30more, I am attaching a generic schematic for the DC connections which “may” be similar to your coach. If it is similar to your coach then for the converter to burn up, I suspect that your use/store was on (latching relay was closed). So then it is likely your coach batteries were either discharged or dead or not connected perhaps, which is normally where the bulk of the current would come from to operate the jack pump motor or to start your generator. Hope this helps you visualize a bit.
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