Whole House Surge Suppression

Discussion in 'Electrical Forum discussion & Blog' started by jadnashua, Jun 28, 2012.

  1. DonL

    DonL Out of the Trades

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    Can I get into the pissing match ? A electric fence hurts and will shut you off in a second.

    The best Whole House Surge Suppression is to get off of the grid.


    Have a good 4th of July. Drink and don't drive.
  2. BobL43

    BobL43 DIY Senior Member

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    And to that, I say Salud!
  3. DonL

    DonL Out of the Trades

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    So You can have Current without any voltage from the source ?

    Seems like that would be Zero power and should not hurt anything.

    What am I missing ?

    Lightning and surge protection are two different things.
  4. DonL

    DonL Out of the Trades

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    I don't think that many brands are any better than others when the manufacture may be the same in many cases.

    I do not use a single point grounding system here because it can cause more problems than it solves.
    I like my lightning to be redirected and not go to my incoming power source. NEC is not always correct when it comes to reality.

    Whole house may be nice but I use a surge suppressor on all of my devices individually.

    The most I am out is a $20 dollar power strip or plug in surge protector, even if I take a direct lightning hit.

    A direct hit may take out my gas discharge tubes in my lightning protectors but may save me and the house.

    Gods power has more power over anything that you can install to protect from her.
    Last edited: Jul 4, 2012
  5. westom

    westom New Member

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    A failed $20 protector means it did no protection. An appliance protected itself while the protector disconnected as fast as possible from the surge. Left the surge connected to the appliance. If disconnecting too slow, then a grossly undersized protector may create a house fire. Have your attention?

    Called a protector means it does something useful? Not without numbers. Defined repeatedly was what does protection:
    " low impedance (ie 'less than 10 feet') to single point ground. "

    Where does energy dissipate? Only the informed can answer that question.

    Knowledge from the NEC only defines simple concepts for "human safety". Electrical concepts for "transistor safety" are different. NEC addresses concepts such as wire thickness and resistance. Surge protection involves wire length and impedance. A low resistance wire can also have excessive impedance.

    Of course, that was posted previously and repeatedly.

    Return to what everyone was taught in elementary school science. How a lightning rod works. Lightning (the typical surge) seeks earth ground. Finds a conductive and destructive path to earth via a church steeple. Yes, wood is electrically conductive. Now, numbers not taught then. Wood is not very conductive. So 20,000 amps creates a high voltage. From high school science: 20,000 amps times a high voltage is high energy. Church steeple destroyed.

    Back to elementary school science: Franklin earthed lightning rods. Do lightning rods do protection? Of course not. A lightning rod is useless without its 'short as possible' connection to a best earth ground. To what harmlessly absorbs energy. Now 20,000 amps creates a near zero voltage. 20,000 amps times a near zero voltage is near zero energy. No church steeple damage.

    A lightning rod works when a surge connects harmlessly to earth. A ''whole house' protector does same. DonL's protectors are like the wooden church steeple. A poor connection to earth (creates a high voltage). Informed homeowners install a 'whole house' protector with a conductive (ie 'less than 10 foot') connection to earth. Then have near zero voltage. No damage even to the protector (or to gas discharge tubes). A low impedance (conductive) connection to earth means even protectors do not fail.

    Grossly undersized protectors fail on surges too tiny to overwhelm superior protection inside appliances. This gets the naïve to recommend them. Sometimes a protector does not disconnect fast enough. Then a house fire can result. Another problem when a surge is permitted inside the building.

    Those, who learned science, were hired to undo a mess created by naive radio station personal. The naive foolishly thought grounds were causing problems. Probably due to NEC knowledge rather than how electricity works. A case study explains a solution by fixing the compromised earthing system. At no time did they waste money on protectors adjacent to electronics:
    http://www.copper.org/applications/electrical/pq/casestudy/nebraska.html

    Bottom line - a protector is a connection to earth or it is "useless". A point made constantly because so many will have difficulty unlearning myths and propaganda promoted by advertising and hearsay.

    Step one: did the advertising provide any numbers? If not, it was probably a lie. Step two: did advertising discuss where energy dissipates? If not, again a sales myth. No low impedance connection to earth means no effective protection. A protector is only as effective as its earth ground.
  6. BobL43

    BobL43 DIY Senior Member

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    wwhere are you westom? your location shows nja; is that India?
  7. jwelectric

    jwelectric Electrical Contractor/Instructor

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    He is misquoting some of the publications of Martin Conroy of Computer Power and Consulting Corporation, Omaha, Nebraska.

    Everything he is talking about has to do with the prevention of lightning damage to transmitting towers such as for radio and TV. Some of what he is saying is true for these installations but his theory of current flow has many flaws. He is also mistaken about built-in surge protection in our appliances.

    In his last post he made an attempt at destroying anything published in the NEC yet addresses surge protection that would be under the rules of the NEC. I suppose he hasn’t done any research on the authors of the NEC or he would know that most of them can decorate their wall just as well as Mr. Conroy and some even better.

    Based solely on the content of his post in this thread it is obvious that he is self-taught over the internet and is totally confused on the subject matter.
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    FWIW, most devices I've looked at have rudimentary, if any, surge suppression built into them. Some things have a noise filter, but that's not the same thing. Most apply the power directly to either a transformer or a rectifier. Yes, there will be some filtering required on most things electronic, as the ripple from a ps otherwise would be too large to allow it to either function or if it did, function very well. Very few devices I've looked at (and I admit I'm not a specialist in this area) have any incoming voltage clamping (usually MOV's) or other devices (spark gaps) to contain any out of tolerance inputs. Their output of internal ps may be quite robust, but that assumes the input power is within range.
  9. DonL

    DonL Out of the Trades

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    A metal-oxide varistor is Great

    I use the MOV type that just shorts out when they reach a certain voltage, then the fuse or breaker opens.

    Never seen one smoke, but the MOV will stay shorted if it gets a big surge, and most good protectors have a led if the MOV has any leakage, or the device is not working.

    The MOVs work good, but you have to have a fuse to open the circuit just in case they short.

    I like to use the lower voltage MOVs because it don't do much good to Clamp at 220V if you are protecting a 120V device, Many clamp at near 200-220 V. They must be made for people that connect a 120V appliance to 240. Even tho the plug don't fit it can happen by incorrect wiring.

    140 Volt MOVs seem to be the best for protection at 120 Volt normal use.

    The good protectors come with a warranty for what you have plugged in , but I have never had the need to see if the warranty really pays out.

    A lot of the filtering is to keep computers and switching supplies from sending RF or Harmonics back into the AC power, and eliminates RF from coming in. X10 devices will not work very well when plugged into a good filtered strip.
    Last edited: Jul 5, 2012
  10. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    120vac RMS has peak voltages considerably higher than 120vac.
  11. jwelectric

    jwelectric Electrical Contractor/Instructor

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    if the RMS value is 120 then it would be 120 times 1.414 = 169.68
    169.68 times .707 = 119.96

    Edited to add;

    The cosine of the angle divided into 1 times the RMS voltage will give you the peak voltage of the sine wave. 1/.707*120=169.68 volts
    Last edited: Jul 6, 2012
  12. BobL43

    BobL43 DIY Senior Member

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    and the peak to peak voltage would be 120 volts times 2 X the sq root of 2 which would make that voltage about 339 volts.
  13. DonL

    DonL Out of the Trades

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    It surprises me that many Surge Protection Power strips are UL listed , but are also claimed to be a fire hazard.
  14. DonL

    DonL Out of the Trades

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    I think many times people do not really know the rating for what they buy. A true RMS meter is nice and I use a o-scope for reading P-P. It is surprising to see what comes down the AC line.

    I have a computer logger for a AC Line monitor, and it works good when I have it online.

    Seems like if you have a lot of Joules then you must be better, people like large numbers, but where does the surge get dissipated ?. The key is to keep the energy from entering your house like Jim did.


    I prefer having bigger Jewels, My Girl does too.
  15. BobL43

    BobL43 DIY Senior Member

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    Those jewels are the only ones that are important. You cannot buy them in a store at any cost, but if you are a bad boy, you may lose them in your sleep. Elena Bobbit removed the tool, but not the jewels, and John was able to make a loving or (living) on the results. Remember that story?
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