3 way fridge

Hey kman I use to run mine straight of the 2nd batt with twin core 6mm no problems.

Mine runs off 2nd battery with 8 B & S

Batteries in van charge off car via 6 B& S Both through a pair of Anderson plugs.

Battery wire has 60 amp resettable fuses at BOTH ends

Fridge has 25amp fuses at both ends.

Pin 2 on van 7pin plug has 6mm charging the breaksafe unit only.

I run my camper trailer fridge from the battery in the c/t while travelling. This battery is being charged from my second battery in the Patrol while travelling via an Anderson plug. I believe this is the normal way.

kman,

Either should work, but option 2 is far better than option 1, though obviously more expensive.

Why? - The fridge draws at least 12 amps continuously when running on 12V. If connected directly to the van battery, both fridge and battery will draw current from the alternator while the engine is running. That 12+ amps being drawn by the fridge will result in reduced voltage reaching the battery so that it can never be fully charged.

In either case there must be a controller up front to disconnect the line/s from the vehicle battery when the engine isn't delivering charging current. If you do decide to go with option 2, it will also be necessary to disconnect the 2 lines independently, otherwise with the engine not running, current will flow from the van battery forward to the engine bay through the battery charging line, then back to the fridge through the fridge line. (I use 30A headlamp relays to switch these lines independently.)

Hope that makes sense.

John