As we all know, MultiRS consumes some power when connected to the grid. More or less, this is a couple of kWt every day. When you have a 3-phase system, it multiplies.
There is a feature in RS called “conditional AC input”, where you can put the inverter in island mode if it falls in some criteria, so it will be disconnected from the grid as soon as the criteria are met.
I found a possibly incorrect behaviour of this feature when there is a 3-phase system. So here are some steps to reproduce.
Given: 3-phase MultiRS system (one tracker version) with Cerbo, meter and solar.
Steps to reproduce:
- Activate feature on phase A. Set “Load Condition” → “Connect when load is higher” to 4800W with 0 seconds delay, Disconnect to 3000W with 5 mins delay.
- After activation on phase A, you see the whole system goes to the island mode (as inverter A drops the grid)
- Repeat the same settings on phases B and C
- Run load, higher 5000W on inverter B (or C).
Actual result: Inverter overload alert, and the whole system goes offline.
Expected result: Inverter B should trigger grid connection to ensure it can provide the required power (in the way it works in a one-phase system). It looks like invertors B and C have no idea that the grid actually there and behave like there is no grid at all. If same scenario will be triggered on inverter A everything works correct. If you start configuring from inverter B and than runs high load on B everything works fine. So only inverter where first configuration happened knows what to do