Uninterruptible Power Supply

An Uninterruptible Power Supply (UPS) device can be placed between the electrical receptacle and the computer (or other electronic equipment) to isolate it from an outage. When the UPS senses a change in voltage or a power outage, it switches to battery backup. The batteries provide time to save information and shut down. Some models use software that can close and save your files before safely shutting off the computer. This is typically referred to as an unattended shutdown.

UPS types

There are three types of UPS:

  • Off-line UPS allows power to flow until it detects a change in voltage or a power outage. Then it switches the computer from the incoming line to internal batteries.
  • Line-interactive UPS features an internal circuit that interacts with the incoming voltage to increase or decrease the incoming voltage. It does this without resorting to battery power. Regulating the voltage without resorting to battery power helps the batteries last longer and assures they are only used during a power outage.
  • On-line UPS powers the computer or other equipment from an internal power supply 100% of the time. AC power from the incoming line is converted to DC, converted back to AC and then fed to the computer. This provides the highest level of protection.

What does MGE recommend?

MGE recommends a UPS be applied to electronic equipment that could be adversely affected by power problems. These include PCs, PLCs, phone systems, etc. Choose the type of UPS by how critical the equipment is that needs to be protected.