That would be the Alpha I installed about four years ago because we kept getting interruptions while printing. It probably wants another set of 12v 7Ah batteries. I'll dig around and see if I got some slightly used ones.
There is a UPS in the hack room that is screaming for a new battery. I have turned it off and unplugged it from the wall. The screaming continues. I can poke a button to silence it for a few seconds but that isn't the attention that it wants.
The UPS was connected to the Prusa printer on the rolling white stand.