I have an off-grid solar setup with two completely separate systems. One has four 200 AH batteries, one has three 200 AH batteries. Each have their own MPPT, inverter, and BMV 702 battery monitor (all Victron gear).
The only item I use on both battery banks is a Centaur 12/80 charger. Currently, I only use one output from the charger and charge each bank separately, connecting the negative lead to the load side of the shunt, and the positive lead directly to a battery in that bank.
Although there are three outputs on the charger, they share a common negative.
My question: How do I charge both banks simultaneously while still measuring the current going into each system? Do I split the negative with a busbar?
My current plan is to install two four-way battery switches (similar to this: https://www.bluesea.com/products/6007/m-Series_Mini_Selector_Battery_Switch_-_Red), one on the positive and one on the negative cables coming from the charger, then have them going to a battery and load side of the shunt on each bank. This would make switching between banks easier and safer than using clips.
Second question: If I did this, could I turn the switches to "both" and charge both banks simultaneously, while still measuring the current going into each bank? Are there significant downsides to this, as far as temperature monitoring?
Cheers.
