I decided that I would upgrade to dual batteries and install a Blue Seas Systems Add-a-Battery. This will allow me to use both batteries if needed for starting while isolating the batteries when running.
This also has the added advantage of charging my "starting" battery first and when it is fully charged it switches over and charges the "house" battery.
I don't have anything connected to the house battery so right now so the second battery is just an extra starting battery, but I'm sure an iPod docking station isn't too far fetched. The installation was quite simple and this setup should give us a little extra power when we need it.
Note: the black cables you see in the photo above are all positive (+) cables. (The auto parts store didn't have pre-made red cables to I bought black and wrapped the ends with red electrical tape.) The small black wire coming off the ACR is a ground (-) wire and goes back to the batteries with the three positive cables but it is hiding it in the photo.
The illustration on the left is the recommended setup. The illustration on the right is my slightly modified setup.
- Instead of connecting the ACR at the battery posts, I connected it on the live terminals of the on/off switch. So the "hot" lines coming out the top of my switch are actually connected to the same post on the on/off switch as the batteries.
- My picture only shows three cables coming out of the bottom of the switch. I do not have the "house" power line (seen in the diagram on the right in gray). This would be added later if I add a house circuit.