Data & Power Line Surge protection

Discussion in 'General Electronics Chat' started by lanker45, Jul 28, 2012.

  1. lanker45

    Thread Starter Member

    May 19, 2009
    23
    1
    Hi All Been awhile since last here.... Just searched and I'll be darned If I can find any thing with respect to Data & power line surge protection....
    Last week received a very nice lighting strike got me both frount and back doors, Had to replace the entire network down to the cable.... Also took out four 4 computers two top end two low end units....Any way wanted to look around and see if any one has built a good surge arrestor for both small & large surges. I picked up an 3 phase industrial unit and there using chokes & MOVs on there version. I also plan/build usage of spark gap units to to the final build... Any Ideas any one? Have googled this to death, APC has rack mount units for the data/pxb Mfg,# PNETR6 & PTELL2R stand alone... Am leaning that way for data/PBX protection....
     
  2. lokeycmos

    Active Member

    Apr 3, 2009
    432
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    if you get a direct strike nothing will protect your equipment
     
  3. lanker45

    Thread Starter Member

    May 19, 2009
    23
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    I have been told that over and over..... However. How are Cell Phone towers Protected when they get hit more often then ones home??????
    So thats kinda were I'am at to at least get that sort of protection...
     
  4. #12

    Expert

    Nov 30, 2010
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    I'm thinking you would need to provide an alternate path for the current. Historically, these are called, "lightning rods". They also require a good, distributed, grounding network, like buried pipes. It amounts to a crude Faraday cage around your building.

    Then there is the aspect of lightning induced current entering on power lines and data lines. Each of these must be protected individually, which seems to be the method you have been exploring.
     
  5. westom

    Member

    Nov 25, 2009
    52
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    Most only buy what advertising, retail salesmen, and hearsay recommend. Then when damage occurs, they *assume* nothing can do protection. Bull - as demonstrated by your damning question. Telephone switching centers (COs), connected to overhead wires all over town, suffer about 100 surges with each storm - and no damage. Or is your town without phones for four days after every thunderstorm?

    Protection from direct lightning strikes was routine even 100 years ago. But first learn a basic fact. No protector does protection. Either a protector connects a surge low impedance (ie 'less than 10 feet') to what does protection. Or is a protector that the NIST calls "useless". A profit center.

    Earth ground does protection as Ben Franklin demonstrated in 1752. A protector (or lightning rod) is only as effective as its earth ground. No earth ground means no protection (as so many learn the hard way with power strips). Two completely different protectors exist. A typically undersized protector that has no earth ground AND is adjacent to an appliance. Or the well proven, superior, and effective protector with numbers that define protection even from direct lightning strikes. That does for appliances what a lightning rod does for the structure.

    A 'whole house' protector is sold by companies with better integrity. Including ABB, Siemens, Intermatic, Polyphaser, General Electric, Square D, Leviton, or Ditek to name but a few. Most are names that any guy would know. A Cutler-Hammer solution sold in Lowes ahd Home Depot for less than $50. That is best protection for about $1 per protected appliance. Even needed to protect power strip protectors.

    But again, a protector is only a connecting device. No protector does protection. No protector will stop what three miles of sky could not - as the most easily decieved would like to believe. Or read its spec numbers. How does that few hundred joules in a power strip or UPS absorb a surge that is hundreds of thousands of joules. It must block or absorb a surge IF adjacent to an appliance. It doesn't - as even its own spec numbers demonstrate.

    Instead, worry about what does the protection - single point earth ground. What any effective protector always connects to. That ground must meet and exceed code requirements. Because hundreds of thousands of joules dissipate harmlessly only in earth. Or destructively inside the building.

    Either a surge finds earth ground innocently via one 'whole house' protector. Or it hunts destructively for earth via appliances. Your choice. The well proven and effective soluton. Or one only recommended by those who never learned this stuff; who are educated by advertising and hearsay. Who assume nothing can avert damage because of that advertising.

    Cable needs no protector. The cable already has a wire that connects low impedance (ie 'less than 10 feet') to earth ground. Some protection systems have no protectors. But every protection system always has a low impedance (ie 'less than 10 foot') connection to earth. Then any surge on cable need not go hunting inside - destructively.

    Telephone wire cannot be earthed directly. So all telcos 'install for free' a 'whole house' protector where their wires meet yours. But again, only as effective as the earth ground that you are responsible for providing and maintaining.

    Incoming wires that have no protection are AC electric. Therefore a direct lightning strike far down the street is a direct strike incoming to every appliance. Either you earth that surge where it enters the building (breaker box or meter). Or your only protection is what already exists inside every appliance. Surges that do damage (typically once every seven years) overwhelm existing appliance protection. And easily blow through the most expensive power strip.

    Existing appliance protection makes most surges irrelevant. Your concern is a rare surge that can overwhelm that superior protection. For over 100 years, every facility that cannot have damage (ie cell phone towers, munitions dump) has always earthed a 'whole house' protector. Always. So that internal appliance protection is not overwhelmed. So that direct lightning strikes do not cause damage.

    But again, a protector is only as effective as its earth ground. Get a 'whole house' protector. But worry more about what actually does all protection - the earthing.
     
    Last edited: Jul 31, 2012
    #12 likes this.
  6. lanker45

    Thread Starter Member

    May 19, 2009
    23
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    #12 & westom... correct, One needs to diffuse the surge to render it harmless, then for those smaller surges a ups works really good. In my case I have them in the IT room/shelf, and on most all other computers, and have about 4 hrs run time....As an IBEW electrician you really don't get into surge arrester types other than proper grounding of electric service, and in my case failed really well.... Every thing is code grounded as I had checked some time ago, but failed to provide a path for the surge. This thing was so bad that I had electric arc marks between the fence post and the latch for all the gates were it was looking for ground. My first step here is to megger all ground rods to earth and decide if in fact there good and if it was just bad connections from ground wire to rod bla bla bla.. Next, comes a ground wire from the IT shield to ground rod, both wires get cadwelded to the rod then comes the surge arrestor part and is were I hope to get plenty of input so that other folks can build there own foolproof surge protection....As westom noted there are whole house protectors but sorry I still don't trust them as most still depend on the electric service ground rods & clamps as in my case were part of the failure.....They, most have no indicators if they are good or bad and one is still in the dark so to speak. I have some cadweld from ebay as you can usually only buy this material by the case from the electric supply house. I plain to build several spark gap tubes for starters unless of course these Funk-Entstordrossel B82505-W-A7 chokes will work in place or in concert with the spark gap units input anyone.
     
  7. bud--

    New Member

    Jun 13, 2012
    15
    3
    Excellent information on surges and surge protection is at:
    http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
    - "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE in 2005 (the IEEE is a major organization of electrical and electronic engineers).
    And also:
    http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges%20happen!.pdf
    - "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology in 2001

    The IEEE surge guide is aimed at people with some technical background.

    The IEEE surge guide explains (starting page 30) how plug-in protectors (and UPSs with the same protection) work. It is not primarily by earthing the surge, earthing occurs elsewhere. Plug in protectors work by limiting the voltage from each wire (power and signal) to the ground at the protector. The voltage between the wires going to the protected equipment is safe for the protected equipment.

    When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like coax also must go through the protector.

    All these "companies with integrity" except SquareD and Polyphaser make plug-in protectors and say they are effective.
    Westom says plug-in protectors don't work.

    Service panel protectors 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 by themselves prevent high voltages from developing between power and phone/cable/... wires. The NIST surge guide suggests that most equipment damage is from high voltage between power and signal wires. (An example of where a service panel protector would provide no protection is the IEEE surge guide example starting page 30.)

    The author of the NIST surge guide looked at the current that would come to a building from a lightning strike. He used a strike of 100,000A to the high voltage primary wire at a utility pole adjacent to a house in typical urban distribution. Only about 5% of lightning strikes are stronger, and this is a very near worst case. The current on each power service wire was 10,000A. Service panel protectors with far higher ratings are readily available. High ratings mean the protector will have a long life. Recommendations for ratings are in the IEEE surge guide page 18.

    Service panel protectors are likely to protect anything connected only to power wires from even a very near very strong lightning strike. They may or may not protect equipment with both power and signal connections.

    Complete nonsense.

    Just the opposite may be necessary.
    SquareD says for their "best" service panel suppressor "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use."

    The author of the NIST surge guide also investigated how much energy might be absorbed in a MOV in a plug-in protector. Branch circuits were 10M and longer, and the surge on incoming power wires was up to 10,000A (the probable maximum, as above). The maximum energy at the MOV was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. Protectors with far higher ratings are readily available.

    One of the reasons the energy is so low is that for a strong surge at about 6,000V there is arc over [US] from the service panel busbars to the enclosure. When the arc is established the voltage is hundreds of volts. Since the enclosure connects to the earthing system that dumps most of the surge energy to earth.

    (Neither plug-in or service panel protectors work by absorbing surges. But they both absorb some energy in the process of protecting.)

    The code just requires a ground block that allows the coax shield to be earthed.

    Needs no protector? The IEEE guide says “there is no requirement to limit the voltage developed between the core and the sheath. .... The only voltage limit is the breakdown of the F connectors, typically ~2–4 kV.” And "there is obviously the possibility of damage to TV tuners and cable modems from the very high voltages that can be developed, especially from nearby lightning."

    In westom's fantasies.

    Both the IEEE and NIST surge guides say plug-in protectors are effective.

    Airplanes regularly get hit by lightning.
    Are they crashing?
    Do they drag an earthing chain?

    Much of this is the same misinformation westom posted a month ago.

    =========================
    Sounds like the OP had a direct lightning strike to the building. Protection from direct strikes requires lightning rods, plus there is other protection added with the rod system. It can certainly be done, but not many places have enough risk of a direct strike to justify rods.

    If you have a surge coming in on utility wires, and there is a 2,000A surge current to earth, and you have a quite good 10 ohms resistance to earth through the power earthing system, the building 'ground' will rise 10,000V above 'absolute' earth potential. A lot of the protection is that all wires - power, phone, cable,... - rise together. That requires that entry protectors, such as cable, have a short ground wire to a common connection point on the power earthing system. An example of a wire that is too long is in the IEEE surge guide starting page 30.

    You want one connection to a single earthing system with a common connection point to connect cable, phone, ... entry protectors. The power service N-G bond connects to the earthing system, as does a service panel protector, if any.

    I would use standard protectors and not kludge together parts. I don't know how a spark gap would be used inside a building (gas discharge tube?). If using point of use protection note that all wires to a set of protected equipment must go through the protector.
     
    #12 likes this.
  8. gerty

    AAC Fanatic!

    Aug 30, 2007
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    When cell towers get hit, they die just like anything else. What makes you think they don't?
     
  9. #12

    Expert

    Nov 30, 2010
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    westom and bud were very educational. Gerty, can you provide more information?
    lanker, can you provide a link to these? Funk-Entstordrossel B82505-W-A7 chokes

    Personally, I have seen the cap of a "surge protector" attached to the 120V lines and the neutral line approching a farm house because that was all that was left of it. I would love to know more about where to buy this kind of product after seeing the $30 size blown up like a firecracker. Anybody got sources?
     
  10. gerty

    AAC Fanatic!

    Aug 30, 2007
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    Last edited: Aug 1, 2012
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  11. westom

    Member

    Nov 25, 2009
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    Electronics atop the Empire State Building are struck 23 times annually without damage. Atop the WTC were 40 strikes annually without damage. Routine are direct lightning strikes without damage. But only if earthing exists as even the NIST and IEEE so strongly require. For example, the NIST says and there is no way around this:
    The NIST then defines protectors (ie adjacent to appliances):
    Virtually all professionals define protection in terms of what does it - the earthing. Another with decades of experience:
    Earthng that meets code may not be low impedance. Protetors that are not connected as short as possible also would not have that always required low impedance connection.

    Some protection systems do not have protectors. But every effective protection system (to protect a building - lightning rod; or to protect appliances- whole house protector) always has the only item that provides that protection - earth ground.

    Previously described was the 'secondary' protection layer. Also inspect the 'primary' protection layer. What defines each protection layer? The earth ground. A picture of what in the 'primary' layer should be inspected:
    http://www.tvtower.com/fpl.html

    Routine is to have direct lighting strikes without damage even to the protector. Essential is what harmlessly dissiaptes that energy and how it is connected - earth ground.
     
  12. gerty

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    Last edited: Aug 2, 2012
  13. bud--

    New Member

    Jun 13, 2012
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    Westom's point is that plug-in protectors, which are not well earthed, can not possibly work.

    Immediately following westom's quote from the NIST surge guide is a list of surge protectors that can be used.
    Number 6 is "Plug-in...The easiest of all for anyone to do. The only question is 'Which to choose?'"

    What else does the NIST surge guide says about plug-in protectors?
    They are "the easiest solution".
    And "one effective solution is to have the consumer install" a multiport plug-in suppressor.

    The IEEE surge guide? It has 2 detailed examples of protection. Both use plug-in protectors (that westom says don't work). That is after a long discussion of them.

    As the IEEE surge guide explains (starting page 30) plug in protectors do not work primarily by earthing surges. Earthing occurs elsewhere. Plug-in protectors work by limiting the voltage from each wire (power and signal) to the ground at the protector. he voltage between the wires going to the protected equipment is safe for the protected equipment.

    Contrary to westom's beliefs, both the IEEE and NIST surge guides say plug-in protectors are effective.

    It all was in a thread a month ago. But westom ignores anything that does not fit his limited beliefs of protection.

    I do agree that cell phone towers, commercial broadcasters, and even ham radio operators can protect from a direct lightning strike to their antennas. Handling the full lightning strike requires far more elaborate techniques that we need for surges mostly coming in on utility wires at our houses.
     
  14. westom

    Member

    Nov 25, 2009
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    A telco switching computer is connected to overhead and underground wires all over town. Therefore it suffers about 100 surges with each storm. How often is your town without phone service for four days while they replace their electronics? Never. Because direct lightning strike without damage is routine. So routine that damage is often considered a human failure.

    Much of what we do today for surge protection was pioneered in munitions dumps. Where direct strikes without damage are routine. Protection is not defined by a protector. Professionals define protection in earthing. For example, the NIST is quite blunt about this:
    Then the NIST describes protectors that do not have earthing:
    BTW, its was not a lightning rod that protects electronics atop the Empire State Building. It is an earth ground that lightning rod connects to. Because even lightning rods are only as effective as their earth ground. No earth ground means no effective protection.
     
    Last edited: Aug 2, 2012
  15. bud--

    New Member

    Jun 13, 2012
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    Broadcast and ham antennas regularly get hit by lightning and equipment survives. Principles of protection are rather well known.


    Westom just keeps repeating the lie that the NIST says plug-in protectors do not work.

    Repeating:
    Immediately following westom's quote from the NIST surge guide is a list of surge protectors that can be used.
    Number 6 is "Plug-in...The easiest of all for anyone to do. The only question is 'Which to choose?'"

    Westom says plug-in protectors do not work.
    Maybe he can answer simple questions:
    - Why do the only 2 actual examples of protection in the IEEE guide use plug-in protectors?
    - Why does the NIST guide says plug-in protectors are "the easiest solution"?
    - Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in protector?
    - Why do westom's "companies with integrity" make plug-in protectors and say they are effective?
    - Why does manufacturer "with integrity" SquareD says "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use"?

    For real science read the IEEE and NIST surge guides. Excellent information on surge protection. And both say plug-in protectors are effective.

    Westom's view is way too simple. Another major element of protection is what is, in effect, a Farady cage formed by the structural steel. The top of the building may be 200,000V above 'ground' during a strike.

    And still not answered - airplanes regularly get hit by lightning.
    Are they crashing?
    Do they drag an earthing chain?
     
  16. lanker45

    Thread Starter Member

    May 19, 2009
    23
    1
    #12 those B82505-w-a7 chokes, look over at Mouser.com, other then that have not found them...A very good read for everyone here is @ megger.com look for "Megger_Getting_Down_To_Earth" pdf That provides all info on proper earthing from the NEC to The IEEEE..... I will be using Fall-Of-Potential to perform my tests, I just need to be savy and produce a signal somehow, I need to reread page 16 on and see if I can Inject a ground signal using this 120-20vac/10amp varic and use copper-clad ground rods 18-24" for test rods???? will post back. No matter what, one MUST have a proper earthed ground system for any surge protection to work correctly.
     
    #12 likes this.
  17. lanker45

    Thread Starter Member

    May 19, 2009
    23
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    Please keep in mind everyone, that we collective can think Outside-the-Box here.... I'am here to protect my family, with respect to lighting strokes, that entered my home, lets put all our knowledge into perspective so we all can benefit from those efforts.
     
  18. lanker45

    Thread Starter Member

    May 19, 2009
    23
    1
    OH, the airplane thing.. LOL .... Airplanes have a complete circuit system, with lighting strokes your missing part of the circuit lol....Now, should you be able to complete that lighting stroke circuit and make it usable, please please please let me know ASAP
     
  19. westom

    Member

    Nov 25, 2009
    52
    5
    Homonyn - an argument without relevance to the discussion. An irrelevant argument to confuse others with something completely different. It only sounds same; to avoid admitting facts. When was the last time your house was flying through thunderstorms?
     
  20. bud--

    New Member

    Jun 13, 2012
    15
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    Entirely relevant.

    If you understand how a plug-in protector works you should have no trouble figuring out how to protect an airplane.

    Admitting facts? Where are the answers to simple questions:
    - Why do the only 2 actual examples of protection in the IEEE guide use plug-in protectors?
    - Why does the NIST guide says plug-in protectors are "the easiest solution"?
    - Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in protector?
    - Why do westom's "companies with integrity" make plug-in protectors and say they are effective?
    - Why does manufacturer "with integrity" SquareD says "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use"?

    -----------------------------------
    Sure (ignoring airplanes), but even with a good earthing system with a strong surge the 'ground' at the house will rise thousands of volts above 'absolute' earth potential.

    The author of the NIST surge guide 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, look at the bonding of phone, cable,... entry protectors to the power earthing system. You need short ground wires to limit the voltage between power and phone/cable/... wires during an 'event'. A large part of protection is that all wires rise together during a strong surge event. (An example of a ground wire that is too long is in the IEEE surge guide starting page 30.)

    IMHO it is not particularly useful to go past 2 ground rods for earthing - the law of diminishing returns takes over. Rods are one of the worst earthing electrodes. One of the best is a metal municipal water system. You can't use a variac for fall of potential since the neutral of the variac is connected to earth. You would also need an isolation transformer.

    Thinking outside the box? You can have thousands of amps (but for very short periods). There are effects, like wire inductance, which we usually ignore for power wiring. Again IMHO it is not a good idea to 'roll-your-own' protection. Commercial devices by well know companies are designed by people who understand how surge protection works. I used to have a homemade plug-in protector but retired it long ago because it did not have adequate protection from failing MOVs.
     
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