PC hardware forum: Do surge protectors merely give us a false sense of security?

As mentioned,,,, surge protectors protect from high voltage spikes,,,, or rapid increase in line voltage,,,, say if lightning strikes the power line,,,,, but if lightning strikes anything already grounded,,, like a Telephone pedestal,, that lightning can travel on the Telephone ground or any other Telly bell wire(s) and enter your home,,,,, the surge protector,, is not a part of that recipe,,,,,as a surge protector,,,,, uses the ground to drain off the unwanted voltage, so when it back doors the protector,,,, it just passes through,,, and can energize ALL your grounds or neutrals in the home. Add to that,,,,, you are asking an awful lot of a surge protector to whoa down lightning,,,,,, since lightning can have infinite voltage,,even when it strikes a driven ground rod (s) it is too much for that rod to absorb so it will travel back up the ground wire for an unknown distance to the next ground,, which may be your house,,,,,,,,,,, it is very difficult to drain off all those killiwinkles through a table top protector. So, if you add a bunch of extra ground rods,,,, that seem like it would help,,,, but that can also backfire on you,,,,,, if your ground grid is better than the utility companies in that immediate area, I am retired from the local utility company,,, and believe me,,,, the ground/neutral system pole to pole does go back to the source [Sub station ],,,, but it is only as good as the worst connection, and number of corroded ground rods while it makes that journey. So,,,sure, use a surge protector, it may be a good thing to show the insurance man when you get zapped, and they 'may' help on certain situations,,, but they do not cure all things.



Note: This post was edited by its original author to remove strikeout code that was inadvertently posted in body of text on 07/02/2012 at 2:42 PM PT

Thanks Dana. As the original submitter, I am rating your response "most helpful." Your general recommendations are particularly helpful except that #7 and #10 are redundant, but no doubt that was intentional . And yes, I do backups frequently.

I tend to agree with your conclusion that, based on the pattern of damage, the surge entered through the cable line. It certainly explains why the two modems were fried. The cable tech discovered that the earth ground wire at the cable service box was *not* connected. Now at least that has been fixed.

I was using a UPS for my desktop at the time. It tolerated the lightning surge just fine. So did everything else in the house except the multi-function ("MFC") system. As "duddly" points out the surge may have taken a path through the phone line. But the phone line to the MFC is daisy-chained through my desktop modem card which was not damaged. I didn't lose any other phones in the house. So I am left to conclude that the MFC was simply a weak link or that it provided the best path to ground for a pass-through surge on the phone line (i.e., cable line through phone modem to phone line through MFC through surge protector to ground return).

I am investigating whole house protection. Thanks for suggesting that.

Iimportant fact was that a surge was permitted to go hunting for earth inside the house. Protection always means a surge is earthed BEFORE entering. The cable was not grounded (to the same ground used by AC electric and phone)? Then that was an ideal incoming path. But appparently the most common source of surges (AC electric) also was not earthed. No 'whole house' protector means AC is still not earthed.

If any incoming wire (ie two of the three AC wires) is not grounded low impedance (not low resistance) to the same earth ground, then protection is compromised. Incoming cable must make the same low impedance (ie 'less than 10 foot') connection to the earth also used by phone and AC electric. All must connect that short on a ground wire that has no sharp bends, no splices, and is separated from all other non-grounding wires. Every requirement is critical. Some cable guys never grasp the concept. Cable must be grounded. And must be single point grounded.

Without single point ground and every incoming wire connected low impedance (ie 'less than 10 feet') to it, then a surge is all but invited to go hunting for earth; destructively, via appliances. Nothing inside stops that hunt. But some appliances can act like a 'whole house' protector. Destroyed by a surge that selected those appliances as the best connection to earth.

Portection is not defined by interior solutions. Protection is always about a 'low impedance' connection to earth AND where that energy dissipates.

So did the cable guy make a 'low impedance' connection to a single point ground?

I would just like to add to my previous post that over my many years of servicing computers and electronics, by far, the most damage to computers and other electronics seems to be due to power surges that occur when electrical service is restored and/or during those moments of when the power suddenly goes off and on several times in quick succession. Here in the northeast, this is very common during heavy snow storms or high wind conditions and is totally unrelated to lightning. I have found that the best overall investment is still the UPS (uninterruptable Power Supply) which offers some minor surge protection as well as battery backup thus preventing sudden shutdowns and startups of your sensitive equipment. Protecting against sudden loss of power is especially important for equipment containing hard drives such as computers and DVR's.

NOTE: This is based on my observations and not on any scientific data.

As far as those of you that live in areas of frequent thunderstorms, I would still recommend having the UPS and whole house Surge protections and in addition I would suggest that you have all your ground systems checked to make sure they are in good condition. This includes your electrical service, Phone lines, and Cable TV lines.

I have no opinion regarding the effectiveness of home lightning rods but I do notice that you will always see them scattered about any power substations so I have to assume they did not put them there for no good reason. Maybe someone with knowledge of Lightning rods can comment here but I was always under the impression that one of the main purposes of the lightning rod was to help neutralize large charge differentials via corona discharge to prevent a lightning strike and not to purposely take on a lightning strike. But I could certainly be wrong here.

Dana
Wayland Computer

Any power strip with a surge protector have a dicipation limit. If a single surge is strong enough, it can burn it in one go. Many small surges will also eat away your protection. When the dicipation limit have been exceeded, then the surge protector can no longer offer you it's protection. It becomes a simple power strip. There is NO visible sign of that.
Then, a $20 surge protector is realy LOW end protection, only good in large city where any surge have 1000's of routes to the ground and even more "target".

If you live in an area where violent tunder storns are common, especialy in a rural or sparcely setteled area, like to many suburbs, you probably need to replace them at least once every year.
If, for example, your surge protector is rated 100 000V, 10 000 000 joules, and a lightning bolt strike the power line only 300m away, it may have to cope with 50 000 000+V (FIFTY MILLION volts), 100 000 000 000+ joules (ONE HUNDRED BILLION joules of power) whammy, possibly even more. That's way more powerfull than it can ever hope to dicipate. Such a bolt can arc over more that a Km, like the distance between the ground and the clouds...

Maybe you need to invest into a main power power surge filter that is installed between the electric counter and the electric pannel. Those are based on a different technology and are much more resilient and durable and don't get worn over time, but can't always totaly block some power surges and do cost way more, probably a few $1000's. They also have a much higher power dicipation capability. Then, use regular power surge protection for your electronic equipment. In an area where severe and violent thunder storms are frequent, a $20 solution is similar to a simple, unprotected, power strip. You need something in the line of a $50 (strict minimum) to $80, and maybe more, surge protector.

No surge protector can completely protect you. You say your area is prone to severe thunderstorms and don't mention any previous problems. I'd say there's a fair chance your surge protectors have saved you several times before without you even knowing.

Some years ago we had a computer fried, but had a surge protector connected. The surge didn't touch the protector but damaged the computer. I contacted the company and they paid for my new computer. So it pays to read the fine print.

Maybe today they have changed??????

There are no rules of lightning. Surge protectors help with normal voltage fluctuations that occur with generated power, not lightning strikes. Lightning can strike a house and travel through the ground and come in the back door of a surge suppressor. I worked on a house that had been struck by lightning that had melted the electrical wiring and it never tripped a breaker in the distribution panel. Best advice is to turn off and unplug when there's lightning striking nearby.

But one would expect the legalese to protect the maker.
Seems like false advertising, though.
Check with your state atty general.

I have been using APC BackUPS (current one on my PC is RS 1300) for years on my PC and even TV's and entertainment systems running their individual UPS's just for the sake of those annoying on-off, on-off, dim out-and in cycles during a storm or when the power is ready to go completely out, with good success so far.
However, APC and even TrippLite UPS unit instruction warn about hooking up (first a Laser printer) and second a SURGE SUPPRESSOR type power strips to their battery backup AC outlets, since most UPS units do not always have a true sinesuidal waveform output such as the power mains, but a rather 'squarish' waveform which the UPS will not tolerate in having a surge suppressor type strip connected to it under power inverter mode.
Both telephone line and cable coax lines are also connected to my APC 1300, even though I do not use a phone modem on my PC, just an extension phone by the computer, but the line running to my DVR does have the phone line connected to it through the UPS. Some APC models will have an ethernet connection surge suppressor feedthrough, mine has the actual cable coax in and out to the cable modem, and of course the modem power supply transformer is in the APC powerstrip for the AC.
I am still wondering however, since no one really mentioned this, that most of today's cable services and telephone services are tied together such as XFINITY COMCAST and VERIZON FIOS, and they all claim that FIBEROPTICS come right up to the house, and only inside is it converted to coax and telephone mini plugs for conventional equipment ... so as long as that conversion box is grounded and/or disconnected from the AC source I do not see how fiberoptics would be effected at all by lightning surges.
Unfortunately, my landline phone is still via the old system (box outside the condo with 4 wires and is grounded to a copper rod, along with my cable coax feed also using a grounding block with a wire to a grounding rod) before entering the house.
This business about disconnecting everything that is plugged in, is rather unrealistic in my opinion, because the storm would be over by the time I would get to everything in the house to unplug or move furniture to get to outlets, not even mentioning what do you do with a central A/C, electric range/oven/dryer or dishwasher that is 'permanently' wired in to 220VAC or unmovable. I would think if one would just throw off ALL BREAKERS in the electric panel, individual and MASTER breaker, it would suffice to protect everything unless the house gets a direct hit, in which case I doubt if anything, even good grounding would help.

Get a lightning rod for you house. It will protect from direct lightning strikes, but won't help with line surges. I turn my stuff off during storms regardless of having surge protectors.

As I Master Electrician I have to concur with the editor that there is really nothing you can do against actual lightning. Surge protection guards against power line surges and iregularities from the utility service and other power sources. That power is generated within a certain tolerance. Lighning, as a force of nature, is totally unrestrained. As I'm sure you are aware, lightning has been responsible for blowing trees apart and I have witnessed brick chimneys blown apart.

If anyone thinks a simply piece of electronic circuitry is going to stop raw lightning, I will sell you all you can afford. Unfortunately I will only give you the warranty of the equipment manufacturer, which does not cover lightning.

I have witnessed the result of lightning hitting the center of a cul-de-sac and blowing out electronics in every house in the court. It entered every avenue available, not only the utilty power.

It is wise to protect your equipment from utility surges with anything available, just as it is wise to back up your data, but be aware that electronics (and many other forms of matter) in the vicinity of a lightning strike do not have to be connected to anything to be destroyed.

K.A. Myers
KAM Power

I'm not a master electrician nor have a degree in electrical engineering. Lets do a little common sense look through. Think about the following.

The lightning bolt has jumped from cloud to ground or vice versa, at a distance of approximately 1/2 to 1 mile in distance. Most lightning bolts are at least several hundred thousand volts to over a million volts.

The distance between ends of an open fuse or tripped circuit breakers are 1 inch or less. Does anyone think this infinitesimally small gap will make any difference to something that has jumped about 1 mile?????? If you do I have a refrigerator, freezer franchise up for bids at the Arctic Circle! Even if you go to the fuse box and open the main breaker your still at risk!

Your best bet is to completely and I do mean completely, totally disconnect everything from any and all external connections. Be it power cords, phone lines, etc. Even then, "hypothetically", you could still suffer damage to your equipment from EMP if the strike were close enough. The pulse could induce current/ voltage due to transformers/ coils in the equipment and cause damage. A little over the edge yet still within the probability factor!

A little over 20 years ago I, along with about 5 homes in my area, lost just about everything in our homes. Living out in the country we were within 1/2 mile of each other. We had a very close strike in our area. The storm was so violent that the aluminum siding on my home was actually cracking, I think acting much like a capacitor charging up. When the flash and bang, which happened virtually at the same exact time, my home electronics were destroyed, TV, cable box, well pump, fish tank filters, etc., etc. I had even disconnected the cable from the cable box yet you could see where it arced across the approximate 12 inch distance from the box to the cable, burn mark on the corner of the box!

After the storm had passed, comparing notes with my 5 neighbors all had suffered the same damages! Now do I have suppressors/ UPC's etal? Yes! Do I believe in them 100%? Emphatically NO! Do they help?? Maybe! BUT a near direct strike lightning bolt is in all probability going to get you! How much damage you incur is at best up to God! Regardless of what protection you think you have!

I had always thought that there would be really very few claims submitted to APC and that they would make good on them. This is after all simply a financial insurance policy. You pay $20 (+/-) premium, one in 1,000 submit a claim for like $200(+/-) , APC pays the benefit. Looks like I was wrong. I hope APC's marketing people read this and adjust their responses.

And when was the last time you backed up your data. Replacing a piece of equipment (whether paid for by a surge protection vendor or not) is easy compared to replacing your data.

An if you backup to an external hard disk, disconnect the data cable and the power cable when the backup is complete!

Good surge protection will protect against utility power surges and are covered under warranty. A UPS also helps moderate those surges and allows you to shut down equipment in an appropriate manner if there is too much threat from MODERATE lightning induced surges.