Whole house surge suppressors

Peter_V
Peter_V Solar Expert Posts: 226 ✭✭✭
The EMP thread got me thinking again about protecting my systems from nearby lightning strikes.

When the array was installed the electrician wired in a lightning suppressor at the PV cutoff switch (the round can sticking out the bottom).
Suppressor.jpg

However, I don't think this will protect the rest of my house so I was thinking of installing a Leviton 51110-1 SPD:
http://www.amazon.com/gp/product/B002VJKAZS

What to you guys think, will this be adequate or should I use a different brand/model?

FWIW The majority of my electronic devices (computers, TVs, etc.) will also have a plug in surge suppressor and/or UPS.
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Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Whole house surge suppressors

    A whole house surge suppressor should help (basically short circuit surge voltage spikes to ground and will trip the main breaker for larger current flows). So--In some ways, the whole home surge suppressor will make your AC power a bit less reliable (tripping main breaker with surges) with the possibility that you will save your home appliances.

    If you are in an area that can get direct lightning strikes, I am not sure that these will do much in the way of protection. A direct strike just has too much energy/voltage/current.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Whole house surge suppressors

    I have a whole-house Leviton, it has 2 monitor LEDs and is mounted below one of my panels. Always hard to say if it has really saved me, but I know we've had one lightning strike a few years ago within 60 feet of my service panels & ground rod, about 20 feet from my pad transformer, and the only thing that fried was my DirecTV dish (which was also about 20 feet in another direction from the tree that was hit). We've had several other very close strikes but I have no idea how close. We are on the rocky edge of a ridge, and rocky edges of ridges are known to attract strikes. The prior owner of our house lost the well pump about 10 years ago before he installed the Leviton.

    The one you already have will protect your house, its all on the same AC legs. The question is if its large enough.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Whole house surge suppressors

    The surge suppressor on the solar gt branch circuit will probably trip the branch circuit breaker.

    A suppressor on the main panel should trip the disconnect instead. So that should be a worth while addition to your home even if you already have the other suppressor.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Sparkletron
    Sparkletron Solar Expert Posts: 71 ✭✭✭✭
    Re: Whole house surge suppressors

    I would definitely install one. If you do, make sure you get one with an LED or something to indicate it's functioning. They're only good for so many transients and then they stop working.
  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    Peter_V wrote: »
    When the array was installed the electrician wired in a lightning suppressor at the PV cutoff switch (the round can sticking out the bottom).

    However, I don't think this will protect the rest of my house so I was thinking of installing a Leviton 51110-1 SPD:
    Your answers starts with some basic concepts. And numbers. First, no protector is protection. You are not the only one here who completely missed the point. Destructive surges seek earth ground. Either that energy dissipated harmlessly outside the building. Or it is inside hunting for earth destructively via appliances. You select Option A or Option B.

    Option B is what most everyone has. A direct lighting strike to wires down the street would be a direct strike to household appliances. Surge damage means direct strikes with the same current both incoming on one wire. And outgoing on another wire of that appliance. The only protection means that current is earthed before it enters the house.

    The most important component of every protection 'system'. And nobody even mentioned it? Single point earth ground.

    Either a 'whole house' protector connected every single wire in every cable to earth (or that wire connects directly to earth - ie cable TV). Or all protection is compromised. Protection means every wire connects short (ie 'less than 10 feet') to earth. Or the protection system is ineffective.

    AC is three wires. All three must be earthed. Two via a 'whole house' protector. Telephone is two wires. Both must connect to earth before entering. Every telephone subscriber interface already has that 'whole house' protector.

    You had satellite dish damage because the earthing somewhere was defective. That satellite dish must enter at the service entrance (with telephone and AC electric) to make a direct (ie 'less than 10 foot') connection to the same earth ground electrode. And the dish itself must be earthed. Either a direct lighting current goes to earth via the dish (not via LNB). Or you have damage.

    Protection is always about an electric current path to earth. A 'whole house' protector means protection for everything inside. Protection means no energy anywhere inside a building. A plug-in protector sometimes makes surge damage easier.

    The nearby strike? Well, a long (100+ feet) wire antenna was tens of feet from a lightning strikes. So thousands of volts appeared on its incoming lead. We put an NE-2 neon glow lamp (same is inside nite glowing wall switches) from that antenna lead to earth. Then the thousands of volts was only tens of volts. The energy content of nearby strikes is almost zero. So milliamps through an NE-2 result in a massive voltage reduction. Worry not about nearby strikes. Worry about the actual current (typ 20,000 amps) from a direct lighting strike. A strike to AC wires (overhead or underground) down the street is a direct lightning strike to every household appliance.
  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    I would definitely install one. If you do, make sure you get one with an LED or something to indicate it's functioning. .
    The LED can only indicate a type of failure that means the protector was ineffective - grossly undersized.

    Yes, the protector is good for a limited number of transients. So it should still be effective a decade later. Which means it must earth direct lightning strikes and still remain functional. Failing protectors are how grossly undersized and obscene profit protectors get promoted by the uninformed to the naive.

    Effective protection means nobody knew of a surge. Means the most uninformed do not recommend it. Even the protector remains functional after a lightning strike because nobody should know a surge existed. Just another reason why the majority do not recommend a proven 100+ year solution. The LED can only indicate a type of failure that must not happen.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Whole house surge suppressors

    westom, I'm the one that had satellite dish damage but I'm not the OP.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • thehardway
    thehardway Solar Expert Posts: 56 ✭✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »

    The most important component of every protection 'system'. And nobody even mentioned it? Single point earth ground.

    I can't agree more. Although I'm not an expert on wind and solar, I have built communications towers and installed commercial telecommunications networks. A single point ground is the best way to protect your system from lightning related problems.

    Most locations which are experiencing equipment losses during electrical storms have multiple ground paths and potential differences within the grounding system.

    A common one you will find is in older homes where the telco required a ground connedtion to the cold water pipe, and a separate ground outside from the AC power. I can't tell you how many computers, phones, and modems were fried by electrical power surges through the unit to get to the ground on the telco side. In some cases the surge may come through the telco side. Ditto for cable systems, towers, antennae and any other device connected into or through the home.

    All grounds should be tied back to a single point which is located at the main panelboard entrance and bonded to the neutral busbar. If more than one grounding rod is used it should be bonded back to the main entrance ground so that there is zero potential between the grounding points.

    It is important to note that there are different types of grounding for different purposes. Bodily hazard/safety grounds, ESD grounding, EMF grounding, isolated grounds, logic grounds, and lightning grounds are all slightly different and have different requirements. Often these are confused and as a result, data can be scrambled memory lost or wiped, circuits damged or in worst cases a person killed or disabled due to improper grounding.

    A surge suppressor will not solve any problems if your grounding is not done properly. Cutler Hammer produces a whole house surge protector CHSP Micro available for around $50.00 which offers a $25,000.00 connected load warranty when used in conjunction with a point of use surge protector and will stop surges up to 36kA step up is the CHSP Ultra which is good for up to 50kA
    for around $125.00 they carry a Lifetime Warranty.

    Also important is maintaining good ground conductivity around electrodes. If the electrode is in excessively dry earth or the earth has high capacitance or poor conductivity due to composition you may need to use a conductive solution to saturate the soil around it.
  • JESSICA
    JESSICA Solar Expert Posts: 289 ✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    The most important component of every protection 'system'. And nobody even mentioned it? Single point earth ground.
    .

    Why "single point"?
    How and why is a "single point" earth ground better or more effective than multiple grounds rods?
  • arkieoscar
    arkieoscar Solar Expert Posts: 101 ✭✭
    Re: Whole house surge suppressors

    Are these using MOV's or has some other device replaced them?
  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    JESSICA wrote: »
    Why "single point"?
    How and why is a "single point" earth ground better or more effective than multiple grounds rods?
    Lightning struck a tree some 30 feet from a horse. So the horse died from a direct lightning strike. Ok. It is electricity. So you know this. There was an incoming electrical path. And an outgoing electrical path. A critical fact that everyone knows from school science.

    Lightning is a connection from a cloud to earthborne charges maybe five miles away. What is a shortest connection? Three miles down to a tree. And four miles in earth to those charges. A shortest path was also up the horse's hind legs and down its fore legs. Horse was also in a shortest path from cloud to charges. Horse died because it did not have a single point ground.

    Humans do same. During a lightning storm, keep feet together. Single point ground. Lightning is incoming via legs. But has no outgoing path; no outgoing current. No death.

    Same applies to protecting appliances in a house. BTW, did some scummy salesman have you thinking protection is a magic box next to an appliance? Protection is about viewing the entire house and nearby items - ie overhead utility wires, cloud, etc.

    Single point ground is why static discharge to an Ipod does not destroy it. Why barns have a buried copper wire loop so that cows are not killed. Why golfers stand with feet together during a storm. And why a home without single point earth ground earths surges via household appliances.

    If any wire enters a structure without first connecting to that earth ground, then that structure has no effective protection. Even applies to a satellite dish.

    This is science from over 100 years ago. And is completely unknown to so many educated only by advertising and hearsay.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    ........

    If any wire enters a structure without first connecting to that earth ground, then that structure has no effective protection. Even applies to a satellite dish.

    This is science from over 100 years ago. And is completely unknown to so many educated only by advertising and hearsay.

    How do you manage several wide spread structures fed from 1 meter? The simple house & 1 ground is easy. How about a power pole, 100' to a workshop, and another run (star, not daisy chain) 200' to a house (house and shop are 300' apart, how do you ground that ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

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  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    mike90045 wrote: »
    How do you manage several wide spread structures fed from 1 meter?
    A professional application note demonstrates single point earthing. Two structures. Each must have a single point ground. Any wire entering but structures must connect to that structures single point ground before entering:
    http://www.erico.com/public/library/fep/technotes/tncr002.pdf

    Earthing requirement applies to every wire in every cable. Even if that cable is underground.

    If two structures violate the concept, then a direct lightning strike to one building may become a lightning rod connecting that surge into appliances inside the second building.

    Earthing wires to some 3 meter ground rods means a massived increase in surge protection. But better informed builders start protection when footings are poured. Ufer grounds were pioneered in munitions dumps so that direct lightning does not cause explosions. Technology is that routine when surge damage is not acceptable. Effective because concrete is a good electrical conductor.

    Buried ground loop is another solution. Or how one solve earthing atop a rocky mountain:
    http://scott-inc.com/html/ufer.htm

    A case study of how all surge damage was eliminated in a Nebraska radio station by not wasting money on protectors. By fixing defects - bad earthing. They even fixed the utility pole transformer earth ground. Each layer of protection is only defined by that earthing electrode - each single point ground; not by any protector:
    http://www.copper.org/applications/electrical/pq/casestudy/nebraska.html

    Welcome to what advertising and salemen in a big box TV / computer store will not discuss to enrich themselves at your expense.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    A shortest path was also up the horse's hind legs and down its fore legs. Horse was also in a shortest path from cloud to charges. Horse died because it did not have a single point ground.

    Humans do same. During a lightning storm, keep feet together. Single point ground. Lightning is incoming via legs. But has no outgoing path; no outgoing current. No death.

    Several incorrect pieces here.

    First, it has nothing to do with "shortest path", it has everything to do with "path of least resistance". The distance between a horse's hind legs and forelegs as he stands on the ground is the shortest path, but the dirt between his legs may have a high resistance, with a far lower resistance through his saltwater-filled blood and tissues (saltwater is a great conductor). So the current may travel up his hind leg, across his heart and down a fore leg. More on the heart thing later.

    Next, keeping your feet together will protect you from the high voltage difference that will exist in the ground between your feet during a lightning strike (you could have thousands of volts of difference in just a few inches, which would then conduct up one let and down another because of the voltage potential). But even if you stand with your feet apart and the lightning travels up your leg it will most likely just cross your groin and travel down your other leg. This is why the rule of thumb for working inside a live service panel (many electricians do, you don't need to tell me they shouldn't, I know) is to keep one hand behind you at all times. If you do touch a live circuit and a ground path at the same time the current will just travel up one finger, across your hand and then down the other finger. The key - whether we are talking legs or fingers - is to prevent a path across your heart. Crossing the groin will hurt like hell and could cause serious damage but it won't kill you.

    Which brings me to my final point. Doesn't matter if you stand feet apart or feet together because most likely the lightning will directly contact another appendage like your head or arms and then you DO have a path across your heart. So a golfer should get inside an enclosed shelter and not stand with his feet together in the middle of a field.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • thehardway
    thehardway Solar Expert Posts: 56 ✭✭✭✭
    Re: Whole house surge suppressors

    As I mentioned, there are many types of grounding for many different purposes and bodily hazard grounding is a discipline all of its own, although it is the ugly one most people often experience "first hand" pun intended.

    If you really think about it, a "path of least resistance" has very little to worry about. The electrical current will pass through it with very little resistance and very little effect with very little surge or rise. It is the "path of some resistance" that causes problems. It is here that arcing, burning, and "shocking" occur. A "shock" is merely a rapid rise or surge current. There is electricity coursing through your body at all times. It is harmless. It is what makes your heart, brain and nervous system function. Death does not occur from electricity merely passing through your body. It comes from a surge or rapid rise or over-current. If your body presents too much resistance in the path there will be a rapid rise or "shock" which occurs or even burning.

    Remember the electric fence trick. Five kids hold hands in a line, the one at one end grabs an electric fence. The one who grabs the fence does not feel a shock, nor do those in the middle, it's the poor little kid on the other end that doesn't know what's being planned for him that gets whacked.

    A mild electric surge in the body can cause the heart, brain, or nervous system to malfunction or death to occur, a large surge or arc can cause burning or even vaporize the body.

    Just like a filament in light bulb. If you stay within the allotted voltage it works fine. If the resistance is too great for the increase in voltage, pow! The filament burns and if the voltage is high enough to arc within the bulb the whole bulb will explode.

    More people die from a result of burns when electrocuted than do from current.

    ESD grounding is a different discipline and the single point ground iPod illustration does not exactly apply. An electrostatic discharge to a specific portion of an iPod could result in a total loss regardless of whether or not there was a single point ground to the device. Even the arc caused by electrostatic discharge generates an electromagnetic field which of its own could cause damage to components.

    All grounding disciplines come back to the same issue. Equalizing potential. If a person is grounded to the same plane as the iPod they touch there will be no discharge. This is the reason electrical component assembly workers wear ESD straps which are grounded to the same plane and the assembly they are working on. In many cases they will actually seek to isolate them from earth grounds or other magnetic fields.

    Equalized potential is the reason single point grounding works for protection where multiple grounds do not.

    Shortest path to ground as previously mentioned is not a path determination for lightning or arcing. Watch some slow-mo videos of arc flash if you don't believe this.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Whole house surge suppressors

    Lighting has significant radio frequency energy content... So you have to look at the "impedance" and not simple resistance. Becomes a much different beast than DC / low frequency resistance calculation.

    A few older lightning threads here:

    Off Grid Grounding Technique?
    Another Question, this time about Lightning

    Note, the above are discussions, not a do A, B, and C--and you will be "safe". There probably is no such thing with lightning. Several different techniques are discussed--and a few of those posters even have experience with lightning. :cool:

    And our host's consolidated FAQ page:

    www.windsun.com
    Lightning Protection for PV Systems

    From other past posts here, Windsun (admin/owner of NAWS), he said that most of lighting induced failures he saw were in the Inverters' AC output section.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    techntrek wrote: »
    Several incorrect pieces here.
    The question was about single point ground functions and why. Your post makes no sense by completely ignoring Jessica's question, the context, and purposes of earthing.

    An electrically shortest path is not "path of least resistance". Read what BB posted. Path of least "impedance" (radio frequencies) is important. Involves other factors including and not limited to a conversion of gas to plasma. Other factors were irrelevant to Jessica's question.

    A shortest electrical path is not five miles across sky. Shortest path is down to a tree. Then through earth. That example demonstrates an answer to Jessica's question. And why superior surge protection best begins when footing are poured.

    Jessica's question was about single point ground. Where does your post answer questions by Jessica or mike90045? Whether the electrician keeps one hand in his back pocket (a good practice) or not is irrelevant.

    Back to what others are discussing.

    Equalized potential discussed by thehardway is part of a solution. Single point earth ground must do two things: equipotential and conductivity. Since conductivity cannot be made sufficient, then we also need equipotential. And since equipotential is not sufficient, then we need better conductivity. Both electrical concepts are what make a 'whole house' protector so effective. And why a protector inside a building (too close to appliances) is ineffective.

    Protection is always about an electrical current path to earth; not about voltage. That means a lowest impedance (not resistance) path. Impedance is why the connection must be so short (ie 'less than 10 feet') without sharp wire bends, no splices, not inside metallic conduit, and separated from other non-grounding wires. More reasons why plug-in protectors do ineffective protection.

    Concepts of conductivity and equipotential are engineering reasons. For a layman, that translates to single point earth ground, a shortest path to earth either directly (from cable TV) or via a protector (AC electric, telephone), every wire in every cable (even if underground) connected to that ground, and where energy dissipates.

    Anything that would protect inside a house means energy is inside and hunting destructively for earth via appliances. Means that protector sometimes makes damage easier. Anything inside to make energy magically disappear is a myth. Protection is always about 'diverting' surges on a harmless path to earth.

    Peter V asked, "The EMP thread got me thinking again about protecting my systems from nearby lightning strikes." Worry not about EMP. The horse was not killed by EMP. Protection for everything inside a house is the actual current path. The horse did not have single point ground; so was killed. The NIST (US government research agency) says what all effective protectors do:
    > You cannot really suppress a surge altogether, nor "arrest" it. What these protective
    > devices do is neither suppress nor arrest a surge, but simply divert it to ground, where
    > it can do no harm.

    "Divert". Protection is always about the current path. Effective protection means current is not inside a house and does not create a high voltage. That current will flow not matter what tries to stop it. Only fools, retail salesmen, and myths stop or block surges. Protection is always about where energy dissipates. Every protector is only as effective as the relevant topic here: single point earth ground.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Whole house surge suppressors
    thehardway wrote: »
    If you really think about it, a "path of least resistance" has very little to worry about. The electrical current will pass through it with very little resistance and very little effect with very little surge or rise. It is the "path of some resistance" that causes problems. It is here that arcing, burning, and "shocking" occur. A "shock" is merely a rapid rise or surge current. There is electricity coursing through your body at all times. It is harmless. It is what makes your heart, brain and nervous system function. Death does not occur from electricity merely passing through your body. It comes from a surge or rapid rise or over-current. If your body presents too much resistance in the path there will be a rapid rise or "shock" which occurs or even burning.

    Remember the electric fence trick. Five kids hold hands in a line, the one at one end grabs an electric fence. The one who grabs the fence does not feel a shock, nor do those in the middle, it's the poor little kid on the other end that doesn't know what's being planned for him that gets whacked.

    ...

    Shortest path to ground as previously mentioned is not a path determination for lightning or arcing. Watch some slow-mo videos of arc flash if you don't believe this.

    Actually death occurs with less than a tenth of an amp across the heart, no burns necessary.

    Trust me on the fence thing - every single person in that chain feels it.

    Glad you mentioned arc flashes, after posting I realized I should have mentioned the lightning bolt itself - perfect example that it follow the path of least resistance and not the shortest distance. If it followed the shortest distance lightning bolts would be perfectly straight from the clouds to the ground (and cloud-to-cloud). People have been know to get zapped by lightning 5 miles away from a storm.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    The question was about single point ground functions and why. Your post makes no sense by completely ignoring Jessica's question, the context, and purposes of earthing.

    An electrically shortest path is not "path of least resistance". Read what BB posted. Path of least "impedance" (radio frequencies) is important. Involves other factors including and not limited to a conversion of gas to plasma. Other factors were irrelevant to Jessica's question.

    A shortest electrical path is not five miles across sky. Shortest path is down to a tree. Then through earth. That example demonstrates an answer to Jessica's question. And why superior surge protection best begins when footing are poured.

    Jessica's question was about single point ground. Where does your post answer questions by Jessica or mike90045? Whether the electrician keeps one hand in his back pocket (a good practice) or not is irrelevant.

    You were the one that posted that information, which was not related to single-point grounds or Jessica's question. I was just correcting your misinformation. And if you really want to go down this path, Jessica's question was not related to the OP's question. ;)

    Here in your response you are still confusing "shortest" with "the path that electricity takes, which is never the shortest (even in man-made conductors)". Even in plasma, which is just another conductor like air/gas, water/liquid, the earth/solid, and anything with multiple states of matter like your arm. Even in plasma it does not follow the shortest path - take a look at a plasma ball and let me know what you see... looks a lot like lightning. Not straight.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Whole house surge suppressors

    everybody should just calm down a bit. this is a very involved subject matter and the op should go with as much as he can and to a single point ground. now understand here that a single point ground does not necessarily mean a single ground rod as long as all rods are bonded together. it just makes it a larger single point ground and is a better ground.

    as to somebody or even a horse standing near a lightning strike and falling down dead does not mean the lightning hit them as emp levels near lightning can be lethal in and of itself.

    do know that concrete, dirt, and rocks are not good grounds or conductors of electricity for if they were we would not be striving for such a large contact area with them. what often makes them conduct is the water and metal content in them and this is still a high resistance so to overcome it a large contact area is needed. in fact in at least 99% of all cases an 8ft copper ground rod is really insufficient for a good ground point, but we strive for a good reasonable compromise.

    also note that satellite dishes have to be grounded too and to that single point ground.

    as to mike's example of the multiple buildings, i feel it is a great question. we could even include each and every power pole in this question too. ideally, they should all have a single point ground of very low ohms resistance bonded together, but this becomes nearly impossible to achieve over large distances. if 2 buildings, and even a pole, are somewhat close together i would bond all of the ground rods together underground. this helps to prevent differential voltage potentials from developing between them. with greater distances one might still see voltage potentials develop, but hopefully the resistance in the ground itself will dissipate large potentials.
  • Peter_V
    Peter_V Solar Expert Posts: 226 ✭✭✭
    Re: Whole house surge suppressors

    Would anyone mind if we get back to my original question?

    My question was about the whole house protector.
    Does anyone have an opinion on the Leviton 51110-1 SPD:
    http://www.amazon.com/gp/product/B002VJKAZS

    Will this be adequate protection or should I use a different brand/model?


    FWIW I'm quite familiar with grounding, as well as being a licensed amateur radio operator I've done a lot of work with tactical satellite terminals and other communications equipment.
    The ground on my house is as good as I can get it in our dry sandy soil, I have a 10 ft ground rod, the UFER in the house and about 70 feet of horizontal 8ga copper buried 2ft down, plus 25 feet coiled up in the footer for one of my trackers.
    All tied together at one point that is about 3-4 feet from the main panel, the whole house protector will be mounted next to the main panel.
  • thehardway
    thehardway Solar Expert Posts: 56 ✭✭✭✭
    Re: Whole house surge suppressors
    BB. wrote: »
    Lighting has significant radio frequency energy content... So you have to look at the "impedance" and not simple resistance. Becomes a much different beast than DC / low frequency resistance calculation.


    -Bill
    Are you saying lightning is an AC power event?



    As a disclaimer first let me say that no one understands the lightning process entirely. That said we do know a few things about it from studies (fulminology) and high speed video capture. We just aren't sure about the whole cause and effect relationship or what comes first as it is too big a picture to study at full scale.

    Here is a very impressive and revealing high speed capture of a lightning strike.

    http://www.youtube.com/watch?v=-bvmEYxEYiA&feature=related

    The first flashes of light you see are the setting up of the "stepped leader".

    This sets up an "ionized channel" and as it approaches the ground a "positive streamer" transcends upward and connects to it. This results in a "return stroke" which is the most illuminating and concentrated part of the strike. Once the channel is formed there are usually several pulses which take place in the channel. Notice how long the return stroke seems to remain, this is actually several upward and downward strokes within the channel.

    Lightning can be either a negative or positively discharge. Positive discharge lightning is typically the most damaging.

    Lightning can emit upwards from a fixed point as well as downward from the atmosphere. Notice the upward movement in the video from several fixed tower locations. Also note how lightning does tend to strike in the same location more than once in this video.

    Lightning is neither a true DC circuit nor is it a true AC circuit. It most resembles a DC pulse discharge followed by a return DC pulse discharge. This might be referred to as a single cycle AC event but that is a bit of a stretch. Neither the amplitude of the pulses nor frequency of the pulses are seldom equal.

    This may resemble a diminishing wave form but it is not a true AC current caused by pole reversal.

    The radio frequency (Xray and gamma ray) associated with lightning it is not likely part of the actual discharge but most likely the result of the excitement of the atmosphere around it either during or prior to it depending on the theory of development you subscribe to.

    Bill,

    As such I am not sure I understand your reference to impedance as impedance deals with AC circuits exclusively. Are you referring to the inductive and magnetic currents set up in the grid by a electrostatic event or are you referring to man generated current and not lightning? Can you explain?

    The one constant in all of this is that nature is always seeking to equalize potential or reach balance. This tendency to equalize potential weather it be radioactivity of isotopes (nuclear), High pressure/low pressure gradients in weather (Wind), ESD (lightning) thermal adsorption and absorption Solar thermal and geothermal), tidal flow, or hydraulic pressure (Hydro), is the basis for renewable energy. Any time you can capture and harness a naturally occurring imbalance you have potential energy. It is useable to perform work until it is back in balance or zero potential.

    This is the theory behind single point grounds. Zero potential means zero energy to destroy electronic circuits. Keep it balanced.

    Driving multiple grounds that are disconnected and have different potentials create a likelihood that an uncontrolled discharge can and will take place due to imbalance. This goes against nature.

    Hope this helps answer the questions. I agree even a small current in the body can kill a person but statistics say it is the heating portion of electrocution that actually causes more fatality.

    Good discussion. You won't find this from the salesperson when you go to buy a SPD at your local big box store.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Whole house surge suppressors

    Basically, lightning is an impulse event. The sharp leading edge contains high frequency rf energy. These can be represented by a series of different frequency sine waves. Aka the

    http://en.wikipedia.org/wiki/Fourier_series

    So, I am not talking about the direction of current flow, but the frequency content of the event.

    I can't look at the moment, but if I recall correctly, the maximum frequency with significant energy content is around 7 khz or so.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Sparkletron
    Sparkletron Solar Expert Posts: 71 ✭✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    The LED can only indicate a type of failure that means the protector was ineffective - grossly undersized.

    Unless you're talking about a specific product, how can you say what the LED indicates? On mine, the LED indicates full protection is present. The indicator light is extinguished when full protection is no longer present. It does not indicate a "type of failure".
    westom wrote: »
    Yes, the protector is good for a limited number of transients. So it should still be effective a decade later.

    Huh? Whether it should be effective a decade later, or a day later, depends entirely on the number and nature of transients the SPD must deal with.
  • westom
    westom Solar Expert Posts: 28 ✭✭
    Re: Whole house surge suppressors
    Unless you're talking about a specific product, how can you say what the LED indicates?
    Because the protector selling for $7 in a grocery store is the same protector circuit that Monster sells for $150.

    The LED does not report all failures. It only reports a catastrophic type of failure that must not exist (because the protector was grossly undersized). Normal (acceptable) protector (MOV) failures are not reported by those lights. But when hyping a mythical protector to the naive, then hearsay says that light reports all failures.

    The remove the protector circuits from this protector. Lights say the protector is still good. Learn what those lights are really reporting rather than the folklore:
    http://www.zerosurge.com/HTML/movs.html

    Or learn hoe MOVs work. Catastrophic (unacceptable) failure mode is when MOVs fail or vaporize. MOV manufacturers are quite blunt about that. It is the completely unacceptable failure. But if they grossly undersize a protector, then the failure gets the most naive consumers to recommend it. "My computer sacrificed itself to save my computer." Nonsense. The computer protected itself. The protector disconnected as fast as possible to avoid a house fire.

    Peter V - as a ham your understand why the connection from that Leviton to earth must be short, no sharp wire bends, not inside metallic conduit, etc. No protector does the protection. Your superior earth ground (ie Ufer ground) determines protection. A protector is only as effective as its earth ground.

    The important parameter for the Leviton is its current rating. It must be at least 50,000 amps to earth direct lightning strikes (ie 20,000 amps). And it must make that short connection to what defines all protection ... single point earth ground.

    A protector is only a connecting device. It must connect all surges harmlessly to earth - including lightning. Either the surge obtains earth via a harmless path via the protector. Or you have ineffective protection. The earth ground and connection determine how good that protector is for one surge. 50,000+ amps means the protector keeps doing protection for many surges.

    You might learn more from so many hams who actually do this stuff. Who are not so easily manipulated by retail myths. See "Grounding and lightning" in QRZ Forums starting 21 Dec 2010 at
    http://forums.qrz.com/showthread.php?t=277209
    > Everyone pretty much universally agrees grounding, and particularly bonding, is the
    > bulk of protection.

    > ... lightning is a radio frequency phenomina. Simply "bonding" things together with
    > length of conductor that has reactance defeats the whole purpose of bonding.

    > I'm pretty clear in saying the IMPEDANCE of the bonding has to be low.

    > I'd never rely on the ground pin on an AC cord for lightning protection. If
    > lightning gets that far, the surge passes through the equipment, and it is toast. A
    > common ground window for the electrical service, control cables and coax leads
    > before they enter the house will prevent a large potential difference building up
    > between the antenna system and power service.

    Either one is discussing protection always in terms of earthing. And where energy dissipates. Or one is reciting myths that advertising tells them to believe. Some are doing the latter.

    Single point earth ground is protection. Leviton is simply one protector that does effective protection when it connects short to earth. Protection is always about earth. A protector is only as effective as its earth ground. Ufer ground can be so effecitve IF every wire in every incoming cable connects to it before entering. Levition protector is one effective solution.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Whole house surge suppressors

    whether a byproduct of a strike or not, the energy is originally from the lightning. this is true of the thunder and all frequencies produced. it is ac energy, or pulsed dc depending on how you look at it, and is quite strong throughout the spectrum and gradually weakens as it goes up in frequency. impedance does apply even to a pulsed dc waveform. the only difference between ac and pulsed dc is the reference point.

    peter,
    i did go to your subject matter and i encouraged you to go ahead with something. i can't vouch for that particular one, but there are many of them out there. they usually take 1 of 2 forms. 1> mov which many here often see and 2> gas discharge tubes. gas tubes are short lived as it will work fast and at a low voltage, but once fired is kaputt. you may even want to check out midnight solar's future surge protector as seen here just about halfway down,
    http://www.midnightsolar.com/

    here's the manual on them,
    http://www.midnitesolar.com/pdfs/SPD_Installation_manual_3%20_2_.pdf

    it has some very large movs in it compared to other protectors and the blue led is kinda neat too. i believe there are 2 leds in the protector, one for each leg of the ac. they are bigger in size than the delta surge protectors so if room is an issue you may want to be sure they'll fit first.

    edit to add:
    the term protector may be overstating its function, for the record. they can increase the likelyhood of a survival, but are no guarantee. in fact, i doubt any such protector will survive a direct strike to protect anything. something like a faraday cage might do better in such a case, but that's not as easily done and isn't readilly marketable for everybody. as i've said many times, there are no guarantees when it comes to lightning as it does whatever it wants to. we can try to persuade it to go elsewhere though.
  • Sparkletron
    Sparkletron Solar Expert Posts: 71 ✭✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    Because the protector selling for $7 in a grocery store is the same protector circuit that Monster sells for $150.

    The title of this thread is: Whole house surge suppressors. The OP is not interested in cheap power strips from the grocery store that use cheap varistors. The OP is asking about whole-house SPDs, which are simply not in the same class.

    I'm not familiar with Monster SPDs, but if you think that all SPDs are the same, work the same way, or even rely on MOVs, then you need to do some research. There are many ways to shunt current and the quality of the components can vary significantly. This also explains why some SPDs carry no warranty and some carry ten-year warranties.

    All SPDs require a proper NEC-compliant ground. No one is disputing this--least of all the companies that produce these devices.

    But your point seems to be that the quality of your SPG is ultimately all that matters, and that if it can't handle a direct lightning strike then it's useless. Yet the vast majority of transients don't involve direct lightning strikes or anywhere near that much power. Indeed, most transients come from the power company or from inside your own home when you turn on/off washing machines, dryers, ceiling fans, etc. Component failure tends to involve cumulative damage over time. A whole-house SPD can certainly help in this regard. It can also help with nearby lightning strikes that induce current. Yes at some point it won't matter; given enough power your entire panel will vaporize. But the exception does not prove the rule, and a whole-house SPD is a good investment.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Whole house surge suppressors
    niel wrote: »
    as i've said many times, there are no guarantees when it comes to lightning as it does whatever it wants to. we can try to persuade it to go elsewhere though.

    This is the truth.

    Furthermore, the surge protectors are not designed to be lightning protection. Marketing hype that alludes to them as such is misleading at best. People get a false sense of security when they have one of these installed because they've been lead to believe it will protect them against anything that happens.

    That is impossible.

    Take it from someone who lives in "lightning strike city"; the best you can hope for is that any such device will reduce the likelihood of catastrophic failure due to transient Voltage spikes. And then only if properly installed.

    I see no point in belaboring this thread any longer. It's gotten quite off track and in many posts has meandered down wandering paths that are confusing and unhelpful to to OP and/or anyone else looking for helpful, practical information of protecting against Voltage spikes whether line sourced or lightning sourced.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Whole house surge suppressors
    westom wrote: »
    Because the protector selling for $7 in a grocery store is the same protector circuit that Monster sells for $150.
    Is that the same Monster as Monster audio cables? I wouldn't know spit about their surge protectors, but if it's the same Monster, they are major snake oil salesmen in the audio world, plus their business practices are atrocious. In addition to making all sorts of unsubstantiated and unprovable claims about their cables, they file nuisance lawsuits against anyone who uses the word "monster" in any commercial enterprise, irrespective of context.