Check to see if the battery terminals might be shorted to the metal chassis of the RV.
Yes your converter/charger is bad.
You might be able to use a small battery charger to run your lights instead of a more expensive converter, but probably will need to have a battery anyway to prevent the converter or charger from going bad again. You can get away with a small battery, because you will not be camping without electricity.
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
If there's a WILL, I want to be in it!
I havn't been everywhere, but it's on my list.
Kangen.com Alkaline waterEscapees.com