My three battery banks. Your thoughts?

Sorry , Im a admin on the 3 power sites & I get into the terms or abbreviation's that most AME use.
2/0 and 4/0 ("ott" = "aught")

Pauls post of # 19 is incorrect on size & Strand .
4 & 2 is correct Not the 0 . & this is a AC feed from a grid supply .
2 = 200 amp , 4 = was a 100 amp supply feeding the breaker box . in AME

Sloth

 

Smaller the number the greater the diameter. 28 is infinitely smaller than 12 look at your power cords not the jacket but the wire it's self and read the wire size on the cords .
I only used what i had already in my building .
I probably could have used 0/4 but I had a surplus of 0/2.

 

American wire gauge - Wikipedia

A chart