Protecting Your Valuable Electronics from Power Surges

I was working with a client recently who was replacing the item shown above — what her computer used to be plugged into — with a decent surge protector. But even her new surge protector may not be providing the protection she thinks she's getting — something I just learned thanks to David Douthitt, who got me reading Power, Surge Protection, PCs, and You by Jeff Atwood.

That article made me want to learn more, so I went on to read what This Old House and How Stuff Works had to say. Now I'm beginning to understand this subject, and I'm looking at what changes I may want to make to my own home, and suggest to clients.

I've always had my computer and my stereo equipment on a surge protector — and it's a good thing, because I've had one go dead after it protected my computer. (Another lesson: Have a spare surge protector on hand, so if one goes out, you can replace it and keep using your equipment, even if the stores are closed.) I added a surge protector to a lamp that proved to be especially susceptible to surges, after paying for repairs a couple times. And when I stayed with friends in Paris, I bought a surge protector to use while charging my iPhone and iPad.

But here are some things I either never thought about, or forgot.




1. It's not just the computer and the home theater you might want to protect.

As This Old House explains, lots of expensive electronics that you might not think about can be hurt by power spikes or surges: that Sub-Zero refrigerator, for example.



Photo from Lowe's.

2. Surges can be caused by things inside our homes.

This Old House explains that surges can be caused by "cycling on and off of laser printers, electric dryers, air conditioners, refrigerators, and other energy-sucking devices in the home."

How Stuff Works elaborates, noting that while people worry about lightning, "A more common cause of power surges is the operation of high-power electrical devices, such as elevators, air conditioners and refrigerators. These high-powered pieces of equipment require a lot of energy to switch on and turn off components like compressors and motors. This switching creates sudden, brief demands for power, which upset the steady voltage flow in the electrical system. While these surges are nowhere near the intensity of a lightning surge, they can be severe enough to damage components, immediately or gradually."

3. Not all surge damage is immediately obvious.

See that part about gradually in the prior item?

Here's what This Old House says: "The damage inflicted by these minor power fluctuations can be instantaneous — but may not show up for some time. 'You might not even notice it,' says Andy Ligor, a consultant with A.M.I. Systems Inc., a firm that installs both residential and commercial surge-protection systems. 'Then a year or so later your microwave stops working.'"

And Surgeassure, another company providing surge protection, says: "Surges are caused most often from utility disturbances and internally generated surges. It is common for homeowners to lose equipment due to surge damage and not even realize it. Many 'mysterious' computer problems such as contaminated or irretrievable files are actually due to electrical surges. Also, breakdowns and replacements of electronic equipment due to what you think of as 'normal' wear and tear may actually be due to internally or externally caused surges."

It's not just surge protection vendors who say this, either. Here's Jeff Atwood, quoting Dan's Data: "Spikes are the real nasties. A spike is a brief increase in the supply voltage — less than 2.5 seconds, often a lot less. For a fraction of a second, a spike can easily subject your equipment to several hundred volts. If this doesn't blow something up outright, it can progressively damage power supply and other components. So, after a few (or a few hundred) more spikes and surges, your PC dies, for no obvious reason. You may lose a power supply or modem; you may lose your motherboard; you may even lose your hard drive and everything on it."



Photo by Jerry / ww_whist, found on Flickr, licensed through Creative Commons.

4. Phone and cable lines matter, too.

As This Old House says: "A surge will follow any wire into a house — phone and cable lines included — and threaten fax and answering machines, televisions, satellite systems, computers, and modems."

And How Stuff Works elaborates: "Even if you connect surge protectors to all of your outlets, your equipment might be exposed to damaging surges from other sources. Telephone and cable lines can also conduct high voltage — for full protection, you should also guard against surges from your telephone or cable lines. ... If your computer is connected to the phone lines via a modem, you should get a surge protector that has a phone-line input jack. If you have a coaxial cable line hooked up to expensive equipment, consider a cable surge protector. Surges on these lines can do just as much damage as surges over power lines."




5. The best protection comes from using a whole-house system plus those individual protectors we're used to using.

I'd forgotten about whole-house systems until I was chatting with website developer Kevin Henney yesterday, who mentioned them to me. And then I remembered that I'd heard about them before from the folks at Positive Electric, who seem to use the Surgeassure products. That picture above is the company's illustration of a breaker panel surge protector.

As This Old House says: "Guarding against surges requires a two-pronged approach: a whole-house suppressor to tame the big, dangerous power spikes and an individual circuit (or 'plug-in') surge suppressor for vulnerable appliances and electronic devices. ... By themselves, whole-house suppressors can't stop surges completely; up to 15 percent of excess voltage may leak by. That's where 'plug-in' surge protectors come in."




6. It pays to invest in good surge protectors.

I'll let you read This Old House yourself to get the ratings to look for. But here's something it's easy to overlook, as explained by State Farm: "Select a point-of-use surge protector that has an indicating light and/or audible alarm to show when it needs a replacement."

Note that the indicator light mentioned is not the same as a simple "power on" light; the surge protector might still power on and serve as a basic power strip even if the surge protection components have burned out. The Tripp Lite ISOBAR Ultra series are what Atwood recommends.

You can also get a UPS — an uninterruptible power supply; some of these include surge protection. How Stuff Works suggests that a basic UPS, just by itself, is probably not the way to go: "An ordinary UPS WILL give you a high level of protection, but you should still use a surge protector. A UPS will stop most surges from reaching your computer, but it will probably suffer severe damage itself. It's a good idea to use a basic surge protector, if just to save your UPS."

Update: Note that some say plugging a UPS into a surge protector is a bad idea.