Whole house surge suppressor?

[thammel]

So Mike Holmes is always showing that they put in a whole house surge suppressor with their new panel work. Have any of you done this? What suppressor do you recommend? Will the one suppressor take care of all subpanels?

Thanks,
Tom

 

[Dick in Wisconsin]

Re: Whol house surge suppressor?

So Mike Holmes is always showing that they put in a whole house surge suppressor with their new panel work. Have any of you done this? What suppressor do you recommend? Will the one suppressor take care of all subpanels?

Thanks,
Tom

This is AN EXCELLENT question! Do these really work? Or they just as good as an expensive surge protector at the HDTV, Blu-Ray, Receiver, Cable box, DVR, etc.

 

[gatchel]

Re: Whol house surge suppressor?

Yes they are good insurance but nothing is guaranteed...

http://www.garagejournal.com/forum/showthread.php?t=106933

I like Ditek Products personally but there are may quality brands available.

 

[ddawg16]

Re: Whol house surge suppressor?

I have been researching those now for the past couple of months. I'm in the middle of a 2-story addition which involves me having to install a new load center (breaker panel).

There are two basic flavors....

Integrated Circuit Breaker - Surge protector is about the size of a double ckt breaker and plugs into 2 spaces in your panel. Some have outputs so it can be used as a 50A breaker....others do not. Almost all have indicators to show if it fired.

External - You mount it external to your breaker panel...but it wires to an existing double breaker.....The ones I have seen wire to a 30 or 50A breaker. The reason for the breaker connection is twofold....1st...if you have an event that is enough of a surge, the breaker trips. This gives you a visual indication that you had a surge...2nd...it somewhat protects the surge protector and the devices downline from it. I'm trying to see if there are any that tie directly to the power buss after your main breaker. I have a feeling they don't.


It's important to understand that most 'surge protector outlet strips' typically use just an MOV. The MOV is a device that 'fires' when the voltage reaches a certain point...the problem is that most of the MOV's out there end up getting fried by the event....which means they won't work again....the bigger problem is that there is no indication that it's fried....

The whole house units can take a lot more abuse....and when connected via a CB, are not distroyed by a surge.

Even if you have a whole house surge protector, you should also have a smaller point of use surge protector. APC has some really inexpensive UPS's now that have integral surge protection. I have bought a unit for about $60 that not only had surge protection but would also keep the computer alive for about 15 minutes...or a CFL light for a couple of hours (if you don't mind the beeping).

 

[MBfreak]

Re: Whol house surge suppressor?

A MOV surge protector, if it is correctly designed with regards to thermal capability, does a very good job of clamping a surge( more correct word is transient) voltage to the level specified on it. The surge voltage is also influenced by the surge current, which may reach 10 kA or higher. But it is good for only very short surges, as typically associated with a lightning strike. The peak current thru the suppressor lasts for less than 100µs.
The energy dissipated is quite high, so the "whole house" suppressor is best placed where the overhead feeder enters the house. The types that have silicone rubber as exterior isulation can not explode and cause damage and fires.
Stay away from epoxi or ceramic outer insulation.

However, at transient voltage rises of this magnitude, the laws of electricity are somewhat un-intuitive. As the surge voltage as clamped by the suppressor propagates downstream, it increases in amplitude. How much depends on the circuit physics ( L and C) If it arrives at ie a motor or transformer terminal it "bounces back" and the return point will reach around the double incoming transient voltage.
So, if you have expensive loads that are connectd most of the time, a secondary , smaller , surge arrestor up close to it is a good thing..

I would be wary of any sweeping claims from suppliers or experts of the " I absolutely know" variety when it comes to surge voltages. If you really need to know you will have to determine all circuit parameters, apply solid power engineering knowledge and a fancy real time calculation program ( such as PSCAD/EMTDC). However , this is way OT for residential stuff.

If you are really concerned and your property is fed by an overhead line, consider two things.
Does the overhead line have an "umbrella wire" at least 2 feet above the feeder?. This is a great way to reduce the impact severity of a direct lightning strike .
Is it at all possible to bury the feeder for the last hundreds of feet?

And if you have a cable feeder, the physics comes in again. You need a set of suppressors at each end. But the worst case scenario, a direct lightning hit close up, is totally eliinated.

Best regards

Ola

 

[matt151617]

Re: Whol house surge suppressor?

I installed an Intermatic IG1240RC3, costs about $100 on Amazon. This one piggybacks off of an existing 240v breaker, but I installed it on its own set of breakers. You still need surge protector power strips in additon to the panel-mounted one.

They also make ones that plug right into the panel like a breaker, they look sort of like a GFI or AFI breaker with the curly white wire. Those are the easiest to install. Many power companies also will install one at the meter. It'll cost $5 a month or so, but they'll install it and replace it free if it fails.

Another good idea is to get a surge protector for your cable and phone lines. However, as mentioned, nothing is going to protect from a direct lightning strike, or even one somewhat nearby that gets into the lines.

 

[skruft]

Re: Whol house surge suppressor?

They are useful things but they do take up two breaker spaces.

 

[pattenp]

Re: Whol house surge suppressor?

Not all of them do. Some will use existing breaker as long as the breaker can take two wires.

They are useful things but they do take up two breaker spaces.

 

[Teken]

Re: Whol house surge suppressor?

Many power companies also will install one at the meter. It'll cost $5 a month or so, but they'll install it and replace it free if it fails.

I second this as well. If your POCO offers this service go for it. Of all of the money you will ever spend. This is the best $5.00 you can ever spend and be happy about.

This is the only primary surge arrestor you can have that protects the service panel, where it matters the most. Installing a secondary surge arrestor at the service panel is also wise and cheap insurance.

This will ensure all of those expensive appliances are well protected and live a nice long life.

Consider how much you have invested in just a air conditioner, fridge, stove, dishwasher, furnace, water heater, washer / dryer, microwave, coffee maker, etc.

Never mind all of the other related electronic device you may have from TV, game console, PVR, DVD player, Stereo system etc.

As the other members have stated as well: Having a point of use outlet, along with UPS back ups is smart thing. If your systems are important to you many of the APC branded UPS systems come with *Power Chute* power down software.

This allows you, or the computer to remotely turn off devices . . . In the industrial world this is necessity, not a just a nice to have.

With respect to the UPS device: It goes with out saying that you must ensure you size the load to the UPS. Regardless of what the maker may claim you must always perform a monthly live test and time the UPS for operational run time.

This is the only validation method that will stress, test, and confirm the systems ability to operate and provide AC power to those devices. It will also confirm for you if the *stated run time* is actually there and protecting your assets.

Often times as systems get older *power supplies* start to draw more current than they use to. This is why live testing of the UPS is required to ensure a real world expectation of what can be provided.

At the end of the day the cheapest method of protection is to turn off each of the breakers one at a time, then turn off the primary disconnect at the service entrance.

This only helps you when you're on site and have the for thought to do so!

Teken . . .

 

[jvitez]

Re: Whol house surge suppressor?

I had our electrician install one on each of the two service panels. They mount as a breaker on the top of the bus bar just after the main disconnect, protecting everything down stream. I still plug most things into MOV surge protectors: belt and suspenders. My pants are not falling down! Our power is very stable so no need to give them a workout yet, which is just the way I like it.

 

[Tom in Seattle]

Re: Whol house surge suppressor?

My new QO panel will have a QO2175SB 2-Pole Surge Arrestor installed in the top, left space. Hopefully this will provide some protection for the installed appliances.

My expensive audio and video equipment is protected by secondary surge filters made by Brick Wall (http://www.brickwall.com). No MOVs are used in these heavy-duty surge filters. They are relatively expensive, but still far, far less costly than replacing an expensive preamp or amp.

 

[rlitman]

Re: Whol house surge suppressor?

It's important to understand that most 'surge protector outlet strips' typically use just an MOV. The MOV is a device that 'fires' when the voltage reaches a certain point...the problem is that most of the MOV's out there end up getting fried by the event....which means they won't work again....the bigger problem is that there is no indication that it's fried....

The whole house units can take a lot more abuse....and when connected via a CB, are not distroyed by a surge.

Yes, and no.

There's nothing wrong with an MOV protector. It will remove more energy from a transient than any other technology, and has the fastest response time of any option. Yes, it is consumed a little bit with each surge, but any quality whole house TVSS will include an indicator that tells you when it is worn out.

No, the circuit breaker will NOT prevent a surge from slowly consuming an MOV. The currents involved in a surge can be enormous (hundreds, and perhaps thousands of times the label on the breaker, as was so well spelled out above by MBfreak), but the duration is so short that no breaker (or even a fuse) could trip.

Don't be concerned that a circuit breaker between the TVSS and the main bus will stop it from fully suppressing the surge. The time frame of a typical transient, is so short, that the impedance of the path is far more important than the resistance. Because of this, it is important to have the wiring to the TVSS done cleanly, with no sharp bends (radius everything).

Oh, and although it is counter-intuitive, they work best at the BOTTOM of the bus (assuming your main lugs are at the top).
This is due to the impedance issue above, and the high frequency wave nature of a surge. Installed at the top, more of the transient will continue down the bus to the end, and be reflected back. Installed at the bottom, the surge will travel down the bus (and not much will actually travel down each branch circuit because of their relatively high impedance compared to the rest of the bus in the panel), and instead of reflecting off the bottom, it will be absorbed by the TVSS.

Also, these devices (unlike a series mode system, which does make some sense for more sensitive devices, further down the line), absolutely require a good grounding system. If your grounding system is sub-standard, they really don't help much, so get that in order first.

 

[westom]

Re: Whol house surge suppressor?

So Mike Holmes is always showing that they put in a whole house surge suppressor with their new panel work. Have any of you done this? What suppressor do you recommend? Will the one suppressor take care of all subpanels?

Many confuse two completely different devices because both are called protectors. You have two choices. Somehow a magic strip will block thousands of voltage and absorb hundred of thousands of joules. Or a surge is earthed before it can even enter the building. Then thousands of volts does not exist. And hundreds of thousands of joules dissipate harmlessly outside.

The first solution is typically so undersized as to only protect from surges that are typically not destructive. Their failure gets many naive consumers to recommend them.

The second solution means you never even knew a surge existed. Even the protector remains functional after direct lightning strikes. This superior solution is found in every facility that cannot have damage (ie commercial broadcast stations). And is typically tens or 100 times less money?

The second solution: actually no protector does protection. For example, the cable TV wire needs no protector. The best protection is a wire that connects from the cable, low impedance (ie 'less than 10 feet') to single point earth ground. That wire makes a connection to what does the protection - ground.

Some wires cannot be connected directly to earth (ie AC electric, telephone). So we compromise. We make the same connection with a protector. That is what all protectors do. Either connect that energy harmlessly to earth. Or do virtually nothing.

Critical is that every incoming wire make a short (ie 'less than 10 foot') connection to the single point ground. Because wire length (rather than wire thickness) is a critical parameter. A protector is only as effective as its earth ground. Examples of compromised protection: a ground wire has sharp bends going up over the foundation and down to an earthing electrode outside. That copper ground wire would be too long, too many sharp bends, and bundled with other non-grounding wires. Best solution is to route the ground wire through the foundations and down to earth. Then the panel box protector does even better protection.

Protectors are simple science (hyped into miracle boxed by advertising). The art is the earthing. Best time to install protection is when the footings are poured. This solution, first pioneered in mentions dumps, is why their protectors are superior. Seek examples of Ufer grounds.

However, anyone can still upgrade the earthing. Not only must the connection to single point ground be low impedance (ie 'less than 10 feet'). But everything done to make the earthing better only makes protection better.

The effectiveness of a protector during one surge is determined by its earth ground. Life expectancy of a protector over many direct lighting strikes is determined by its current rating. A 'whole house' protector must be as least 50,000 amps. Then 20,000 amp lightning strikes do not even harm the protector. These superior solutions even sell in Lowes and Home Depot under the Cutler-Hammer name for less than $50. Other responsible companies sell them including Intermatic, Leviton. ABB, Square D, Ditek, Polyphaser, Siemens, and GE.

A protector earthed in the secondary panel can actually make damage easier. The term was repeated often because it is critical: single point earth ground. Low impedance (ie 'less than 10 feet'). These concepts were well understood even 100 years ago. Notice how many only know about myths from hearsay and advertising. Do not know what was well understood over 100 years ago.

Take a $4 power strip. Add some 10 cent protector parts. Sell it for $30 or $120. With obscene profit margins, then advertising can replace proven science.

Instead learn why your telco's switching computer, confronted by about 100 surges with each thunderstorm, is not destroyed. A 'whole house' protector, properly earthed, is the only solution found in every facility that cannot have damage. And it is your least expensive solution.

 

[Roots]

Re: Whol house surge suppressor?

I whole heartedly believe that it's only a matter of time before code requires them on new structures.

 

[Charles (in GA)]

Re: Whol house surge suppressor?

I whole heartedly believe that it's only a matter of time before code requires them on new structures.

Just as soon as the manufacturers pay off the code making committees well enough. I am fully convinced that much of the modern code is driven by lobbying and some sort of "good old boy system". Some of the things they have mandated AFCI's for instance, are simply not up to the job (yet) and to have required them is absurd. Same goes for tamper proof receptacles. How many kids get electrocuted each year by poking things in receptacles? I have no idea, but its not something you hear of or read about. Yes, I did it when I was a kid, didn't get killed, learned a lesson. But to force everyone to have cheap quality, Chinese made receptacles to keep kids from poking stuff in them..... I don't have any kids in my house, never will, yet if I add on or build anew, I would be required to have them. (and change them out for commercial receptacles just as soon as the inspections were done, new owner would get handed a box of receptacles and told if they wanted them, install them.)

Don't ever let the NFPA get ahold of your address. They have mine, and its rare that a day goes by that I don't receive something from them, catalogs, mailings about "seminars" on this or that, mailings on training courses, classes, etc. Its all about money.

Charles

 

[frankush]

Re: Whol house surge suppressor?

Today's modern codes are influenced by lobbyists. You're dead right about AFCI's. Think about the market and the billions of dollars generated by the code mandated use of AFCI's. The money that manufacturers spent on lobbyists is nothing compared to the "new" revenue it created. And.......... they don't work worth a damn. Maybe someday they'll be able to tell the difference between a vacuum and a true arc fault.

 

[pattenp]

Re: Whol house surge suppressor?

My whole house surge protector and my individual outlet surge protectors saved all my electronics from being fried. Verizon was burying fiber optic cable and flo-bored through me and my neighbors power cable. My neighbor lost two flat screen TV’s a home theatre system and a microwave and some other stuff. I lost the whole house surge protector and 3 individual outlet surge protectors. Glad I had them. Now I have to wait for Verizon to pay my $300 claim. My neighbor’s claim is around $3000.

 

[westom]

Re: Whol house surge suppressor?

I lost the whole house surge protector and 3 individual outlet surge protectors.

Learn from the experience. Your system has a defect. If the 'whole house' protector was properly earthed, then no plug-in protectors failed. The 'whole house' solution protected them. Protection is not provided by a 'whole house' protector. Protection is provided by what that protector connected to - the earthing. Damage suggests earthing was insufficient. May have only met code - therefore insufficient. When replaced, also have the electrician upgrade what should have provided better protection - the earthing.

Protectors do not protect by failing. Protectors work by connecting a destructive current harmlessly to earth. Unfortunately we cannot test an installation. Learn from mistakes when a transient does damage. Your damage implies something should be better.

BTW, was that 'whole house' protector at least 50,000 amps?

 

[71flh]

MOVs are one time devices. If you get a lightning strike and the MOV is used, its pretty much toast. You have no way of knowing if it is, or isn't good.

MOV means metal oxide varistor. That means variable resistor. Lightning is high voltage and when an MOV sees that the var part kicks in and its resistance goes down. That is, it shorts to drop that voltage. MOVs are not typically large devices. Think of a disk the size of a quarter on the smaller ones.

Once used, they're toast.

A surge protector at the service entrance assumes lightning will strike the pole (or something near the service) and try to enter the house through the service and therefore the surge protector. Or the ground and slink in that way.

Electricity, especially high voltage and lightning isn't so cooperative. There are no guarantees.

Of course, these are my theories... I may be wrong. Tell me if I am!

 

[westom]

MOVs are one time devices. If you get a lightning strike and the MOV is used, its pretty much toast.

A typical lightning strike is 20,000 amps. So a minimally 'whole house' protector is 50,000 amps. Any protector that fails is not providing effective protection.

Second, if an MOV fails on a first transient, then it was grossly undersized. That failure gets a majority to recommend it. Take a $4 power strip. Add some ten cent protector parts. Sell it for $40 or $100. An obscene profit margin. Then when it fails, a naive consumer will recommend it to friends and buy more. Effective protectors remain functional so that nobody even knew a surge existed. But that would not promote sales.

Third, an MOV manufacturer defines testing:

The change of Vb shall be measured after the impulse listed below is applied 10,000 times continuously with the interval of ten seconds at room temperature.

A failed MOV only has a changed threshold voltage. Why 10,000 transients? After 10,000 transients, the MOV must not fail catastrophically. It must only degrade. Being properly sized would not increase profits.

Why does a protector fail on a first transient? Grossly undersizing increases profits and promotes sales. Then many will promote a myth rather than learn the science. Properly sized protectors remain functional. Demonstrated above at least three times and with numbers.

 

[pattenp]

Re: Whol house surge suppressor?

I have a Leviton Model 51120-1 rated at 50kA. I'm not sure how it was defective. It was installed exactly as required by the instructions.

Learn from the experience. Your system has a defect.
BTW, was that 'whole house' protector at least 50,000 amps?

 

[westom]

Re: Whol house surge suppressor?

I have a Leviton Model 51120-1 rated at 50kA. I'm not sure how it was defective.

A protector is only one component of the 'system'. Nothing said the protector was defective.

Protection is not provided by a 'whole house' protector. Protection is provided by what that protector connected to - the earthing. Damage suggests earthing was insufficient.

Please reread the recommendation.

When replaced, also have the electrician upgrade what should have provided better protection - the earthing.

A protector is simple science. Earthing is the art of protection.

 

[Rob_b]

It seems to me that the cost of these whole house systems is moot when considering the cost of the electronics they may protect. I have several highend "surge protector bars" on my electronics, a 1000va UPS on my computer/phone system and a 1500va ups on my HE furnace. I'd love to be able to say I am totally protected but anything could happen. On my computer, the APC UPS has a USB connection to my computer that gives me info on all the events that it monitors such as spikes, brown outs and black outs. Why is it that they never seem to happen when I'm here...

 

[westom]

I have several highend "surge protector bars" on my electronics, a 1000va UPS on my computer/phone system and a 1500va ups on my HE furnace. I'd love to be able to say I am totally protected but anything could happen. .

Be concerned about that furnace UPS. It outputs cleanest power when connected directly to AC mains. When in battery backup mode, a UPS is potentially harmful to power strip protectors and small electric motors. Because a UPS in battery backup mode is some of the 'dirtiest' power in a house. Simply view numbers.

For example, this 120 volt UPS outputs 200 volt square waves with a spike of up to 270 volts. Perfectly ideal electricity for all electronics. Because electronics are so robust. But potentially harmful to motorized appliances.

Where is protection provided by that UPS? View its spec numbers. How does it hundreds of joules make harmful transients (hundreds of thousands of joules) irrelevant? It doesn't. Manufacturer does not make protection claims in spec numbers. Manufacturer can claim 100% protection in advertising. Subjective claims are quite legal. Dishonest but legal.

Take a $4 power strip. Add some ten cent protector parts. It sells in Wal-Mart for $7. An equivalent circuit also sells under a Monster label for maybe $100. How did you define 'high-end'? By price?

Low end protectors do not have the dedicated wire to earth. Some will upgrade a Wal-Mart type protector to look expensive; to sell at inflated prices. Real 'high-end' protectors, instead, have one essential feature. The short and dedicated wire to earth. Any protector without that short connection to single point earth ground is the low end protector - no matter how much you paid for it. Price does not define quality.

Again, read the spec numbers. Where is the UPS spec number that claims surge protection? Why did they forget to discuss how 'dirty' that UPS output is? Because too many consumers ignore numbers. Too many consumers only listen to hearsay and subjective reasoning. Advertising works.

Your best protection with or without those 'high-end' solutions remains superior protection already inside every appliance. Protection increases when a protector is earthed - the 'whole house' protector. Then the rare and destructive transient does not overwhelm superior protection already inside every appliance.

 

[71flh]

westom, I did a bit of reading and it seems you're right. MOVs don't typically fail unless undersized. I stand corrected.

From your use of earth rather than ground I guess you aren't from the US...? Just interested in folks from different places.

Nice post on UPSs. I may have old BS info, but in the old days a UPS and a surge protector were two different devices.

 

[westom]

From your use of earth rather than ground I guess you aren't from the US...?

Different grounds exist. A digital ground on a computer motherboard is different from its analog ground; is different from its chassis ground; is different from a receptacle safety ground; is different from a floating ground inside a TV; is different from the ground beneath a shoe relevant to static electric discharge; is different form a bus bar ground inside the breaker box; is different from the single point ground used to avert ground loops among stereo components; is different from one type of earth ground relevant here. Single point earth ground.

Some grounds are interconnected. Others are not. But even inside a computer are electrically different grounds. Even the copper plate beneath a motherboard is electrically different at both ends of that board.

Same applies to appliance protection. Safety ground in a wall receptacle is electrically different from a single point earth ground. A ground relevant to appliance protection is earth ground. Not just any earth ground. Critical is single point earth ground. Multiple earth grounds can make appliance damage easier.

An example with numbers that demonstrates the concept. A 200 watt transmitter connects to a long wave antenna. Touch one spot and feel no voltage. Touch another spot to be shocked by over 100 volts. Why both 100 volts and zero volts on two spots of the same wire? These and other electrical concepts demonstrate why interconnected grounds are electrically different.

Essential to appliance protection is the relevant ground. One of many grounds. Single point earth ground.

 

[rlitman]

Be concerned about that furnace UPS. It outputs cleanest power when connected directly to AC mains. When in battery backup mode, a UPS is potentially harmful to power strip protectors and small electric motors. Because a UPS in battery backup mode is some of the 'dirtiest' power in a house.

That all depends on what sort of UPS you're talking about.
A quality UPS (not some piece of junk that switches a squareish wave from it's inverter which is indeed harmful to equipment) will put out a better quality sine wave with less harmonic distortion than you're getting from the power company's line. You get what you pay for.

westom, I did a bit of reading and it seems you're right. MOVs don't typically fail unless undersized. I stand corrected.

MOV's are a consumable. The DO fail eventually. It's just a matter of time in use. Undersized MOV's will fail faster than oversized ones (but only for the same reasons that it takes longer to drink a gallon container of milk in your fridge, than a quart sized one).

At work, we have three stages of 3-phase TVSS units, spec'd specifically for our application by the engineers at Schneider Electric (all of our panels are Square D). In each TVSS unit, there are three separate MOV modules, with each MOV module's potted assembly weighing in at over 5 lbs. In the past three years, I've replaced two modules that have failed (out of the nine that we have in continuous service), at a cost of about $2000 per module.

I don't know if there is such a thing as a larger MOV than this, but I sure haven't seen one. I wouldn't consider these to be undersized, considering the number of professional engineers who signed off on their installation, and YES, they do fail, but we're happy that these took the hits, and not our equipment.

 

[bud--]

The best information on surges and surge protection I have seen is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE in 2005 (the IEEE is a major organization of electrical and electronic engineers).
And also:
http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology in 2001

The IEEE surge guide is aimed at people with some technical background.

Where is protection provided by that UPS? View its spec numbers. How does it hundreds of joules make harmful transients (hundreds of thousands of joules) irrelevant? It doesn't. Manufacturer does not make protection claims in spec numbers. Manufacturer can claim 100% protection in advertising. Subjective claims are quite legal. Dishonest but legal.

Nonsense.

Francois Martzloff was the surge expert at the NIST, wrote many published technical papers and also the NIST surge guide. One of his technical papers investigated how much energy can reach the MOVs in a plug-in protector. Branch circuits were 10m and longer, and surges coming in on power wires were up to 10,000A (which is the maximum probable surge, as below). The maximum energy was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. Plug-in protectors with much higher ratings are readily available.

One reason the energy is so small is that at about 6,000V there is arc-over from the service panel busbars to the enclosure. After the arc is established the voltage is hundreds of volts. Since the enclosure/ground/neutral are connected to the earthing system that dumps most of the incoming surge energy to earth. (Earth/earthing used because of the inherent ambiguity of "ground".)

A plug-in protector connected correctly (see below) is very likely to protect from a very near very strong lightning strike. With high ratings (far above 35 joules) it is likely to never fail. That is why some manufacturers can have protected equipment warranties.

(Neither plug-in or service panel protectors work by absorbing a surge. They do absorb some energy in the process of protecting.)

Real 'high-end' protectors, instead, have one essential feature. The short and dedicated wire to earth. Any protector without that short connection to single point earth ground is the low end protector - no matter how much you paid for it.

Plug-in protectors do not protect primarily by earthing a surge. The IEEE surge guide explains (starting page 30) that they work by limiting the voltage from all wires (power and signal) to the ground at the protector. The voltage between wires going to the protected equipment is safe for the protected equipment.

Both the IEEE and NIST surge guides say plug-in protectors are effective.

When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like cable, also must go through the protector. Connecting all wiring through the protector prevents damaging voltages between power and signal wires. The NIST surge guide suggests most equipment damage is from high voltage between power and cable/phone/... wires.

You might use plug-in protectors on expensive equipment, particularly if it has both power and external signal wires.

Protection increases when a protector is earthed - the 'whole house' protector.

A service panel protector is a real good idea.
But from the NIST surge guide:
"Q – Will a surge protector installed at the service entrance be sufficient for the whole house?
A – There are two answers to than question: Yes for one-link appliances [electronic equipment], No for two-link appliances [equipment connected to power AND phone or cable or....]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO – but that does not mean that a surge protector installed at the service entrance is useless."

A service panel protector does not, by itself, protect from high voltage between power and phone/cable/... wires.

If there is a large surge current to the earthing system, the "ground" at the building may rise thousands of volts above 'absolute' earth potential. Much of the protection is a system where all wires (power/phone/cable/...) rise to together.

Another Martzloff technical paper looked at the maximum surge that was likely on power service wires to a house. The maximum was 10,000A per wire (which is mentioned in the IEEE surge guide). That is based on a 100,000A lightning strike to a utility pole next to the house with typical urban overhead distribution. It is, for practical purposes, the worst case.

The IEEE surge guide recommends a minimum rating of 20,000 to 70,000A, or for high lightning areas 40,000 to 120,000A (per hot wire). The protector will not be hit with those surge amps, they just mean the protector will have a long life. A service panel protector is very likely to protect anything connected only to power wires.

Then the rare and destructive transient does not overwhelm superior protection already inside every appliance.

"Every appliance" does not include surge protection. When included it is not "superior".


===============================
Martzloff also investigated transmission line effects (reflections) on branch circuits. Branch circuits are not likely to be long enough in homes for reflection effects. They may be long enough in commercial/industrial.

 

[tonycastec]

Great subject ! Wish it had been available when I researched and bought from Surgesupresion Inc. There is a lot of ineffective whole house surge suppressors available and it is a pity to waste the time and money on these ineffective items.
One thing to remember in dry areas (like where I live) is that if the ground rod is in dry-as-dust dirt,it won't be very effective in providing an easy path for the 'surge'.
The features of mine are:
Standard Features

25 Year Free Replacement Warranty
ANSI/UL 1449-2006 (Third Edition) Listed
CSA MC#241804
UL File Number E340498 and E315947
UL1283 Listed
Manufactured at an ISO 9001: 2008 Certified Facility
Industry Leading Let-through Voltage Performance
Circuit Encapsulation
Patented Fusing Methodology
Voltage Responsive Circuitry
Frequency Responsive Circuitry (Optional)
Discrete "All Mode" Circuitry
Advanced Internal Diagnostics
Component Level Thermal Fusing
120 kA Peak Surge Current per phase
Standard Composite Material NEMA 4X Enclosure
http://www.surgesuppression.com/products/power_panel_products.html

 

[Teken]

Lots of valuable contribution and feed-back. I would like to stress that all the best protection in the world, does not replace good home insurance. You need to be properly insured for the items you value the most.

It may be a long term pain and cost to you. But, rest assured if and when the time comes you won't be bitchen and moaning that your house / items won't be replaced because its not covered.

If you're able to leave key things unplugged when not in use. That is the only true method to ensure its survival during a lightning event.

All the grounding, surge arrestors, UPS supplies. Will not help you during successive lightning hits.

As I experienced almost two years ago. Having a back up system in place, at the ready, is a good investment. The poor folks who live in Lightning Alley, I can only wish them all the best.

I had to live out there for almost 18 months and it was complete hell.

Teken . . .

 

[westom]

One thing to remember in dry areas (like where I live) is that if the ground rod is in dry-as-dust dirt,it won't be very effective in providing an easy path for the 'surge'.

If ground so dry as to not be conductive, then lightning is not striking earth. Yes, moist ground is more conductive. Upgrade an earthing when soils are less conductive. Dry soil is still an electrical conductor.

For most, a few ten foot ground rods are more than sufficient. For others, a larger system is necessary.

Protectors are simple science. Degrade when grossly undersized. Critical numbers for a protector determine its life expectancy. What happens after many surges? If a protector is properly sized, then degradation is so minor as to be considered zero.

Earthing defines protection for each surge. Critical for protection during any one surge is the quality of and connection to earthing. Telco's switching computers suffer about 100 surges with each thunderstorm. Why does your town still have phone service for four days after each storm? Telcos cannot have damage. So telcos worry most about the one thing that makes protectors effective. Earthing. So that even the driest soils conduct electricity harmlessly outside.

Anyone building a new home can plan for protection BEFORE footings are poured. One best solution was pioneered in munitions dumps - Ufer grounds. Builders have many other solutions. For example, if soil is driest, some encircle a building with a ground wire.

Earthing is upgraded so that the electrode remains the best conductor into earth. No matter how dry that ground, a lightning strike is still flowing through earth. Protection is always about making that connection on a path that does not pass inside the house.

Damage is always about a defective earthing system. For example, a case study of damage to a Nebraska radio station was made worse when station engineers failed to learn what defines protection. Damage even from lightning strikes ended when the building was properly earthed. Even the utility's telephone pole ground was upgraded. Because protection without damage is routine when earthing defects are located and eliminated. The case study describes what has been well understood for over 100 years:
http://www.copper.org/applications/electrical/pq/casestudy/nebraska.html

Effective protectors connect surges – even direct lightning strikes – harmlessly to earth. A protector is only as effective as its earth ground.

 

[bud--]

Anyone building a new home can plan for protection BEFORE footings are poured. One best solution was pioneered in munitions dumps - Ufer grounds.

For most new construction the NEC requires a "concrete encased electrode", commonly called a Ufer ground.

As I wrote in my first post, even with a very good earthing system a strong surge will lift the building "ground" far above 'absolute' earth potential Much of the protection is that all wiring rises together. That requires a short ground wire from phone, cable, dish entry protectors to a common connection point on the earthing system. The distance from the service N-G bond to the common connection point also needs to be short. (Covered in the IEEE surge guide.)

When the earthing system has higher resistance to earth, a service panel protector will still limit the voltage from hot wires to neutral=ground, which is all that the protector does. The building "ground" will rise higher above 'absolute' earth potential. There could be problems where equipment has an easy path to earth. One place (which is in the IEEE surge guide) is pad mounted compressor/condenser units.

In general, 70% of the voltage drop away from a ground rod is in the first 3 feet.


Protection from lightning coming in on wiring is not rocket science. People in high lightning areas, like Florida, can effectively protect their equipment.

Effective protectors connect surges – even direct lightning strikes – harmlessly to earth.

As the IEEE surge guide explains for anyone who can read, plug-in protectors do not work primarily by earthing surges. They work by limiting the voltage from each wire (power and signal) to the ground at the protector.

A protector is only as effective as its earth ground.

Westom's mantra protects him from conflicting thoughts (aka reality).

Both the IEEE and NIST surge guides say plug-in protectors are effective

 

[2manytoyz]

This is the surge protector I installed on my last house:

Inside, the circuit board is buried in sand. Great fire suppressor.

There's a bunch of MOVs (red discs) inside, along with other components:

Central FL is the lightning capital of the continental USA. Surges are all too common. If you lived here any amount of time, you've thrown out toasted electronics. For a $100, and an hour's worth of labor, it's a cheap investment. Had zero issues since it was installed.

I moved last October to another house. I just bought another surge protector (same brand, newer version) for this house.

Won't protect against a direct strike, but odds of damage from a surge are far greater.

FWIW, the only power strip I'll use that has surge protection is one that actually has thermal fuses mounted against the MOVs. MOVs get HOT as they fail. If there's no thermal fuse, they can eventually cause a fire. One of the USA embassys burned to the ground, and an MOV was listed as the cause. We had a number of close calls at work.

Here's a powerstrip at a coworker's house. An MOV failed:

I use Tripp-Lite brand power strips. They have a metal housing, and thermal fuses inside.

 

[rlitman]

This is the surge protector I installed on my last house:. . . Here's a powerstrip at a coworker's house. An MOV failed:

I have those exact same TVSS units on my home panels.

We used to have those exact same power strips at a place I worked, except they were labeled APC. Yes, the TVSS's in there are exposed to the air, so if one blows, it'll do just that (but it won't burn your house down in that strip, as it's well contained in a non-combustible plastic, and we'd seen much worse damage caused by arcing in a different brand power strip).

 

[westom]

We used to have those exact same power strips at a place I worked, except they were labeled APC.

Those power strips are the reason for house fires. The internal protector (MOV) is undersized. During a potentially destructive surge, a thermal fuse must disconnect the protector parts. While leaving a surge connected to the appliance.

Sometimes that fuse does not blow fast enough. Then a fire can result. Stories are numerous. For example, Whitneyd88 in "My house caught on fire and my tank busted":

A plug caught fire in my room (which was plugged into a surge protecter) it was caused by a power surge and caused my tank to burst.

Fortunately, water flowing from the busted aquarium put out that fire.

Norma in 2008 in alt.fiftyplus describes the fire threat:

Today, the cable company came to replace a wire. Well the cable man pulled a wire and somehow yanked loose their "ground" wire. The granddaughter on the computer yelled and ran because sparks and smoke were coming from the power surge strip.

Sparks from any protector can cause house fires.

melbourne architect on 20 Apr 2011 posted:

Cheap surge protectors have been known to catch fire (in one case, a Fire Station was burnt out; the red faced fireman later learnt it was due to the cheap surge protector/power strip in the office)

Earth a 'whole house' protector (such as that Intermatic) to make direct lightning strikes irrelevant. It is not perfect. The IEEE Green Book entitled 'Static and Lightning Protection Grounding' says how imperfect:

Lightning cannot be prevented; it can only be intercepted or diverted to a path which will, if well designed and constructed, not result in damage. Even this means is not positive, providing only 99.5-99.9% protection. ...
Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per 30 years ... to one stroke per 6000 years ...

So yes, the Intermatic is not perfect protection. It will only protect 99.5% to 99.9% of the time. Retail sales myths recommend spending tens or 100 times more money on power strips to get an extra 0.2% protection. That power strip protector that was also a fire threat.

A 'whole house' protector is essential so that power strips (thermal fuses that do not work fast enough) do not cause house fires. Meanwhile, a ''whole house' protector also makes that power strip all but completely unnecessary. Upgrade earthing so that a 50,000 amp 'whole house' protector (ie that Intermatic) protects even from direct lightning strikes.

 

[cowboyjosh]

On my house in suburban Denver, I have a LEVITON TVSS on the outdoor feed thru, on the 2 panels in the basement I have 2 Square D QO Secondary Surge Breakers installed; as well as point of use outlets and UPS on the computers and Monster line conditioners on the TV's and home theatre stuff. We too experience more then enough lighting so I went ahead and also had lightning rods installed a couple years ago after having a stike that was a little too close for comfort and after seeing several homes in my neighborhood get struck and had holes blown thru the roof decking from the strike; on one of the houses that got struck and had a hole blown thru the roof the only reason the attic didn't continue to burn was it was raining so hard it put out the fire....Scary ****.

 

[bud--]

Those power strips are the reason for house fires. The internal protector (MOV) is undersized. During a potentially destructive surge, a thermal fuse must disconnect the protector parts. While leaving a surge connected to the appliance.

As westom knows, the thermal fuse is not fast enough and will not open during a surge. It opens after the surge when a failing MOV starts to conduct on normal voltage.

Martzloff, the author of the NIST surge guide, has written "in fact, the major cause of [surge protector] failures is a temporary overvoltage, rather than an unusually large surge." Temporary overvoltage is a far longer event, for instance crossed power wires.

The IEEE surge guide explains the protected load can be connected across the MOVs, and be disconnected with them, or can be connected across the incoming wires. If connected across the MOVs the protected load is not exposed if MOVs fail. Connecting this way is one reason some manufacturers can have protected equipment warranties.

Sometimes that fuse does not blow fast enough. Then a fire can result.

UL has required thermal disconnects for failing MOVs since 1998. A description is provided by 2manytoyz.

Lacking technical arguments that support his opinions that plug-in protectors do not work westom tries fear. Westom has no sources that say that a protector made after 1998 caused a fire, or even that a UL listed protector caused a fire.

Earth a 'whole house' protector (such as that Intermatic) to make direct lightning strikes irrelevant. It is not perfect. The IEEE Green Book entitled 'Static and Lightning Protection Grounding' says how imperfect:

The 99.5% protection figure westom quotes from the Green Book for service panel protectors is actually for lightning rods. Yet another lie.

For real science read the IEEE and NIST surge guides. Both say plug-in protectors are effective.

Based in investigations by Martzloff, a service panel protector is very likely to protect anything connected to only power wires from a very near very strong lightning strike.

And based on Martzloff's investigations, even without a service panel protector, a plug-in protector with high ratings and connected correctly is very likely to protect from a very near very strong lightning strike.

For a direct hit to the building lightning rods are required.

 

[gatchel]

WOW!

You guys (gals if any) really have me thinking. I have wanted to update my ground rods to current standards (2 rods instead of 1) but haven't gotten to it in 10 years of owning the house. The " list " is ever changing if you follow me....


Is it worth while to have say, 3 ground rods newly installed to help with the direction of transients when they occur? What do you think.

I know that ground rod resistance testing, they say, takes 3 rods to measure the resistance so that's where my ground rod guess comes from.

Code only requires 2 as of right now. Any reason why 3 would not help or hurt performance?


Second topic: Are big box ground rods the same quality as the supply house rods or are there different quality copper rods too?...
Thanks

 

[pattenp]

I would think more rods the better but having at least the two would be a good update to do. I've bought ground rods from both the big box store and the electrical supply and they have been the same brand. The big box store was cheaper. Also the copper rods are just copper clad, but I used the copper clad rods over the galvanized rods.

 

[Teken]

I believe what needs to be re-stated is the following regarding this topic. To ensure the highest level of protection. It is essential that the Earth ground at the service entrance / panel be coupled correctly.

Using and deploying, a layered approach with respect to primary, secondary, and point of use surge protection devices is the ideal approach.

In all cases having the ability to unplug a device not in use is the best long term protection for those random use items. Ensuring you are properly insured, to guard against the ultimate disaster is best practices.

Teken . . .