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Discussion in 'Electronic Basics' started by PinkFloyd43, May 11, 2008.

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  1. PinkFloyd43

    PinkFloyd43 Guest

    First finally dropped the $$ on the big screen and as I live
    in TX, which typically has huge thunderstorms this time of
    year, when at home I unplug everything I value. I want to
    protect the TV with one of the power strips that advertise
    protection against this type of thing? Any opinions on
    what works and what is pure marketing BS, I do realize
    a direct strike means pretty much everything is done with,
    as what happened to a neighbor last year!

    Thanks!
     
  2. JeffM

    JeffM Guest

    Yup.
    (In the future, have your Subject line describe your problem.)
    The varistor-based devices can improve your odds
    but the arithmetic is just overwhelming--even for a near-miss.
    http://www.google.com/search?q=cach...oules+1000.ft&strip=1#Properties_of_lightning
    The closer the strike, the greater the damage.
    The best protection is to NOT have the highest objects in the skyline
    on YOUR property.
    You reminded me of the old joke
    http://www.google.com/search?q=I.only.have.to.out-run.you
     
  3. bud--

    bud-- Guest

    The best information on surge protection I have seen is at:
    http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.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.
    And also:
    http://www.nist.gov/public_affairs/practiceguides/surgesfnl.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 guide is aimed at those with some technical background. The
    NIST guide is aimed at the unwashed masses.

    If you use a plug-in suppressor, get a major brand with high values.

    And note that all interconnected equipment must to be connected to the
    same plug-in suppressor, or interconnecting wires need to go through the
    suppressor. External connections, like cable, also must go through the
    suppressor. Connecting all wiring through the suppressor prevents
    damaging voltages between power and signal wires. These multiport
    suppressors are described in both guides.

    A plug-in suppressor works primarily by clamping the voltage between all
    wires (power and signal) to the common ground at the suppressor. The
    voltage between the wires going to the TV is safe for the TV.

    A service panel suppressor is a good idea. If there is none, a very
    strong surge will cause arc-over in the panel at about 6000V which dumps
    most of the surge energy to earth. If you have a plug-in suppressor, the
    impedance of the branch circuit to surges (which are basically high
    frequency) greatly limits the current, and thus energy, that can reach
    the suppressor.

    Direct strikes to a house require lightning rods for protection. But
    direct strikes are really uncommon unless you really exposed.
     
  4. w_tom

    w_tom Guest

    Get the long list of numeric specs for that "it provides complete
    protection" power strip. It will list each type of surge AND
    protection from each type of surge.

    Take a $3 power strip. Add some $0.10 parts. Sell that protector
    for $25 or $150. Claim to protect from some ambiguous thing called a
    surge. Provide no numbers that make protection claims. The naive
    will use word association instead of science; 'surge protector' sounds
    like 'surge protection'. The power strip protector never does make
    those protection claims. Show me the numbers.

    What must a power strip protector do to provide surge protection?
    It will stop what three miles of sky could not stop? That silly
    little part will absorb the entire surge energy? Of course not.

    Obviously your telco must disconnect during thunderstorms to protect
    their $multi-million computer. That computer connected to overhead
    wires all over town never disconnects? Correct. They may suffer 100
    surges during every thunderstorm - and no damage. They do this by not
    using plug-in protectors.

    Protection is by doing what Ben Franklin did in 1752. Lightning
    seeks earth ground. Lightning used conductive wooden church steeples
    to obtain earth. Effective protection diverted lightning to earth
    using something more conductive. Same protection applies to your
    telco and to your big screen TV.

    Lightning strikes wires out on the street. What is a good path to
    earth? Incoming on your AC mains, through your TV, and out to earth.
    Effective protection earths before lightning can enter your building.
    Effective protection means everything in your building is protected.
    Effective protector is what your telco does - put the protector where
    lightning enters the building AND make that earthing connection short
    (ie less than 10 feet).

    Again, what does lightning seek? What provides protection? Where
    lightning energy dissipated harmlessly? Inside a power strip
    protector? Of course not. Therefore more responsible companies make
    a 'whole house' protector - ie Cutler-Hammer, Leviton, Intermatic,
    Square D, Kieson, Siemens, GE ... Not on that list is APC,
    Tripplite, Belkin, or Monster Cable.

    Critical to surge protection is a single point earth ground AND a
    short ('less than 10 foot) connection to earth. Your telco does that
    (and does not use power strip protectors). Any facility does earthed
    protectors when lightning damage is not acceptable. In your case, the
    effective (properly earthed) 'whole house' protector costs about $1
    per protected appliance. That power strip protector costs tens (maybe
    100) times more money per effective appliance.

    Review citations from Bud that also show these power strip protector
    problems. On Page 42 Figure 8 of his first citation: a power strip
    too close to appliances and too far from earth ground earths a surge,
    8000 volts destructively, through the adjacent TV. That is what
    protectors do. They don't stop or absorb surges. Protectors divert
    surges to earth. It earth ground is too far away (ie more than 10
    feet as in that figure 8), then surges may be earthed destructively
    through adjacent appliances.

    Bud's second citation is blunt about what an effective protector
    must do on Adobe page 8 of 24:
    All appliances (including that big screen TV) internally contain any
    protection that would work on its power cord. Protection so robust
    that 120 VAC electronics must withstand 600 or 1000 volt transients
    without damage. So that the rare and destructive surge (occurs maybe
    once every seven years) does not overwhelm appliance internal
    protection, earth where destructive surges would enter the building.
    Cable is earthed directly (if properly installed). Telephone wires
    are earthed by the telco (for free). But your AC electric - the most
    common source of destructive surges - has no earthing for all AC
    wires. You must install one 'whole house' protector so that internal
    protection inside that TV (and all other appliances) is not
    overwhelmed.

    Properly earth one ‘whole house’ protector to have same protection
    that the telco uses for their switching computers.

    Every professional citation notes what provides protection. Earth
    ground. Those who promote for plug-in protectors manufacturers (and
    will not admit that conflict of interest) will recommend power strip
    protectors. Notice the profit margins. A $3 power strip with some
    $0.10 parts selling for $150. No wonder your big screen TV salesman
    was promoting that protector so avidly. That ineffective protector is
    where his greatest profits lie.

    A protector is only as effective as its earth ground. No earth
    ground (ie too far away) means no effective protection. Provided were
    examples of companies that provides effective surge protectors.
     
  5. bud--

    bud-- Guest

    Poor w_ can't figure out how plug-in suppressors work. Explained in the
    IEEE guide for anyone that can read and think. Hint: they don't work by
    stopping or absorbing.
    All the companies but SquareD make plug-in suppressors; apparently they
    aren't "responsible".

    For the "best" service panel suppressor, SquareD says "electronic
    equipment may need additional protection by installing plug-in [surge
    suppressors] at the point of use."
    The illustration in the IEEE guide has a surge coming in on a cable
    service. There are 2 TVs, one is on a plug-in suppressor. The plug-in
    suppressor protects TV1, connected to it.

    Without the plug-in suppressor the surge voltage at TV2 is 10,000V. With
    the suppressor at TV1 the voltage at TV2 is 8,000V. It is simply a *lie*
    that the plug-in suppressor at TV1 in any way contributes to the damage
    at TV2.

    The point of the illustration for the IEEE, and anyone who can think, is
    "to protect TV2, a second multiport protector located at TV2 is required."

    w_ says suppressors must only be at the service panel. In this example a
    service panel protector would provide absolutely *NO* protection. The
    problem is the wire connecting the cable entry block to the power
    service 'ground' is too long (a common problem). The IEEE guide says in
    that case "the only effective way of protecting the equipment is to use
    a multiport [plug-in] protector."
    What does the NIST guide really say about plug-in suppressors?
    They are "the easiest solution".
    Provide a source for "must".

    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).
    All can be damaged by high voltages between power and signal wires.
    That is the source of damage in the IEEE example above.
    w_ has a religious belief (immune from challenge) that surge protection
    must use earthing. Thus in his view plug-in suppressors (which are not
    well earthed) can not possibly work. The IEEE guide explains plug-in
    suppressors work by CLAMPING 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 stopping or absorbing). The guide explains
    earthing occurs elsewhere. (Read the guide starting pdf page 40).

    Because w_ is evangelical in his belief in earthing, he uses
    google-groups to search for "surge" to spread his dogma.


    Never seen - a source that agrees with w_ that plug-in suppressors do
    NOT work.

    For reliable information read the IEEE and NIST guides. Both say plug-in
    suppressors are effective.
     
  6. whit3rd

    whit3rd Guest



    Lightning has fast rise times and large currents, and induces
    current in all nearby wires. To really protect a device (your TV)
    requires normal precautions (grounding the house panel)
    so that the TV isn't damaged as your house burns down...

    The induced currents in your house wiring can still cause
    the TV to suffer even if the surge is 'arrested' (shunted to
    ground) at the power panel. A simple plug-through suppressor
    is worthwhile, and the TV power supply undoubtedly has its own
    suppressors in place internally. These shunts MUST be applied
    very near the affected device for best effect. They can
    fail after several surges, so replaceable cheap units work well.

    A third kind of suppression is to use an isolation transformer
    or (at lower cost) one or more 'clamp chokes' on the power cord.
    These aren't shunts, but rather are intended to act as series
    elements,
    which means they simply reflect a damaging surge (to other devices
    in your house, like motors and heaters, which are less sensitive).
    A ten-pound transformer of copper and iron can take lots of surge
    energy without damage, and has excellent blockage of
    fast-rising (surge) signals. An ounce of ferrite clamped over
    the cord won't absorb as much, but reflects surges like a mirror
    reflects light.

    The best suppressors use shunts, series elements (and fuses),
    and come with a warranty against damage. Shunt device failure is
    flagged with lights (or by blowing the fuses) and means
    replacement or factory rebuild is due.
     
  7. w_tom

    w_tom Guest

    whit3rd forgets what creates an induced surge. Protectors earth
    surges. Either the surge gets earthed before entering the building,
    or the surge gets earthed by adjacent plug-in protector. Later - that
    ground wire - *induces* surges on adjacent wires. This is effective
    protection? Of course not - and why high reliability facilities don't
    use plug-in protectors that can even induce surges on other wires.

    Whit3rd claims protectors somehow absorb surges. Show me. Where
    are these numbers? Protection is not by absorbing surges as Whit3rd
    posts. Where is this protector that claims to stop lightning by
    absorbing? And where are those numbers? Whit3rd does not answer any
    of those questions for good reason. The effective protector does not
    earth surges. An effective protector diverts surges to be absorbed in
    earth ground. And an effective protector does not induce surges onto
    other appliances.

    Either a surge gets earthed by a 'whole house' protector or the plug-
    in protector futilely earths a surge via same earth ground. Why? If
    earth ground was not desirable via a 'whole house' protector, then why
    is earth ground desirable via a plug-in protector? Obviously the plug-
    in protector adds nothing useful. How do high reliability facilities
    get better protection? Upgrade earth ground. Either that surge does
    not enter a building due to better earthing; or that surge enters a
    building to induce surges everywhere.

    Finally, if using basic electrical knowledge, then he would have
    never posted:
    More reasons why whit3rd has posted naively. a) Fuses take
    milliseconds to open. Surges are done in microseconds. 300
    consecutive surges could do damage and that fuse would not blow. b)
    Furthermore what is the voltage rating on that fuse? Surge would
    simply keep conducting through a blown fuse. Another number that
    whit3rd forgot to learn. Facts that whit3rd should have known. A
    fuse is not surge protection. Obvious if whit3rd had learned the
    science (the numbers). Fuses don't provide surge protection made so
    obvious when one learns the numbers.

    A surge that is earthed before entering a building does not created
    induced surges. A plug-in protector too far from earth ground creates
    induced surges. We properly size a 'whole house' protector. Then
    enhance its earthing. Why? A protector is only as effective as their
    earth ground.
     
  8. bud--

    bud-- Guest

    If poor w_ was able to read and think, he would know from the
    explanation in the IEEE guide that plug-in suppressors work by CLAMPING
    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
    stopping or absorbing). The guide explains earthing occurs elsewhere.
    (Read the guide starting pdf page 40).
    I agree that fuses do not provide surge protection.

    Transformers with a shield between primary and secondary may block
    common mode surges, but do not block transverse mode surges.

    The most common surge protection uses MOVs for power wiring and other
    voltage clamps on signal wires.
    w_ completely misses whit’s point that a near lightning strike can
    directly induce a surge into the house wiring, with the wiring acting as
    a long wire or loop antenna. A service panel suppressor does not provide
    protection from this direct induction.
    The required statement of religious belief in earthing.
    The IEEE guide explains plug-in suppressors work primarily by clamping,
    not earthing.

    Still never seen - a source that agrees with w_ that plug-in suppressors
    do NOT work.

    For reliable information read the IEEE and NIST guides. Both say plug-in
    suppressors are effective.
     
  9. neon

    neon

    1,325
    0
    Oct 21, 2006
    a direct strike to the biulding will probably raise the biulding to a couple of kv, protection sure run a real heavy wire from your house to earth. electrical substation have these fetures it helps but it is not bullet proof. comercialy you can waist money to protect your line form something coming along the line not to stop an electrical discharge from the sky to earth . unplug a TV is a good idea or move to a better state.
     
  10. w_tom

    w_tom Guest

    The plug-in protector promoter (who forgets to acknowledge what he
    does) now says a protector works by 'clamping to nothing'. As every
    responsible source says, effective protection is by clamping
    (diverting, connecting, shunting) surges into earth. Where is that
    surge energy dissipated? Bud says that energy magically disappears -
    'clamping to nothing'. Responsible sources say surge energy, well,
    lets quote directly from a Bud source ....
    NIST does not say anything about 'clamping to nothing'. NIST is
    quite bunt about what provides protection ... "diverting the surges to
    ground".

    If we install effective protectors, then massive profits in those
    plug-in protectors disappear. How massive? Take a $3 power strip.
    Add some $0.10 parts. Sell it for $25 or $150. With profits that
    large, why would Bud be honest? No wonder he posts insults; forgets
    to provide a single manufacturer spec that claims protection. Oh?
    Did Bud again forget to post a spec? He cannot. Protectors that
    'clamp to nothing' do not list protection from each type of surge. If
    the protector cannot make that claim, well, either does Bud. Insults
    rather than specs are how Bud promoted ineffective products.

    Why does that flat screen salesman expend so much time and effort
    promoting a $150 plug-in protector? View the profit margin; another
    fact that Bud hopes you will ignore.

    Effective protectors make that 'always necessary' short connection
    to earth ground. How curious. Even Bud's citations define that
    earthing requirement. 'Clamping to nothing' accomplishes nothing. But
    it is profitable.
     
  11. bud--

    bud-- Guest

    To quote w_ "It is an old political trick. When facts cannot be
    challenged technically, then attack the messenger." My only association
    with surge protectors is I have some.

    But with no technical arguments, w_ has to discredit those that oppose him.

    Still never seen - a source that agrees with w_ that plug-in suppressors
    do NOT work.

    Never answered - embarrassing 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"?

    For real science read the IEEE and NIST guides. Both say plug–in
    suppressors are effective.
     
  12. w_tom

    w_tom Guest

    Bud cannot provide a single plug-in manufacturer's spec that claims
    protection. 500 requests for those specs and Bud still refuses. Bud
    promotes protectors that do not even claim to provide protection. A
    $3 power strip with some $0.10 parts selling for $25 and $150. To
    protect those profit margins, Bud will post insults.

    Effective protectors with a dedicated wire to earth ground have
    responsible names such as Intermatic, Siemens, Keison, Cutler-Hammer,
    Leviton, Square D and GE. Not on that list are APC, Tripplite,
    Belkin, and Monster Cable. How to see why? How to identify an
    ineffective protector? 1) No essential and required earth ground
    wire..2) Manufacturer (and Bud) avoids all discussion about earthing.

    Both NIST and IEEE citations from Bud bluntly state, "The best
    surge protection in the world can be useless if grounding is not done
    properly." Bud says no earthing is required.

    No earth ground means no effective protection. Effective protectors
    are typically connected less than 10 feet to earth ground. Shorter
    means even better protection. An effective 'whole house' protectors
    costs about $1 per protected appliance. Why spend $25 or $150 per
    appliance for protectors without earth ground and recommended by Bud?
    Bud will not even provide a manufacturer spec. He cannot. Plug-in
    protectors do not claim to protect from the typically destructive
    surge. So Bud posts insults.
     
  13. bud--

    bud-- Guest

    Provided often and ignored.
    w_ has a religious belief (immune from challenge) that surge protection
    must use earthing. Thus in his view plug-in suppressors (which are not
    well earthed) can not possibly work. The IEEE guide explains plug-in
    suppressors work by CLAMPING 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 stopping or absorbing). The guide explains
    earthing occurs elsewhere. (Read the guide starting pdf page 40).


    Still never seen - a source that agrees with w_ that plug-in suppressors
    do NOT work. It is just w_’s opinion based on his religious belief in
    earthing.

    Still never answered - embarrassing 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"?

    For real science read the IEEE and NIST guides. Both say plug–in
    suppressors are effective.
     
  14. sparky

    sparky Guest

    Tom: Many surges are from line to neutral. A plug-in surge protector
    will prevent these from damages the protected equipment. Earth
    ground
    provides a better degree of protection but a good level of protection
    can be realized without an earth ground
     
  15. w_tom

    w_tom Guest

    Those 'surges' are typically so trivial as to be considered noise.
    Protection inside all appliances makes that 'line to neutral' surge
    irrelevant. Have you read those numbers? Internal 120 v appliance
    protection starts at 600 volts, is said by Bud to be 800 volts, is
    required by Intel specs to be 1000 volts ... Did you know these
    numbers that make 'line to neutral' surges irrelevant? Are you
    replacing dimmer switches daily or weekly due to this surge? Of
    course not. Even dimmer switches have sufficient protection to make
    that 'surge' irrelevant.

    What does the 'whole house' protector also make irrelevant? The
    'line to neutral' surge. The 'whole house unit protect from all type
    of surges including 'line to neutral'.

    Meanwhile, what are the typically destructive surges? From Bud's
    IEEE citation Page 42 Figure 8 - the plug-in protector earthed a
    surge, 8000 volts destructively, via the adjacent TV. Which type of
    surge is typically destructive? Notice which type of surge applied
    8000 volts to a TV with a plug-in protector (no earth ground)
    connected adjacent. Let's see. The typically destructive surge
    arrives at a plug-in protector and TV. Therefore 8000 volts destroys
    the TV. That plug-in protector did exactly what its manufacturer
    claimed.

    A plug-in protector only claims to protect from surges that
    typically do not cause damage. A 'line to neutral' surge is made
    irrelevant by one 'whole house' protector. Typically destructive
    surges are also made irrelevant by the same one 'whole house'
    protector.

    What is provided by a protector without earth ground. Zero
    protection from surges that typically cause damage. What does a plug-
    in protector do? It does not and does not even claim to protect from
    the typically destructive surge. It only protects from surges made
    irrelevant by protection already inside appliances AND it does not
    (cannot) protect from typically destructive surges.

    Without earth ground means no protection from typically destructive
    surges. A protector is only as effective as its earth ground. Those
    protectors protect from all types of surges. How to identify
    ineffective protectors? No connection for that short (ie less than 10
    foot) earthing wire.
     
  16. bud--

    bud-- Guest

    I say -immunity- is -typically- -600-800V-. There is no requirement that
    immunity is as much as 600V. Immunity is not necessarily by "protection".

    Damage is more likely from high voltage between power and signal wires.
    The *lie* repeated. The plug-in suppressor reduces the voltage at a
    second TV (which is not adjacent).

    The point for the IEEE, and anyone who can think, is "to protect TV2, a
    second multiport protector located at TV2 is required."

    A service panel suppressor would provide absolutely *NO* protection. The
    problem is the surge comes in on the cable service, and the 'ground'
    wire connecting the cable entry block to the power service ‘ground’ is
    too long. The IEEE guide says in that case "the only effective way of
    protecting the equipment is to use a multiport protector."
    The type of surge is one coming in on a cable service. A service panel
    suppressor would provide absolutely NO protection.

    As I previously posted, the NIST guide indicates the most common damage
    is from high voltage between cable/phone wires and power wires (as in
    this example).

    As a result the NIST guide says:
    "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."
    Complete nonsense.

    Plug-in suppressors have MOVs from H-N, H-G, N-G. That is all possible
    combinations and all possible surges.

    If a surge arrives with H & N elevated above G (common mode) the voltage
    from H-G will be clamped by a MOV, the voltage from N-G will be clamped
    by another MOV. The voltages between wires to the protected equipment
    are safe for the protected equipment.

    If there are other wires like phone or cable, they also have to go
    through the suppressor. The voltage on the signal wires is also clamped
    to the common ground at the suppressor. The voltage between all wires
    going to the protected equipment is safe for the equipment.

    The surge is not necessarily earthed effectively by the suppressor
    ‘ground’ wire, but earthing occurs elsewhere in the system. In the IEEE
    example, the surge is earthed by the cable entry protector ‘ground’
    wire. (Read the example in the IEEE guide starting pdf page 40.)

    Properly connected plug-in suppressors are likely to protect from
    anything but a very near lightning strike. With high ratings, they are
    likely to also protect from that. The impedance of the branch circuit to
    a surge greatly limits the current, and thus energy, that can reach a
    plug-in suppressor.
    The required statement of religious belief in earthing. Everyone is for
    earthing. But the IEEE guide explains plug-in suppressors work primarily
    by clamping, not earthing.

    Still never seen - a source that agrees with w_ that plug-in suppressors
    are NOT effective.

    Still never answered - embarrassing 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"?

    For real science read the IEEE and NIST guides. Both say plug–in
    suppressors are effective.
     
  17. Ken

    Ken Guest

    That's true that effective surge protection must use earthing.
     
  18. sparky

    sparky Guest

    Not all equipment comes with a grouded cord. Plugin protectors will
    protect this equipment equally as well as a grounded protector.
    The protection will be almost as good as a whole house protector.
     
  19. w_tom

    w_tom Guest

    At no time was the safety ground on an appliance even relevant.
    Does not matter whether an appliance has two or three wires (since
    that third wire is not earth ground). A surge can find earth ground
    destructively through that appliance. A plug-in protector can even
    make that damage easier.

    Plug-in protectors can even contribute to damage of the adjacent
    appliance. That is the point of a Bud citation - Page 42 Figure 8.
    The adjacent TV (even a two wire TV) suffered 8000 volts because the
    nearby plug-in protector earthed that surge through the TV. Once a
    surge is permitted inside a building, then destructive paths to earth
    can exist most anywhere.

    Again, where surge damage is not acceptable, one 'whole house'
    protector is installed and properly earthed. Properly? Numbers such
    as 'less than 10 feet' to earth ground are relevant. Why? Wire
    impedance.

    Two 'top of the front page' articles in Electrical Engineering Times
    discuss what and whys. Both articles are entitled "Protecting
    Electrical Devices from Lightning Transients". So the article
    discussed plug-in protectors? Of course not. This is science for
    engineers - not myths for retail salesmen. The article discusses
    earth ground and other important numbers such as why that earthing
    wire must be short (ie 'less than 10 feet'). Since they are
    discussing effective protection, then plug-in protectors are not
    discussed.

    The effective 'whole house' protector means massive protection.
    Well, it is not perfect. IEEE Green Book puts numbers to imperfect
    (properly earthed) protection:
    We install one 'whole house' protector (properly earthed) so that
    every of maybe 100 electronics appliances (including more important
    electronics like smoke detectors and bathroom GFCIs) are not damaged.
    Protection that is imperfect using numbers such as 99% effective - if
    properly earthed.

    How to have massive surge protection in a house that only has two
    wire circuits? Exact same 'whole house' protector with earthing at
    the breaker box, upgraded to exceed post 1990 National Electrical Code
    requirements. Nothing even says replacing the breaker box. We
    simply install one 'whole house' protector and earthing. Now even two
    wire appliances have effective protection - far beyond what any plug-
    in protector claims to provide.

    A protector is only as effective as its earth ground. No earth
    ground (ie plug-in protectors) means no effective protection.

    Did another forget to mention that a plug-in protector is
    ineffective without a 'whole house' protector? Of course not. If he
    did, you might learn why earthing provided protection. Then his
    profits would be at risk. A protector is only as effective as its
    earth ground. No earth ground means no effective protection. At what
    point should we ignore damning engineering numbers?
     
  20. sparky

    sparky Guest

    Return to Federal Citizen Information Center Home Page

    Decisions, decisions

    Surge protectors come in many shapes and forms for many purposes, not
    just the plug-in kind that you find in the electronic stores. There
    are several ways to install them on your power supply: plug and play,
    do-it-yourself, hire a licensed electrician to do it, or even call on
    your power company to do it. Here is a run down on your options, and
    who does it:

    Purchase one or more plug-in surge protectors
    Install a surge protector at the service entrance panel
    Have the power company install a surge protector next to the meter
    Plug-in surge protectors

    This is the easiest solution, and there is a wide variety of brands
    available in the stores (as we noted at the start of this booklet, we
    are not going to recommend brands). These come in two forms: a box
    that plugs directly into a wall receptacle, or a strip with a power
    cord and multiple outlets. Depending on the appliance, you will look
    for a simple AC power plug-in, or a more complex combined protector
    for AC power and telephone or cable -more on that later. However,
    before you purchase the right protector for the job, you should think
    about some details.

    There is another decision to make, concerning how a surge protector
    will power your appliance if the protective element should fail under
    extreme cases of exposure to a large surge or large swell. Most surge
    protectors are provided internally with some kind of fuse that will
    disconnect in case of failure. However, this disconnect can operate in
    two different ways, depending on the design of the surge protector:
    some will completely cut-off the output power, others will disconnect
    the failed element but maintain the power output.

    Quit and be protected or continue?

    For you, it is a matter of choice: would you want to maintain the
    output power to your appliance -but with no more surge protection? Or
    would you rather maintain protection for sure -by having the circuit
    of the protector cut off the power supply to your appliance, if the
    protective function were to fail? To make an intelligent decision, you
    must know which of the two possibilities are designed into the surge
    protector that you will be looking for.

    What are the lights telling you?

    To help the consumer know what is going on inside the surge protector,
    many manufacturers provide some form of indication, generally by one
    or more pilot lights on the device. Unfortunately, these indications
    are not standardized, and the meaning might be confusing, between one,
    two - even three or four lights -where it is not always clear what
    their color means. Read the instructions!

    More decisions ...

    So far, we have looked mostly at the plug-in surge protectors because
    they are the easiest to install and they do not require the services
    of an electrician. The two other possible locations for surge
    protectors are the service panel (breaker panel) and the meter
    socket.

    Service-panel surge protectors

    Instead of using several plug-in protectors -one for each sensitive
    appliance is sometimes recommended -you can install a protector at the
    service panel of the house (also called "service entrance" or "breaker
    box"). The idea is that with one device, all appliances in the house
    can be protected, perhaps with a few plug-in protectors next to the
    most sensitive appliances. There are two types of devices available:
    incorporated in the panel, or outside the panel.

    Some breaker panel manufacturers also offer a snap-in surge protector,
    taking the space of two breakers (assuming that there are blank spaces
    available on the panel), and easily installed by the home owner or by
    an electrician. However, there are two limitations or conditions to
    that approach:

    The snap-in protectors generally fit only in a breaker panel from the
    same manufacturer -possibly down to the model or vintage of the
    panel.

    To install the snap-in protector, you must remove the front panel (do
    turn off the main breaker before you do that i). Most cities have
    codes allowing the home owner to do it, under some conditions. Check
    with your local authorities to find out if they allow you to do that,
    or hire a licensed electrician to do the installation for you.
    There are other surge protectors packaged for wiring into the service
    panel, either within or next to the panel. That kind of installation
    is best left to a licensed electrician.

    At the meter socket

    There might be a possibility that the power - company in your area
    offers, as an option, to install a surge protector with a special
    adapter, fitting it between the meter and its socket (the dark band in
    the bubble of the picture). But that type of device and installation
    is out of the question as a do-it-yourself project, and will require
    cooperation from the power company, if they do offer the program.

    Other types of outdoor surge protectors can be installed near the
    meter. That kind of installation must be done by a licensed
    electrician.


    http://www.pueblo.gsa.gov/cic_text/housing/surge/decisions.htm
     
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