Rolling blackouts bring the blues to the unwary


January 31, 1994|By MICHAEL J. HIMOWITZ

When the talk turns to blackouts and brownouts, most of us think of the sultry days of July and August. That's when hot weather, thunderstorms and heavy demand play havoc with the electric power system.

But in the Northeast, the winter of '94 has made summertime look like a power picnic. Across the region, snow, ice and freezing rain have snapped power lines, creating local blackouts that have taken hours or sometimes days to restore.

When the temperature dropped below zero and never rose much above it for a few days this month, the 11 electric companies that provide power for a sizable chunk of the mid-Atlantic states ran low on juice and started pulling the plug.

Utility officials, masters of euphemism, called the procedure "rotating outages." In the press, we preferred the term "rolling blackouts." Either way, it meant that a computer program in the utility headquarters cut the power to blocks of residential and business customers for 15 minutes at a time -- bringing electric consumption down to a level that the utilities could manage.

While the outages kept the overtaxed power grid from collapsing into a general blackout, they posed a serious threat to businesses and individuals who depend on computers -- especially systems running without protection.

If the electricity goes out and comes back with a surge -- which it often does -- the sudden voltage spike can fry the delicate circuitry inside your computer. While this is annoying and possibly costly, the only loss is hardware, which can always be replaced.

Real disaster can strike if the electricity goes off while your computer is writing information to your hard disk. Your files may be corrupted or your entire disk scrambled beyond recovery. This is potentially a far more serious problem, one that can threaten the existence of a business that depends on computers for billing, customer records and other critical information.

Luckily, you can protect yourself against most power disasters with a relatively small investment in two pieces of hardware -- an uninterruptible power supply and a tape backup. If you rely on your computers and the data they manage, these items are indispensable. If you don't have them, you're asking for trouble.

The uninterruptible power supply (UPS) keeps power failures from turning into computer failures. The unit, often no larger than a shoe box, plugs into a wall outlet. Your computer, or other critical equipment, plugs into the UPS.

When the power goes

When power is flowing, the UPS filters it and flattens out surges and spikes that can occur when heavy machinery, refrigerators or other heavy-duty electrical equipment switch on and off. Commercial buildings are more susceptible to this kind of problem than are homes.

But the UPS really earns its keep when the power goes off. It contains a battery backup that switches on instantaneously and keeps your equipment running long enough for an orderly shutdown.

Small UPS units that can power a single PC for 5 to 15 minutes are available for $100 to $150. Larger units, which can back up several PCs, a file server, network hubs, minicomputers and other equipment, cost considerably more -- anywhere from $300 to $2,000. The cost depends on how much power you need and how long you need it.

The most sophisticated units can be connected to controller cards in a computer that will notify a network manager when there's a power failure, or even dial a phone number with a warning message.

In buying a UPS, make sure to get enough battery power to handle the equipment you plan to plug into it. If you're in doubt, contact the manufacturer, describe your system and ask for the proper power supply.

We've had UPS units hooked up to the terminals in our office for about a year now, and they've saved us plenty of time and trouble during transitory blackouts. They're definitely worth the money.

Buying a backup

Tape backup systems protect against losing all but the most recent data in disk crashes caused by blackouts or other sinister forces.

There's nothing new about the wisdom of backups. But the traditional method -- copying data to floppy disks -- is virtually impossible in an age of 300-megabyte hard drives chock full of bulky programs and huge data files.

Tape units, now affordable enough for even casual users, make unattended backups of selected files or entire hard disk drives, usually on quarter-inch tape cartridges about the size of a cigarette pack.

Low-end internal tape drives that can store as many as 250 megabytes of data on a single cartridge are available for less than $200. Higher-capacity units with high-speed controllers -- commonly used for network file servers -- can run as high as $1,500. For use in most homes and small businesses, the inexpensive models will do.

If you have more than one computer, consider an external unit that connects to the PC's parallel port. At $350 or so, these are more expensive than low-end internal tape drives and aren't quite as fast, but their portability can make them a bargain.

The backup process takes from a few minutes to a couple of hours, depending on the size of the hard disk and how much of it jTC you want to store on tape. Many users start the tape drive running when they leave work or retire for the night. The backup is ready in the morning.

While a tape backup won't help restore anything done on your computer since the last tape was made, regular backups will assure you of retaining all but the most recent changes.

They will also save you from the hassle of reinstalling complex and cantankerous software, should your hard disk ever be murdered by a power outage or die of natural causes.

Mike Himowitz can be reached by E-mail as 71655.1327

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.