For the third time in 2 months my B300 on a AC300 setup read in the forties S.O.C. then dropped to one percent with a very small load. I’m confident, or at least was, that the charge was there in that I monitor my wattage in and wattage out closely. I almost exclusively charge with P.V. except when this happens and I fire up the generator for a grid charge. Any thoughts-------------------