Here is a link on the bcc
http://www.precisioncircuitsinc.com/...R-BCC-RevC.pdf
Converter can charge the house batteries directly and charge coach batteries thru bcc, coach alternator can charge house bats driving thru bcc. Bats coach and house can be linked thru bcc for emergency start switch e.g. Start coach with dead coach bat or start genny with dead house bat.
Bcc also has protections aganst putting slides out while coach running.