Batteries are in a 2005 37' Newmar Kountry Star Class "A" motorhome. I would have thought they were completely charged from the night before as I drove 150 miles ran the generator for a couple hours in the afternoon and shut everything down except for the furnace that I set at 60 degrees for the night. The refer is set to auto so I assume it was running on LP. Not sure of any other electrical drain over the course of the evening. The current reading on the onboard volts is 12.9 to 13.1 the generator has been running since 7:30 this morning. I would think the batteries are completely charged by now.