For the past 3 days I have now witnessed this. My AGM’s 200Ah are allowed to discharge during the night to 70%.
At around 10H00 the next morning when all PV is out of the shade the MPPT (150 | 35) ramps up and charges up to 18amps (the most I’ve seen) but gradually throttles back as the batteries are nearing the full mark which I completely understand must happen due to internal resistance, absorption stage etc.
But, it is not reaching 100% SOC. It gets to about 95% and then the day is over and sunlight gone.
I don’t understand how this happens as my daily loads are no more than 600W, and I have a 2,4Kw array. 96V VOC and charging capability of 31.5A
I get the idea that the MPPT throttles back to quickly. Can this be heat problem? I have no external temp sensor connected to the batteries
Maybe a setting that needs to be adjusted somewhere?