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One of the best investments a PC owner can make to extend the life of their computer and reduce the problems they have is an uninterruptible power supply or UPS. The UPS goes between the wall electrical outlet and the computer. Don't confuse it with a standard surge protector, as it is so much more. The UPS is comprised of three basic parts the battery charger, the battery and the power inverter. The electrical energy from your houses' electrical system runs the battery charger that keeps the internal battery charged: in-turn the battery runs the power inverter, producing a constant 120 volts to run the computer. The typical 117-volt nominal power supplied by you electrical utility will vary in true voltage supplied between 88 and 138 volts. These are extremes but your day-to-day voltage excursions are substantial. There are two things that a computer does not like Power Surges And Heat. The UPS will prevent the first one and my next topic will address the second. Being that the UPS relies only on the electrical energy from your electrical outlet to keep the internal battery charged, and that the battery supplies a constant voltage to the power inverter, your computer Never Sees A Variation In Power Input. Therefore, no variation, no surges, no low or high voltage = longer, trouble free life for your PC. Turning on and off your PC is also a form of surge-So Leave It On All The Time and set your monitor to go off or turn on the screen saver. A little power consumed, but much longer life for your PC. Also, consider the power required to manufacture the new parts necessary to replace those destroyed by surges (trade-off?).

Additionally, UPSs have another great feature, Automatic Power Backup, the battery in the UPS is isolated from the house electrical power so if the power goes out your computer will still be powered and running. The battery charge and therefore the power to run the PC is only good for a finite period of time (this depends upon the size of UPS being used) for most applications I recommend a 500VA size unit. A 500VA UPS will run a tower type PC with a 17" CRT monitor for about 8-9 minutes. This is plenty of time for you to shut down your PC properly.

However, what if you're not home or not available when the power goes out? Not to worry, most UPSs have an Automatic Pc Shutdown Feature. A cable (USB or serial) is connected between the UPS and the PC and working with some supplied software will automatically save your work and shut your PC down properly before the UPS battery is depleted. When the power is restored you start your computer and everything will be as you left it.

A typical UPS has two sets of outlets; one set that is battery backup protected and the other that is surge protected only. In most cases, plug only your PC and your monitor into the battery backup outlets and all other devices into the surge-protected outlets. Never plug-in a laser printer or some other high current device into the battery backup outlets. There is normally no reason to plug in a printer of any kind into the battery backup outlets. However, if you must, then buy an Appropriate Sized Ups that can handle the extra load.

Surge Protectors:

A standard surge protector, although a good investment but it only reduces the peak voltage spikes of a power surge. These spikes can be power company induced, or if your PC is on the same electrical circuit with a large inductive load like the motor in a refrigerator or an air conditioner. The surge protector will not prevent high and low voltage transitions of your electrical power.

If you use a dial-up telephone modem connection you MUST have a surge protector on your telephone line prior to entering your computer. There are More Power Surges on a telephone line than on your electrical power line. I have replaced many computers due to the lack of a telephone surge protectors. Most of the failures are due to static electricity or lighting on the telephone line. The high voltage surge enters the computer through the unprotected telephone line and into the modem. Since the internal modem is connected to the motherboards data bus, the surge travels throughout the computer in a blink of an eye destroying everything. Today most good quality surge protectors, and all UPSs have built-in telephone surge protectors. If the surge suppressor you're using does not have one, get a dedicated telephone surge protector (Radio Shack) or buy a new UPS or surge protector with one built-in. If you have a fax machine-the same holds true for it, cheap insurance.