A computer UPS (uninterruptible power supply) battery backup is designed to keep a computer running normally in the event of power fluctuation or loss. Its batteries can keep a system running anywhere between 5 and 90 minutes, depending on the model. The backup may beep if the computer is being run from the batteries or if there is a problem with the UPS. There are several steps to take to diagnose the reason for the beeping and find the proper solution.
Verify that the computer is plugged in and is receiving power. In the event of power loss, a UPS will continue to beep until power is restored or the silence button is pressed.
Press the test button on the panel to verify that the computer can run for several minutes on battery power. The beeping may be a warning that the batteries are becoming old and can no longer hold a charge.
Disconnect any equipment that draw large amounts of power from nearby outlets. Large devices such as refrigerators and heaters may temporarily drop the line voltage, causing the system to be switched to battery power for a few seconds.
Check the outlet's line voltage using a voltmeter. If the outlet isn't providing enough voltage, some models may allow you to reduce the minimum acceptable line voltage. Check your model's documentation on how to change this setting.
Connect only required accessories to the UPS such as the CPU and monitor. Other devices, such as speakers, lamps and televisions should be connected directly to the wall outlet. This will reduce the strain on your UPS and provide longer battery life.