ric wrote:
I have two dual purpose 12v wired in parallel on the engine side. Two 6v deep cycles wired in series on the house side.
Why 6v? Cheaper, lighter. Two 230ah 6v give me 230ah of 12v. At 65lb each that's 130lb for 230ah and $100 each for a total of $200. I can safely use 85% of the capacity of a 6v cell with no damage what so ever so I have a safe 195 amp hours of power. To size that in 12v batteries let's use Optima Blue Top marine deep cycles for example. The biggest/baddest they sell is the D31M. It's 60lb and 75ah. $270 each. Safe discharge limit of 50% or around 38 amp hours. It would take 5 Optima Blue tops to equal the power of two 6v cells. It would weigh 300lb and cost $1350!! 12v cells on a house side is wasteful and pointless.
The house side is independent from the boat but in the future might be connected via. isolator to gain some free charging while the engine is running.
And this has what to do with the topic? other than 230AHs of battery(s) and 20 amp charger would take about 10 hours to charge. Thats if there fully discharged! But you don't know that and you make these comments. I think you just like to hear your self talk/write. If you know how to wire it up right and know how to use it, 12volt batteries will do the job as well as 6volt ones. And you have proved that you don't know and JUST think you know.
Hint for you, a 10a charger will work for you as well. The chances of you fully discharging them is slim. Not to mention, as soon as you start your engine they will be charging anyways. Have you replaced your alternator?