I carry a 25' 50A extension cord that is in a plastic tote box and it's rarely used. Actually it's used at my house and a few times we've reversed parked in a site because of the view.
I chose the PI HW50C power protector which provides protection that a autoformer doesn't but does not boost the voltage. Perhaps you want both. Low voltage is common on 30A pedestals and not so common on 50A pedestals.
"fire control" ??? Common in a boat bilge but where would you put it on a RV? Engine area, refer area, HW area, furnace area or? Smoke and propane detectors are common on a RV.
