#1 & #2, Yes , most coaches that's the set up.
, The converter/charger uses the coach batteries as a buffer to minimise voltage spikes and is wired into the system on the battery side of the disconnect relay. Also if you're on shore power there is no need to use the battery disconnect, it's function is to prevent battery drain while the coach is in storage.
EDIT: If you go to the " Quick Links " drop box , under your welcome message and click " Edit Signature " you can type in your coach info and it will automatically appear below your posts as mine does below this one. Saves typing it in every time you post.
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.