Solar Panel Chassis Grounding

[MikeD]

I'm in the process of adding solar panels to my 2720 (battery on the tongue), and have a grounding question. From what I read (including the info in the installation guides for my panels and charge controller), it appears that I need to run a new wire (bare copper, 8 to 10 guage) from the chassis to the charge controller and the frame of the solar panels. My understanding is that this is an electical saftey issue of the charge controller (even though the negative is bonded to the chassis at seveal points), and also one for the panels (possibility of lighting strike, ...).

Is this what others have done ? This would mean that I need to run a three wire cable to the panels rather than the 2-wire cable I had planned upon. No problem - safety is paramount, but I wonder what other's have done.

Thanks, MikeD

p.s. I guess that my confusion is that there is no real Earth ground (only a floating chassis gound) on a trailer unless you are plugged into shore power. Earth grounding in a trailer confuses me.