DIY surge protection...

Existential Angst wrote:


Hmmm, So you think coil driven mechanical relay is as fast as spikes or surge? Forget it. But there is such a thing call S.S. relay. and it is not a voltage regulator it is a limiter.
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Existential Angst wrote:

The standard protectors are tested against is the so-called 8/20 surge, the 8 means an 8 MICROSECOND rise time. So, the current rises to it's peak value in 8 us, then decays in 20 us after that. Relays take many milliseconds to react, and a lightning surge will just jump right over the open contacts, anyway. So, totally FORGET anything using relays.
Jon
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wrote:

Either you buy a protector that will somehow absorb all that energy. Or you buy protectors based upon how it was done even 100 years ago. Protection is always about where energy dissipated. Either that energy remains outside the building. Or that energy is inside hunting for earth ground destructively via appliances. Adjacent protectors simply give surges even more potentially destructive paths through adjacent appliances.
An effective surge protector means even the protector remains functional. A minimal 'whole house' protector starts at 50,000 amps. Direct lightning strikes are typically 20,000 amps. Yes, the protector must be sized to even earth direct lightning strikes and remain functional. And that means the connection to earth must be additional requirements - short ('less than 10 feet) to earth, no sharp wire bends, no splices. all protectors meet at (again 'less than 10 feet to') the single point earth ground, ground wires separated from other non-ground wires, not inside metallic conduit, etc.
Protection is always about where energy dissipates. If those hundreds of thousands of joules dissipate in earth, then no damage. This is how it was done even 100 years ago.
But somehow a magic box next to the appliance will absorb all those joules? Always view the tech specs. Plug-in protectors rates at hundreds of joules will somehow make hundreds of thousands just disappear? That is what they claim. In analysis, we even traced surges earthed destructive through a network of powered off computers because the surge was permitted inside the building. And because a surge on the black (hot) wire was connected directly to the motherboard by the protector. The protector bypassed protection inside the computer's power supply.
Telcos do not waste money on protectors adjacent to electronics. That switching center must never suffer damage. A switching center, connected to overhead wires all over town, may suffer 100 surges with each thunderstorm - and no damage. Why? Each protector connects short to the single point earth ground. And the protector is up to 50 meters separated from electronics. That separation increases protection.
No protector is protection. None. The only effective protectors make that short connection to single point earth ground. Ineffective protectors (a $3 power strip with some ten cent protector parts selling for $25 or $150) are profit centers. The NIST (US government research agency) discusses those ineffective protectors by describing what every protector must do:

The NIST describes plug-in protectors as "useless". Obviously. It does not even claim protection in its numeric specs. Find those spec numbers that list each type of surge and protection from that surge? No plug-in protector makes protection claims. They are a profit center.
Protection is always about where energy dissipates. IOW why facilities with effective protection both meet and exceed post 1990 National Electrical code. Where does energy dissipate? A protector is only as effective as its earth ground - which no plug-in protector has and therefore will not discuss. Effective 'whole house' protectors come from General Electric, Keison, Intermatic, Siemens, Square D, and Leviton. An effective Cutler-Hammer solution sells in Lowes and Home Depot for less than $50.
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How bout a surge from downed power lines? Ours got knocked down from ice on trees falling on the main lines into the house 4am Christmas eve. Started a fire (12" flames) on the Belkin UL approved spike/ surge protector right next to the christmas tree & plasma TV! Could never get an answer as to why this happened. Knocked out a couple other surge strips including a plug in CO2 detector. Thank god thats all that happened.
http://users.cin.net/~milgil/Belkin_burned1.JPG
http://users.cin.net/~milgil/Belkin_burned2.JPG
http://users.cin.net/~milgil/Belkin_burned3.JPG
http://users.cin.net/~milgil/Belkin_burned4.JPG
http://users.cin.net/~milgil/Belkin_burned5.JPG
Must be something to do with the end of the power- where it dissipates ?
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cncmillgil wrote:

Looks like a pretty good case for metal enclosed surge protectors.
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A friend suffered a 33,000 volt fault to the local distribution. As a result, hundreds of electric meters were blown from their pans. At least 100 clear plastic meter covers in pieces 10 meters from the pan.
Many neighbors suffered damaged electronics and protectors similar to yours. Fortunately, no fires. At least one neighbor had a destroyed 20 amp circuit breaker.
But my friend knows someone who knows this stuff. He only had a 'whole house' protector installed. Therefore he had no damage other than an exploded meter. Even the 'whole house' protector remained functional.
Just another reason why informed consumers earth one 'whole house' protector and do not made money on plug-in protectors. That Belkin does not even claim protection in its numeric specs.
BTW, electric company was not responsible for any damage (as expected). Many electric customers had their meter pans completely replaced due to the explosive power in that 33,000 volt fault.
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westom wrote:

I have not noticed that w is a reliable source of what happens. Perhaps you could provide a newspaper article?
MOVs are the basic protection components for virtually all power circuit surge suppressors. A MOV that can easily handle a 33,000V surge for 100 microseconds is rapidly burned out by a crossed power line ("temporary overvoltage", not a "surge"). Suggesting that a service panel suppressor will provide protection is idiocy.
Provide a spec from any manufacturer that their suppressor protects from crossed power lines.
--
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Well, we all knew this was coming. Mention surge protector, and like a bolt of lightning from the sky, here comes WTom.

So far, I would mostly agree. Except the part about a direct lightning strike. A direct lightning strike is mostly a red herring, because even if the lightning bolt hit the service cable near the building, it's highly unlikely that the path of all or even most of the lightning is going to be through the service wire and into the surge protector. Far more likely, it will arc with most of the energy finding ground outside the building before it ever gets to the surge protector at the panel or meter.

Here;s where Tom likes to start arguing against strawmans and the rant about plug-in surge protectors begins. The actual question was about a whole house surge protector.

Total nonsense. Every line card on a telco switch has surge protection right on the card where it connects to the incoming line. Much like if you take apart an analog modem, you will almost always find MOVs or similar components there.

In fact, just like the IEEE recommends, the telco uses a tiered approach. Yes, they have surge protection where the line enters the building. But they also have it on the line cards. Months ago I even found you semiconductors designed and marketed for telcos that go on the linecards, complete with the application notes. Yet, here we go again.

Please provide us a link to NIST or any other credible source that says plug-in protectors are ineffective as part of a protection plan. You've been asked that here for years and we have yet to see the link.

And here comes the list again. What Tom won't tell you is that of those companies on his list of real effective and responsible manufacturers, most of them also sell plug-in surge protectors. They recommend using them as part of a tiered strategy.
As for the HD solution for less than $50, that doesn't square with your criteria of needing a minimum of 50,000 amps, because they have no such product available at HD.
The best advice was already provided. That was the link to the IEEE guide on surge protection.
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
Everyone can read what respected peer-reviewed engineers recommend. And I can tell you this. They don't say plug-ins are ineffective. Read chapters 5 and 6. Instead, they show them being used as part of a tiered strategy. You put whole house protection at the meter or panel. Then you use plug-ins that route all power and signal through them, to further protect key equipment, eg, TVs, PCs, etc.
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snipped-for-privacy@optonline.net wrote:

I posted links to photos of telco cards with rows of MOVs, yet he claims they don't exist. He is just a brain dead troll like Cliff, and The_Mangled_Toad.
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wrote:

That is not what I said. I said those are not MOVs. MOVs have excessive capacitance. Telcos use a different device that does not have that excessive capacitance. Please read what was posted. You got caught lying elsewhere. So everything from you is only an attack.
Any protection that might work adjacent to electronics is already inside electronics.
Informed consumers dissipate energy so that surges are not even inside the building.
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On Mar 21, 8:47am, snipped-for-privacy@optonline.net wrote:

Tom does not know anything about surge protection so he is trying to bluff his way through. he thinks he is appearing intelligent but most readers can see through his misinformation. It is too bad that he feels the need to rant about things he knows absolutely nothing about. Perhaps he could make a more informed opinion on the type of beer he is drinking.
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westom wrote:

Lightning strikes can be far larger than 50,000A (but low percentage). But a strike to a power line has multiple paths to earth. Investigations have shown the largest lightning-caused surge with any reasonable probability of occurring is 10,000A on an incoming power wire. The 50,000A suppressor rating can handle that. High ratings give long life.
The best information on surges and surge protection is in a guide from the IEEE at: <http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf (also posted by Howard and trader) and a simpler guide from the NIST at: <http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
Neither service panel or plug-in suppressors can reliably handle crossed power lines. MOVs which can handle 10,000A for maybe 100 microseconds are rapidly burned out by longer duration events. (These events are probably the major cause of catastrophic MOV failures.)
I would not make my own suppressor attached to power lines (other than fuse protected MOVs in equipment).

Poor w has to warp a thread about service panel suppressors to his favorite topic - plug-in suppressors. Trying to not repeat traders nice reply....
Franois Martzloff was the surge guru at the NIST and wrote the NIST guide. He also wrote numerous published technical papers. One paper looked at the energy absorbed in a MOV on a branch circuit. It was surprisingly small - 35 Joules max. In 13 of 15 cases it was 1 Joule or less. That was with up to 10,000A coming in on the service wire. There are a couple of reasons for that - I could elaborate if anyone is interested.
Plug-in suppressors are only a "magic box" to w because he refuses to understand how they work - clearly explained in the IEEE guide starting pdf page 40. They work by CLAMPING (limiting) the voltage on all wires (signal and power) to the common ground at the suppressor. Plug-in suppressors do not work primarily by earthing (or absorbing). The guide explains earthing occurs elsewhere.
According to NIST guide, US insurance information indicates equipment most frequently damaged by lightning is computers with a modem connection TVs, VCRs and similar equipment (presumably with cable TV connections). It is likely that much of equipment damage is from high voltages between power and signal wires. This is illustrated in the IEEE guide example starting pdf page 40.
A service panel suppressor can not limit the voltage between power and signal wires. To do that, there has to be a *short* ground wire from the telephone entrance protector to the earthing system near the power service. Also for the cable entrance ground block (and dish....) With a large surge current to earth, the "ground" at the building can rise thousands of volts above "absolute ground". Much of the protection is that power and phone and cable wires rise together. If short ground wires can not be used (as in the IEEE guide example) the guide says "the only effective way of protecting the equipment is to use a multiport [plug-in] protector."
For similar reasons, all protected equipment that is interconnected needs to be connected to the same plug-in suppressor. External connections, like phone, also need to go through the suppressor. Connecting all wiring through the suppressor prevents damaging voltages between power and signal wires.

What does the NIST guide really say about plug-in suppressors? They are "the easiest solution". And "one effective solution is to have the consumer install" a multiport plug-in suppressor.

The required statement of religious belief in earthing. Why aren't airplanes crashing daily when they get hit by lightning (or do they drag an earthing chain)?
Often asked and never answered - 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? - 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 do your favorite manufacturers make plug-in suppressors? - Why does favorite manufacturer SquareD say (for their service panel suppressor) "electronic equipment may need additional protection by installing plug-in [suppressors] at the point of use"?
And why can't you find a source that agrees with you that plug-in suppressors are not effective?
For real science read the IEEE and NIST guides . Both say plug-in suppressors are effective.
--
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My wife is a big fan of the "Holmes on Homes" show (which is actually pretty good). They go around fixing messes previous contractors have made of house construction/renovation jobs. They regularly install whole house surge arrestors on the breaker panels when they re-wire a place.
We've been thinking of getting one installed, so I did a little research. Leviton seems to be the biggest vendor in the US. They have an interesting dodge, which is a surge arrestor that goes in series with electric meter, inside the metter housing. In my case, this is outside of the house, which means if it turns into a fireball, it probably won't do a lot of damage. I also like the idea of stopping the surge as early in the wiring as possible.
http://www.levitonproducts.com/catalog/model_50240-MSA.htm
I've got a query in to see if it will fit in just any old meter housing, and how it compares with some of their breaker panel add-ons. Other than having to deal with the electric company to replace the seal on the meter housing, this thing looks like a snap (literally) to install. The cost of the suppressor is about the same for either approach, but the electrician should be able to install the meter version in considerably less than half the time.
Doug White
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That Belkin did what plug-in protectors do too often. Threaten human life. Any protector that fails during a surge was ineffective - grossly undersized for that surge. The Leviton and 'whole house' protectors from so many other companies much earth a direct lightning strike - and remain functional.
A direct lightning strike is typically 20,000 amps. Therefore the minimally sized 'whole house' protector is 50,000 amps. 50,000 amps without failure.
The most rare of surges is 100,000 amps. An IEEE paper demonstrates what happens when that 100,000 lightning strike hits the utility power wire. Maybe 40,000 amps attempts to enter the home. (the IEEE picture assumes the 'primary' surge protection system is also properly installed).
Only more responsible companies sell 'whole house' protectors. Not in the list are APC, Tripplite, Belkin, and Monster. Companies that sell protectors for real world protection include Leviton, Square D, General Electric, Intermatic, Keison, and Siemens. An effective Cutler-Hammer solution sells in Lowes and Home Depot for less than $50.
And again, no protector is protection - despite what others have posted. Protection is always about where energy dissipates. Always. Either the protector makes an always required short (ie 'less than 10 foot') connection to earth ground. Or that surge will hunt for earth ground destructively via appliances.
Bud has kindly provided the IEEE citation that shows same. See: http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf On page 42 Figure 8 - the surge energy was permitted inside a building. Since he was only using plug-in protectors, then the surge found earth ground 8,000 volts destructively via the adjacent TV. That is what protectors do. Earth a surge harmlessly outside the building or destructively inside. Page 42 Figure 8 is only what that Belkin can do.
All appliances already contain any protection that will work adjacent to the appliance. Your concern is the rare surge that will overwhelm internal appliance protection (ie my friend's 33,000 volt wire dropping on local distribution). Any potentially destructive surge earthed without entering a building will not go hunting 8000 volts destructively via appliances - page 42 figure 8.
The only thing that makes a protector effective is its earth ground. Therefore any money wasted on plug-in protectors is better spent upgrading earth ground. Protection is always about where energy dissipates - which is why earthing must meet and exceed post 1990 National Electrical code. Which is why informed homeowners upgrade what dissipates energy harmlessly outside the building.
This is true of every protector. Why a 'whole house' protector is so effective and why that Belkin does not even claim effective protection in its specs. This: No earth ground means no effective protection. A protector is only as effective as its earth ground. Protection is always about where that energy dissipates earth ground.
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westom wrote:

The only Belkin that failed in this thread was from crossed power lines. It was not a surge, and neither service panel or plug-in suppressors are designed to protect from the much longer duration events caused by crossed power lines.

Service panel suppressors are a real good idea. But from the NIST 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."
Service panel suppressors do not prevent high voltages from developing between power and signal wires. To limit the voltage you need a *short* wire connecting the cable/phone entrance protectors to the ground at the power service.
(And as someone pointed out, a near lightning strike can then induce voltages with interior house wiring acting as an antenna.)
Much of the equipment damaged has power plus phone/cable connections, and is likely damaged by high voltage between power and signal wires.

Martzloff (NIST surge expert) has a paper (probably what w refers to) that has a 100,000A lightning strike to a utility pole behind a house with typical urban overhead distribution. The calculated average probability of a worse event is once in 8,000 years. There are multiple paths to earth so 'only' 40,000A is directed to the house on the service neutral. Service neutrals in the US are connected to ground at the service panel and connected to the earthing electrode(s) dissipating that energy. Some of the energy is transferred to the hot wires and the max probable surge current per wire is 10,000A (also in the IEEE guide pdf page 27).
Incidentally, at about 6,000V from hot bus to enclosure (ground) there is arc-over. After the arc is established the voltage is hundreds of volts. If there is no service panel suppressor this is what dissipates most of the energy on the hot wires. It is one of the reasons so little energy is dissipated in MOVs in plug-in suppressors.

Repeating traders response to w's repeated drivel - the "real world protection" all these manufacturers (except SquareD) sell includes plug-in suppressors. And the $50 devices do not meet w's minimum specs.
For its best service panel suppressor SquareD says "electronic equipment may need additional protection by installing plug-in [suppressors] at the point of use", and the connected equipment warranty is double when "used in conjunction with ... a point of use surge protective device."

If poor w could only read and think he could discover what the IEEE guide says in this example:
- A plug-in suppressor protects the TV connected to it. - "To protect TV2, a second multiport protector located at TV2 is required." - In the example a surge comes in on a cable service with the ground wire from cable entry ground block to the ground at the power service that is far too long (as in my last post). In that case the IEEE guide says "the only effective way of protecting the equipment is to use a multiport [plug-in] protector." - w's favored power service suppressor would provide absolutely NO protection.
It is simply a lie that the plug-in suppressor in the IEEE example damages the second TV.
Lacking any source that supports his drivel w tries to twist an example in the IEEE guide that shows how plug-in suppressors provide protection.

Neither plug-in or service panel suppressors will reliably protect from crossed power lines. This is idiocy.
Provide a spec from any manufacturer that claims such protection.

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." That is - short ground wires from the telephone and cable entry protectors (and dish...) to the ground at the power service.

Complete nonsense.

w's religious mantras protects him from disturbing thoughts (aka reality). Still not explained - why aren't airplanes crashing daily when they get hit by lightning (or do they drag an earthing chain)?
Everyone is in favor of earthing. The IEEE guide explains, for anyone who can think, that plug-in suppressors do not work primarily by earthing and that earthing occurs elsewhere.
For real science read the IEEE and NIST guides - links provided . Both say plug-in suppressors are effective.
There are 98,615,938 other web sites, including 13,843,032 by lunatics, and w can't find another lunatic that says plug-in suppressors are NOT effective. All you have are w's opinions based on his religious belief in earthing.
Still never answered - 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, pdf 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 do your favorite manufacturers make plug-in suppressors? - Why does favorite manufacturer SquareD say (for their service panel suppressor) "electronic equipment may need additional protection by installing plug-in [suppressors] at the point of use"?
--
bud--

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Doug White wrote:

You would, in all probability, have to have permission from the utility to use it.
The clamp voltage is 800V. According to Martzloff (was the NIST surge expert) equipment can withstand about 600-800V surges. The 800V rating sounds way too high to me. (On the other hand, the 330V rating on most suppressors may be lower than needed.) It is a "nominal" clamp voltage. With a strong surge the voltage is forced upward from 800V.
If there is a strong surge, the path to earth is through the neutral from meter can to service panel, through the required neutral-ground bond (almost always in the service panel), and to the earthing electrode. The voltage drop on the neutral will add to the clamp voltage. A surge is a very short duration event, so the current components are relatively high frequency, so the inductance of the wire is more important than the resistance. See the discussion on lead length in the IEEE guide starting pdf page 22. In effect you are adding the neutral wire to the lead length.
I would rather have a suppressor where I have total control over it (service panel).
Probability of catastrophic failure is very low. Martzloff has written "in fact, the major cause of [suppressor] failures is a temporary overvoltage, rather than an unusually large surge." A cause of "Temporary overvoltage" would be crossed power wires, as elsewhere in this thread.
--
bud--

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Another factor, many of the surge protectors intended for panel use have indicator lights that show the status. Some even have audible alarms to indicate that the protection has taken a hit and is no longer functioning. If it's buried in the meter housing, you have no way of knowing if it is still functioning.
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snipped-for-privacy@optonline.net wrote in wrote:

The unit has two LEDs to indicate the condition of the device. I am goign to call Leviton support tomorrow to try to get more info. They don't have teh mnaul/instructions on-line.
Doug White
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Those lights only report a failure that must not happen if the protector is properly sized. Normal failure mode for any protector means it only degrades. Those lights do not report that normal failure mode.
For most any location, a 50,000 amp protector will last at least ten years - in most cases many decades longer. If your neighborhood has a high number of failures, then a 100,000 amp protector will exponentially increase that protector life expectancy. And will significantly decrease its clamping voltages.
Of course, a most critical part is the only part that actually provides protection. That is the earth ground. Every protection layer is defined by the only 'system' component that provides protection. Earth ground. How to make that 'whole house' protector more effective? Upgrade the earthing. Every protector is only as effective as its earth ground. Single point earthing with a connection as short as possible, no sharp wire bends, ground wire separated from other non-grounding wires, wire not inside metallic conduit, etc. All essential to permit a protector to earth direct lightning strikes without damage even to the protector.
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More convoluded logic. If the indicator lights are useless, then why are they included on many of the surge protectors provided by the company Wtom recommends?

We're still waiting for a link to where you can buy one of those 50KA ones at HD for $50 like you claimed.
If your neighborhood has a

Then explain this. You have claimed many times that all appliances and electronics have built-in surge protection. How can that be, since they have no direct short connection to earth ground, which you claim renders protection impossible? Do they come with a mythical earth ground inside? And how can the same type of device that is used in common electronics for surge protection, ie MOV, work inside the home electronics, but according to you, be totally ineffective if used outside the electronics in the form of plug-in surge protector? Not only do they also use MOVs, but those in $20 plug-in surge protectors have significantly LARGER capacity MOVs than the ones inside the $500 home entertainment electronics. How are airplanes protected from surges without an earth ground?
The contradictions here are enough to make your head explode.

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