That’s the issue, nothing happens, I can increase it to 40A but the feed to grid remains limited to 5000W per phase or about 21A, even when my AC PV inverter is doing 95% of the “work”, the Multi RS only feeds back the remaining amount until the 5000W is reached.
For example: my SolarEdge PV inverter is producing 4000W per phase, the Multi RS only “adds” 1000W to that to make it 5000W, however when the PV inverter is not producing anything, the Multi RS is feeding back at full power; until 5000W is reached.
Note that this issue only applies to feeding back into the grid, not when consuming from grid.
It seems the grid current setting only applies to feed from grid, not feed to grid.