Hi All.
For RV'ers who run "Multiable Battries", its really pretty simple, to keep track of the "Negitive Battries"" and the "Positive Battries". Doesn't matter is your working with "6 Volt Battries" or "12 Volt Battries".
I have always painted or used Red Tape to mark all of the "Positive Cables". And "Black Paint" or "Black Tape", on all of the "Negitive Cables". And I
use "White Paint" or "White Tape" on "Ground Cables". Been doing it this way for over 46+ years now, and have never wired anything wrong. Also a few "Pictures" are really worth their weight I gold.
Roy has some good example of how the different types of Battries are to be wired. Not picking on you, as we all had to learn one way or the other. For us old timers, like me, when I started there were no computers to go check stuff on.
It just takes a little bit of time and you to will be an old pro at it all.
Good Luck. Happy Travels. Dan & Jill & our two Small "YORKIE KIDS", who love to travel as much as we do.
1998-34 ft Rexhall, Rexair SL. 460 EFI. F-53. 7.3 MPG. TST TPMS. HWH Levelers. 5.5G Gen. Convection/Microwave Water Purifier/Water Softner. 2 A/C's. Alarm Systems. Honda EU2000i's W/Kit. Steer-Safe. CR-V W/SMI System. FMCA #F414397 Nam-Vet, 66-67-68&70-71