question

If your batteries are old, and have had a lot of deep discharge, they are probably nearing the end of their service life.

With your system, there is no way the BMV can influence the charge from the MPPT's - this would require a gx device.

The information you present suggests that the internal resistance of the batteries is relatively high, so when being charged, the terminal voltage at the MPPT's and BMV is rising faster than normal, tripping the MPPT's into absorption and float earlier than expected. It will also cause the BMV to synchronise it's SOC to 100%.

If equalising the batteries, and making sure all the connections are clean and tight does not improve the situation, the only solution is new batteries. I assume that your system is 24V nominal - you don't provide details.

Thank you Mike , yes its 24 volts but a neighbours system so unfortunatly i dont have the oppertunity to monitor it as i would my own . Conections are tight and clean and im going to pop over Thursday and manualy Eqalize them as you sugest and see if it helps . Hydrometer showed between 1.22 and 1.24 at eht time they are suposed to be 100% , some of the cells were clear fluid and others brown or half and half in the Hydrometer but have been assured they have never dropped below min fluid level and theres quite a large amount of fluid between min and max levels .

As a tempoary measure to get some charge into the bateries i changed from Adaptive Absorption to Fixed Time, do you think 4 hours is safe ?