The Batter Control Center is the black square box with fuses and wiring connections in side it. Below the board are a couple of solenoids. I am not sure but your coach may not charge the chassis battery off of the converter or inverter. This would require a charging system designed to do that function. You could add a batter tender or similar free standing charger to keep the chassis battery charged.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7