If the inverter and battery are having communication issues, there are a number of alarms that could occur.
BAT_Comm-Fail, CAN_Comm-Fail, No-Battery, and Batt-ON-Fail are all alarms that may be displayed by the inverter.
The first thing to check is the brand and model of the inverter. Then check the Solis S6 HV Home Energy Storage Inverter Compatibility Sheet to make sure the inverter is able to support this inverter.
The next thing to check is the CAN (or RS485 if LG) connection between the battery and the inverter.
Download the Solis S6 HV Home Energy Storage Inverter Manual and go to page 55. Use the chart to determine if the correct wire colors are being used.
Look at the battery breaker, make sure it is in the on position. Check the high-voltage conductor connections as well, make sure no cables are loose.
Use the SolisCloud app Bluetooth connection to check the battery settings. Make sure the battery selected matches the brand and model installed. Go to Information, then check the Battery tab to see if the inverter is getting any information from the battery.
Use the flow chart attached and included below to troubleshoot. Please escalate to L2 if you are not able to fix the issue.
Keep in mind that once the issue with the battery communication has been fixed, it will take at least 5 minutes for the alarm to clear. However, the inverter should be able to get data from the battery immediately after the issue is resolved. Use the Information tab to view the battery details. If values are populated, then the inverter and battery are communicating. 