Have a Cyrix-CT (battery combiner) between my service batteries bank and my starter battery (which is connected to the boat motor / alternator), so the use service bank is never able to discharge the starter battery, when the motor is running, as soon as the starter battery is charged the battery combiner opens and starts charging the service batteries.
I have purchased a Phoenix Smart IP43 12/50 (3) Charger with 3 outputs, to use when the boat is on shore (so no motor running). Can I connect one output of the charger to the service batteries and another to the starter battery to allow the proper charging of each battery (isolated) or I should just connect the battery charger to the services batteries and the charge of the starter battery should be made through the battery combiner only.
Thanks for the reply, connecting to only the service battery that two main issues,
Changing the services before the starter (is always nice to have the starter ready )
Lose the monitoring functionalities for the isolated perspective (stop knowing the effective state of each battery)
Forces to rely the service batteries circuit for keeping up the starter (i.e, if you need to make changes on the services connections you will need always to verify that the starter is still connected (which could be avoidable if you have them separated).
Create a single point of failure (the battery combiner)
If you want to do it right you delete te Cyrix and install an ArgoFet.
With Cyrix, no battery charges first than the other, they charger at the same time as I said before. Start battery should be full when you plug into shore power no need to have that charged first.
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