Shore power--93 230 DA

[ks65609]

They're probably starting batteries, no big deal.
The good thing is that you already have a dual-batt setup on a single engine boat, so it's a simple matter to swap out the extra starting batt for a deep-cycle or two and use that for your "house" battery (the house battery is what powers everything on the boat- the starting battery is isolated/connected ONLY to the engine). This assures that even if you run the house battery down, you always have a fully-charged battery for starting.

Installing an inverter is a relatively simple DIY project that will make your time aboard a lot more enjoyable (inverter+ blender= margaritas ).

Okay, thanks again. I think I am good to go for my next project in the spring. Just need to understand how my dual battery switch set up works including charging from the alternator if I change out or add a deep cycle house battery.

Ken

 

[ks65609]

They're probably starting batteries, no big deal.
The good thing is that you already have a dual-batt setup on a single engine boat, so it's a simple matter to swap out the extra starting batt for a deep-cycle or two and use that for your "house" battery (the house battery is what powers everything on the boat- the starting battery is isolated/connected ONLY to the engine). This assures that even if you run the house battery down, you always have a fully-charged battery for starting.

Installing an inverter is a relatively simple DIY project that will make your time aboard a lot more enjoyable (inverter+ blender= margaritas ).

I wish I had started this discussion after I had made sure I really understood how my dual battery bank is wired. From the pics I have, there are three positive cables routed to the switch (settings are off,1,2,and all) and no negative. I would think this is not a parallel battery wiring set up based on other dual battery wiring diagrams I have been able to find. Also, am I correct in saying the switching mechanism provides the isolator function as well. Based on this wiring, either battery could be used as the house battery. I was told the norm is to use number 2 . If I replace number 2 with a deep cycle unit, I am now confused as to how the switch is to be set for starting and cruising. Once anchored would I switch to no. 2. I know that cranking and deep cycle batteries cannot be charged simultaneously.

 

[tobnpr]

Your boat could be set up any number of ways.

You're correct that they're not paralleled. The battery ground is connected directly to the engine block (with a short jumper between the grounds on the two batts).
Typically, both the house and starting loads will come from the same battery in a factory setup, that being determined whether the switch is set to "one" or "two" (never to "all" unless you need to parallel them for an emergency start).

The best way is to disconnect the house loads from the battery switch (if it's wired that way) and connect them to the house battery as I mentioned above- that isolates your starting battery. For this to work, you would need to have a "battery combiner" installed off your alternator so that both batteries will be charged when the engine is running.

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

As far as the battery switch providing isolation to protect the alternator if switching while running- most newer switches do, but to be safe check your particular model.

 

[ks65609]

Your boat could be set up any number of ways.

You're correct that they're not paralleled. The battery ground is connected directly to the engine block (with a short jumper between the grounds on the two batts).
Typically, both the house and starting loads will come from the same battery in a factory setup, that being determined whether the switch is set to "one" or "two" (never to "all" unless you need to parallel them for an emergency start).

The best way is to disconnect the house loads from the battery switch (if it's wired that way) and connect them to the house battery as I mentioned above- that isolates your starting battery. For this to work, you would need to have a "battery combiner" installed off your alternator so that both batteries will be charged when the engine is running.

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

As far as the battery switch providing isolation to protect the alternator if switching while running- most newer switches do, but to be safe check your particular model.

Thanks for the explanation. Therefore, with the current set up, a setting of 1 or 2 will charge and/or consume the respective batteries individually and I would need to be cautious not to run down one unit continuously.
The solution you have recommended eliminates this as long as I install the battery combiner. I quite like this idea.

Thanks
Ken