My hybrid has never been without power. I keep it plugged in on a 20A circuit 365 days a year. I was told yesterday by a motorhome owner that it was not good to do it, although he did not give me any ...
How often do you check your batteries for fluid loss? That's about the only thing it can harm (other than using up the hours your converter/charger will last). Check batteries about once a month until you know how much water is being boiled away. COULD be quite a bit or could be next to nothing depending on your converter. Good luck / Skip