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"Uninterruptible power supply (UPS) protects computer and files"

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Dear Jim: I need an uninterruptible power supply (UPS) for my computer. A power outage wiped out my brothers' entire hard drive. What size UPS and what features do I need? Will a big one use more electricity? - Jen G.

A: Most people consider a battery backup UPS to be a convenient luxury so they can still use the computer when the electric power goes off. They don't realize if the power goes off while the computer is accessing the hard drive, the heads can hit disks and destroy all your files.

UPS systems also have powerful surge suppression built into the electrical outlets. They should protect your computer from all surges except perhaps a direct lightning strike. At the first sound of thunder, even at a distance, shut down your computer and unplug it, the telephone and/or cable modem.

A larger UPS will not use more electricity than a smaller one. All of them in the home and home/office size consume only several dollars worth of electricity per year. This is the electricity needed to operate the electronic circuitry, indicator lights and battery charging.

Selecting the proper size of UPS is important so it can handle the electrical requirements of your computer, monitor and any other peripheral equipment. The capacity of a UPS is rated in VA (volt-amps). If your system requires more electricity than the battery and inverter in the UPS are rated for, it will overload the unit and it will not perform properly.

You can just buy a large one to be safe, but it may cost $300 or more as compared to a properly sized starting at only $50. Look at the nameplates on your computer, monitor, etc. for the amps listed. Multiply this by 120 volts to get VA. The sum is the VA your system needs. You might increase this amount by 20 percent for any future computer components you may purchase.

Most of the UPS manufacturers' web sites also have online VA calculators. You just select the type of computer processor, number of drives, monitor size, and other peripherals and it recommends the proper size UPS.

Automatic voltage regulation (AVR) is a good feature to have. This is often available on all but the least expensive UPS's. AVR automatically adjusts the voltage to your computer in case of low (brownouts) or high voltage conditions. When the voltage gets too low or high, the battery takes over.

Consider the number of electrical outlets you need on the UPS to handle the components. Some models include software which automatically closes files and programs and then shuts down the computer if the power goes off while you are away. Look for a model with an equipment replacement warranty if a surge damages your computer system. Some will cover $50,000 damage or more.

Instant Download Update Bulletin No. 742 - buyer's guide of eight UPS manufacturers (34 models), VA ratings (350-1500), styles (floor or tower), dimensions, number of backup powered outlets and surge protected outlets, AVR, equipment damage warranties, automatic shutdown software, features, prices, and sizing chart for 10 typical PC systems.

Dear Jim: I was recently told that I should not let the cold water run when I brush my teeth because it wastes water and energy. I understand about the water, but how does it waste energy? It is cold water. - Sandi H.

A: Running the cold water has little impact upon your own energy bills, but it does consume a lot of energy overall before the water gets to your house and after it leaves your house.

Electricity is needed to pump water to the water tower and to run sewage pumps underground. The water you use is treated at the water plant using more energy. The treatment chemicals have to be manufactured and delivered to the plant which also consumes energy.

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