Hello reader,
First the setup: 3-phase domestic system with 2 Multiplus II 5000 70/48 per phase, Victron solar charger connected to DC (about 5kwp) as well as a DIY battery system. Additionally, ACout has AC-coupled PV installed (about 12kwp) as well as domestic loads.
Situation: whenever I switch “Ignore AC Input” on the Multi to on and put the system effectively into island mode, the Multis start raising the AC frequency to 53Hz in roughly 30sec intervals:
This effectively shuts down the AC coupled PV, as I suppose is the intention of the system. But: why? The battery is not full nor at voltages close to those configured for cutoff. I have the BMS even issue a “charge request” as if empty yet the Multis keep shutting out the AC PV supply (when grid connected, this immediately has the Multis pushing every electron they can get hold of towards the batteries). I can see no configured reason why the system would think it should regulate the AC PV down?
The DC coupled Vicron Charger does not get regulated, it keeps providing current.
So: what am I missing?
I am at loss, so is my dealer. I am hoping someone in this forum has an idea or maybe even faced the same problem?
Cheers, Christian