Surge Protectors.

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Surge Protectors.

• A power surge, or transient voltage, is an
  increase in voltage significantly above the
  designated level in a flow of electricity. In
  normal household and office wiring in the United
  States, the standard voltage is 120 volts. If the
  voltage rises above 120 volts, there is a
  problem, and a surge protector helps to prevent
  that problem from destroying your computer.

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Surge Protector
A simple MOV surge protector with line
conditioning and a fuse.
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• A standard surge protector passes the electrical
  current along from the outlet to a number of
  electrical and electronic devices plugged into
  the power strip. If the voltage from the outlet
  surges or spikes -- rises above the accepted
  level -- the surge protector diverts the extra
  electricity into the outlet's grounding wire.
• In the most common type of surge protector, a
  component called a metal oxide varistor, or MOV,
  diverts the extra voltage.
• As soon as the extra current is diverted into the
  MOV and to ground, the voltage in the hot line
  returns to a normal level, so the MOV's
  resistance shoots up again. In this way, the MOV
  only diverts the surge current, while allowing
  the standard current to continue powering
  whatever machines are connected to the surge
  protector. Metaphorically speaking, the MOV acts
  as a pressure-sensitive valve that only opens
  when there is too much pressure.

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Voltage Regulators

• A voltage regulator is an electrical regulator
  designed to automatically maintain a constant
  voltage level.
• Eg. Tripp Lite Line Conditioner LS606M Automatic
  Voltage Regulation with surge protection has 6
  outlets. Automatic voltage regulation system
  offers complete protection from brownouts,
  overvoltages and transient surges for computers,
  printers, fax machines and more.

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Uninterruptible Power Supply (UPS)

• An acronym for uninterruptible power
  source/supply. A UPS is primarily used as a back
  up power source for computers and computer
  networks to ensure on-going operation in the
  event of a power failure. Sophisticated units
  also have power conditioning and power monitoring
  features.
• Typically, a UPS keeps a computer running for
  several minutes after a power outage, enabling
  you to save data that is in RAM and shut down the
  computer gracefully. Many UPSs now offer a
  software component that enables you to automate
  backup and shut down procedures in case there's a
  power failure while you're away from the computer.

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• A UPS generally protects a computer against four
• different power problems
• Voltage surges and spikes - Times when the
  voltage on the line is greater than it should be
• Voltage sags - Times when the voltage on the line
  is less than it should be
• Total power failure - Times when a line goes down
  or a fuse blows somewhere on the grid or in the
  building
• Frequency differences - Times when the power is
  oscillating at something other than 60 Hertz

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• There are two common systems in use today
• standby UPS - runs the computer off of the normal
  utility power until it detects a problem. At that
  point, it very quickly (in five milliseconds or
  less) turns on a power inverter and runs the
  computer off of the UPS's battery. A power
  inverter simply turns the DC power delivered by
  the battery into 120-volt, 60-Hertz AC power.
  Standby UPS systems are far more common for home
  or small-business use because they tend to cost
  about half as much as a continuous system.
• continuous UPS - the computer is always running
  off of battery power and the battery is
  continuously being recharged. There is no
  switch-over time in a continuous UPS. This setup
  provides a very stable source of power.
  Continuous systems provide extremely clean,
  stable power, so they tend to be used in server
  rooms and mission critical applications.

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