09/06/2001

By DOUG BEDELL / The Dallas Morning News

Perhaps no piece of home computer equipment is more unappreciated than the lowly UPS, or uninterruptible power supply.

UPS units are the garden slugs of the computer world – ugly, ground-dwelling creations with the vital role of keeping systems safe.

"You don't realize its value until you don't have it and you've lost everything," says Mike Delgrosso, software manager for Tripp Lite, maker of some of the more popular consumer UPS systems. "When you buy a UPS and stick it under your desk, you ask yourself, 'Well, what's it really doing for me?' "

What UPS units can do is save a computer and other sensitive household electronic components from certain and slow death. The enemy for all is unpredictable electrical currents coming directly from wall sockets.

UPS products can help ensure that a computer continues to run during a sudden loss of power. They allow a graceful shutdown of open programs, minimizing loss of crucial data.

Modern home office UPS units also filter out damaging interference from other household electronics. Most double as surge suppressors, guarding against lightning strikes that leap through telephone, cable and electrical lines to fry modems, motherboards and hard drives.

Most users are aware of the need for surge protectors, those low-cost strips of plastic sockets that instantly cut off power when wide variations of current are sensed, says John Staples, owner of Computer Junction (www.computerjunction.com) in Richardson and Fort Worth.

"The need for UPS units escapes them," he says.

UPS devices such as those made by Tripp Lite (www.tripplite.com) and APC (www.apcc.com) go beyond standard surge protectors. They add backup battery support to anything plugged in. When a complete power shutdown occurs, the backup battery kicks on within milliseconds, an alarm goes off and the computer user is given valuable minutes in which to move to the keyboard and shut down applications.

Higher-priced UPS home office models have computer connections and come with software that can automatically shut down systems if no one is there to tend them.

UPS boxes were once essential, high-priced pieces of only the largest corporations. Today, affordable, compact UPS units are available for $100 or less with an array of features.

"They're well worth the price," Mr. Staples says.

Current dangers

When a computer suffers that kind of outage, a lockup or freeze can result. The screen may appear unchanged. Sometimes, the cursor can be moved around, but the computer won't respond otherwise.

Brownouts rob computer memory modules of their ability to keep track of what's happening on the desktop. A power interruption of only a 50 billionth of a second can cause RAM chips to suffer amnesia. Data loss can be complete and severe.

Even if a computer seems unaffected after the briefest of episodes, chances are that damage has occurred, Mr. Staples says.

"The heads inside a hard drive ping on the platters, and when they're doing that, they're making that hard drive worse as time goes on," he says. "Eventually, you'll start losing data or the heads get defective and break completely."

That's not to say that surge protectors alone are ineffective. However, unless users are plugging their Internet connections and all peripherals into the surge protector, damage can still occur.

"The majority of our service work still comes in right after a healthy lightning storm," Mr. Staples says. "Users seem to take such precautions to put protection on their computer, but then they put their telephone line directly into the wall.

"That's a prescription for disaster."

New, sub-$200 UPS systems contain inputs for cable, telephone, DSL and other connections to the outside world. Plugging those into the back of a UPS can protect against most kinds of electrical events.

"Most people won't need anything more than a $100 UPS," says F. Lee Pyles of ComPyles Computers in Rowlett. "Some of the worst damage I've had with machines has come from those rapid power outages."

The right UPS

In general, experts say a home computer, 17-inch monitor and modem require about a 500 volt-amp power rating (300 watts). APC and Tripp Lite offer online calculators to help users figure out which of their products is best-suited for their needs. Another calculator is available at SizeMyUPS.com.

Mr. Delgrosso advises consumers not to connect laser and other household printers to UPS units. They sap too much battery life when a complete electrical failure occurs.

Manufacturers report the demand for their products is not growing much beyond the doors of the home office.

APC now includes recommendations for protecting against interruptions to fish tank motors and security systems, which may sound expensive false alarms when power fluctuates.

Home medical equipment can sometimes be kept running on UPS backups, preventing critical shutdowns.

Even computer game players are beginning to use UPS devices.

"Imagine getting so close to winning a game, perhaps replaying the invasion at Normandy or subduing the last dragon, and suddenly the power drops or a fuse is blown," says gamer Tony Charity of Seattle in an APC testimonial. "The hours you put into the game would be lost."

On Internet hobbyist discussion boards, audio-visual equipment enthusiasts report that they, too, are increasingly using uninterruptable power supplies with VCRs and DVD players. Not only does a UPS protect against fatal power glitches, it also keeps users from having to readjust settings and electronic clocks.

Mr. Staples heartily endorses UPS products out of personal experience.

"We had a lightning strike at our house, and it literally took out every piece of electronics we had – including my 5-foot-wide TV," he says.