To all the experts or struggling enthusiasts like myself - I really hope someone can enlighten me as to why my system is suddenly behaving this way:
My setup:
- 2x5kva MultiPlus II Inverters - 48v grid tied system
- 4.5kW PV via a SolarEdge HD Wave 5kW PV Inverter - AC Output coupled
- 6kW PV via a Victron 250/100 MPPT charge controller
Recently (which could relate it to a firmware update), my PV Inverter is getting throttled when my Critical Loads exceed a certain value (about 4kW). My battery is not full (83% in this case) and my PV Charger (MPPT) does not bring enough power to sustain my loads and charge my battery. This leads to my battery actually discharging while the sun is at max:
What is interesting is that when my critical loads decrease, to say 2kW, the PV Inverter kicks in again. This also happens when I add an AC Load (on the AC input side). Discussing this with a friend lead us to consider maybe the Factor 1.0 rule applies, but surely this should not apply as my PV on the AC Coupled side is only 4.5kW. But something makes me think that it has to do with either:
- Prioritizing the DC coupled over the AC coupled (which does not make sense to me), or
- It's trying to protect the system from an potential overload if the loads suddenly disappear
What is also interesting is that when the grid is off (this happens due to our lovely nationwide loadshedding) the PV inverter produces as expected and does not get throttled:
I'm running ESS assistant and feed-In is switched off (I'm not feeding back into the grid). There seems to be no frequency shifting happening in these cases (based on my VRM analysis, so I'm assuming the Multiplus or GX is communicating with my SolarEdge PV Inverter via modbus.
Can anyone please help me explain this phenomenon?
Previously @Izak (Victron Energy Staff) from Victron has been super helpful in diagnosing a comms issue between SolarEdge and the GX device, so I have all the faith in this community :)