Looking for direction on sizing fuses, breakers and wire. This is the concept of my diagram so any corrections are welcome. This is for a 2014 RAM Promaster 2500.
I forgot to drop the inverted in. Thanks for the reminder.
You might consider designing in a Smart Shunt with a battery monitor or Cerbo GX.
Breakers/fuses should be the 1st in line and as close to the start and house battery + terminals as possible. I prefer fuses to breakers if you will also have isolating switches.
Consider a solar isolator switch near the input to the mppt otherwise your panels are constantly live to the mppt input and you can’t de-energise when working on the system
No need for an isolator switch at Orion input except if the vehicle will be stored for weeks at a time and you want to avoid the small parasitic drain.
A smartshunt or BMV 712 on the house battery negative will be useful for monitoring state of charge and also sharing exact battery voltage and current with the mppt and orion via smart networking for more efficient charge control.
Orion XS is a better choice for a 200Ah house battery. Smaller, cooler and more efficient too.
Consider adding a smart battery protect on house positive to automatically isolate loads when battery gets low.