Last weekend I swapped out my three multiplus II 5000VA units for three Multi RS Solar 6000VA units. Currently I have two 48V 300Ah batteries connected that can charge 75A each and discharge 100A each. The BMS (JK-BMS) is connected to BMS-CAN on the Cerbo and communicates maximum charge/discharge and charge voltage to the Cerbo / VRM. I can see these parameters in the remote console as well.
After installing everything ESS was working immediately but I had to install a Beta Venus OS version to get DESS to work as well. So I understand that this is all still beta-testing! Thanks for adding the Multi RS to the list of possible DESS machines!
I do have one important issue: The Multi-RS-System seems to completely ignore the maximum discharge setting set by the BMS. It also ignores setting a maximum discharge value through Victron-connect, even though it is grid connected (this was also noted by Harold Halewijn in his video: https://www.youtube.com/watch?v=MTBLz_9uDrM&t=800s). This resulted in my BMSes disconnecting the batteries due to an over discharge situation. At the moment I have fixed this issue by setting the maximum current on AC Input 1 to 13 Amps AC, this way maximum discharge is kept to approx 190Amps DC.
On top of the BMS communicating max charge/discharge values I used Nodered in the past to adjust the maximum charge value based on battery temperature by adjusting “Venus system → DVCC system max charge current (A DC)”. This also seems to be broken for the Multi-RS system. The last set value was 150A for both batteries together. The strange thing is, that the Multi-RS system seems to be respecting this value, since I have kept the default 100A as maximum charge value through Victron Connect… Still charging is kept to a maximum combined output of 150A DC.
I wanted to describe what is happing to aid further improvements, if there are any questions I’ll be more than happy to answer them.
My Site ID is: 402251
I do have three questions:
- How is the maximum charge / discharge current that I can set through Victron connect in the Multi-RS interpreted? Are all values from the three units added together for the total max charge/discharge to/from the battery? This is what I would expect.
- Is it planned to also respect the set max discharge current in the future?
- Will controlling the maximum charge/discharge through Node-Red be possible in the future?