UPS Maintenance

An Uninterruptible Power Supply (UPS) provides power to your computer system when the mains power supply fails.

Is essence it is a box containing one or more batteries that store power when the mains supply is working. When mains power fails the batteries provide power to an inverter that in turn produces 240Volts to feed the protected equipment (usually a computer and monitor)

Most UPS's are designed to provide power for long enough to safely shut down the attached computer system.

Depending on the rating of the UPS (in VA) and the power requirements of your computer system (in Watts) you would expect the UPS to maintain power for between 15 and 30 minutes.

To get the most from the batteries in your UPS you should regularly completely flatten the batteries and allow them to fully recharge. This will help to extend the overall life of the batteries and increase the length of time the batteries can provide mains power to protected equipment.

To flatten the batteries we need to remove power coming INTO the UPS and continue to draw power FROM the UPS. This forces the batteries to provide the power to the connected equipment until they are flat.

When the batteries can't produce power any longer the computer system will turn off suddenly, as if some one pulled out the power cable. We don't want this to happen when Windows is running, so we need to stop Windows from loading as it normally would.

A simple procedure to help keep your batteries healthy follows:

• Shut down all equipments connected to the UPS.
• If your computer can boot from a floppy diskette place a NON-BOOTABLE diskette in the drive (we don't want the computer running Windows).
• Turn on the connected equipment.
• The computer should report a 'boot' error but remain turned on.
• Unplug the cable going INTO the UPS from the power point.
• The UPS typically will beep every few seconds to alert you to a power failure. (Some have a button to turn off the alarm)
• Wait until the computer turns off. The batteries have now been discharged.
• Reconnect the mains power to the UPS.
• Wait for an hour or so to give the batteries in the UPS a chance before starting up your computer system as you would normally.

Never plug any devices into a UPS that draw HEAVILY on power such as laser printers.

Don't overload the UPS by plugging in too many computers. A 600VA or lower rated UPS will supply 1 computer and monitor. An 850VA UPS will supply 2 computers and monitors. Remember LCD monitors use less power than CRT monitors and will produce a lower load on the UPS.