Use a Surge Protector

If that AC cord coming out of your computer goes directly into a wall socket, you're putting your Mac at the mercy of the power company, your home's wiring, and all the things that can go wrong in between: brownouts, voltage spikes, lightning, you name it. Your Mac's power supply is pretty robust, but a single random power surge can still fry its circuits. Even when the electricity appears to be flowing correctly, imperceptible fluctuations in the current can cause computer components to deteriorate more quickly than normal.

So please, take the basic precaution of using a surge protector. They come in many shapes, sizes, and pricessome with every bell and whistle, and some quite plain. Not all work equally well, so look for a model with a good warranty that covers not only the protector itself but also the equipment attached to it, in the event of a surge.

Better yet, consider buying a small UPS (uninterruptible power supply). A UPS contains a battery with enough juice to power your computer for anywhere from a few minutes to a few hours, along with circuitry to convert the battery's DC output to AC and switch over to the battery instantly and seamlessly in the event of a power outage. If the power goes out for more than a very brief period, the UPS sounds an alarm so that you will know to save your work and shut down your computer safely before the battery goes out. (Some UPS units include software to handle automated shutdowns.) In addition to protecting your computer from power outages, a UPS conditions the electricity flowing through it and absorbs surges.

A Conversation about Surge Protectors and UPSes

Do you really need a surge protector? Is a UPS worth the extra money? The experts weigh in:

Sharon Zardetto Aker: In 20 years of having multiple Macs (there are a half dozen in use in the house right now), 10 years of which was in the country where power came and went with strong breezes, I've never had a surge problem affect any Mac, nor do I know of anyone who has ever had that problem, so I'm a little uncomfortable with this recommendation.

Dan Frakes: Consider yourself lucky! In my humble opinion, no computer should ever be run without a surge protector. All it takes is one incident to make a believer out of you!

Kirk McElhearn: I agree with Dan.

Adam Engst: Personally, I never use surge protectors, but I wouldn't run a Mac without a UPS. Power flickers too often for my taste, and preventing the lost work is worth it.

Tonya Engst: I've found that an important side effect of running a UPS, in addition to allowing a graceful shutdown at the beginning of a power outage, is that I can work on days when the power flickers frequently. In Seattle, probably once a month or more, and here in Ithaca, certainly once every 6 weeks, the power goes out maybe 8 times, for about 20 seconds each time, over the course of an afternoon. Without the UPS, I wouldn't be able to work effectively on those days.

Geoff Duncan: I feel more comfortable recommending a voltage regulator or a power conditioner instead of consumer-level surge protectors, which are usually pretty useless. UPSes are even better.

My favorite UPS manufacturer is APC (American Power Conversion). To find one of their models that suits your needs, use their product selector at Other UPS manufacturers that offer Mac-compatible software include:

  • Belkin (

  • MGE UPS Systems (

  • Xantrex (

Real World Mac Maintenance and Backups. Industrial-Strength Techniques
Real World Mac Maintenance and Backups. Industrial-Strength Techniques
Year: 2004
Pages: 144 © 2008-2017.
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