Is 4 gauge wire big enough?

I'm adding a 3rd battery to the boat I will have, 1 battery for starting, and 2 for the stereo bank that will be run parallel. I have some 4 gauge power and ground wire left over from my stereo install so I'm wondering if it is big enough for connecting the 2 stereo batteries together.

I don't see why not, if its a short run. I think the ACR installation recommends using at least 4awg, and that is connecting 2 batteries.

That should be fine. The issue is current times distance. You have a lot of current but not much distance.

David

Good to hear. Now I need to figure out what to do with my prosport 12 dual bank battery charger. I'm thinkin about using it two ways but am unsure which will be best or if there are other options. All three batterys are group 24 marine deep cycle batteries.

1) Have bank 1 of the charger goin to stereo battery 1, bank 2 off the charger goin to stereo battery 2, and the starting battery left to be charged by the alternator.

2) Have bank 1 of the charger attached to either of the stereo batteries and bank 2 of the charger attached to the starting battery.

i was told to hook the charger up to the 2 stereo batteries as one, and the starting battery as the other.

don't know if that's right or not, but my buddy that has trolling setups on his bassboat did it that way.

Go route #2 because the starting battery can be partially discharged as a result of being in parallel with a depleted stereo bank when on the water and lead acid batteries can self-discharge several percent per month. The charger will deliver more to the bank in demand so a majority of the 12 amp total capacity is still available to the stereo bank.

David