Calibrating Solar Assistant emulated BMS ?

[RedwoodJay]

My equipment is an EG4 3000EHV-48 inverter with two Lifepower4 batteries and Solar Assistant. SA’s tech support recommended having the battery's RS-485 connect to the inverter and use SA’s emulated BMS which is what I’m doing but it seems like the emulated BMS’s accuracy is not great.

To setup the emulated BMS, SA asks for the 80% SOC and 30% SOC voltages. Where do I find those numbers? I couldn’t find find the answer exactly but there is a graph in the Lifepower4 manual of SOC vs. cell voltage so I took those numbers and multiplied them by 16 (16 cells in the battery) for the following :
80% SOC voltage = 52.8V
30% SOC voltage = 44.8V

I attached a screenshot of the cell SOC graph to this thread with my calculated numbers in blue down the left side.

Do these number seem right? What values do other people use? Are there any tips on getting the emulated BMS running accurately?

BTW- my system has been running for almost 2 weeks now and seems to be working great but I just have a few questions like this one. So far so good.

Thanks, I appreciate the help.

 

[AZ Solar Junkie]

Why not use the closed loop communication with the batteries? That’s what I did when I was using the 3000ehv and I monitored it with solar assistant. No emulated BMS needed…

 

[RedwoodJay]

The RS-485 goes between the batteries and inverter for the closed loop comms. It is not possible (as far as I know) to insert SA into the loop since both the inverter and SA would want to be the host. Am I not understanding something?

 

[Crowz]

I use a victron smart shunt to handle battery info on mine.

Very accurate so far.