Realize this is a REALLY old thread, but wanted to post what I ran into that ended up being my problem. On my 2021 33RLS there is a "bus bar" in the lower right hand corner. The main battery line from BOTH the house battery and from the converter connect to this bar on the lower left post. This bus bar is actually a bus bar connection to various sized breakers. The post that my battery and converter connected to is a 50A ignition protected auto reset breaker. I managed to smoke mine! It looks like the attached image. I am replacing it with a circuit breaker, and stepping up to an 80A unit as I have some additional 12v (fridge) draws that are also attached to this bus bar and I believe why it actually fried.
***ADVISE DISCONNECTING BATTERY AND SHORE POWER BEFORE THIS!!!***
To access the breaker, you must unscrew the bar from the backer wall mine was simply two wood screws. Once the bar is loose, the fuse is removed by removing the two 3/16" nuts and pushing the fuse through the back. This is the primary fused link for the rest of the copper bar that runs across the top. It appears that each of the additional links may have various 50/30/etc. sized auto reset breakers. Replace as necessary, hook it all back up and be on your way!
Attached images show the bus bar, the plastic cover hiding it and the actual breaker that burned on mine.