Just google "RV solar" for lots of handy links on that subject.
I have yet to see a clear and through coverage of the complex systems in the class A vehicles. I am a retired ASE Certified Master Auto Technician, and it took me about 3 months of studying various sources, reading wiring diagrams, and poking around on my own MH to figure out how all the various electrical systems interact. I ended up with a folder of about 25 pages of notes and diagrams to use as my personal guidebook.
This is a great place to start your studies:
(Note that his example system is a simple one as often used on travel trailers. Class A coaches are quite a bit more complex)
2008 Itasca Meridian 37H & 2015 Flagstaff T12RBST
2011 & 2012 Len & Pat's "One lap of America"
27K miles & 41 states in 13 months - Woo Woo
Yellowstone Lake 6-1-2012