A lot of people have their computers and other electronics into devices they think are surge protectors. Often, they're just glorified extension cords. I recently had a power surge fry my cable box while sparing other devices plugged into the same strip. While I had a real surge protector, it wasn't exactly the highest quality. Sadly, I knew this and ignored it. Fortunately, the cable company swapped out my box with no questions asked.

Howstuffworks has some tips for surge protector buyers:

On a listed surge protector, you should find a couple of ratings. Look for:

• Clamping voltage - This tells you what voltage will cause the MOVs to conduct electricity to the ground line. A lower clamping voltage indicates better protection. There are three levels of protection in the UL rating -- 330 V, 400 V and 500 V. Generally, a clamping voltage more than 400 V is too high.

• Energy absorption/dissipation - This rating, given in joules, tells you how much energy the surge protector can absorb before it fails. A higher number indicates greater protection. Look for a protector that is at least rated at 200 to 400 joules. For better protection, look for a rating of 600 joules or more.

• Response time - Surge protectors don't kick in immediately; there is a very slight delay as they respond to the power surge. A longer response time tells you that your computer (or other equipment) will be exposed to the surge for a greater amount of time. Look for a surge protector that responds in less than one nanosecond.

I might add that, while it is important to check the stats of these things, it's even more important not to get sucked into the outrageous claims and high prices of the product your local home electronics salesman will try to sell you. They often look very fancy, but seldom match your needs.

• How Surge Protectors Work
  
• Dangers Of Cheap Surge Protectors - scroll down the page
• APC SurgeArrest 11 Outlet SurgeArrest - reputable brand, excellent specs, 11 outlets, long cord, $20

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