How would you wire this battery setup?

[Bohans]

Hi Everyone

I am planning on taking a new boat in the New Year all going well and wanted your thoughts and experiences as to how you would wire the battery, alternator set up for maximum redundancy and efficiency.

Here is what I have:

1. 12 volt house bank: Deep cylcle calcium batteries at 800amp (4 x 200)
2. 2 x 12 volt Start bank: 1 x 1000cca start battery on port and 1 x same on starboard. These start the gensets and the main engine on their side of the boat.
3. 24 volt inverter bank: 400amp hour bank. Has its own charger.
4. Main engines with 12 volt alternator each which is wired to the house bank and start bank. Not sure how they are wired as yet to charge independent banks.
5. Gensets 20kva with non-working 12 volt alternators. These will be functional and are wired at this stage to the engine start banks.
6. House battery charger at 60amp dedicated to house bank.
7. Xantrex (non-working,,,ofcourse) 40 amp true charge wired to both start battery banks.

Here is what I want:

Charging for the Inverter bank when main engines are being run. This cuts down on genset run time when underway. Makes more efficient use of main engines.

Charging of house bank when underway through main engine alternators.

Use the Genset alternators to charge something...preferably engine start banks and house bank at same time.

My thoughts:

1. Replace 1 x Main engine alternator with 180 amp alternator (already has double pulley and current alt is 105 amp model Leece Neville.) Wire the 180 amp alt to the house bank and engine start banks via a 3 way Alternator Distributor system such as the ones from Defender.

2. Replace 1 x Main engine 12 volt alternator with a 24 volt alternator to charge the Inverter bank while underway.

3. Use the two main engine alternators (both 105 amp) for the gensets and wire through another alternator distributor to charge the house and engine start banks at the same time.

So now tell me, what would you do? Is there a better way to achieve minimal genset run time and more efficient use of the alternators etc when already running various motors.

Thanks

Bo

 

[Keysdisease]

Take a look at #3:

http://www.perko.com/images/catalog/pdf/Fig 8501-8504 Inst (8500INS1).pdf

Charging the 24V bank from the main engines 12V alternators will be challenging.

 

[Ski in NC]

Adding a 24v alt to one of your main engines sounds like a key feature to get what you want. The 12v on the other engine can be distributed to the various 12v banks via a combiner setup. Alts on gensets often disabled on purpose, as if you are going to run it, it will make plenty of AC to run a proper charger.

 

[Bohans]

yes thanks forgot to mention I am adding a 24,volt alt to one of the mains closest to the inverter bank.

 

[O C Diver]

I would take a long hard look at the condition of your batteries and the quality of your inverter. Seems like combining the amps of both the inverter and house bank if you were replacing batteries and the inverter would make for a very nice, much simpler setup. Obviously, this requires making the inverter and it's batteries 12 volt. On my boat (single engine) I now have a 900 amp golf cart battery back, 30 amp inverter / 160 charger, and a second alternator (Leece Neville 220 amp with 3 stage regulator) for house and inverter bank. The engine and genset have their own batteries and alternators. If I'm running the genset, I can easily take the extra capacity of the genset to charge the battery bank through the inverter/ charger. Also have a battery switch that allows combining of the house and engine battery, to either jump start the engine or charge either battery in the event of an alternator failure.

Ted