Hello,
I have an on-grid system with the following components:
- 3x MultiPlus 5000
- 3x batteries, for a total of around 45 kWh
- 1x Fronius Symo 10 kW (3-phase)
- 1x MPPT 250/70
- 1x MPPT 150/100
- 1x EVCS
- Venus OS running on a Raspberry Pi 4
For some reason, once the combined output of the three MultiPlus units reaches a certain threshold, the system starts pulling energy from the grid. This only happens when the load is spread across all three phases. If only one MultiPlus is under load, it will use the full battery power without any issue.
I can see it trying to draw more power from the batteries and then throttling down once it reaches around 120 A total battery discharge. DVCC is off, so it shouldn’t be throttling due to battery limitations. Each battery is capable of delivering up to 100 A, so we’re not even close to their combined limits. There are also no error messages from the system.
The system is configured correctly for a 3-phase setup. However, I suspect this behavior might be due to a hardware mismatch between the MultiPlus units. I originally started with a single-phase system, then added a second MultiPlus (in series), and later a third to create a full 3-phase system. I assumed hardware differences wouldn’t be a problem in a 3-phase configuration — but now I’m not so sure.
Even if it is down to the hardware issues , which multiplus should I replace ? There should be a way to check this out .
Any idea where I should look to troubleshoot this?
Update : Fixed it , i had to update the system to the latest firmware both on the multiplus side and venus OS, I though the system was quite up to date since the last update was beginning of the year …
Sorry for the spam.
Thanks in advance!