Are Surge Protectors bunk or beneficial?

[JerryLove]

OK. Show me one.

Here's a scenario. I'm sitting in my breakfast nook talking on my cordless phone. Lightning comes through the window and hits the antennae on my phone. What will save the phone (and preferably me as well).

Nothing protects equipment that has been directly struck (shy of a Faraday cage, but even that's a cheat in that it prevents direct strikes from happening).

If you want to deny reality, then distort what was posted. Meanwhile the post actually said:
"Your effective protector costs about $1 per protected appliance - so that even direct lightning strikes do not damage your dishwasher, furnace, dimmer switches, and other expensive electronics."
Read what was posted (reality) rather than entertain your emotions.

I'm still waiting. My phone is one of my expensive electronics. Why haven't you answered my question?

 

[chris357]

If you want to deny reality, then distort what was posted. Meanwhile the post actually said:
"Your effective protector costs about $1 per protected appliance - so that even direct lightning strikes do not damage your dishwasher, furnace, dimmer switches, and other expensive electronics."
Read what was posted (reality) rather than entertain your emotions.

Those scary pictures have been observed by most fire departments. Even a NC fire marshal defines the problem - reasons for fire.

However if your emotions need to label others liars, then don't forget to accuse Norma. She posted on 27 Dec 2008 in alt.fiftyplus entitled "The Power Outage":
"

I'm not saying you are a liar nor trying to misquote you. But i think you are taking things to personally and I know how this goes because i do it to sometimes.. (for example a thread on power cables where I got shredded) its ok I learned alot

but heres a reality, you are blaming the surge protector for a fire or for smoking when the cable guy damages the ground wire in a house?

that is a result from a different cause .. any appliance could have started smokiing afte that.. so we shoudl be targeting the ground wires not the surge protector? right?

in any instance you have to look at all the variables and not select just part of it (the part that suits your argument)


your argument is like saying peanuts are bad.. because people are allergic to them

well not everyone...

or stoves are bad because they start fires
they are supposed to, but if you leave it on unattentded it coudl be bad...

cars are bad because they kill people
only when driven by idiots ..

these are all true if thats what you want to show someone and all you want to look at, but the reality is that there are millions and millions of surge protectors out there and they are NOT burning houses down daily as you woudl have us believe.

is a whoe house protector better..

yes probably

is it cost effective

maybe

if more people knew about them would more people have them

probably

is anything only as good as the way that it was made and actually implemented

YES

 

[lsiberian]

I understand what Westom is saying.

We are essentially putting a bandaid on a major problem if we think a surge protector is sufficient for preventing problems.

The most important thing for any home or business is that it's electricity is properly grounded. Without proper grounding a surge protector is worthless because it will not be able to move out the bad current. He's saying as long as we have good grounding most appliances will ground themselves(not sure on this one). I can see the point in this situation.

I can agree everyone should make sure their home is properly grounded. This is an indisputably wise thing to do.

However my argument for a good surge protector is that with a good ground it can help lengthen the life of electronics. A light bulb would be an excellent demonstration of this. However the concern is the protector itself can ignite and cause fires. So their is a delicate balance between longer lasting light bulbs and a fire starting machine.

I conclude that these 3 points

1. Check to make sure your home is properly grounded
2. If you chose to use a power strip with surge protection keep a fire extinguisher handy and put in a fire safe location.
3. Be aware that electricity is dangerous when not handled properly and respected. So take seriously the steps to make your home safer.

For this discussion a direct lightning strike is considered one that hits your power line. Not one that hits you. Protection against that is another topic completely.

 

[JerryLove]

I understand what Westom is saying.

We are essentially putting a bandaid on a major problem if we think a surge protector is sufficient for preventing problems.

That may be a valid lesson from his post, but it hardly seems to be the crux of what he is saying.

He's gone out of his way to identify (specifically APC) surge suppressors as useless. Other than that rant, and a particularly disturbing interest in my parentage, I have trouble summing his point as he's made a lot of contrary claims.

The most important thing for any home or business is that it's electricity is properly grounded. Without proper grounding a surge protector is worthless because it will not be able to move out the bad current. He's saying as long as we have good grounding most appliances will ground themselves(not sure on this one). I can see the point in this situation.

There's truth there. The electricity needs a place to go, or the only useful protection is a circuit-breaker. Without a ground-path (and preferably a good one), there's not a lot that can be done.

It seems that the built-in ground on most appliances is built more around short-circuits (giving a short an easy path to ground) than it is about protecting from over-voltages. I'm sure not all equipment is the same in this regard: but I think most appliances are just more rugged that most people give them credit for. This is why we don't tend to put surge suppressors on stoves.

So yes, we need a good ground. If we want to so lightning arresting properly: we need a good surge arrestor (that opens the circuit on failure) where power comes in, and with an easy path to ground.

It seems prudent to put further suppression on the most vulnerable of gear. Not only for surges that might get through, but for those that might originate inside the houses electrical system itself.

On computer equipment, uninterruptable power is also a good idea. I think it is on electronics as well, though I admit I can't prove it as readily. Certainly undervoltages were admitted by even the most anti-ups-person (westom) of damaging electric motors, and those are in some AV gear.

In short: if you wouldn't put it on a dimmer switch, then you should be worried about power dips on it.

However my argument for a good surge protector is that with a good ground it can help lengthen the life of electronics. A light bulb would be an excellent demonstration of this. However the concern is the protector itself can ignite and cause fires. So their is a delicate balance between longer lasting light bulbs and a fire starting machine.

Put a surge arrestor on the house with a lower voltage tolerance than the suppressors inside. Also, make sure that there's a thermal breaker in your suppressor to prevent it from over-heating. Make sure it fails-open or it will not burn, but also stop protecting.

For this discussion a direct lightning strike is considered one that hits your power line. Not one that hits you. Protection against that is another topic completely.

Are you sure Westom will make that same distinction? He doesn't seem to want to admit that anything can pass his perfect ground.

Your best shot for a "hit my power box outside" strike is going to be a surge arrestor with a good ground outside.

 

[lsiberian]

That may be a valid lesson from his post, but it hardly seems to be the crux of what he is saying.

He's gone out of his way to identify (specifically APC) surge suppressors as useless. Other than that rant, and a particularly disturbing interest in my parentage, I have trouble summing his point as he's made a lot of contrary claims.

There's truth there. The electricity needs a place to go, or the only useful protection is a circuit-breaker. Without a ground-path (and preferably a good one), there's not a lot that can be done.

It seems that the built-in ground on most appliances is built more around short-circuits (giving a short an easy path to ground) than it is about protecting from over-voltages. I'm sure not all equipment is the same in this regard: but I think most appliances are just more rugged that most people give them credit for. This is why we don't tend to put surge suppressors on stoves.

So yes, we need a good ground. If we want to so lightning arresting properly: we need a good surge arrestor (that opens the circuit on failure) where power comes in, and with an easy path to ground.

It seems prudent to put further suppression on the most vulnerable of gear. Not only for surges that might get through, but for those that might originate inside the houses electrical system itself.

On computer equipment, uninterruptable power is also a good idea. I think it is on electronics as well, though I admit I can't prove it as readily. Certainly undervoltages were admitted by even the most anti-ups-person (westom) of damaging electric motors, and those are in some AV gear.

In short: if you wouldn't put it on a dimmer switch, then you should be worried about power dips on it.

Put a surge arrestor on the house with a lower voltage tolerance than the suppressors inside. Also, make sure that there's a thermal breaker in your suppressor to prevent it from over-heating. Make sure it fails-open or it will not burn, but also stop protecting.

Are you sure Westom will make that same distinction? He doesn't seem to want to admit that anything can pass his perfect ground.

Your best shot for a "hit my power box outside" strike is going to be a surge arrestor with a good ground outside.

Your best shot is to live in an area with underground power lines.

Remember engineers deal in statistics so the idea is to reduce the probability of issues the best you can. A truly direct strike will cause more problems than electrical ones.

 

[njedpx3]

My new surge protected environment

Your best shot is to live in an area with underground power lines.

Remember engineers deal in statistics so the idea is to reduce the probability of issues the best you can. A truly direct strike will cause more problems than electrical ones.

Westmon has told me that nothing is safe so I am downgrading everything.

My HT is going to be a nose whistle and snapping my fingers.

My computer is going to be an abacus, a big chief tablet and a number two pencil.

I am changing to beef jecky and can food.

My room will have no windows, 3 foot thick concrete and be isolated and have a 10ft ground cable with no kinks every several feet.

Then I think I will be truly surge protected

 

[Adam]

I am changing to beef jecky...

Snap into a Slim Jim!

 

[JerryLove]

One other thing:
Most lightning strikes will not hit the side of your house.
Most houses have grounding included in the circuit already.
For the most delicate of equipment, most surges should be controllable by a power-strip that simply grounds excess voltage back to the ground wire on the plug (which eventually traces back to the house ground).
Normally, these things will not catch on fire (though sadly, most fail-on, meaning they may stop working and you not know)

 

[westom]

Most houses have grounding included in the circuit already.
For the most delicate of equipment, most surges should be controllable by a power-strip that simply grounds excess voltage back to the ground wire on the plug (which eventually traces back to the house ground).

Demonstrated again is insufficient technical knowledge. How many times will you confuse safety ground with earth ground? Using your reasoning a lightning rod can be connected to motherboard ground - because all grounds are same.

What will a power strip do to delicate equipment? Earth a surge destructively through delicate equipment.

That power strip must either absorb hundreds of thousands of joules, or earth a surge destructively through the adjacent appliance, or fail catastrophically. Sometimes the catastrophic failure creates those scary pictures. It still does not provide protection. And the manufacturer still does not claim to provide effective protection. Why would one recommend the ineffective solution that also costs tens or 100 times more money? A mythical engineer would recommend mythical solutions.

Again, an important parameter is that short (ie 'less than 10 foot') connection to single point earth ground. No earth ground means no effective protection. Explains why JerryLove never provides APC numeric specs that claim protection. He cannot. Even APC will not claim what JerryLove posts.

The house can be 1950 vintage (no safety grounds on any receptacle). And still one 'whole house' protector provides effective protection for everything in the building. APC products used on two wire receptacles would violate safety. Just another reason why one 'whole house' protector is always the superior solution.

Why spend $25 or $150 per appliance for plug-in protectors that do not even claim to provide protection? Brainwashing? Better is to install the solution that costs about $1 per protected appliance. The effective solution has been standard for over 100 years. The effective solution even makes direct lightning strikes irrelevant. The effective solution can be installed even in buildings with only two wire receptacles. To be more effective, a protector is located farther from appliances and as close to earth as practicable.

The informed consumer wastes no money on the APC. Instead spends tens of times less money on effective protectors from responsible companies such as Intermatic, Leviton, Siemens, Square D, Keison, General Electric, Cutler-Hammer, etc. The informed consumer knows a protector is only as effective as its earth ground, does not fail due to surges, and diverts surges harmlessly into earth. The informed consumer knows a protector is only as effective as it earth ground. The informed consumer ignores recommendations from another who even lied about being an engineer. And who still cannot find even one manufacturer spec to support his myths.

 

[westom]

but heres a reality, you are blaming the surge protector for a fire or for smoking when the cable guy damages the ground wire in a house?

And still a protector must not spit sparks. Only ineffective protectors do that, in part, because it gets the naive to recommend more.

If you want all variables listed, well, the posts (that are already too long) must be significantly longer. These posts are already to long for the electrically naive (ie JerryLove). Bottom line, Norma's event and those scary pictures are too routine. Must never happen. How often does your furnace spit sparks and flames? Is that also acceptable at any time?

If the protector was effective, it does not fail catastrophically and does not create scary pictures. And is not located where fire risk is greatest - on a rug, behind some furniture, or on a desktop full of papers. Just another reason why plug-in protectors can be dangerous. You did not get it. No minimally acceptable protector can do what Norma saw and is too often seen by fire departments - ie that Boston apartment fire. However catastrophic failure does get the naive to assume, "My protector sacrificed itself to save my computer." A myth. But the event gets the naive to recommend it.

Yes, the 'whole house' protector is better for a long list of reasons - some posted earlier. The 'whole house' solution was standard even 100 years ago AND is the only solution found in facilities that can never suffer damage. Is it cost effective? Of course it is. Obviously so. Not even close to 'maybe'. Your telco wastes no money on what JerryLove, et al recommend. Everywhere in the world, telcos use properly earthed protectors that actually provide effective surge protection - that are overwhelmingly cost effective. But again, does the phrase 'tens or 100 times less money' sound familiar?

Why is Norma's 'spark spitting protector' is acceptable? Those scary pictures are not isolated events. What do you think happens when a grossly undersized protector must protect from a surge that is hundreds of thousands of joules? What do you think happens when the protector is optimized for profits? Scary pictures. A problem with protectors that do not even claim to provide surge protection.

But again, maybe you missed the point. The manufacturer does not even list protection in his numeric specifications. You call that acceptable? Why do munitions dumps and US Air Force facilities do not use that protector?

 

[westom]

Your best shot is to live in an area with underground power lines.

Underground or overhead makes little difference. Too many reasons why were already provided. A short application note from an industry professional demonstrates the concept. Both underground and overhead wires require the same protection:
http://www.erico.com/public/library/fep/technotes/tncr002.pdf

 

[JerryLove]

Underground or overhead makes little difference. Too many reasons why were already provided. A short application note from an industry professional demonstrates the concept. Both underground and overhead wires require the same protection:
http://www.erico.com/public/library/fep/technotes/tncr002.pdf

Thanks for finally linking an external site.

Here's that company's plug-in protection: http://www.erico.com/products/CritecPLF.asp

It includes phone-line protection. I guess they feel phones are vunerable that late too.

 

[JerryLove]

What will a power strip do to delicate equipment? Earth a surge destructively through delicate equipment.

Use a semi-conductor to short over-voltage to a ground line (third pring) which will go back to the plug where it will follow a series of connected grounding lines to an earth ground line that runs own the side of my garage and into a long bar running under my house.

What do you think it will do?

That power strip must either absorb hundreds of thousands of joules, or earth a surge destructively through the adjacent appliance, or fail catastrophically.

Or open the circuit, or use a semi-conductor to short the circuit to ground.

And the manufacturer still does not claim to provide effective protection.

Are you talking about APC again? They guarentee their products to provide protection. That's pretty obviously a claim.

Again, an important parameter is that short (ie 'less than 10 foot') connection to single point earth ground.

If that were true: it would be impossible to protect (say) a radio antanee struck more than 10' about the ground.

Beyond that, you are just too ranty. You make statements obviously contrary both with reality and with other statements you've made (see above). You don't deviate even with presented with directly contrary claims (see "APC claims to guarentee against damage" as an example), and you don't actually explain/defend any of the issues raised.

So explain to me how APC can simultaniously guarentee surge protection (whether they honor that guarentee is irrllevent to this paragraph) and yet not claim surge protection?

 

[Chopper Greg]

First of all I want to say that as a Noob, I have found this discussion interesting, but as a Noob I am very hesitant to get involved with it as well due to the apparent heat of the discussion.

I am most hesitant to get involved but I am doing so to possibly clarify a few things.

First let me say that I am not an expert in anything.

OTOH, I have studied from a broad range of subjects and have a very strong interest in science, but I can also say that I have had the privilege of pulling security at military installations ( such as NORAD ), that required security clearances or be escorted by someone who does have the clearances to enter, and as such had the opportunity to talk to highly trained personal.

As to how that influences this particular discussion, I was assigned to escort a crew who installed a 10 meter satellite dish at an Air Force base in the area which included grounding it to military specification.

Why do munitions dumps and US Air Force facilities do not use that protector?

The US Air Force ( and for that matter most of the services ) uses a belt and suspenders approach.

In the grounding of the satellite dish not only did they ground the dish, they grounded the building with the support equipment and then the equipment it's self, all on separate systems.

For the dish, a 10 ft copper rod ( that was about 9/16ths of an inch in diameter ), was driven into the ground about every 8 feet along the perimeter of the foundation with an extra rod at each of the 4 corners, about 18 inches from the foundation it's self.

To each of the rods a single cable was connected that ran in a circle around the entire foundation. Now I must point out that the top of the rods and the cable that connected it were about 2-3 ft below the surface of the earth and the connections were not simple mechanical connections. All of the cable / cable and cable / rod connections involved in the grounding system, were monolithic in nature in that copper thermite was used to form each connection, to eliminate any possibility of electrical or mechanical failure.

Leads were then taken off of the metal frame of the dish, at appropriate intervals and attached to the main earth lead. The connection of the cables to the frame were copper braid in nature as they were in places that could be inspected and replaced if they were showing damage.

The building that housed the support equipment, was essentially a Faraday cage that was grounded in a similar manner.

The equipment it's self, had surge protection built in to it, and while those surge protection sections were rated at higher surges than what most people could think about buy and using, they were considered disposable in that if everything else failed, the surge protection would provide the necessary protection and if necessary fail in a manor that protected the equipment behind it.

It was during this time that I found out that the military doesn't normally use things like power strips that have surge protection ( not that the power strips they use don't have surge protection - just that it's only one of many layers of protection ), because for the most part their systems either have it built in with greater levels of protection, or through simple redundancy.

The folks that installed the grounding system were professionals that install lighting protection systems around the area, and as they were installing the system, talk naturally evolved to lighting protection of homes and businesses and surge protection of the equipment in them, and they basically had this to say:

Homes and businesses are to have a certain level of earth grounding that are supposed to be installed ( or at least a in place ) through building codes. This is often accomplished by the use of electrical wiring and water pipes that are going to be installed anyway.

The problem occurs when direct strikes hit - while the standard system can and often does offer some measure of protection, the system just was not intended to handle such uncommon occurrences. It may be that poor materials were used, bad soil conditions, poor workmanship or just bad luck, but the results are the same, often the system in the average building, acts more like a common ground ( like might be found on your vehicle ) rather than a real earth ground, while a structure that is out fitted to handle direct lighting strikes, is going to have enhanced earth grounding properties.

Now anyone that has done much with electronic circuits knows, that while electricity does prefer to take the path of least resistance, it can and will send minor surges along all possible paths to ground, and if this means a spike through the wiring in your wall, even if it means that allot of electricity is trying to find it's way to ground or just a little, it is going to happen.

Making sure that your home does have a good earth ground is a very good idea for when those rare strikes occur, having surge protectors on your best equipment also protects from the stray voltages that are going to occur while the main surge is going to ground. If your house doesn't have a a good earth ground, then those stray voltages are going to be higher - is a simple surge protector going to protect in those situations? It might or might not, depending of the severity and just how far it has to goto find an easy path to ground.​

Now the guy that eventually became my brother-in-law, was tapped by the base commander ( F.E. Warren AFB in Cheyenne WY ) to rebuild the computers on base used for everyday operations ( in some cases they were 286's and 386's that were originally installed ).

Part of the process that occurred when it came time to install the computers in the office that it was being put in, was to install a line filter / surge protector between the computer and the wall, and this was for every single computer on base - even for the computers in buildings that had surge protection on the main electrical entry point of the building, but had yet to have it's over all electrical upgraded over what was installed when the building was modeled into it's current function ( 20-30 years in some cases ).

One of these buildings took a lightning strike and while they still lost the half dozen computers closest to the strike, the rest were fine, even though some equipment ( mainly radio's and a couple VCR's ) in other parts of the same building was lost to the same strike.

The points being that:

1) The Air Force ( and the other military services ) do use surge protectors, especially in buildings that have not been renovated in some time ( and as a consequence probably have deficient electrical protection ) and it is another part in a very large set of components, and not as a stand alone, it just that for many of the applications they are not a part of what the likes of you or I could afford to buy.

2) Surge protection as found in the likes of APC or other similar products, may not protect from strikes that hit the room they are in, they can ( when used with a reasonable earth ground ) limit how far the damage occurs, when it does happen.

 

[westom]

The building that housed the support equipment, was essentially a Faraday cage that was grounded in a similar manner.

The equipment it's self, had surge protection built in to it, and while those surge protection sections were rated at higher surges than what most people could think about buy and using, they were considered disposable in that if everything else failed, the surge protection would provide the necessary protection and if necessary fail in a manor that protected the equipment behind it.

Appreciate that I have said all homes need surge protectors. Most homes have no effective protection - especally if using plug-in protectors. Others may have obfuscated that point by promoting ineffective protectors - that do not even claim protection. Then deny the value of the only protectors that are effective - properly earthed 'whole house' protectors - to promote ineffective APC products.

Your description is the same concept found in my application note cited earlier - :
http://www.erico.com/public/library/fep/technotes/tncr002.pdf

One radio station accomplished the same solution using a different technique:
http://scott-inc.com/html/ufer.htm
But in every case, earthing is the only and essential component in any protection system.

So that a protector will be even more effective and so that the single point earth ground will be the best ground; a buried ground loop (or Ufer ground or something equivalent) is routinely installed. This should be required for every new home because a protector is only as effective as its earth ground.

All electronics - even retail stuff - contain internal protection. For example, power supplies must withstand thousands of volts without damage. Many interface semiconductors are now rated to withstand 2000 and 15,000 volts. In most cases, anything that an adjacent protector (or UPS) would do is already inside electronics.

Apparently you did not understand what those additional devices do. You said, "if everything else failed, the surge protection ... if necessary fail in a manor that protected the equipment behind it." That implies it can disconnect from a surge. It cannot. Nothing stops surges. Furthermore, surges are too fast; done in microseconds. Nothing will disconnect fast enough or wide enough. Any protector that fails (opens) provides no protection.

Your post demonstrates how protection has been done for 100 years. How protection is installed in facilities that must never have damage. All homes need a protector. One protector connected to single point ground. Earthing that must meet and exceed post 1990 National Electrical code. The APC has no earthing connection - therefore it also does not claim to provide protection. Those who recommend the APC will not even discuss what provides protection. All homes need a surge protector - one that is effective and can actually provide protection. Why does the Air Force install proper earthing? Damage must never happen.

One final point. That base has a problem. When damage occurs to electronics, the proper response is to find that system defect and fix it. Starts with an analysis of single point ground - to find a human created defect that permitted computer damage.

From the US Air Force training manual is the requirement for 'whole house' protectors. - what every building and homeowner needs:
> 15. Surge Protection.
> 15.1. Entering or exiting metallic power, intrusion detection, communication,
> antenna, and instrumentation lines must have surge protection sized for
> lightning surges to reduce transient voltages to a harmless level. Install the
> surge protection as soon as practical where the conductor enters the interior
> of the facility. Devices commonly used for this include metal oxide
> varistors, gas tube arresters, and transzorbs.

That recommended APC violates what the Air Force requires from effective protectors.

 

[Hi Ho]

I find this discussion to be quite interesting.

I have been considering installing a whole house protector for some time. Is a unit such as this adequate?

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&productId=100396389&langId=-1&catalogId=10053&ci_sku=100396389&ci_src=14110944&cm_mmc=shopping-_-googlebase-_-D27X-_-100396389

 

[Chopper Greg]

Appreciate that I have said all homes need surge protectors. Most homes have no effective protection - especally if using plug-in protectors.

I have to disagree.

No one is saying that plug in protection will take care of direct strikes other than as a line of defense.

Plugins are surge supressors - and that is what they do.

They protect from the secondary currents.

If you look closely at the manuals of whole house protectors, even they say that they will not survive a direct lighting strike coming into it, and even the best whole house protectors may still let up to 15% of the surge through, and this is where the plug in strips do their job - by dealing with the surges that get pass the whole house unit.

Whole house units can only protect from surges originating from the powerline that comes into the house - they can not protect from direct strikes that enter the house by way of the roof or a wall, thus entering the house wiring by a means other than the panel box.

Others may have obfuscated that point by promoting ineffective protectors - that do not even claim protection. Then deny the value of the only protectors that are effective - properly earthed 'whole house' protectors - to promote ineffective APC products.

I disagree.

Houses are expected to be properly grounded to begin with - in which case the addition of plug in protectors to deal with lessor surges that get's pass the main point of earth grounding, should be all that is needed.

The biggest issue is the fact that the market is overwelmed with cheap $5 surge supressor strips that really are ineffective against loads, while a quality plug in supressor is going to run $15 - $20 ( and more ) at a bare minium.

But in every case, earthing is the only and essential component in any protection system.



So that a protector will be even more effective and so that the single point earth ground will be the best ground; a buried ground loop (or Ufer ground or something equivalent) is routinely installed. This should be required for every new home because a protector is only as effective as its earth ground.

All electronics - even retail stuff - contain internal protection. For example, power supplies must withstand thousands of volts without damage. Many interface semiconductors are now rated to withstand 2000 and 15,000 volts. In most cases, anything that an adjacent protector (or UPS) would do is already inside electronics.

Apparently you did not understand what those additional devices do. You said, "if everything else failed, the surge protection ... if necessary fail in a manor that protected the equipment behind it." That implies it can disconnect from a surge. It cannot. Nothing stops surges. Furthermore, surges are too fast; done in microseconds. Nothing will disconnect fast enough or wide enough. Any protector that fails (opens) provides no protection.

Not realy.

If you take the time to reread what I typed you will find that it doesn't actualy open a switch:

The equipment it's self, had surge protection built in to it, and while those surge protection sections were rated at higher surges than what most people could think about buy and using, they were considered disposable in that if everything else failed, the surge protection would provide the necessary protection and if necessary fail in a manor that protected the equipment behind it.

If it helps, you can think of it as a high tech electronic fuse, in that only a limited amount of current can pass through and if a current above a given amount tries, it fry's the protective circut thus protecting the expensive equipment behind it - IOW, it's not that it can't fail - it's allowed to fail if it means protecting the hard to replace equipment.

Your post demonstrates how protection has been done for 100 years. How protection is installed in facilities that must never have damage. All homes need a protector. One protector connected to single point ground. Earthing that must meet and exceed post 1990 National Electrical code. The APC has no earthing connection - therefore it also does not claim to provide protection. Those who recommend the APC will not even discuss what provides protection. All homes need a surge protector - one that is effective and can actually provide protection. Why does the Air Force install proper earthing? Damage must never happen.

This is taken from a wiring manual of a whole house surge protector:

http://www.smarthome.com/manuals/4860.pdf

WARNING: CAT. NOS. 51120-l AND 51120-3 TVSS
DEVICES ARE NOT LIGHTNING ARRESTORS AND
WILL NOT SURVIVE LIGHTNING STRIKES IN CLOSE
PROXIMITY TO THE PREMISES OR SUSTAINED
OVERVOLTAGES

I found simular statements for other whole house protectors.
In Other Words - not even whole house protectors will handle lighting strikes in the imeadate proximity & dirrect strikes.

What you need to deal with imeadate proximity & direct strikes is a Lightning Arrestor, which is whole different animal - well maybe not totaly different, but they are installed differently and work in places where whole house surge devices do not.

One final point. That base has a problem. When damage occurs to electronics, the proper response is to find that system defect and fix it. Starts with an analysis of single point ground - to find a human created defect that permitted computer damage.

From the US Air Force training manual is the requirement for 'whole house' protectors. - what every building and homeowner needs:
> 15. Surge Protection.
> 15.1. Entering or exiting metallic power, intrusion detection, communication,
> antenna, and instrumentation lines must have surge protection sized for
> lightning surges to reduce transient voltages to a harmless level. Install the
> surge protection as soon as practical where the conductor enters the interior
> of the facility. Devices commonly used for this include metal oxide
> varistors, gas tube arresters, and transzorbs.

Your right, that base had problems - but it had them just like every other base at that time, when the Commander in Cheif was slashing the military budget but still requiring that same level of operations be maintained, so things like basic maitance and remodeling buildings to replace out dated equipment suffered, and it was this that alowed the lighting to track a path through the wall of the building ( leaving a hole that a basketball could be shoved through ) and into the water pipe in the floor.

 

[JerryLove]

Others may have obfuscated that point by promoting ineffective protectors - that do not even claim protection. Then deny the value of the only protectors that are effective - properly earthed 'whole house' protectors

Actually not a single person has done so.

1) The Air Force ( and the other military services ) do use surge protectors

But in every case, earthing is the only and essential component in any protection system.

You don't seem to interact with anyone's posts. Glad it's not just me.

You make statements obviously contrary both with reality and with other statements you've made (see above). You don't deviate even with presented with directly contrary claims (see "APC claims to guarentee against damage" as an example), and you don't actually explain/defend any of the issues raised.

So explain to me how APC can simultaniously guarentee surge protection (whether they honor that guarentee is irrllevent to this paragraph) and yet not claim surge protection.

 

[westom]

I have to disagree.
No one is saying that plug in protection will take care of direct strikes other than as a line of defense.

Plugins are surge supressors - and that is what they do.

They protect from the secondary currents.

So it protects from surges that are not destructive? Spend $25 or $150 to protect from secondary currents that are not destructive? Even 386 computers contained internal protection that make trivial currents irrelevant. Spend $25 or $150 for the same protector circuit selling for $7 in a grocery store - to protect from currents that are not destructive?

View spec numbers for a minimally sufficient 'whole house' protectors - ie cited by Hi Ho. A typical lightning strike is about 20,000 amps. Hi Ho asked about a 'whole house' protector from Home Depot - rated at 48,000 amps. You say that 48 kamp protector cannot conduct a 20 kamp direct lightning strike?

That protector is more than sufficient. View the numbers. Meanwhile, a direct lightning strike is also earthed elsewhere by the primary surge protection system.
http://www.tvtower.com/fpl.html
Much less than 20,000 amps is earthed by a more than sufficient 'whole house' protector. Then even more of that surge gets earthed by other neighborhood homes. A 'whole house' protector easily earths direct lightning strikes. BTW, this was explained, with numbers, in an IEEE paper many decades ago. I am simply repeating what has been well understood and demonstrated for over 100 years. Another sentence repeated because somehow these realities get ignored in the replies.

A properly sized 'whole house' protector earths direct lightning strikes and remains functional. Even the numbers say so. It also makes lesser (secondary currents) irrelevant. Protection inside every appliance further makes those secondary currents irrelevant. That's two reasons why secondary currents are irrelevant. Install one 'whole house' protector so that the rare and destructive surge does not overwhelm protection in every appliance.

What plug-in protector claims to protect everything - let alone claims to protect anything? Where are those plug-in protector specs that even claim protection? I still don't see those numbers posted here. I do not even see protection claims for a *subjective* secondary current. Where is that protection defined with numbers? Since the plug-in protector is a complete protection solution, then where are its numbers? Just repeating another fact that gets ignored in every reply.

Why do those scary pictures exist? Same circuit that sells for $7 in a grocery store also sells for $25 or $150 from APC and Monster Cable.

Stated previously and noted again because you assumed all homes are properly earthed. Earthing must meet ... *and exceed* .... post 1990 National Electrical code. For example, an earthing wire from the breaker box may go up over a foundation and down to an electrode. That meets 1990 code - for human safety. But is insufficient for transistor safety. Wire is too long (wire length - not thickness - defines impedance). Has sharp bends. Ground wire, bundled with other non-grounding wires, further compromises protection. Code only defines earthing for human safety. Same earthing exceeds code for transistor safety.

Breaker box ground wire should go through the foundation and down to earth. Every foot shorter means even better surge protection. Eliminate sharp wire bends. Ground wire is separated from other non-grounding wires. Concepts that are not discussed when a plug-in protector sells for obscene profits rather than for protection.

Numerous sources discuss low impedance. That plug-in protector manufacturer will not. It is marketed to people who ignore the word 'impedance' and never even ask a simple questions such as, "Where does that energy get dissipated?"

Where does energy from secondary currents get dissipated? If it protects from that energy, then does that energy just magically disappear?

Your telco, connected to overhead wires all over town, suffers about 100 surges with each storm - and no damage. Above explains why your telco earths 'whole house' protectors (so that direct lightning strikes cause no damage). And does not waste money on expensive, ineffective plug-in protectors. This paragraph alone is more than sufficient to define the difference between 'whole house' and plug-in protectors.

Let's add Martzloff's 1994 IEEE paper. In his first conclusion, Martzloff says a plug-in (point of use) protector can even contribute to appliance damage (as we engineers also discovered):
> Conclusion:
> 1) Quantitative measurements in the Upside-Down house clearly show
> objectionable difference in reference voltages. These occur even when
> or perhaps because, surge protective devices are present at the point
> of connection of appliances.

Moving on: a frying protector circuit means no protection. It fries to absorb hundreds of thousands of joules? Total nonsense. And a violation of MOV manufacturer specifications. MOVs that fry provide no protection, violate what the MOV manufacturer intended, AND can even create those scary pictures. But when one recommends on hearsay, then a frying protector means protection? Did those scary pictures not mean anything?

In another discussion, one said, "My protector sacrificed itself to save my computer." A perfect example of observation resulting in a junk science conclusion. Add electrical facts he never learned. That surge confronted a computer and protector equally. That surge was too trivial to overwhelm protection inside the computer. But easily destroyed a grossly undersized plug-in protector. Grossly undersizing increases profits AND gets the naive to recommend it to friends. Any protector that 'fries' provides ineffective protection and violates the "Absolute Maximum Parameters" found in every MOV manufacturer datasheet.

Or view the V-I charts for MOVs. How excessively high is that voltage if a MOV fries? A 330 volt protector that fries means a voltage well above 900 volts confronts the 120 volt appliance. More facts with numbers. What kind of protection is that? Fortunately, appliances already contain significant protection. The protector sacrificed itself on a surge too small to damage anything else - also called ineffective protection.

A protector acting "as a high tech electronic fuse, in that only a limited amount of current can pass through" - total nonsense. Read numbers on any fuse or circuit breaker? For example, a glass cartridge fuse says 250 volts. If it opens (blows) to block a surge greater than 250 volts, then the open fuse continues to conduct. Does not stop anything. Did you read those numbers?

Same applies to surges. Learn another electrical concept called constant current source. Any attempt to stop a surge current means voltage increases, as necessary, to blow right through that blocking (limiting) device. Nothing stops (or limits) a surge current. That high tech fuse concept is popular myth promoted when basic electrical knowledge does not exist.

Why did lightning strike Ben Franklin's wooden church steeples? Wood also tried to limit the surge current. Therefore voltage increases, as necessary, so that wood conducts that current. That current will flow no matter what tries to impede it. When voltage increases, then energy is dissipated destructively in wood. Same current times higher voltage means more destructive energy. How did Franklin stop surge damage? He gave lightning a more conductive path to earth. Same massive current times near zero voltage means no energy and no destruction.

Any attempt to limit surge current means voltage increases AND that same surge current still flows.

Let's add another professional who defines what a protector really does. Dr Kenneth Schneider:
>Conceptually, lightning protection devices are switches to ground. Once a threatening
> surge is detected, a lightning protection device grounds the incoming signal
> connection point of the equipment being protected. Thus, redirecting the threatening
> surge on a path-of-least resistance (impedance) to ground where it is
> absorbed.
>Any lightning protection device must be composed of two "subsystems," a switch
> which is essentially some type of switching circuitry and a good ground connection-to
> allow dissipation of the surge energy. The switch, of course, dominates the design
> and the cost. Yet, the need for a good ground connection can not be emphasized
> enough. Computer equipment has been damaged by lightning, not because of the
> absence of a protection device, but because inadequate attention was paid to
> grounding the device properly.

Of course if lightning is blowing through a wall to obtain an interior water pipe, well, then entire building has no effective earthing. Not even a properly earth lighting rod. But again, what defines protection? A sharp or a blunt lighting rod? Irrelevant. Even a lighting rod is only as effective as its earth ground.

Using numbers, obviously a 'whole house' protector earths direct lightning strikes - and remains functional. Even makes secondary currents irrelevant. And protects everything since even smoke detectors need that proetction. No plug-in protector claims protection let alone do any of those things. But again, where are those manufacturer spec numbers? How does a protector magically make energy just disappear? How does that 2 centimeter part in a protector magically limit a current that even three miles of sky could not limit?

What defines each 'layer of defense'? Each single point earth ground defines each protection layer. A 'whole house' protector is secondary protection. Also inspect your primary surge protection system:
http://www.tvtower.com/fpl.html

 

[westom]

I find this discussion to be quite interesting.
I have been considering installing a whole house protector for some time. Is a unit such as this adequate?

That Intermatic 'whole house' protector is an effective solution (assuming you have addressed what provides protection - earthing).

For example, it is rated at 48,000 amps. That means it earths a direct lightning strike without damage. And it has the 'always necessary' dedicated wire for a short connection to earth. Just a few reasons why you would know the Intermatic is effective - and why the APC does not even claim to provide surge protection.