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Preface
15
KEEX-1850 Series User’s Manual
Uninterruptible Power Supply
Uninterruptible power supply (UPS) systems offer the most complete protection
against variations on power because they use battery power to keep the server
running when AC power is lost. The battery is charged by the AC power while it
is available, so when AC power is lost, the battery can provide power to the
system for a limited amount of time, depending on the UPS system.
UPS systems range in price from a few hundred dollars to several thousand
dollars, with the more expensive unit s allowing you to run larger systems for a
longer period of time when AC power is lost. UPS systems that provide only 5
minutes of battery power let you conduct an orderly shutdown of the system,
but are not intended to provide continued operation. Surge protectors should be
used with all UPS systems, and the UPS system should be Underwriters
Laboratories (UL) safety approved.