A 20 amp series mode surge suppressor costs about $200 (whole house models cost MUCH more). 2) They tend to be very large and very heavy (my 20 amp one is the size of a double-brick and weighs about ten pounds). 3) They are designed SPECIFICALLY to block very short surges; they do nothing to prevent or limit more gradual fluctuations and rises. (They're great for nearby lightning strikes, but totally useless if the voltage supplied by your power company simply isn't steady.) 4) They actually increase the supply impedance of your power line slightly (more or less equivalent to making your line cord a few feet longer). The two biggest vendors that I am aware of are Brick Wall and SurgeX (I use Brick Wall models at home) www.brickwall.com/pages/no-failures
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Post by copperpipe on Sept 6, 2016 11:17:02 GMT -5
Destructive transients can be hundreds of thousand of joules. If on a power cord, a Furman, et al must either 'block' or 'absorb' that energy. Where is this magic part that will 'block' what three miles of sky cannot? Does not exist. How many joules does that Furman (or APC) claim to 'absorb'? Hundreds? A thousand? What happens to hundreds of thousands of joules. I'm a total layman here. I always assumed the surge protectors worked by opening the circuit; like flipping a switch open, or unplugging a wire from the wall plug, I just imagined there was some fancy circuitry in there that had the same effect. So it doesn't absorb the energy, it simply removes the appliance from the circuit. Is that wrong? And are you suggesting that a properly grounded house is sufficient?
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hemster
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Post by hemster on Sept 6, 2016 11:57:54 GMT -5
westom & @keithl, the APC unit I have is NOT a "power strip" but a power regulator (in that it conditions the input voltage which can be higher/lower/at different frequencies to 120v at 50 Hz or ideal power). Even if most electronics can take a variation in input voltage, It can't be a bad thing to feed them a constant voltage. Yes, I get it, surges always take the shortest path to ground. I'm hedging the bet that path won't be through my gear. When I'm home during storms, I always unplug the APC from the wall - thereby disconnecting all my electronic gear. I'm fine with this pragmatic approach, short of installing a lightening rod on the roof. But even that isn't enough as spikes can travel through ground laterally. So maybe move into a Faraday Cage? This is the unit I have: www.audioholics.com/power-conditioner-reviews/apc-h15.
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Post by KeithL on Sept 6, 2016 13:23:13 GMT -5
Yes, that's wrong. (excuse the terms that make it sound like electricity is a living thing) (also excuse the fact that the reality is actually reversed.... electrons usually flow UP in a strike... but "positive charges" flow down....) (in fact, while the spirit of this explanation is actually technically quite accurate, it is downright lyrical) Somewhere in a cloud a whole bunch of electrical charges build up..... And electrical charges "look for" a path to ground. As the charges accumulate, the equivalent of pressure builds up and, eventually, they "jump" to ground. A big group of moving charges is what we call current (and, when it happens all at once, a spark). So, what happens is that the charges jump to ground - and electrical wires (the power grid) are a convenient way to get there. So, the lightning strikes the power lines. And, in order to get to ground from there, it needs to find a path to ground..... The power company has provided various paths to ground for when this happens.... However, because a lightning strike is so big, the charges can't drain fast enough.... so they build up. That's called "voltage drop due to current flow". (Think of water in a flash flood.) This causes what we normally think of as a "surge" on the power line...... The voltage on the line suddenly jumps up because of the "pressure" built up by all those charges that can't drain away fast enough.... And so it tries to find its way to ground through your equipment. (And, since the voltage goes up way above what's normally on the line, and your equipment isn't built to accept that voltage, damage occurs.) The way MOST surge suppressors work is by providing a path to ground for that current to "drain off" through. They do this by, when the voltage on the line goes above some high value, trying to short the excess current to ground. The current takes the path of least resistance - through the surge suppressor. (By shorting, or "shunting" the current, they can "pull" the voltage back down.) This is the way the MOV based ones in power strips work. There are also power strips with circuit breakers. However, circuit breakers are quite slow.... They will open the circuit to keep a shorted appliance from burning your house down... But they are FAR too slow to protect anything from a surge. HOWEVER, it's not at all true that you can't block power surges...... As with the joke with the two guys being chased by the lion..... ("I don't have to run faster than the lion; I just have to run faster than YOU" ) You don't HAVE to block the surge from getting to ground.... All you have to do is to block it ENOUGH that it's easier for it to go to ground some other way (like through your neighbor's appliances, or the surge arrestors installed on the power lines themselves). Lightning is able to jump miles because it has millions or even billions of volts of "pressure" behind it... BUT, a typical power line surge is only a few hundred volts, or, at most, a few thousand volts.... because it has lots of paths to ground (the surge arrestors on the grid, plus every appliance, in every house, near you). (Which is why series surge suppressors have no trouble at all blocking it....... ) In technical terms, a lightning strike acts very much like a current source, which supplies a huge amount of current, for a short amount of time. What you experience as "a power surge" is the voltage drop in the power grid caused by that current flowing to ground through it. Destructive transients can be hundreds of thousand of joules. If on a power cord, a Furman, et al must either 'block' or 'absorb' that energy. Where is this magic part that will 'block' what three miles of sky cannot? Does not exist. How many joules does that Furman (or APC) claim to 'absorb'? Hundreds? A thousand? What happens to hundreds of thousands of joules. I'm a total layman here. I always assumed the surge protectors worked by opening the circuit; like flipping a switch open, or unplugging a wire from the wall plug, I just imagined there was some fancy circuitry in there that had the same effect. So it doesn't absorb the energy, it simply removes the appliance from the circuit. Is that wrong? And are you suggesting that a properly grounded house is sufficient?
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hemster
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Post by hemster on Sept 6, 2016 13:43:09 GMT -5
If I understand you correctly, all of these surge suppression devices are not necessary because our appliances already are sufficient. You mention "proven protection costs about $1 per protected appliance." What is that? westom, Yes, I'd like to know the answer too. Do you mean MOVs?
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KeithL
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Post by KeithL on Sept 6, 2016 13:43:54 GMT -5
There seems to be a lot of confusion between "a lightning strike" and "a power surge". A lightning strike is when lightning actually tries to find a path to ground directly through your home and equipment. While it's true that not much except a lightning rod or something similar will protect your home from a direct hit, because the only option is to direct most of that energy safely to ground, direct strikes are very rare. But that's NOT what most "power surges" are... The VAST majority of "power surges" are caused by lightning strikes on wires or transformers on the power grid - often miles away. The current spike from the lightning strike is grounded through the electrical distribution gird.... and its built-in heavy-duty surge arrestors. And the resulting voltage surge - of a few hundred or a few thousand volts, for a small fraction of a second, is "delivered" to your home over your AC power lines. Electrical equipment isn't designed to operate from those voltages - so it's damaged. In order to protect your equipment, all a surge suppressor has to do is to short enough current to ground to reduce this voltage to a safe level. Since the surge is quite brief, it doesn't even have to do this for very long. Unfortunately, while only a tiny portion of the energy of the original strike is contained in the surge by the time it reaches you, there's still a lot of energy involved. MOVs are somewhat effective in this role because they are small, very cheap, and are actually capable of shunting enormous amounts of energy through themselves (but not too many times). A series surge suppressor simply blocks the few thousand volts that reaches your circuit.... which is actually relatively easy to do. (Just like a cheap plastic water faucet can "block" the billions of gallons of water in your city reservoir.) The reason series suppressors are expensive is that the inductors they use (capable of blocking a few thousand volts, and of passing 15 or 20 amps), are somewhat heavy and expensive to make. (However, unlike MOVs, they don't "wear out".) westom & @keithl, the APC unit I have is NOT a "power strip" but a power regulator (in that it conditions the input voltage which can be higher/lower/at different frequencies to 120v at 50 Hz or ideal power). Even if most electronics can take a variation in input voltage, It can't be a bad thing to feed them a constant voltage. Yes, I get it, surges always take the shortest path to ground. I'm hedging the bet that path won't be through my gear. When I'm home during storms, I always unplug the APC from the wall - thereby disconnecting all my electronic gear. I'm fine with this pragmatic approach, short of installing a lightening rod on the roof. But even that isn't enough as spikes can travel through ground laterally. So maybe move into a Faraday Cage? FYI, this is the unit I have: www.audioholics.com/power-conditioner-reviews/apc-h15.
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Post by KeithL on Sept 6, 2016 13:59:02 GMT -5
The surges that damage equipment almost always come in through wires....... Often power wires - which is why unplugging things often helps. However, you can also get surges through other cables as well. For example, a power surge COULD come in through your satellite TV box, go through the HDMI connection from it to your pre/pro, and then through the HDMi cable to your TV. (If it did so it could destroy the video circuitry in all three.) This is why it's VERY important that cable boxes and satellite TV boxes be properly grounded. (they all include some sort of internal surge suppression.... but it invariably relies on a proper earth ground to function correctly). westom & @keithl, the APC unit I have is NOT a "power strip" but a power regulator (in that it conditions the input voltage which can be higher/lower/at different frequencies to 120v at 50 Hz or ideal power). Even if most electronics can take a variation in input voltage, It can't be a bad thing to feed them a constant voltage. Yes, I get it, surges always take the shortest path to ground. I'm hedging the bet that path won't be through my gear. When I'm home during storms, I always unplug the APC from the wall - thereby disconnecting all my electronic gear. I'm fine with this pragmatic approach, short of installing a lightening rod on the roof. But even that isn't enough as spikes can travel through ground laterally. So maybe move into a Faraday Cage? This is the unit I have: www.audioholics.com/power-conditioner-reviews/apc-h15.
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