[jcurtis934]

Well said cadman. The idle current on most inverters is very low, on the order of a few hundred milliamps. I just turn my on and off to minimize it's running hours and maximize it's lifespan. Personal choice as to what you wish to do. Transfer switches, whether built into or separate from the inverter just look for 120vac on the priority input which is usually the input connected to 120vac from your fuse/breaker panel. If no power on that input, the contactor flops over to the other input to get a source of 120vac. Good to see you educating yourself on the inverter install in your trailer!