Today when I got home my 170ah Renogy battery was on 39%. I left the bus under the trees so the solar panels didn't have any chance to charge the battery. I plugged the bus to the grid to charge the battery with the multiplus compact. After maybe 90 minutes I went to check on the battery and I noticed that it was on 78% but the CCGX was showing PASSTHROUGH. Why the multiplus stopped charging the battery before finishing charging and went into passthrough mode?