Murraycroexp
Veteran Expediter
Where I got my mattress pad draw info.
http://www.electricblanketinstitute.com/features-benefits/actual-cost-to-run.html
http://www.electricblanketinstitute.com/features-benefits/actual-cost-to-run.html
Blanket does not draw much. We used one last year. No problem. Next time we pass you need to look at our setup.
If it draws 60 Watts, that's 5 amps off a 12 volt battery. (amps x volts = Watts, or, Watts / volts = amps)
You definitely don't want that kind of a draw off a cranking battery.
It would seem all you really need is a 100AH marine/truck battery for your aux battery, hooked to the alternator via a battery isolator. Then use a battery charger hooked to the generator to keep the aux battery charged up while sitting for extended periods. I would still recommend a battery monitor.