Surge protector information

Why do I need a surge protector for my computers and what should I look for when buying one?

We need surge protectors to keep all the little circuits inside our computers safe from excess voltage peaks. When these power peaks (surges / spikes) occur, it causes the electrical circuit to heat up—kind of like the filament in a light bulb. Although a big surge can cause the circuit to blow on the spot, lesser surges can peck away at it, eventually causing it to fail.

Sometimes these failures are intermittent, causing your computer to do strange and unexpected things. You know, odd lockups, sudden reboots after it warms up, conjuring up lost spirits—that sort of thing.

Most of the time these oddities are not predictable (since they’re intermittent and all), and show no type of pattern. That said, if your computer is acting weird, it’s not automatically a damaged circuit—don’t underestimate Microsoft’s ability to make strange things happen in Windows.

Now, a lot of people think that most of the problems come from thunderstorms—you know, when lightening zaps a power line. Although a good hit can certainly ruin your computer’s day, there are other more common sources of surges you need to be aware of.

Most of these sources are high powered appliances—refrigerators, air conditioners, furnaces, even hair dryers and vacuums. In addition to appliances, those big power transformers you see hanging off electrical poles can cause problems—especially on hot days when the local air conditioning is giving them a workout.

Any one of the above can cause a disruption in the power flow of your house, creating a surge. It may not be as dramatic as lightening, but can cause damage over time.

What To Look For:


When you buy a surge protector, try to find something better than the $5 or $10 power strip things. Although they are slightly better than nothing, they are notoriously unreliable and most won’t tell you when they are no longer protecting your equipment. One good surge and your protection is gone—but they continue to function as a power strip. Very tricky…

Also, when looking for a surge protector, look for one that features a phone line “pass through”. Telephone wires can deliver a potent surge into your computer. I’ve repaired (and seen) more than a few computers that were damaged due to telephone line power surges.

In fact, phone line surges are more likely to cause damage than power line surges. Why? Your computer’s power supply acts as a built in surge protector (not a great one, mind you). Even if a surge sneaks through your regular surge protector, the power supply may prevent it from doing any damage.

That said, just because your power supply does some remedial surge protection, it’s no substitute for the real thing. Computers get damaged on a daily basis due to lack of surge protection. But I digress…

Back to surge protectors.

A good quality surge suppressor will cost anywhere from $20.00 to $100.00 and be “UL” listed. It should also feature an indicator light that tells you when the surge protection circuit is no longer functioning.

Now, when you start talking surge protection, you sometimes run across folks babbling about clamping voltages, response nanoseconds, and joule levels. Although that is a valid way to compare various surge protectors (and make the speaker look knowledgeable), not every protector gives you that info—and who’s to say it’s even accurate? Let’s look at the “down and dirty” method of finding a good surge protector.

The easiest way to tell if you’re getting a quality surge protector is to look at the “connected equipment” warranty. I like the ones that cover connected equipment for up to $15,000 or more. I figure it they are willing to risk 15K +, they’re probably selling a good piece of equipment. If it doesn’t have a connected equipment warranty, set it back on the shelf and keep a-walkin’

Sure, it’s not as geeky as going into a computer store reciting clamping voltage figures, but for most people it will be every bit as effective.

~ Steve

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.