I am by no means an expert, just based on my experience with my last three coaches, they all had the same set up, there will be a 4-5 second delay after the Genny stabilizes and the relay kicks over!
The power from the shore power and the Genny run through the Furrion box, then a single line runs from there to the main power panel under my bed. From there AC power is distibuted!
That Furrion relay may be a place to start!!
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