I just updated my MulitPlus 2 from 498 to 502 on a 24V system that had fully charged Pylontech Lithium Ion batteries.
My 24V system has been configured for the MultiPlus charger to be OFF and direct control of my system voltage using BMV 712 Battery Monitor. All units have the latest firmware.
When I connected directly to my Mk3 interface the expected firmware upgrade was initiated and went smoothly. Then when I updated the Mulitplus to 502 it reset to factory defaults which was advised to happen. As I stated first my batteries were 100% charged when the factory defaults were activated the battery charger was turned ON, the system voltage went quickly to 28.9V which was the factory default, which caused all the Pylontech BMS to Alarm, which isolates each battery from the system.
It would seem the factory defaults for the MulitPlus II 24V system could be set for a non-disruptive condition and would strongly suggest the defaults should be set for Lithium Ion batteries to 28.2V to avoid a major system disruption. (Which required manual intervention to reset each battery.) Or the charger could be set to OFF.
Please advise if future steps could be taken to avoid system stresses and manual resets of the battery BMS when installing MulitPlus II firmware updates.
