Without knowing what type of power converter you have, it's hard to say exactly what to check. But in my 3 years at a RV dealer as a parts guy, I learned there were often fuses on the power converter itself. These are not located where all the fuses are for all the lights, vent fans, power stab jacks, power awning etc. Often they were polarity protection fuses in case you plug into a bad outlet or the battery gets hooked up 'bass ackwards'. Typically you need a screw driver to take covers off in order to see them.
FAA A&P mechanic, ex-RV dealer parts dept
Retired B-52 Gunner/Flight Examiner, B-52 Crew Chief
2016 Jayco Eagle HT 29.5 FBDS w/ 15,000 BTU AC, 50 amp service, upgraded counter top, thermal pane windows, elec. stab jacks, outside grill, backup camera and MORryde pin box.
2011 GMC 2500HD DURAMAX/ ALLISON