ground

Re: ground

For proper operation of your solar panel/charger system--it does not matter if the panel is grounded or not.

For fire safety--You can decide (but code would require proper grounding to frame ground with mounting hardware or a "green wire")... For example, if the panel glass broke or the positive wire shorted to the frame--the frame can become energized.

Once the frame is energized--it is possible (probably not likely) that ~10 amps from a short circuit would go through a poor frame to aluminum skin connection (or if they used aluminum backed insulation in the RV) to over heat and set the wood frame on fire.

So--if you are like 99% of the world out there--most people would not ground the frame.

If you are very concerned about fire and electrical safety--then the frame should be properly grounded. And if you properly ground the frame--make sure to use proper components/materials (typically stainless steel hardware with "star washers" to cut into the aluminum and tin plated copper for the electrical connections). Using standard galvanized/steel hardware will cause local corrosion and you will not have a good electrical connection over time).

--Your choice.

-Bill