its in interesting concept none the less.
I have seen battery balancer on aliexpress for about $35
thats cheap but i think it's discharge is around 0.5A which is very little for a 600A bank!
Id like a little more control over this, would be good instead of wasting the energy by loading, the idea can be reversed and add charge to the lowest bank.
I have just came up with a way negative voltages wont happen..
it means the arduino can be powered by the banks ob batteries too.
Dc-Dc converters always usually have common grounds which works well for the diagram I uploaded now
I'd need to divide the 0-1023 by 30V
bank 1 would read 24v and bank 2 would read 12v.
Quality batteries should give a good 5-7 Years
My batteries are not sitting on the floor. they are raised a little too to prevent the bottoms of batteries holding a thermal difference, Ive read a lot on batteries.. and things such as a full DOD even once can F them for good... not good at all,
So the idea to build a arduino project that others will able to follow, can build an alarm into it even.. some sort of detection..
buying two volt meters is also another way to seeing.. but automated always seems better!