Learn what an effective SPD does? This was first demonstrated by Franklin in 1752.

Lightning (and other surges) seeks earth ground. A best connection to earth is via a wooden church steeple. Because wood is a better electrical conductor than air. Unfortunately, wood is a poor conductor. So a 20,000 amp lightning strike would create a high voltage. 20,000 amps times a high voltage is high energy. Church steeple damaged.

Franklin connected lightning to earth via a better conductor - often called a lightning rod. That conductor is a better conductor. So a 20,000 amp lightning strike creates a near zero voltage. 20,000 amps times a near zero voltage is near zero energy. No damage.

That is protection of a structure. We do same to protect appliances.

Lightning seeks earth ground. A best connection to earth is via appliances. Unfortunately appliances are poor conductors. So a massive current would create a high voltage inside the appliance. That high current times a resulting high voltage is high energy. Appliance damaged.

For over 100 years, informed consumers connected lightning to earth via a better conductor. Usually a direct hardwire connection. Otherwise a next best solution is implements: a 'whole house' protector. Then 20,000 amps connected low impedance (ie 'less than 3 meters') to earth creates a near zero voltage. The resulting near zero voltage means no energy dissipates destructively in appliances. No appliance damaged.

A protector adjacent to the appliance does not do this. The protector at the service entrance must be sized to connect even direct lightning strikes to earth. And not fail. So a minimal 'whole house' protector is 50,000 amps. If a surge damaged that protector, then a 100,000 amp protector is needed in that venue.

Described is what effective protectors work, why they work, and relevant numbers such as 50,000 amps. Because any protector that fails did not provide effective protection. Protectors must not fail even after many direct lightning strikes.

What should also be obvious is what is more important than a protector. Protection is defined by the quality and connection to earth ground. Both for structure protection and for appliance protection. Most of your attention should focus on THE most important component in every protection 'system': earth ground. Since that is always where hundreds of thousands of joules harmlessly dissipate.

This post has been edited by westom: Jun 1 2014, 05:22 AM

Apparently important numbers were ignored. That ground in a wall receptacle is not earth ground. Codes require a safety ground. Electrical characteristics such as 'less than 3 meters', no sharp wire bends, no splices, and ground wire separated from other non-grounding wires are critically important. Please grasp important references to low impedance to appreciate a difference between 'safety' ground and 'earth' ground.

Lightning is best connected to earth via a direct hardwire connection. A next best solution implements the same low impedance, earth ground connection via a 'whole house' protector. Then 20,000 amps connects low impedance (ie 'less than 3 meters') to earth; creates a near zero voltage. A resulting near zero voltage means no energy dissipates destructively in appliances. No appliance damaged.

Protectors adjacent to appliances cannot earth that energy. Too close to appliances and too far from earth ground electrodes. These devices must somehow block or absorb energy. This different device, also called a surge protector, does not claim to protect from destructive surges. Instead, it only claims to protect from surges typically so small as to be made irrelevant by protection already inside appliances.

Sometimes a surge too tiny to harm an appliance will destroy a grossly undersized and adjacent protector. A failed protector did not do protection. The appliance protected itself.

Concepts such as wire bends and wire length can subvert an earth ground connection. For example, connect a 200 watt transmitter to a long wire antenna. Touch one part of that long wire to feel near zero volts. Touch another part to be shocked by over 100 volts. Why two voltages on the same wire? These electrical characteristics explain why a wall receptacle's safety ground is not earth ground.

Effective protector must be located adjacent (ie 'less than 3 meters') to a single point earth ground. Last four words also have electrical significance. A protector too far from single point earth ground (ie connected to a wall receptacle) is not earthed. And does not even claim to do what an effective 'whole house' protector does.

Rather than ignore relevant numbers, appreciate these electrical concepts even defined in IEEE standards. What many mistake as an earth ground is really only a safety ground. This difference explains why best protectors are distant from appliances (ie up to 50 meters) and as close to earth ground as practicable. Please do not ignore the expression 'low impedance'. Protectors without that 'low impedance' connection do not claim to protect appliances from destructive surges. Ignoring that voltage discuss implies you did not understand an important concept: impedance.

This post has been edited by westom: Jun 1 2014, 10:08 PM

A protector must not fail. So what will be a typically largest surge? Lightning is typically 20,000 amps. So a minimal SPD should be rated at least 50,000 amps.

SPDs have an indicator light that only reports one type of failure. If its indicator light reports any failure, then the SPD was grossly undersized. Then a 100,000 amp protector is probably necessary.

SPD is only one part of a 'system'. SPD must be sized to not fail over many decades. The 'system's effectiveness during each surge is defined by the other and more important component - earth ground. 'System' effectiveness for each surge is defined by the quality of and connecton to single point earth ground.

Protectors are simple science. Earthing is an 'srt'.

So how often is your town without phone service for four days after each storm? A typical bulding may suffer a major surge every seven years. But the telco's computer is connected all over town. Thefore it suffers about 100 surges per storm. And without damage. Because protection from direct lightning strikes has been that routine for that long.

If protection from direct strikes could not exist, then telephone operators would remove headsets and leave the room with each storm. Reality. Even 100 years ago, that was unnecessary. Because protection from direct strikes was that well understood that long ago.

Protection uses a proven concept similar to a Faraday cage. But a Faraday cage is compromised if even one wire in any cable does not first connect to what performs a Faraday cage effect - single point earth ground. That is what a protector does. Protection is compromised if a protector does not make that low impedance (ie 'less than 3 meters') connection to single point earth ground.

A 'more sensitive' equipment is virtually every household appliance. That includes the dishwasher, air conditioner, dimmer switches, CFL bulbs, and clocks. Most every appliance now contains electronics. And all appliances are now as or more robust than that appliance was 40 years ago. Homeowners are only just learning about what was standard 50 years ago in facilities that could never have damage.


This post has been edited by westom: Jun 2 2014, 07:25 PM

Of course not - as I said. KL must have long used a 'whole house' solution. Their switching computer is threatened by about 100 surges with each storm - without damage. Because surge protection routinely makes direct lightning strikes irrelevant.

If you read something the first time and understand it, then it did not introduce anything new. If a concept is this new, then it should be reread at least three times. You misunderstand (misread) an example of direct lightning strikes without damage.

I never said KL suffered 4 days of downtime. Please read what was posted. I said KL never experiences 4 days of downtime because protection from direct lightning strikes is routine. So routine that damage is traceable to a human mistake.

This post has been edited by westom: Jun 2 2014, 07:37 PM

IEEE is a source of what I have summarized. For example, IEEE Std 142 is entitled 'Static and Lightning Protection Grounding:
Standard 1100 says:
Summarized here are the principles that all industry professionals discuss for protection. A protector is only as effective as its earth ground.

Another IEEE Standard says

IEEE Standard 80 says: What is that secondary arrester? The 'whole house' protector. Secondary protection is located at the service entrance. A primary protection layer is installed by the utility.

One can criticize. Or one can first comprehend their technical sources. IEEE and I say same. Another forget to read what the IEEE says.

Correct. So why the confusion? This was explained repeatedly because it is new and therefore difficult to grasp.

Or maybe another fundamental fact, posted previously, was misunderstood. Electricity is never same at both ends of a wire. Earth ground and safety ground are electrically different. I don't understand why this fundamental fact was not read. Was that long wire antenna example unread?

Receptacle safety ground is not earth ground. Why is that confusing?

A ballpark three meter rule comes from basic circuit theory. One protector is best because it has no earth ground connection. Instead, that protector mounts ON earth ground. Zero meters to earth means better protection.

Correct. Primary protection is provided by the utility. A picture demonstates what does that protection:
http://www.tvtower.com/fpl.html

Secondary protection is not a lightning arrestor (lightning rod or protector). Those are only connecting devices. Each layer of protection is defined by what absorbs hundreds of thousands of joules. A protector only connects to that other 'system' component: earth ground. Earth ground (not an arrestor) is the protection. Due to advertising myths and hearsay, this concept is extremely hard to grasp.

A protector is only as effective as its earth ground. Same is also true for lightning rods. Lightning rod is for protection of a structure. 'Whole house' protector is for protection of appliances. In every case and in every layer of protection: the only component that must always exist and that does the protection is earth ground.

This post has been edited by westom: Jun 3 2014, 12:48 PM

No debate exists. Provided was the science. You openly deny using wild speculation, hearsay, and by ignoring 100 years of proven science. If it was a debate, then your beliefs are supported by facts and numbers. You have yet to post even one manufacturer specification number that defines effective protection. Honesty also provides facts with numbers. Lies and myths are quickly identified by subjective (qualitative) denials.

Look. I did this stuff for decades. And you clearly did not. Direct lightning strikes without damage. Others are warning about the naive who make recommendations only because advertising taught them. Provided are basic concepts and numbers that define protection. You tire only because you cannot dispute over 100 years of well proven science. And refuse to admit hearsay easily manipulated you. So now you would attack the messenger rather than admit to being a victim.

IEEE recommend tiny additional protectors only with the 'whole house' solution. IEEE and other professionals are bluntly clear about that. One brochure even shows a protector earthing a surge 8000 volts destructively through an adjacent TV. Becase the 'whole house' solution was not implemented and earthed. Please stop reading IEEE material selectively. IEEE says what works by also saying where hundreds of thousands of joules harmelessly dissipate.

Why, in every reply, do you ignore that reality? It is not a debate. It is science exposing parables and fables. If you know this stuff, then quote the specific electrical concepts and numbers from your own citations. You cannot. An honest reply quotes the relevant point. But you really do not understand what is relevant. You you throw mud on the wall hoping that something might stick. Please stop denying over 100 years of well proven science.

A protector is only a connecting device to what does protection. What does protection is what harmlessly absorbs hundreds of thousands of joules. That simple science could not be easier. Only solution in facilities that cannot have damage has always been a "low impedance" connection to earth ground. For over 100 years, the proven solution has always said where hundreds of thousands of joules harmlessly dissipate. Rather than vent emotions, why not answer the fundamental question? Where do hundreds of thousands of joules harmlessly dissipate?

There is no debate. The question, that you refuse to answer, is asked repeatedly. Where does that energy dissipate?

A plug-in protector has a purpose. It may provide an additional 0.2% protection. But only when used in conjunction with the 'whole house' solution. It does what its spec numbers says it will do. It does not claim and cannot protect from typically destructive surges that occur maybe once every seven years. Those are realities provided with numbers.

Protection is always about earth ground - where hundreds of thousands of joules are harmlessly absorbed. Each protection layer is defined by what harmlessly absorbs energy - earth ground. Some protection systems have no protectors. But every protection layer always has the one item that defines protection - earth ground. Always. Advertising will not discuss earth ground. No profit in it. Over 100 years of science and experience is why every facility that cannot have damage upgrades and inspects THE most important component in the protection system - earth ground. They inspect, learn of, and fix potential problems. And do not tire by remaining attached to lies and myths.

Where do hundreds of thousands of joules harmlessly dissipate? A protector is only as effective as its earth ground. Each protection layer is only defined by what absorbs the energy - earth ground. Reality does not change because you remain in denial.

This post has been edited by westom: Jun 3 2014, 10:05 PM

Concepts such as impedance are taught to first semester students. If impedance is unknown, then you have no business denying what has been well proven for over 100 years. Why impedance is significant was discussed repeatedly.

Why grounds are different was explained many times; using multiple reasons. Impedance is one. Since this is new, then do what was (should have been) taught in school. Something this new requires multiple rereads. Go back and read those many paragraphs that apparently you ignored. Then post what you understand. Followed by where you become confused. It was explained repeatedly. But you have to do the work - first read it.

Electricity is always different at both ends of every wire. How that difference is relevant was explained multiple times - sometimes with numbers. Electrical concepts make obvious that various grounds are electrically different. A repeatedly posted number (you could not miss it) even defines this: 'less than 3 meters'.

This post has been edited by westom: Jun 4 2014, 12:46 PM

Helpful would be to read what was posted rather than read what your emotions want to see. Clearly SPDs were repeatedly recommended. But only effective ones from more responsible manufacturers.

How do you write when you cannot read?

Please read what is posted. Nobody said tnb installed a protector. Again you read only what you want to believe. An EE need not reread those paragraphs. Since concepts were taught to every first year EE. You do not even understand ground differences. This layman simple concept identifies which protectors protect from destructive surges.

Obvious was what tnb installed. With insufficient EE knowledge, you even confused a protector and protection. And did not even know what impedance is. Any first year EE would know that.

You were asked to reread what you ignored. Define what you understood. And then ask about concepts that confused you. You refused to even do that. It would expose no EE training. So you attack the messenger. Any EE would know why various grounds are electrically different. Would know why different voltages can exist on the same wire. And would immediately grasp why a 'whole house' solution is routine in every structure that cannot have damage. Instead, your disparaging remarks now become cheapshots.

A properly earthed 'whole house' solution is required with or without adjacent protectors. Since protection is always about where hundreds of thousands of joules harmlessly dissipate. Always. A protector is only as effective as its earth ground. Fundamental to any reader who asked for effective protection.

Homeowners should also inspect their AC utility installed protection (as described in an earlier post). Do not let naysayers confuse you with cheapshot attacks. And claims devoid of basic EE knowledge (ie no numbers). A protector connected within meters to single point earth ground is the only solution found in every structure that cannot have damage. This best solution is also a least expensive solution.

That summary does not say what to do. Only says effective protection is about something completely different. Provides nothing for a consumer to act upon. Therefore may remain deceptive.

For example: less than 5 ohms may be insufficient. A 'less than 3 meter' rule is not about low resistance. Protection is about low impedance. That may appear complex, But is so layman simple as to be understood even 100 years ago. Is it too complex because no magic box was recommended? Consumers who all but want to be scammed do not want to know why. They want a magic box recommendation. No magic box will disuss impedance. Meanwhile impedance and resistance are somehow confused. An example that what really matters still remains so new to others. But those reasons why remain necessary.

Some of the layman simple rules. A properly sized protector should be at least 50,000 amps. Every incoming wire from every utility cable must connect low impedance via a protector or directly via a hardwire. That ground must be a single point earth ground. All four words have significance. These rules become simpler once 'reasons why' expose other popular fables. Since effective protection is always about where hudnreds of thousands of joules are harmlessly absorbed. Another simple rule that defines protection.

Another concept is summarized. Size a protector so as to remain functional after many surges. Install earth ground to make the 'system' effective during each surge. Protector is selected for its life expectancy. Earthing defines protection during each surge.

Any layman can read specification numbers. A transient that is hundreds or thousand joules is routinely made irrelevant by protection already inside all appliances. How many joules does that "indoor - surge protection device" claim to 'block' or 'absorb'? A transient that will not damage an appliance can also destroy that indoor device. Sometimes even create fires. One need only read that spec number.

Why would anyone spend so much money on such as tiny (near zero joule) device? Hearsay, advertising, wild speculation, and feelings somehow justify a recommendation.

Effective protection always answers this question. Where do hundreds of thousands of joules harmlessly dissipate? Only informed consumers read many paragraphs to learn what works and why. Any recommendation (for anything) that does not say why and is not tempered by numbers is often a scam.

That is about protection of appliances inside a structure. A lightning strike many blocks down the street is a direct strike incoming to all household appliances. Only a properly earthed 'whole house' solution protects from typically destructive transients.

Protection of the structure means something completely different. "lightning conductor at rooftop and full earthing system". Properly earthed lightning rods do nothing to protect appliances. And properly earthed 'whole house' protection does nothing to protect the structure.

What do both always required to be effective? Earth ground. Earth ground makes a lightning rod effective. Earth ground means a 'whole house' protector is effective. Ben Franklin demonstrated this over 250 years ago. And yet so many still do not get it. Earth ground is where hundreds of thousands of joules harmlessly dissipate. A protector or a lightning rod is only as effective as its earth ground.

No "indoor - surge protection device" has an earth ground connection, will not even discuss it, and does not claim to effectively protect any appliance. But it sure does have an obscene profit margin that pays for a massive advertising program. So it must be better - spec numbers be damned. They said it is better; so it must be better.

This post has been edited by westom: Apr 5 2019, 05:08 AM

Anyone who understands what Ben Franklin did can understand what works. The electric current goes from a cloud (ie 3 kilometers up) to earth borne charges (ie 4 kilometers distant). Why is that complicated? Either that electric current makes that 7 kilometer connection inside a building. Or it makes the same connection outside via that earth ground rod. It was always that layman simple - as first explained in primary school science.

Now, how good is that connection. If lightning wants to use the building, then a lightning rod connects it to earth on a path that remains outside the structure. No damage to a structure.

If lightning wants to use appliances inside a building, then a 'whole house' protector connects it to earth on a path that remains outside the structure. No damage to appliances. Why is that so hard?

If a protector's earth ground is not single point earth ground, then one has invited lightning to be inside - destructively via appliances. Multiple earth grounds (ie plung another grounding rod at the garden side) makes appliance damage likely. A surge, incoming on AC utility wires will use the other ground rod to connect to distant earthborne charges. That connection will be destructively through appliances.

No protector does protection. Without a good grounding in earth, the device will not work; will not be effective. Because no protector does protection. This is very hard for people educated by advertising. A plug-in protector does not have that low impedance (ie less than 3 meter) connection to earth. So it does significantly less or no effective protection. And can even make appliance damage easier. A protector must connect low impedance (ie hardwire has no sharp bends) to single point earth ground. To the one and only earth ground electrode that all incoming utility cables connect to.

If any incoming utility cable does not first connect to that same earth ground (ie directly or via a protector), then appliance protection is compromised.

Lightning rods never make lightning strikes more likely. That has always been an urban myth promoted by scammers who promote useless products such as ESE devices. Lightning rods are always implemented everywhere that lightning damage cannot harm a building. That direct strike is going to happen with or without that lightning rod. A building owner decides to let it strike the building or to connect to earth harmlessly via a lightning rod. Only ESE scams and other outright lies deny what lightning rods have done successfully for over 250 years. Connect the inevitable direct lightning strike to earthborne charges on a path that is not destructive.

If any of this is complex, then 1) it is new, and 2) one has not yet read it at least three times. Even a genius never understand something new until after, at least, three rereads. It may take more rereads if one was educated by lies from plug-in protectors, ESE manufacturers, advertising, wild speculation, or hearsay.

Why do we teach what Ben Franklin demonstrated in primary school science? Concepts of lightning protection have alwaus been that simple. However, if educated by lies (ie plug-in protectors), then comprehension is harder. Unlearning those lies (from plug-in protectors or ESE manufacturers) makes learning challenging.

Protection is always about the path a current will take from cloud to earthborne charges. Only a human makes that decision - to either have damage or to connect that current on a path that causes no damage. We know this for both lightning rods and for protectors. Both are only as effective as its earth ground electrode. Facilities that cannot have damage routinely earth hardwire connections or protectors on a low impedance (ie hardwire must not be inside metallic conduit) path to single point earth ground. Anything that does not connect that transient low impedance (ie less than 3 meters) to single point earth ground will never answer the relevant question. Where do hundreds of thousands of joules harmlessly dissipate? It is only hard when one has been scammed by advertising and myths that promote scams (ie plug-in protectors).

Wall 'power point' safety ground is not, cannot be, and never will be earth ground. Difficult for many to grasp. That wall receptacle safety ground is not and will never be an earth ground. Better is even more electrodes at the same common point. Protectors must have a low impedance (ie less than 3 meter) connection to single point earth ground. Otherwise a protector does nothing useful.

How far is the connection from each utility cable to that electrode - either by hardwire or via a protector. If more than 3 meters, then it does human protection and compromises appliance protection.

Does every wire inside every incoming cable connect to that one earth ground rod? If not, then appliance protection has been compromised. An AC utility demonstrates these concepts in good, bad, and ugly (preferred, wrong, and right) solutions at:
https://www.duke-energy.com/energy-educatio...ality/tech-tips
then select Tech Tip 8.

One electrode is usually sufficient. But that is dependent on the soil and other geological features. For example, sand is a poor conductor. So more electrodes are necessary.

Repeated because it is that critical. Each connection to that electrode must be low impedance. Ie less than 3 meters, no splices, not inside metallic conduit, no sharp bends, separated from other non-grounding conductors. Inspection goes a long way into learning what is sufficient.

This post has been edited by westom: Apr 5 2019, 09:07 PM

Follow that wire from DB to electrode. For example, if it goes up over a foundation and down to an earthing electrode, then protection is compromised. It is unnecessary too long. It has sharp bends over the foundation. And it is best routed away from other non-grounding wires.

Better would also put another electrode maybe somewhere before the original one. Since those are cheap and it would expand and make more conductive that earth ground.

Whether that is necessary is a function of neighborhood history. For example, a transient typically happens once every seven years. Ten or twenty years of neighborhood history would better quantify risk.

Even the ELCB must be protected. Better is to connect an incoming transient to earth so that it does not go through the ELCB. An electrician can better determine what local codes also require.

A FL house suffered repeat lightning strikes to one wall. So they installed lightning rods. And suffered another strike to that wall.

Lightning is a connection from cloud to distant earthborne charges. That wall contained bathroom (plumbing) pipes that connected to deeper limestone. Lightning rods were connected to 2.4 meter electrodes only in sand. An inferior connection.

Solution. Longer electrodes were driven into that deeper limestone. That lightning rod made a better connection to those distant earthborne charges. That bathroom wall suffered no more strikes.


For protection of appliances or for protection of a structure. It is always defined and about the connection to and quality of earth ground.

BTW, many only use specuation to assume lightning rods with sharp points are better. Research was clear. Blunt rods are more effective than pointed ones.

Which ground? That was a major point. Motherboard ground, floating ground, mains ground, receptacle safety ground, chassis ground, virtual ground, analog ground, or static electric ground beneath shoes? All are different.

A relevant ground has at least two words - earth ground. All incoming wires must make a low impedance (ie less than 3 meter) connection to that one and only ground. Why is that hard? (A question that expects an answer because I just do not get it.) A homeowner is responsible for inspecting and maintaining that ground. Just another reason why that ground should not be complex ... if you are the homeowner.

Apparently this is all new. So it will not begin to make sense without at least three rereads. It really is quite simple. How does that current connect to earthborne charges maybe 4 kilometers away without going through any appliance or the structure?

Earth ground would be low ohm resistance. The connection to earth ground must be low ohm impedance. Electrician would not have any equipment to measure impedance. And most probablly do not know what impedance is.

But we make it simple. A low impedance connection is short (ie less than 3 meters), has no sharp bends, is not inside metallic conduit, and has no splices.

Generally, many electrician cannot measure earth ground resistance. So most simply install two electrodes. One is more than sufficient to protect human life. More (sufficiently spaced apart) are necessary to protect appliances.

Rather than measure ground resistance, a decision for earth ground may be determined by geology. Sandy soil needs an enhanced ground. Earth of fine particles that stays moist (therefore is more electrically conductive) means one or two electrodes are probably sufficient.

This post has been edited by westom: Apr 9 2019, 10:58 AM