Have 2 - 100 amp sok batteries installed in our RV. Since we do not do a lot of Boone docking the main function of the batteries is to provide power to the 12v system and to power via a 3000w Aims inverter for the fridge and minor appliances. The Aims is an inverter/converter and because of the a/c wiring the inverter stays one whenever the RV is in use. The system is wired with a shunt and monitor. I realized today the batteries stop charging at 12.7%.
If I intentionally drain the batteries to cut off an reconnect to the charger they charge normally until they hit 12.7% and then stop. Any suggestions? Does this mean one or both batteries have a defective bms?
What is the battery voltage when you see 12.7% charged?
I assume you are configured for 12 volts and the batteries are wired parallel. If you are using a Victron BMS (Battery Monitor System), make sure the capacity is set to 200 amp hours.
You may be getting fully charged but the BMS thinks the capacity is much larger therefore telling you the batteries are only getting to 12.7% charged.
Normally this is the setting issue. If BMS has issue, it would completely stop take a charge or discharge.