I have two arrays on the roof of my fifth wheel camper. One utilizes 4 x 100 watt 12V panels in parallel. Shading prohibits series installation. I'm using a PWM controller and typically only see 60% harvesting. Since roof space is limited and adding more panels not feasible, the most effective way to harvest more power would be to upgrade to an MPPT charge controller.
The Victron Configuration Wizard recommends the SmartSolar 100/30.
However, after watching a Victron video, I learned that the controller generally doesn't start producing power until array voltage is 5v higher than the battery voltage. Thereafter, only a 1v difference is required to continue operating.
The optimum panel voltage is ~ 17.9v with open circuit voltage around 21.5V.
With a future LFP battery conversion planned, will the switch to an MPPT controller be worthwhile? Given a float voltage of 13.5-14V, I'm not sure there's enough "headroom" in the panels to allow the controller to start.
Am I understanding this correctly?
I suppose that if I knew the correct panel voltage throughout the day then I would be in a better position to decide. But the PWM controller, by nature, drops the voltage to just above battery voltage. I never get a sense of what potential the panels could offer.
