Hmm, so thinking about this a bit more: do the Peak Shaving current limit settings in the screen above only apply if there is a grid meter?
Said differently, if there are only loads on the ‘AC output’ side of the system — so no grid meter needed — then the AC Input Current Limits become the limiting factor for Peak Shaving.
I had a similar situation, there seems to be a bug.
My setup;
MP2 with AC and DC PV, all loads and PV on AC output, no external grid meter (using the internal one)
What worked for me;
Switch grid metering to external (even though there is no external grid meter).
Enable peak shaving and set limit (i only enabled import limit).
Switch grid metering back to internal, the peak shaving settings remain unchanged.
I have not yet checked to see if peak shaving actually works.