I learned a few things at this stage too, surprise surprise. Converters and Inverters are different things (inverters change power down from 110V to 12v, converters convert power up from 12 to 110). Batteries are finicky.
We have a 155W solar panel, and a 12V, 4amp fridge, the kind for truckers and tailgate parties that run off a lighter socket. We’ve got a charge controller that I got with the panel, and then the converter that came with the camper, that also has a shore line. Two deep cycle batteries of dubious condition. Then a generator. And a 2amp battery maintainer. And a standalone converter unit, also for running off a vehicle lighter.
Figuring out how to put it all together involved a great deal of mental anguish, time on the internet learning about electricity (I was all good for Ohm’s Law, but when it came to the PEIR wheel I hit overwhelm), and looking for people who knew more than me that could explain stuff.
I think I hit an electrical turning point this time though. By the end of it, it just all seemed so simple. It just all follows back to what’s hot and what’s ground. For years, that has not seemed simple at all, but it’s not so bad.
So without all the many hours involved in the learning curve and emotions, here’s what I did. The solar panel is wired through its charge controller to the battery. The charge controller is awesome, because it reads out the panel output or the battery charge. The converter is suspect, so that is not wired to the batteries. It’s a glorified extension cord. It’s wired to the battery maintainer, though, so any time the camper is plugged into the genny or shore power, the batteries will be getting a little bit.