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Chapter 5 Maintaining the Cisco Global Site Selector 4490
Using Power Protection Devices
–Adding machines
–Laser printers
–Facsimile machines
–Any other motorized equipment
Besides these appliances, the greatest threats to a system’s supply of power are surges or blackouts caused by electrical storms. Whenever possible, turn off the system and any peripherals and unplug them from their power sources
during thunderstorms.
If a blackout
Using Power Protection Devices
A number of devices are available that protect against power problems such as power surges, transients, and power failures. The following subsections describe some of these devices.
Surge Protectors
Surge protectors are available in a variety of types and usually provide a level of protection commensurate with the cost of the device. Surge protectors prevent voltage spikes, such as those caused during an electrical storm, from entering a system through the electrical outlet. Surge protectors, however, do not offer protection against brownouts, which occur when the voltage drops more than 20 percent below the normal AC line voltage level.
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| Cisco Global Site Selector 4490 Hardware Installation Guide |
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