With Dutchman/Keystone who knows...
On most units I have worked on there are couple of things that "Solar Prep" could mean. On my current Coachmen Concord it means there is a port on the side that I can plug portable solar panels into. On a friends Lance TT it means there is wiring run behind the fridge from the roof into the converter cabinet for roof top solar panel install.
From the sounds of it you have the port version. Got a picture of the fitting above the outlet? The industry seems to be primarily using the
Furrion fitting or the
Zamp version of it. I have the
Renogy 100 watt suitcase kit and had to buy a
Zamp adapter to go from the Furrion outlet to the SAE connector on my solar panels.
Aaron
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