Stand Alone Charger

Is your WFCO a constant charger or a 3 stage charger? What is the max amp output of the WFCO in your trailer? How many AHs in your boat marine batteries? If you have 2 12v batteries in your TT with 150 AHs total, a 3 stage portable that charges at 30 amps is fine. Do you charge your marine batteries from shore power or an on board genset? If shore power only 30 amp output is fine it will just take longer to recharge than a higher amp output if batteries are depleted. To charge your batteries from a genset It would take too long and use too much fuel to fully charge them so the most practical way to charge from a genset when dry camping is to charge from 50%SOC to 80%SOC then fully charge when you come home using shore power. The last 20% takes a long time, kind of like the half life of uranium.