We are currently sailing our 2002 356 in the Great Lakes for the summer. To help battery life while on the hook-I installed (2) 100 watt panels. My battery bank consists of (2) separate 12v batteries wired in parrellel. And I can select 1,2 or both with the battery selector switch. So I connected the combined output from the solar panel to controller and then connected the controller output to battery 1. That seems to be working fine, but since the solar panels are putting out 20v in good sun I would like to charge both batteries. My problem or question is how can I do this. Since the negatives of the 2 12v batteries are already connected it would be simple to simply jump a lead from the solar panel conductor positive lead at battery 1 to battery 2. Thus charging both batteries. However unless I’m missing something-doing this would then make my battery selector switch useless because the battery positives would the be always be connected. I need advice. Thanks