When purchasing a surge suppressor:

￿Make sure the surge suppressor meets the appropriate product safety certification for your location, such as Underwriters Laboratories (UL).

￿Check the maximum amount of voltage the suppressor allows to pass through the line. The lower the voltage that the suppressor allows to pass through, the better the protection for your system.

￿Check the energy absorption, or dissipation, rating. The higher the energy absorption rating, the better the protection for your system.

￿Check for line-conditioner capabilities. A line conditioner smooths out some of the normal line noise (small voltage fluctuations) of an electrical supply.

Line conditioners

A line conditioner protects your system from the small daily fluctuations in voltage from an electrical supply. Most systems can handle this variation, or line noise, without problems. However, some electrical sources include more line noise than normal. Line noise can also be a problem if your system is located near, or shares a circuit with, a device that causes electromagnetic interference, such as a television or a motor.

Some surge suppressors and uninterruptible power supplies include simple line-conditioning capabilities.

Uninterruptible power supplies

You may lose data during a total power failure. A standby Uninterruptible Power Supply (UPS) uses a battery to keep your system running during a power failure. The UPS enables you to shut down your system normally, but not run the system for an extended time.

If you purchase a standby UPS, make sure the UPS includes surge suppression and line-conditioning features.

72Managing Your System