Back-UPS 650 long, loud beeps several times a day

[IxalanPower]

Why is my 650 emitting long (7-8 seconds), loud beeps intermittently? Some days it does this 2-3 times, some days zero, but usually at least once a day. The unit seems fine, solid green "Power On" light, and the "Replace Battery" light is not illuminated. There are only two devices plugged into the unit (TV and A/V receiver), and they do not power off when the loud beeps happen. The unit is about 8 years old and has a non-OEM battery in it.

[Teken]

Connect the UPS to a computer running the APC PCPE / PCSS software. What active faults / errors are displayed or recorded in the logs?!?

Once both systems are connected perform a static and dynamic tests of the system.

Static Test: Remove all connected loads. Unplug the system from AC Mains. Time how long the unit operates for and what both the LCD / PCPE indicate as the operational runtime vs actual runtime before it shuts down.

Dynamic Test: Once the battery cartridge has been fully charged as confirmed by the LCD / PCPE software. Connect the same loads you had before while on.

Disconnect the USB cable from the computer. Remove AC Mains from the wall outlet. Time how long the system operates like this and compare it to the LCD.

You’ll see one of several behaviours in either tests. The system will immediately or within a minute shut down. If that is the case for the static tests this indicates the battery is EOL.

If you see the same behaviour in the dynamic test this simply affirms the same. ☝️

If both tests run for more than 10-30 minutes (depends on load) compare that to the APC Runtime Calculator. If the runtime is not similar this affirms the battery needs to be replaced (EOL).

If the operational runtime is close enough than the problem could be elsewhere. 

What is the battery installation date / in APC PCPE software vs the production date of the 3rd party cartridge?!?