Sorry to sound like a dumbass, I dont know much about dual battery setups.
If you run 2 batteries in parallel they will be both charged by the alternator, although if they are seperate is the 2nd generally (used for winches/lights etc) also connected to the alternator via a seperate connection or just charged when low??
Are there any benefits of a seperate 2 battery system, or does it simply to ensure that even after winch/light use you can still start on the main battery??
Cheers
Ollie
That ain't strictly true.
Wot normally happens is that a relay disconnects the auxilary battery until the alternator is charging. The alternator can then charge both batteries.
on the ones where the relay is triggered by the alternator lamp wiring - starting is carried out by the master battery, then when the lamp wiring drops to 0v, the relay is triggered and connects both batteries together, so that charging is carried out on both. As can be seen below....
only if the engine is running - which should been they are being charged.