12VDC setup on 44 Sedan Bridge

Batteries on the 44 Sedan Bridge are setup with 2 batteries in parallel for each engine, 4 in total and 2 for the bow thruster. The boat has no dedicated battery for the generator or a separate house bank. From a diagram in the manual it appears the cabin 12VDC devices may be powered primarily by the port bank while helm electronics from Starboard. Other items appear to be split between both. Does this sound right? You could still potentially drain down the all 4 of these batteries and you would be unable to start either engine or the generator. I have noticed that the 44 Sundancer does however have a separate battery for the generator. The rest of the setup remains similar though. Has anyone been able to add a dedicated battery for the genny on the Sedan? If so what did you need to do the have the generator charge the battery as well and also not mess up the existing electrical setup since everything seems to go through the large electrical disconnect box in the engine room first. Also is there anyway one could add a separate house bank on this boat or is all you can do is increase the size of the 2 engine battery banks (maybe only port) if you need increased capacity?

My last boat had dedicated batteries for the genny, each engine, and a large bank for just the house. Liked this setup much better.
The engine banks and house were either charged by the main engines or the house battery charger. The genny battery was charged by the genny when it was running. The house bank was a large deep cycle bank that also powered the integrated Inverter.

Hopefully a few of you will have gone through this already and have some advice.

I installed a combiner off the port bank to keep a dedicated generator battery charged. Then, I wired the generator to that battery for starting duty. Very cheap insurance.

i expanded my port bank to 4 group 31's. My starboard bank is still 2 group 31's. The thruster batteries are their own dedicated system.

I explored many options to dedicate a house bank. It's do-able, but wasn't worth the hassle.

So I'm on the right track that most 12VDC draw in the boat for lights etc comes off the port bank and that would be the one to expand for any increased capacity when not plugged in.

Does the generator not have the ability to charge it's own battery? My last boat did. I take it you had to rewire the connection from the large box with all the remote solenoids. Does the generator battery solenoid still turn on power to your new dedicated battery now?

Yes, the port bank is mainly set up as the "house" with minimal routine draw on the starboard bank (except as you've noted: helm electronics, etc.). So, the thinking I'm guessing by Sea Ray electrical engineers was that you can always use the starboard bank to start the starboard engine and/or generator and then use the "emergency" switch at the helm to parallel the two to start the port engine if needed. And of course the generator will charge all the batteries once running.

I did have this same boat and I likewise was never fond of this setup. That said, I was never able to not start something when the port bank died (sorry for double negative). One alternative I considered was to add another battery in parallel to the port bank. Although the option I chose was to put all AGMs in across the board (Optima Blue Tops) and I never had any problems with it, but I agree that the setup is odd.

Ray K said:

So I'm on the right track that most 12VDC draw in the boat for lights etc comes off the port bank and that would be the one to expand for any increased capacity when not plugged in.

Does the generator not have the ability to charge it's own battery? My last boat did. I take it you had to rewire the connection from the large box with all the remote solenoids. Does the generator battery solenoid still turn on power to your new dedicated battery now?

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All the wiring changes were done in that gray solenoid box (if my memory serves me). The generator feeds the battery charger AC that charges my batteries. I suppose I could feed the generator battery a charge when the generator is running. It was just easier to me to use a combiner off the house bank that always keeps the genny topped off (alternators charge that bank as well). It's cheap insurance. I also have a combiner flowing from the port bank to starboard bank to ensure that one stays charged in the event I lose the starboard alternator. If the port alternator fails, I can use the parallel switch at the helm to keep the port side powered. May not have been totally needed either. I am a fan of redundancy.

All solenoids are intact and functional.

Converse48 said:

.... One alternative I considered was to add another battery in parallel to the port bank...

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I agree with everything above and found that adding 3rd batter to the port bank was the easiest solution, as there was nothing needed to be changed at the battery charger side. I did this minor upgrade couple of years ago and it works like a charm. As Tim pointed out, the STBD bank stays fairly well charged due to minimal load, so you can always fire it up first and then use emergency switch to assist the PORT side. However, the better approach would be to use crossover switch and fire up genny and recharge all the batteries.

I also don't get it why would SR have very logical setup of having dedicated battery for genny on some models and go away from this on others. It doesn't make sense to me.