Maximum Inverter Power with Grid

When I have assigned ‘Maximum Inverter Power’ to 750W, and power on 2kW heater, for the first around 10 seconds the energy was fully taken from energy storage. Then it slowly got down to the 750W while the rest was taken from the Grid.

This was for Multiplus-II 5000 for 1PH + Cerbo GX, then I have tested it for Multiplus-II 8000, 3PH + Cerbo GX and the result was similar (for Multiplus-II 8000 everything was slower).

Inverter is configured with ESS.

  1. What explains this observed pattern?
  2. Are there configuration options available to implement strict discharge limits (at least for on-grid operation)?

ESS has a ramp time, so it will always behave like that.
It has been well discussed before.