After 4 years, the Eaton 5P UPS trigger a battery alert that reminds you to replace the batteries. What’s common for any bigger solution to replace the batteries early, might not be the normal use-case for you. In Addition does just replacing the batteries not reset the battery alert of the UPS. You also do not find any option to reset using the menu. At least in older firmwares.


There is an easy fix. Just disconnect the main power and the batteries for at least 5 minutes. Make sure you hit the power on button after disconnecting all power sources. If you do not try to switch the UPS on without any power, the capacitors might just keep enough power to keep the flag set.

After five minutes, connect the batteries and then the mains. The UPS should now be reset and asking for the system language.

Another thing I learned is, that I do regularly make sure my NUT service is stopped and then disconnect the main power to check the batteries. I’ll replace them when they do no longer keep up providing power.