Hi, I have a standard 3-phase system with Multiplus II (3000 VA), cerbo gx, 2x MPPT and pylontech batteries (10.6kWh). I have the system grid-connected (AC-IN), in Czech republic. 7,2 kWp panels in two strings. Installed by a professional and reliable company, no complaint there.
I am testing DESS and noticed that often it’s importing a lot (>1kW) on one phase while exporting basically the same amount on another phase. In sum, it looks okay, but in Czech Republic, we get billed per phase… So I export (sell) on one phase for 1 CZK / kWh while buying on another phase for 6 CZK / kWh. So the sum is -5 CZK for me actually for that hour.
In Multiphase Regulation in Cerbo GX → ESS it is set to “Individual phase”, but it seems to me that DESS is still doing it by sum. Any insight why this is happening? Other than this I’m happy with DESS, but this behavior bothers me. I haven’t seen this happening with ESS only (DESS disabled).
I’m on spot pricing, where the difference between buying and selling is huge here in Czech republic – due to “regulated” price you pay for each imported kWh, on top of the price you pay for the electricity itself.
It’s not always the same phases. Sometimes L1 is buying while L2 selling, other time L3 selling and L2 buying etc.
Thanks for advice or hints. A picture to illustrate:
I’m experimenting with DESS just couple of days , but have exactly same experience. Standalone ESS with multiphase regulation set to individual phase works fine , but it seems that DESS ignores it. The issue is even more problematic when I use additional equipment (Wattrouter) to redirect surpluses to be used for heating up water, then I’m left only with massive consumption.
I’m new to Victron community, pleased do you thing that this forum is read by Victron Staff or is there some issue reporting tool ?
Thank you
Sadly absolutely the same problem, have built recently 4 systems that worked well without any problem. Now all of them showing this nonsense behaviour as described, exporting power on one phase and importing the same amount on another.
On one of the systems (3 phase home, single Multiplus on L1) same behaviour happens even if switched to external control with self written scripts for net zero…, a script that has worked for 5 years now without any issues whatsoever.
Same problem on another system with disabled DESS, during the night where it should discharge battery, it is exporting power on one phase, importing on another… that starts to get VERY annoying that there is no response from Victron for this obvously extremely serious problem affecting probably thousends of systems since even over the holidays lots of comments about this are popping up.
