Magnum inverters handle up to 17 volts DC. Outback also handles up to 17 volts DC. I suspect others are similar. The bigger question is do you have flooded batteries that need to be equalized or do you have AGM batteries that shouldn't be equalized.
You can turn off the auto equalization function, I think it's DIP switch #5. That's probably the simplest solution. One of the main reasons for an equalization charge is to "stir" the electrolyte to prevent stratification. That's hardly needed in an RV where the batteries are constantly bumping and bouncing down the highway.
