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Surge protectors with a very low overvoltage threshold cost upward of $50. They sacrifice themselves in the event of any significant overvoltage but are smart enough not to trip for just a small amount over the standard power levels. Additionally, most of these protectors contain electronic circuits that can «shave off» any overvoltage and ensure that the powered devices receive only the voltage they need.

Line conditioners are a much better choice for protecting against surges and spikes. Line conditioners use several electronic methods to “clean” all power coming into the line conditioner. The best models can be prohibitively expensive, but there is a way to get a kind of “natural” line conditioner. An uninterruptible power supply (UPS) uses a battery and power inverter to run the computer equipment that plugs into it. A battery charger continuously charges the battery. The battery charger is the only thing that runs off line voltage. The computer itself runs off steady voltage supplied by the UPS. When power problems occur, the battery charger stops operating, and the equipment continues to run off the battery. The power coming from the UPS is always a continuous 110 volts, 60 Hertz. Because the AC power from the wall never crosses over the battery charger to run the computer components, it’s considered a “natural” line conditioner. As you will see, the UPS is the solution for a number of power problems.

Power Underage Problems

Power underages occur when power levels drop below the standard, and they are almost as common as power overages. There are three types of power underages:

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