for one thing, there should be paperwork from the converter manufacturer, in your owner's manual stuff. that would give you some info.
second, you didn't mention what year it is. i think your model is relatively new, so it should have a 3-stage one.
third, all RVs have parasitic power drains and if you don't have it hooked to shore power or have solar panels, your battery will be dead in a few days.
as sherdep said, hook it up to shore power, get the battery recharged and install a battery disconnect switch.
with a disconnect switch, once they're recharged, you just turn the switch and they'll stay charged for weeks. no need to keep it plugged in.
Dan-Retired California Firefighter/EMT
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing a 2014 Ford F150 SCREW XTR 4x4 3.5 Ecoboost w/Max Tow Package
4pt Equal-i-zer WDH and 1828lbs of payload capacity