ESS Setup:
Multiplus II 24/3000/70, Cerbo GX, MPPT 100/50, SmartShunt, LifePO4 210Ah 24V batteries
The issue is that Multiplus gets an error
Error 8: Ground relay test failed on VE.Bus System (Multiplus)
This is only when Neutral of OUT2 is connected to common Neutral busbar
If all sources of OUT2 are on separate neutral bus this error does not occur
According manual I haven't found any requirement to separate neutral on OUT2