[PNW Fireguy]

Lot’s to digest here however your PV output based upon the time of year and your stated parameters is not way off mean numbers. If your roof is curved and you have both parallel strings on the same SCC this could effect the MPPT for the SCC assuming that you are using an MPPT vs PWM SCC. Separating the strings to individual SCC’s will help maximize each strings output. Based again on what info you provided it sounds like you may be using 190watt panels that have an IMP around 9 amps. If that is the case the amperage output from your array is inline. The factory solar wiring at your PV array voltage would be a challenge for me. You can check the voltage output of your array on the roof and then check the voltage at the SCC input to get a idea of your voltage drop. The voltage not the current should be your concern for that wire run. Think of it as the pressure available to push the 14-15A of current from the PV array to the SCC. I have factory installed 10AWG wiring from my roof to the basement but my PV array runs at 150vdc. Any voltage drop is neglible. One more item if your panels have bypass diodes then shading degradation is minimized. Most modern panels have them but you can easily verify by opening the connection box on the back of panel or via the manufacturer spec sheet.

Added some historical data for reference.