1. The FUSE. Is this the 250/300 amp fuse? Or the fuse on the Xantrex unit?
2. There is NO converter. You have a 100 amp CHARGER on the Freedom.
3. You MUST have a Battery connected when you have an Inverter/Charger. This type system will not function correctly without a battery connected.
4. You state you connected the batteries correctly. After 37 years as a tech, I could buy a new car if I got $10 for every customer that would swear on a stack of bibles he connected the new batteries correctly. You need to doublecheck the battery connections.
5. On your year Newmar, there is a Bi directional relay charge system that even with the Chassis batteries disconnected can supply power to the Positive side of the Chassis thru the Inverter/Charger.
6. WHY are the chassis batteries disconnected??????? Doug