When my 3kW Quattro is in inverter mode and grid at the same time is connected it happens that the Quattro shuts down and gives a message for overload. As soon the Quattro is set to charge only it works normally.
Every time the Quattro is set to inverter mode it tries to feed current to grid, just as a spike, and the “drossel sound” is heared as a shot. This happens approximately once an hour, and are seen as negative spikes in the VRM advanced picture. The setting for operation is: "Country/grid code standard: None: (feeding energy from DC to grid not allowed)"
