I don't see the logic of wiring
the fridge direct to the controller and having dedicated batteries for just running the fridge.
We have 2 deep freezers and and a refrigerator
(plus other stuff) on our boat
. We usually provision for 5 months in the Bahamas
. I expanded our solar
array to 4 130W panels and a 50 amp BlueSky MPPT
controller. Our house bank consists of 3-4D AGM
batteries (about 630 amps). We can now run everything all day and night (assuming sunshine) without running the genset at all. That includes running the watermaker
everyother day off solar
. If I could make hot water
, the genset probably wouldn't run at all (except when the admiral wants her hair dryer).