AlexSR

They are connected by CAN.

Only if it came from the inverter. They have been connected to the same inverter for 7 months without any issues.

Dear all, Could someone give me some directions on what could have happened with my battery array? My system is composed of a 3000W PV array, a Growatt SPH4000 inverter and a 3x Pylontech US2000C battery array. The system was running without any issues for the last 7 months, yesterday mid-morning the batteries were being charged and at 42%SOC (inverter indication) all of them came up with the red alarm LED steady on and a "battery open" message on the inverter display. From the batteries manual, it seems that this means that they are in protection mode, from the inverter manual the "battery open" says to check the battery terminals. I disconnected everything and let it rest for 30 minutes to see if something would reset, didn't work. Additional troubleshooting done: Cables and terminals were inspected, but nothing was found. Disconnecting the battery cables to the inverter, if I turn the batteries on they go to run mode and operate (apparently) normally. I have measured the voltage in each battery module and for each one, I got a 49,5V reading. If I reconnect the battery cables to the inverter and turn the batteries on without powering up the inverter the batteries jump immediately to protection mode, if I connect only one battery module at the time to the inverter the same thing happens. When I turn the inverter on a start cycle is done on the batteries but they jump back to alarm mode. The inverter itself is working fine without the batteries. I have bought a 48V 5A 53.6V charger and tried to charge each battery individually, I has able to do so but I end up with different voltages in each battery (51.6V,50.2V,51.2V) but all show the SOC LEDs in full charge. The batteries themselves seem to also be working fine if they are not connected to the inverter. I am guessing here but I think the BMS on the batteries uncalibrated it self and maybe is generating some issue (if this is possible at all). Any ideas or troubleshooting tips will be appreciated Thanks! Attachments WhatsApp Image 2022-04-12 at 16.17.48.jpeg 175.3 KB · Views: 4 WhatsApp Image 2022-04-12 at 16.12.25.jpeg 260.2 KB · Views: 4