trying to get it to work properly with an existing SMA X25 photovoltaic inverter. Both the Victron and SMA systems are designed for self-consumption only.
Initially, we found that the Victron system wasn’t recognizing when the SMA had excess energy and wasn’t charging the battery. Later, with some troubleshooting, we discovered that the beta version of the Cerbo GX firmware v3.50-34 works well for charging the battery, BUT:
EVERY EVENING BETWEEN 18:30 AND 18:50, THE SMA RECEIVES AN INSTRUCTION FROM THE CERBO TO CHANGE THE PARAMETER “Operating mode active power setting” from the position - “External active power setpoint” to the position OFF.
In addition to the main problem mentioned above, there is also a communication delay. I suspect that there is a delay in sending the signal, probably slower than 1s (SMA expects the instruction every second).
What changed per recent v3.50 betas is the the GX can now, as a new feature - default disabled - control the SMA. Zero feedin just like has been possible with Fronius PV inverters for a long time.
Same for Solar edge: v3.50 adds power limiting as an option.
But updating the GX shouldn’t break an existing system - we’ll look into this; thank you for the report @ToGan
Using the official firmware, the system is only in monitoring mode.
When using the beta software, the system functions identically to a Fronius system. It limits charging… everything operates as expected until 18:40 when the GX device sends a signal to the SMA inverter to disable external control. Consequently, the inverter fails to resume normal operation the following day. The SMA is conected in AC In.
Hi again @ToGan , I looked further into this, and I think I have a solution.
For exactly your use case, where our new feature to have the GX do power limiting causes issues because of an already installed meter, we have added an option to disable this new feature.
Thank you!
Today, I saw that the new version on firmwear and was uploaded and I installed it immediately. The feature was disabled by default, and now when I checked the SMA, everything is okay with the external control setting!
Good day,
I waited a few days to observe the system’s behavior before providing feedback. However, for three consecutive days, the function has been automatically disabling itself. The current version is 40, and the function is in a disabled state.
