Review on 🌞 Newpowa 10A MPPT Solar Charge Controller for 12V Battery with LCD Display, Dual USB Ports, Negative Ground - Ideal for Gel AGM and Liquid Batteries, Off Grid Solar Panel Charger - Up to 130W by Cris Drew

I have a 210w panel. I was monitoring load data with a Raspberry Pi. Sometimes it reads over 18 volts from the panel, but in direct sunlight for some reason the voltage is 15.5 volts. What I assume is floating charge charging? When the sun isn't shining directly, it reads 18 volts from the panel. When I go out in the sun early in the morning, I notice that the charge controller goes into fast charge mode at 10 o'clock. Hence the high jump in my charts at this time. But I have an obstacle obscuring the panel about an hour before noon. After this time, the charge controller doesn't seem to go into boost charging mode anymore, instead it floats, which keeps the charge at a fairly low voltage. Sometimes I get 11 amps, but even in direct sunlight it sometimes only draws 2 amps per battery. It is strange. The temperature sensor has been changed several times.