How does solax EVC "Green Mode" work?

In GREEN Mode, the EV-Charger will maximize the use of surplus power generated from the inverter. According to the minimum start-up charging power, the charging current can be divided into two levels as 3 A and 6 A. The default level is 3 A. In the 6 A level, the EV-Charger won’t use the power generated from grid at all. In the 3 A level, the EV-Charger would start charging only when photovoltaic power supply is more than 3 A. Meanwhile, if the photovoltaic power supply is less than 6 A, the EV-Charger needs to buy extra electricity from grid for minimum start-up charging power(1.4 kW for single-phase, 4.2 kW for threephase).