What is a UPS?

An Uninterruptible Power Supply (UPS) is a device that sits between a power supply (e.g. a wall outlet) and a device (e.g. a computer) to prevent undesired features of the power source (outages, sags, surges, bad harmonics, etc.) from the supply from adversely affecting the performance of the device.

What are different topologies of UPS?

There are mainly three topologies of UPS i.e. Offline, Line-interactive & offline UPS.

What is Online UPS?

Online UPS involves the use of major part of the online power through an inverter. Inverter remains always "On" during normal operation of UPS. Due to which there will be zero transfer time from mains to battery and vice versa. This makes it true uninterrupted power supply.

What is Double Conversion?

This is type of online UPS in which mains AC power subject to first convert from AC to DC power with help of Rectifier and then DC to AC power with help of Inverter.

How can UPS help me?

A UPS has internal batteries to guarantee that continuous power is provided to the equipment even if the power source stops providing power. Of course the UPS can only provide power for a desired time (depending on battery backup time). Even if the outage is longer than the battery lifetime of the UPS, this provides the opportunity to execute an orderly shutdown of the equipment. Advantages:

  • Critical applications don't stop because the power fails
  • Users not inconvenienced by computer shutting down.
  • Equipment does not incur the stress of another (hard) power cycle.
  • Data isn't lost because a machine shut down without doing a "sync" or equivalent to flush cached or real time data.
  • What are the basic functions of UPS?

    A UPS traditionally can perform the following functions:

  • Absorb relatively small power surges.
  • Smooth out noisy power sources.
  • Continue to provide power to equipment during line sags.
  • Provide power for some time after a blackout has occurred.
  • In addition, some UPS or UPS/software combinations provide the following functions:

  • Automatic shutdown of equipment during long power outages.
  • Monitoring and logging of the status of the power supply.
  • Display the Voltage/Current draw of the equipment.
  • Restart equipment after a long power outage.
  • Display the voltage currently on the line.
  • Provide alarms on certain error conditions.
  • Provide short circuit protection.
  • How long UPS can keep supplying power after the mains power goes?

    It is mainly depends on for how much time battery system is designed for. It also depends on percentage of load.