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Are PC surge protectors needed in the UK?

Discussion in 'Electronic Repair' started by Lem, Jul 8, 2004.

  1. w_tom

    w_tom Guest

    Transmitted an incomplete post. Sorry for the mistake.
    Now for that airplane. Notice earth ground is the tail
    section:
    http://bm6aak.myweb.hinet.net/file/456.gif

    Of course this airplane ground is completely beyond the
    scope of the current discussion. Airplanes are more difficult
    to ground. A Pan Am 707 was destroyed by lightning over
    Elkland MD because internal grounding was not sufficient. An
    airplane must be grounded so that any part can become an earth
    ground; making airplane design more challenging. We, on the
    other hand, are having enough trouble discussing simple
    structural earthing - a well proven 1930 technology. Why then
    complicate it with airplanes and other irerelevant questions?
     
  2. Ron Reaugh

    Ron Reaugh Guest

    No problem. Here:
    http://sturgeon.apcc.com/techref.nsf/partnum/990-7015/$FILE/7015-1.pdf
    Section 9.4

    Do you understand what common mode means with respect to the above spec and
    do you understand how that differs/same as the general concept of common
    mode and how that relates to these issues?

    In order to protect a device from an undesirable voltage arriving over the
    power cable one simply shunts that unwanted voltage such that it appears
    equally on all the wires on that power cable i.e. AC-hot, AC-neutral and
    the ground wire which connects to the chassis of the device. That shunt is
    done with capacitors and surge diodes or MOV devices etc. or in the old days
    on your phone line with a spark gap. That's basically what a surge
    suppressor does. The device's input components therefore see no intolerable
    VOLTAGES and it survives. It makes no difference to the device if the whole
    device(chassis and all) jumps to a million volts during the episode. Ever
    heard of a Faraday Cage?
    Not relevant. What happens on an airplane? The protection issue isn't
    grounding a surge current; the issue is maintaining important components at
    a stable/safe voltage with respect to one another such that nothing gets
    damaged. Ever heard of a Faraday Cage?
    In large buildings as in hydroelectric plants there is NO SINGLE POINT
    ground but multiple connections to a common ground cage/plane. On an
    airplane there isn't even one point to ground except an ionized air column t
    hat chooses its own path for a few microseconds at a time on occasion.
    Ever heard of the concept of a ground plane? Every heard on the concept of
    capacitive coupling and AC impedance? How does a Faraday Cage relate to a
    ground plane?
    You're walkin into my backyard now. Now what's the difference in design of
    that DA for 8 bit 800MHz conversion and 24 bit 200KHz conversion? DAs are
    more fun that ADs.
    It's entirely relevant to demonstrating that you have no understanding of
    the issues in question.

    The answer is that the principles of how to do system input protection on an
    airplane are IDENTICAL to how to do them at home or in a high rise.

    The NUMBER ONE FAILURE of an incompetent designer in this arena is to
    mistake that a ground connection has much to do with the issue; it does
    NOT. The ground connection has much more to do with other issues like the
    safety of the guy who is using the box and the UL and the national
    electrical code. Why do you suppose that US home wiring didn't even include
    a 3rd wire(ground) until the 50's? Do you think some new physical law was
    suddenly discovered?

    One can protect a gadget from surges WITHOUT a ground wire or any ground at
    all; that's the WHOLE point. Shunt the surge voltage such that it's common
    moded and to the chassis at the input and outputs and the device is
    protected.
     
  3. Ron Reaugh

    Ron Reaugh Guest

    OH, cool but of course it simply proves my points.
    You mean beyond you.
    No, airplanes are impossible to proactively ground while in flight(save a
    high energy beam) and much more importantly the is no need to ground an
    airplane in flight. There is just a need to have a good continuous Faraday
    Cage. Damn, how did anyone ever survive when planes were made of wood or
    paper(or are they non-conductors)?
    Oh, you mean the Faraday Cage was discontinuous or flawed or maybe it was a
    super bolt of the kind that has punched holes in heavy gauge steel petroleum
    tanks.
    In any case I'll bet that the cockpit radio was undamaged at least until
    impact.
    Because device/PC protection design has little to do with earth grounding.
     
  4. Ron Reaugh

    Ron Reaugh Guest

    Wrong. Topologically the UPS is "between".

    WRONG! About a critical 10 nanoseconds WRONG nevermind the impedances and
    common mode condiderations!
    Not in the critical time domain.
    NO, the first component with surge suppression topologically is usually the
    one that takes the HIT. Do you suppose that's by design?

    OH, you mean unless the building is a heavily constructed Faraday cage and
    all wiring has feedthru bypass and surge suppression, then a destructive
    transient could get through and that has NOTHING to do with you high
    transient impedance ground wire.. Why is it that we all knew that?
    HUH, frequently good surge protectors are destroyed by big surges just as
    they are designed to do. The good one FAIL closed circuit where protection
    is even better!
    NO, a large server farm has grid ground and power grid firewalls.
    No, you are getting closer to reality.
    To a good Faraday cage or ground plane. A circuit of LOW AC IMPEDANCE.

    What that all boils down to is design the Faraday Cage or ground plane well
    and has little to do with actual earth grounding save the UL and electrical
    code.
     
  5. Chaos Master

    Chaos Master Guest

    J.J. said:


    Happened here. Power surge, while I was working on a MS-Word document.

    Returned, Windows booted, but crashed at the desktop, so I entered using a Win98
    boot disk and ran Scandisk.

    2 or 3 bad blocks, and some files/Windows' registry were corrupted.

    []s
     
  6. w_tom

    w_tom Guest

    Please feel free to show us an MOV datasheet that says
    That claim is classic urban myth. MOV data sheets define
    normal operation. MOV is at end of life typically when it
    degrades by about 5%. How can it degrade 5% and yet
    vaporize? It cannot. Bottom line remains - a properly sized
    protector shunts the transient and remains fully operational.
    Eventually MOV degrades; does not vaporize. Vaporizing is
    when the MOV grossly exceeds manufacturer specification - is
    grossly undersized for the task. But purveyors of undersized
    and ineffective protectors want consumers to believe their
    overpriced protector should vaporize on every surge. Scam is
    the better word.

    In the meantime, there is no topology in electronic
    circuits. Electrically, a shunt mode protector is not
    "between" the appliance and a surge no matter how much junk
    science topology is rationalized. But then this thread is
    full of myth purveyors promoting such junk science reasoning -
    such as MOVs are designed to protect by vaporizing. Which
    plug-in manufacturer do you work for, Ron Reaugh?
     
  7. w_tom

    w_tom Guest

    Well lets see. The Boeing 707 was an entire 'faraday cage'
    of aluminum. And inside that aluminum 'faraday cage' was a
    completely enclosed fuel tank - another faraday cage. How did
    lightning get through two faraday cages to explode the fuel
    tank on that Boeing 707? And why was the correction to
    install more grounds inside that 'faraday cage'? Could it be
    that no sufficient 'faraday cage' exists? Yep.

    Ron, when you get some real world experience with 'faraday
    cages', then come back and share your experiences. In the
    meantime, grounding inside that 'faraday cage' is essential
    for safe airline operations - so that lightning will pass
    through the inside of that 'faraday cage' without doing
    damage. Lightning caused damage inside that 'faraday cage'
    over Elkton MD.
     
  8. w_tom

    w_tom Guest

    Ron. Did you read your citation before posting it? Where
    is the reference to common mode protection? Where are any
    numbers that apply to common mode protection? Once APC used
    to provide far more numbers when they claimed to protect from
    Normal mode transients. Now they don't even make those
    claims. Numbers provided by Ron's citation:
    Hell. They don't even list dBs for the noise filter. What
    kind of spec is that? Noise filter for what? Incoming AC
    line? Output power line? Clearly these are specs for the
    technically naive.

    After one surge, the entire UPS is toast? Look at those
    pathetic numbers. Only 160 joules? Only 6500 amps?
    Effective protection starts at about 1000 joules and 50,000
    amps. Thank you Ron for demonstrating pathetic protection
    from that plug-in UPS.

    Oh - where do they mention anything about 'faraday cage'
    protection?

    In the meantime, Ron describes normal mode protection:
    Where is the common mode protection? Not in that citation.
    Not in what Ron describes. Just another reason why that
    plug-in UPS does not provide effective protection.
     
  9. w_tom

    w_tom Guest

    View specs for a plug-in protector. It claims to protect
    from a type of surge that does not typically exist. That way,
    the myth purveyors will assume it protects from all types of
    surges. And so we have a common quote - "a surge got past my
    surge protector". In reality, the surge took a left turn to
    get the surge protector and a right turn to attack the
    computer - simultaneously.

    Get a surge protector that protects from a type of surge
    that actually does damage. So which one do you install? The
    one that costs tens of times more money per protected
    appliance, OR the one that costs so much less and even
    protects from the destructive type of surge? The latter is
    the single, properly sized, and properly earthed 'whole house'
    protector. Now that the best protector is also the most cost
    effective, we can compare that price to what we might lose
    without installing it. IOW the 'whole house' protector
    provides a basis to decide protection for everything inside
    the house.

    Is a PC surge protector needed in the UK. No: if protectors
    is the ineffective plug-in type that may even contribute to
    damage of an adjacent computer. Maybe: if it is the less
    expensive and more effective 'whole house' type.
     
  10. w_tom

    w_tom Guest

    Why is 'absorb' verse 'shunt' an important difference? If a
    protector absorbs surges, then it sits between surge and the
    protected device - in series. It must stop or block surges.
    But then it must be a series mode protector. It is not. It
    is shunt mode. Shunt mode protectors don't function if they
    absorb surge energy. Difference between 'shunt' and 'absorb'
    is important to keep the consumer confused.

    A shunt mode protector connects off to the side; is not
    located electrically between protected device and incoming
    transient. A shunt mode protector connects as if it was
    another appliance - albeit much closer to the single point
    ground.

    Absorbing is what the plug-in protector manufacturer hopes
    you assume. That way they need not discuss earthing and hope
    you assume it is a series mode protector. But they are,
    instead, shunt mode protectors. Effective shunt mode
    protectors must be connected short to earth ground. If you
    *assume* it absorbs surges then they can avoid an earthing
    discussion; let myths purveyors promote their ineffective
    product.

    Series mode protectors absorb. Shunt mode protectors are
    similar to electric switches or electric wires - they shunt.
    If others believe that it absorbs, then critical earth ground
    may be overlooked. Essential to selling that ineffective
    protector is to avoid all mention of earthing. And so they
    hope other will *assume* it absorbs. If it shunts, then one
    may ask what it shunts to? Those would be embarrassing
    questions.
     
  11. Ron Reaugh

    Ron Reaugh Guest

    Gibber ignored.
    And this wacko nonsense is from the guy who brought up DA design! At high
    frequency it is most ALL about topology!
    Did you ever hear about the speed of light or about 1 foot per nanosecond?
    Vaporizing...are you gonna bring in Klingons now as we seem to be having a
    bit to drink?
     
  12. Ron Reaugh

    Ron Reaugh Guest


    Right where I said it was as anyone who reads it can see for themselves.
    Gain some technical background before you tackle such technical issues.
     
  13. Ron Reaugh

    Ron Reaugh Guest

    If you'd read my previous post I already said exactly that.
    No, inside a discontinuous Faraday cage....get a clue.
     
  14. w_tom

    w_tom Guest

    Put an impulse down a wire. Where on that wire will the
    impulse voltage first be seen? On the near end where the
    impulse starts? Obviously not. Impulse first appears at the
    far end of wire. How can this be when it takes the impulse 1
    foot per second to get to that far end? Topology as defined
    by Ron would erroneously conclude impulse first appears where
    impulse was first applied to wire.

    Why do we know that topology not relevant? Its a simple
    second year course called E-M fields. One first learned basic
    concepts before promoting rubbish such as topology and
    'faraday cage'.

    Notice that Ron Reugh also cannot provide MOV datasheets to
    demonstrate protection by vaporization. He is typical of
    those who would recommend plug-in protectors. Facts remain
    unchallenged: a surge protector that vaporizes during a surge
    is ineffective and even violates the MOV manufacturer's own
    specifications. Ron's best technical response:
     
  15. w_tom

    w_tom Guest

    IOW there is no claim in that APC sales brochure for common
    mode transient protection. Even worse, they no longer make the
    specific claim for normal mode protection. Ron again
    demonstrates propaganda used to promote plug-in UPSes for
    ineffective surge protection.
     
  16. J.J.

    J.J. Guest


    If a computer PSU fails then I have heard that it may (or may not)
    blow the mainboard and perhaps various other components with a
    power surge or soemthing like that.

    It seems that better PSUs are designed so that when they fail they
    have some circuitry which protects the other components in the PC.

    Is this failsafe feature of the PSU I am referring to pretty much
    the same feature you are referring to? Or are they separate
    features?

    Does anyone know how common it is to get this failsafe feature in a
    PSU?
     
  17. John Gilmer

    John Gilmer Guest

    I'l bite:

    I think I understant FAT systems.

    But the only thing I "think" I know about the NTFS is that, effectively, the
    system first makes a record of what it is about to do, then it does it, and
    then it either erases the original record or somehow marks it.

    SO: can someone "explain" the NTFS to me. (Please don't tell me to "look
    it up.")
     
  18. Mike

    Mike Guest

    Reference Microsoft :)

    "Because you didn't shut down Windows properly, Scandisk is now trashing
    your disk to complete the job.

    In future, always shut down Windows properly"

    Scandisk is not *always* going to pull your nuts out of the fire after a
    power interruption. In fact, it might make things worse :)

    Wouldn't you *expect* data corruption, if the system was writing/about to
    write cached data, and the mains power went off?

    You don't need references to figure out that it's a bad idea to just
    lose power in an uncontrolled way.
     
  19. In sci.physics, w_tom
    <>
    wrote
    Erm, 1 foot per *nano*second. Light speed.

    Perhaps it's somewhat less than that; AIUI electric current
    is along the lines of 2/3 c, but it's still pretty darned
    fast.

    [rest snipped]
     
  20. Ron Reaugh

    Ron Reaugh Guest

    You can't even define "impulse".
    Now you've self contradicted and imploded. Ask Albert.
     
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