An APC power supply helps to protect your sensitive electronic equipment from power surges and failures. Depending on the current condition of the battery, the unit may emit sounds to alert you about normal operating conditions or issues with the unit. Paying attention to these beeps can help you to diagnose and correct any issues with your device.
According to Schneider Electric, an APC battery system may emit an infrequent single tone to let you know when a system functions normally. Provided the tone only emits a single beep and doesn't display any insistent behavior, such as long tones, double beeps, or a beep that recurs on a regular basis, you shouldn't need to take any action on the device. Check for damaged or loose connections to rule out issues with the cables. Try plugging in a tested and working lamp to the wall outlet to see if the lamp flickers. If it does flicker, contact an electrician to rule out wiring issues in your home.
Your system may emit a series of beeps at a set interval. Four beeps every 30 seconds may indicate the unit has switched to battery power and no longer receives power from the wall outlet. The most likely scenario involves the battery getting unplugged from the wall or an outage interrupting the supply of power. Brief power interruptions may result in only one or two beeps. The APC unit may determine that the input voltage received doesn't provide enough power for your computer, resulting in a disconnect from the power supply. If the issue occurs repeatedly, try a different power outlet and consult an electrician.
Attaching too many high-powered devices to your APC backup could result in a continuous tone. The continuous tone lets you know when the device detects an overload condition; the tone usually accompanies a red indicator light. If you have any equipment that doesn't need protection, remove it from the battery backup supply and plug it into a regular wall outlet with a surge protector. Make sure you only connect devices using the provided outlets and avoid the temptation to add additional extension cords or plug outlets to the device.
Continuous beeping accompanied by an amber colored light indicates a nearly exhausted power supply. The power supply protects itself from a complete discharge that could harm the components by shutting down before the battery is completely drained. When this occurs, shut down all of your equipment until you can restore power to the device. The warning beeping indicates that you only have about two minutes to shut down your computer to prevent data loss. Connecting your power supply to your computer with a USB cable and installing software for your APC device allows you to change the warning to five, seven or 10 minutes. You can also set your computer to shut down automatically when the warning goes off.
The worst-case scenario involves a continuous beep for one minute that repeats every five hours. This indicates the battery failed the self-test. You can manually check the battery by pressing and holding the power button until you hear the second beep. If the unit continues the behavior, you need to take it in for repair. You can order a replacement battery for out-of-warranty units. Request a replacement from APC through the Warranty Services tab on the APC Support website (link in Resources).