We have the same issue with multiple Smart BMS CL: They are not letting significant charge to the Lithium batteries even though the alternator is running at high speeds.
Screenshot attached - we have a 100A alternator, engine running at 2000rpm, the device shows 5% load and no significant current flows towards the battery. We had the same / similar issues on multiple boats and caravans.
Any idea what the reason could be? It can not really be linked to the batteries - we have tried bridging the M8 connectors with a BMS cable, still the same behavior..