I have 5 KVA Multiplus 1 connected to 340 AH 48 V battery bank. It is connected as a UPS so 99% of the time it is in float mode. The battery voltage according to the Battery Monitor varies randomly about 0.1 V p-p at times and at other times its very stable. When a change from noisy / stable occurs its associated with a temperature change sensed by the battery monitor. See trace attached. It seems battery temperature as shown on VRM traces has a 1 degC temp resolution yet I believe internally it is 0.5 degC as I have seem 16.5 degC on the remote console display. I suspect that when temperature has a xx.5 deg value then the charger is noisy. In graph below voltage is noisy between about 22:00 to 02:17. Temperature dropped from 20 to 19 deg at 02:17