Battery, Battery Switches and Possible Upgrade

[jwill323]

I'm thinking about replacing the batteries on the 323 this spring and since it's been freezing and snow covered here i've been thinking more about doing a larger upgrade. Current 12v system includes 3 batteries ( interstate group 24), 3 battery switches (4 way 1, 2, 1+2, off), 1 Blue Sea ACR, Generator (Kohler 5e), and a Charles 3 bank battery charger.

I have realized that i really have no idea how these are all wired together so i have reached out to Cobalt to see if I can get a drawing or schematic to see how all of this works together and what I think I could do to upgrade the system, I talked to customer service but haven't got any drawings yet. Worst case i'll just start following the wires to see where everything goes. For the upgrades i'm generally thinking about going with 3 AGM group 27 batteries probably Odyssey. new smart charger probably Blue Sea P12 7531, 2 Blue Sea 7610 Si-ACR's, possibly changing the switches out to Blue Sea 5511e (off-on-combine) (this would require some rewiring of the switches and allow battery combining but eliminate the ability to isolate a single battery which I think it does now) (probably mitigate concerns about battery isolation by using high quality batteries). The switch change just makes everything easier to understand as the 4 way switches are mass confusion and in a situation where i needed to actually combine or isolate batteries i don't want to have to read a wiring diagram to figure out how to configure the switches. although if i do this right it should just be on or off 99% of the time.

Concerns:

1. The generator and both engines all have alternators that would/could feed charge to the batteries all at the same time if all were running. At minimum both engines would be charging at the same time if the generator was off. ACR's would combine the batteries but I believe this is all ok as each of the alternators would self regulate their output. Correct?

2. If running the generator and charger at the same time would the generator DC output through alternator interfere with the charger if running the charger from the generator AC output? The Si-ACR's have a disconnect feature controlled by the P12 charger which would force disconnect the port and starboard batteries from the generator charging system but still output from the p12 to the batteries directly, but the house/generator battery would get both inputs and may fight with each other and never really charge this battery?

3. Maybe just only use the charger on shore power? This eliminates #2 above and would allow the generator to feed alternator charge to all 3 batteries through the ACR's while at anchor on generator power?

4. Switch configuration when running, coving out, shore power?

5. Want to make sure i don't run down the starting batteries if hanging out on battery power only. (again i think the ACr's would take care of this by disconnecting the port and starboard batteries as the voltage began to drop) Right?

6. What am i not thinking about?

Our primary use is cruising as well as coving out we don't overnight on the boat. When hanging out on the water we run the stereo system, fridge and A/C so usually fire up the generator for that. or sometimes just hang out and run stereo only no generator just battery power.

The bordem of winter always leads to me spending $$$! At worst something to think about!

[jwill323]

battery panel.jpeg

[jwill323]

IMG_3686.jpeg

first rough draft of new layout. I realize a few things are missing like fuses at the battery connections, an additional ACR and the bilge pump to the constant power side, but this is a rough first draft.

[jwill323]

IMG_3687.jpeg

Revised drawing hopefully a little better

IMG_3688.jpeg

Charger / ACR / Battery Detail