See about 700 watts with meter off solar array (57V @ 12 amps) at input to controller. When hooked up Controller is reading 300 Watts approx (47 V @7 amps). Actually went through the entire system today thinking the issue must be panels or cabling but checked right at input to controller and panels and cabling are good. System worked when initially installed but has degraded. Assumed panel degradation but just seemed like to much so tore into it.
How did you measure this? Voltmeter and DC clamp meter simultaneous?
What about the MPPT output voltage, if you have a poor high resistance joint or breaker on the MPPT to battery wiring the MPPT output voltage would rise to the set voltage before the battery was full limiting the input. Capture a screenshot on Victron Connect of the status screen when the panels are throttled back to 300W and you settings screen.
Comercial Electric Multi-meter.
This meter only does up to 10 amps dc
Discconect all your solar panels from the array and check each panel Voc and Isc against the name plate spesifications during good sunshine at midday.
If all panels are within specs start checking mc4 connectors and all connections in the solar combiner. The problem does not lie with the Victron Mppt according to your screenshots it is spot on just not enough pv input wattage.