Installing a battery monitor

[Mystic38]

if you note what the "recommended" looks like, I would make a strong suggestion that you do use a busbar distribution for both -ve and +ve.. ie...do not use the battery terminal as a connection point. They are not expensive and the significant benefit is that you can remove an individual battery without taking down the entire house bank

[B.R.Sail]

Originally Posted by smac999

not having read all the posts.

you need to move the neg from the starter battery to go from the starter battery to somewhere on the load side of the shunt. you'll probably need a large bus bar there after the shut. as you'll have a few large wires. inverter neg, boat neg, starter battery neg, and you also seem to be missing the inverter chassis ground which will be a 1/0 or 2/0 going to this bar was well. do you have one?

the monitor would be setup for the amp hours of the house battery only

in the pic you are also missing a switch and class t fuse on the inverter pos line.

the 1-all-2 switch setup looks ok. you have emg. power available to power the dc panel from the engine batt if needed. and can also parrellel if needed. just leave it selected to house all the time.

though I'm asuuming the engine has it's own switch and cable though? or is it coming off the common lug of that same switch? because in that case you don't have a start and house battery... you really just have 2 equal banks. there is a difference.

If so I would look at the blea see add a battery kit. change that switch and add an acr.

Thanks very much to everyone for the advice. I will move the starter battery negative to the load side.

To answer a few of your questions- 1) I will add the bus bar on the load side of the shunt since there will now be a number of large wires connected there. 2) I do not see a large inverter chassis ground, but I will double check. There are only two 2/0 wires coming from the inverter. Pos and neg that were previously wired directly to the house batteries. The other wires look like A/C in and out and temperature sensor. 3) there is a large fuse on the inverter positive line but I failed to include that in my diagram. 4) I do not have a separate switch and wire for the engine. It looks to me like its coming off the common lug on the 1/all/2 switch. So as you described, both banks are probably wired the same. One bank just happens to be a starting battery, while the other bank has two deep cycle batteries that I use as the house.