I don't bother with the "chassis ground" with my deck mount converters.
My Vector inverter user's manual says its chassis ground is to reduce radio and tv interference, but I don't know if that is what it is for on a converter.
Might as well add this photo of when I used the chassis ground as an anchor for a strain relief where I was having trouble with heavy cables with silky strands staying in the set screw terminals. That was on a 100 amp PowerMax. Never know--somebody might find that method useful.
The don't mix grounds thing also came from the inverter world where you must not bring the chassis ground around to the neg input. Instead the chassis ground goes to the frame independently.
