I have a 48v Mecer 5kva inverter that has been connected up to solar panels. Up until recently I have not had the possibility of grid power.....but just now got it! So now I want to connect the house to grid power and use my solar system as a backup. My question.....can I connect the main grid utility directly to the inverter? I believe the answer is "yes." So, then my next question has to do with switching between grid power and solar. Is there an automatic transfer switch within the inverter that will take care of this? Final question.....if I connect up the grid power to the inverter, will it charge up my batteries to keep them topped up....thinking specifically for cloudy days and at night. Thanks!