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Discussion Starter · #1 ·
This is a topic that generates great debates in many venues regarding the value and necessity of surge suppressors and line conditioners. Let's not start that debate in this thread. I start with the assumption that in many areas SS can be a big benefit for several reasons.

With that as the starting point, the obvious question that this begs is "what should I use?" With that in mind, I issue a challenge. With a little research I find the Tripplite HT1010SAT3 which can be found for about $45. Can anyone find a better value, in terms of protection and functionality?

Just to be clear, this is not a product that we sell, nor am I trying to promote any particular product. Just trying to research the best value.
 

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Not me.

On the other forums I've frequented, Tripplite has always been the clear favorite. Good product for relatively low $$.

JCD
 

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I have also read good reports on the Tripplite line of products. I know on some models they have suppression between each of the outlets. This means that every piece of equipment plugged into the unit is isolated from each other as well as from the power line. This is important since some equipment, especially those with electric motors, can cause corruption on the power line.

I own an Isobar IB-8, and it seems to perform well. Belkin makes a similar line of suppressors. One thing to keep in mind is that almost all suppressors use MOV's to suppress transient voltages. While these work very well they have memory. So the more transients they suppress the less effective they become. Some high quality industrial grade suppressors use other means for suppression, but they are very expensive.
 

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I use a ZeroSurge unit. One of these days I'll get a UPS but for now I have the 20 amp model.
 

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Discussion Starter · #5 ·
While the concept of filtering surges (Zero Surge, BrickWall, etc.) as opposed to current dumping(using MOVs) has great merit, it is not the complete solution that ZS would suggest, and some of the conclusions and statements on their web site are misleading and incorrect. For instance, they say that "only normal mode surges enter buildings" and base this on the assumption that because the ground and neutral are bonded together at the building service entrance that no voltage can exist on the ground or neutral side. This is a large and faulty assumption and the conclusion that three-way or all-mode protection is not required is, IMO, faulty. It is not uncommon for the ground to go high in a nearby lightning strike, even when grounding is proper. In these cases, having MOVs to dump current back to the normally "hot" side may be a big benefit.

Inductor/filter based devices are quite useful, but only up to the limits of their capacity. Large capacity units are relatively expensive. The advantage to MOVs is that they are cheap and dump current to whichever side is low when the voltage across them is exceeded. They may lose effectiveness with repleated use, but the amount of energy needed to degrade them is not typical of frequent surges.

The other limitation of the ZS and other massive filter based devices (and with most whole house suppressors) is that they typically ignore other signal lines into the system such as cable, sat, line level audio, phone, and network lines. Having protection on these can be important, and having local single point grounds can alieviate interference and gournd loop problems. I see enough damage from ground (i.e. common mode) surges that is catastrophic that IMO it is an important aspect of surge suppression.

Ideally, a large capacity inductor based unit followed by a more typical MOV based product with signal line protection would be ideal, but perhaps overkill. The Tripplite unit that I posed as a reference to make comparisons to seems to have reasonable protection for a low price, though there have been some reports of signal loss in the coax lines. I suspect that those are due to poorly made connections, since the bandpass specs that I have seen for them are typically more than adequate. I'll order one and check it out. My challenge still stands to find a better value...either something close in price that offers similar or better protection and features, or something cheaper that does the same.

Most important to remember is that one MUST have good grounding where all incoming lines are grounded to the electrical service ground electrode at the entry point to the home or no type of surge suppression will be as effective as it could be. I recommend checking your grounds at least once a year for corrosion and to verify that they are tight. Don't let cable or sat installers get away with not grounding your system properly. They must do it according to code and your local county inspectors will force them to do so if they refuse.
 

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I am sure you are more up on this subject than I am, but I just read an article by Dr. Craig Hillman (who ever he is) and he states:

"Electrical stress applied to a ZnO MOV for longer than a few microseconds causes chemical changes at its grain boundaries, causing their diode-like characteristics to become more ohmic (diodes become resistors).
-- MOV turn-on voltage decreases.
-- MOV leakage current increases."

Of course he doesn't define what "electrical stress" is, but I would think that a hit from a lightning bolt may qualify.
 

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Or age. Even low power spikes over a period of time will damage or destroy the MOV's, and since the power lines fluctuate widely every day it is a problem that you need to watch out for.
 

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Discussion Starter · #8 ·
reed.hannebaum said:
I am sure you are more up on this subject than I am, but I just read an article by Dr. Craig Hillman (who ever he is) and he states:

"Electrical stress applied to a ZnO MOV for longer than a few microseconds causes chemical changes at its grain boundaries, causing their diode-like characteristics to become more ohmic (diodes become resistors).
-- MOV turn-on voltage decreases.
-- MOV leakage current increases."

Of course he doesn't define what "electrical stress" is, but I would think that a hit from a lightning bolt may qualify.
This needs to be kept in context. Even Sero Surge's own web site shows that the rating for the larger MOVs of three of the major suppliers are rated for 100 surges of 1000 amps. Most systems will never seen any surges of this much current, much less 100. Even here in north central Florida, where we average many times the lightning strikes that other parts of the US have, we do not see MOVs failing in surge suppressors other than in extremely close lightning strikes.

When they fail, they tend to short and blow circuit breakers and the failure is obvious. It should also be noted that repeated excessive voltages on any semiconductor junction will cause similar degradation. Also, increasing of the leakage current on a varistor is minimal. If it gets very high at all, it will usually break down and short. The better vendors will simply replace a surge suppressor that fails.

Yes, it should be understood that MOVs are sacrificial devices. It should also be understood that filter based series suppression systems are more costly and power ratings are much more important to consider. There are pros and cons to both types of systems.
 

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Discussion Starter · #9 ·
Danny said:
Or age. Even low power spikes over a period of time will damage or destroy the MOV's, and since the power lines fluctuate widely every day it is a problem that you need to watch out for.
This is simply not true. It takes high currents to significantly affect the reliablity of MOVs. Most frequent spikes are not very high in current nor duration. If what you say was true, we would be seeing them fail much more often in the many devices that use them (not just SS). I have been working for dealers that have been selling MOV based units in high lightning areas for over two decades and we rarely see bad ones. In severe strikes, yes they do fail occassionally. I have pulse tested quite a few from used units out of curiosity and found the clamping voltage pretty much right where it should be.

Sony used them in several places in TV power supplies for years and while may techs subscribe to the myth that they should be routinely replaced, I have very seldom found one that tested bad without other significant damage to the power supply from surges or other component failures. In fact, they are much more reliable than the other PS components. The problem is that most people have no clue how to test them and other than verifying where they start to clamp, other testing can be destructive. If you understand how they work, however, you know that you can be confident that it will work if it starts to clamp where it should, even if it breaks down. Then you know that it needs to be replaced because they short.

There are certainly advantages to series mode, filter-basd systems over MOVs. The point is that MOVs are a very reliable and cost effective method of surge protection. Once again, you have to keep the information in context. The people selling series units will make you believe that MOVs are bad. It is simply not true. It is also true that they have limitations.
 

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Discussion Starter · #10 ·
Now back to my original question. Can anyone find a more cost effective unit than the Tripplite that I found?

Without spending at least four times as much I have not seen a series/filter-based unit that has the power handling for a serious system, nor that has protection for the incoming signal lines other than the a.c. I'd love to find one, but the fact is, big inductors are expensive, and this technology is not applicable to signal lines.
 

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Icaillo,

Having lost my Denon AVR 3802 to a lightening strike, I was forced into researching this particular topic. I have no in-depth knowledge of individual electrical components so was forced to rely on manufacturers specs and reviews where they exist. Surge protectors don't seem to attract many reviews, but when a product claims an element of filtering/noise suppression as well, then the AV world is suddenly all over it like a rash.

On this basis and knowing that I wanted something with a decent current capacity (Receiver, Phono stage, turntable, TV, DVD, Satellite and large sub) I settled on the Monster HTS 1000. Now it's not as cheap as the HT1010SAT3 but then a) you can't get that over here and b) I thought it good VALUE, which is subjective. It's build is certainly a cut above and it certainly gives me confidence however unfounded that may be. What swung it for me, aside from the build quality, is it has a properly shielded mains lead, signal lead protection and the grouping of certain components to optimise filtering seemed to be favourably reported on and sensible in theory.

As to some of the sound and picture improvements claimed and reported, I think they may be slightly overstated. Although, if push came to shove, I would say the my system is slightly less prone to sibilance now. But no more so than the difference you get by listening late at night when the mains are cleaner anyway.

It appears to use more than just MOVs, but as to what, I'll let you decide. It doesn't satisfy your criteria on price, I know, but with your obvious knowledge on the subject, I'd be interested to hear your opinions.

Russell
 

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Discussion Starter · #12 ·
The Monster products are fine in my opinion, but even though we sell them, I don't believe they are the best value for most people. The HTS 1000 MKII is, I agree, nicely built, but for the price I would likely pick the Panamax M8HC-PRO. While the Panamax does not have as high a Joule rating, they do provide much more detail on the performance of the unit and it has the over/under protection that the HTS 100 MKII does not. It concerns me that MC does not publish much detail such as the peak current ratings. MC seems to be more concerned with appearance and filtering, IMO. While filtering can be a benefit in some limited instances, most performance improvements that have been claimed are, as you said, likely optimistic. My view of filtering and line conditioning is that they should be used when there is a problem that cannot be fixed at the source, but are not assumed to be needed.

Nothing at all wrong with your choice, but the Tripplite can be had for a little more than half of either the Panamax or the MC and has a higher joule rating than either. I chose it for my challenge because of the good basic protection at a low price, without a lot of filter hype. Again, I am not promoting it, we sell the Panamax and MC units.

The above 3 brands, along with some of the Belkin peoducts, are some of the better surge suppression products I have found. I tend to not prioritize the noise reduction capabilities and lean toward the series/filter type units if that is really needed or desired. If I had a problem with noise, I would use a combination of the SeroSurge 2R15W and the Tripplite unit. The two could be found online for about $200. I should probably start another thread on noise suppression on a.c. lines. The need for it is very much overstated, IMO. Ironically, most of the benefits come in with audio systems, not video, which seems to be the focus of so much of the hype these days.
 

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Discussion Starter · #14 ·
It depends on what you mean by small. The ratings that you see in specs for durability in the hundreds of surges are in the order of 1000 amps. I would not expect most systems to see very many surges of this nature in a lifetime.
 

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There seems to be a lot of mixed signals on this topic.

According to Kenneth Brown, chairman of the Technical Committee at NEMA 5-VS Low Voltage Surge Protective Devices: “If MOVs are used within their well-defined specifications, degradation due to the environment is not likely. However, the environment that MOVs are used in is not well-defined. Low voltage ac mains are subject to lightning strikes, switching transients, voltage swells/sags, and temporary overvoltages (TOVs), and other similar disturbances. Due to the variety of disturbances that MOVs are exposed to, degradation or failure are possible in many applications.”

Also, according to Sensors Magazine: “Not all lightning is created equal. About 30% of all lightning strikes have a peak current of over 10 kA, while about 10% of all lightning strikes have a destructive current of over 50 kA (yes, that exceeds the rating of the protector you just bought!) A percent or two of strikes get over 100 kA! Strikes have even been recorded with current peaks well over 200 kA!”

However the above quote needs to be taken with a grain of salt. Due to a variety of factors, the current actually induced into a power line from lightning can be considerably less than these figures.
 

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Discussion Starter · #16 ·
The reason that there are mixed signals is that the actual energy that needs to be dissipated, the time that it takes to dissipate, the paths that the current takes, and therefor the actual current that is experienced at any point in a system is so variable that it is hard to generalize. Every lightning strike affects not only the immediate property upon which it falls, but dozens nearby. Any one of many homes might see a 50kA surge or anything down to zero. Because grounding effectiveness varies so much the way in which the energy is dissipated is very much unpredictable.

As with most issues in the field of consumer electronics, one must combine reasonable analysis, theory, and field experience to come to conclusions that have the highest probability of being correct. Testing and theory tell us that MOVs can degrade with repeated operation. Field experience does not demonstrate large numbers of failures of MOVs, nor of devices connected to quality surge suppressors that use them.
 

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Personally, I prefer the whole house surge protector if it suits your situation and pocketbook, although I do like the Tripplite for local protection . Seems everything you buy today has some electronic control device inside.

The whole house surge protector mounts at your AC service panel. These are typically in the $100 range, and are quite effective. In addition you get the added benefit of protecting the other equipment in your home too.

There are a couple of types. The circuit breaker type that plug in like any other circuit breaker would into your panel. These of course have to be made by the company that makes your loadcenter (Seimens, SquareD etc). There are also generic standalone types (obtainable from Home Depot, etc) that mount on the service panel backboard and are wired into the service panel. These have the advantage of not having to search out the exact breaker type.

Standalone generic units also have a couple phone and cable and DSS surge protectors included on the box. Kind of handy, since lightning doesn't discriminate between the AC line, cable or telephone electrical path when it strikes. In fact, any protection in your home is second order at best since a true lightning strike in your yard develops mega-joules of energy, and there's no hiding from it. That's thousands times the best surge protectors that might absorb 2000 joules. The odds of direct lightning strikes are low, so the more reasonable spikes can best be shunted at the service panel where they enter.

An advantage of the breaker panel type whole house surge protector is that they usually provide a tell-tale set of breakers on the unit itself which trip when the MOV protection is compromised. This convenience alerts you by shutting down your equipment (or any high use circuit) that's connected to one of these breakers, rather than periodically checking the service panel breaker lights - not something anyone is likely to do. Each leg of the service panel is breakered with a tell-tale, so if you have a couple dedicated circuits (that you keep on the same leg), you could simply use one tell-tale to alert you.

I've installed a Siemans whole house protector on my system, but I also use some inexpensive local surge protection also at my equipment. The units I use there provide more MOV protection and some RFI filtering.

You might think that the whole house solution is bit pricey since the unit requires complete replacement when the MOVs are depleted. Personally, I think it's fairly cheap insurance considering the value of your electronic devices in a home. I completely agree with Leonard regarding the overstated notion that MOV's tend to deplete quickly. They're quite robust and many surge protector devices provide a convenient light to alert you to the MOV's health.

Here's a pic I had of my surge protector with the panel off.





brucek
 

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Discussion Starter · #18 ·
I was going to post a similar challenge for whole hose units, but since you brought it up here, the best value that I have found so far is the Intermatic IG1240RC. It appears to have better protection and can be found for about $75, where the lowest price that I have found for the Siemens is $139.

Whole house units do not have signal line protection. The manufacturers like Siemens know that the best place to put suppression on signal lines is near the ground, which MUST be at the service entrance to the home, not the panel. They make discrete units for this purpose. Since the only place to connect an a.c. whole house unit is in the panel, they have to be there.

Nothing at all wrong with whole house suppression, but don't forget the signal lines, as you said. And most important, don't forget to verify the grounding.
 

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The Intermatic IG1240RC looks to be quite a capable device at a very reasonable price. An outfit called A+ Supply Co. is selling them for $55.95; http://www.aplussupply.com/intermatic/pg5000/ig1240.htm.

The Intermatic unit is listed as UL 1449 2nd Edition compliant. From what I have read, this is both a safety and a performance standard incorporating both ANSI & IEEE testing proceedures. This also appears to be the de-facto standard for the suppressor industry.
 

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Discussion Starter · #20 ·
Thanks for the link. That is the best price that I have seen for this one.

I see that they offer the IG1300-2T, that incorporates phone and coax protection, so I stand corrected regarding my comments that the major manufacturers do not offer whole house suprressors with signal line protection. I am surprised to see this, because as a practical matter it is very unlikley for entry points to be in proximity to the panel. It would be a bad idea to route the signal lines to the panel just for this in most cases. Since the grounding on the signal lines MUST be at the entry point, the addition at the panel is only marginally better than proteciton at the system. Also, protection at the AV system that integrates all signal lines reduces the possibility of ground loops. IMO the best protection is to have a whole house suppressor for a.c. at the panel and individual system protection as well. Protectors at the entry point for cable, phone, sat, etc, won't hurt either, but good grounding is most important.
 
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