I have recently upgraded an existing solar system by adding a second MPPT Bluesolar 150/70 Tr. The original system was composed of 2 Multiplus-II and a single Bluesolar 150/70 Tr all connected to a Cerbo GX. The battery was composed of the 2 cells from Tesla.
Upon connecting the new MPPT we measured the voltages at the battery side and it was 57V but what I wasn't aware of at that time, was that these batteries could only be charged up to about 49V so I didn't find it strange to have that voltage. As the new MPPT was also connected to the Cerbo GX I wrongly assumed that the voltage from both MPPTs was being controlled by it and thus no further configuration was needed to the system.
Unfortunately the system was left like this for 2 days before we finally realizing the mistake. Upon disconnecting the battery and measuring its voltage it was at a safe level of 49V.
My question is if has this killed the batteries or do they have an internal BMS that effectively disconnects them from the 57V source causing no harm to the cells inside?
Please let me know your thoughts.