SailingOn - The wife uses her's as a heated LAP Blanket while watching HDTV when we are OFF-THE Power grid alot. Great for taking the chill off... Its a 50WATT size and draws around 5-6 AMPS if you crank it up. Leaves it on low setting and it cycles a lot... The one on the bed is dual warmer that lays on top of the mattress.. I don't like them so my side is always off. Here again I think it draws 6-7AMPS from my INVERTER but cycles off-on alot with low setting. I think this is a dual 80WATT model. It is amazing what just a small amount of heat on top of the mattress does when you have quilts and sheets on top of you.. Never had any issues with them. The one around the easy chair takes a pretty good beating. I also have a 12VDC low wattage lap model that I keep in the truck.
We plan out our DC CURRENT usage when camping off the power grid with our 255AHs Battery bank and watch the main Dc VOLTAGE meter. We don't want it to drop below around 12.0VDC by 8AM each morning so we can run the 2KW Generator during breakfast to bring us backup to a good 90% charge state in a short three hour time when allowed to run our generator.
Roy Ken