Originally Posted by rkelley712
thanks for the advice...one question is it better to have to 2 12 volts or 2 6 volts with the approximate same ah
It works out pretty much the same as 6 volt batteries have a higher ah. Most 12 volt batteries have 100ah and most 6 volt batteries have 200-230ah. When you connect two 12 volts in series, your ah doubles so you have 200ah. If you take two 6 volts and connect them in series, you double the voltage but the ah stays the same, so two 6 volt would still give you 200-230ah. Where the 6 volts have an advantage is they are built with heavier plates inside and will hold a charge longer and last longer than 12v batteries if maintained properly. You also have to remember that even if you have a total of 200ah, you really only have 100ah of use as you really donít want to take them down below 50% charge or you start causing damage, most 6 volts you can safely take down to 40% charge. The Harris batteries you have are not very good batteries but you say you are getting 36 hours out of them with a residentialÖ..thatís actually pretty good IMO, better AGM batteries like Lifeline would probably get you a little more but if you are not happy with that you would have to jump to Lifepo4 batteries. The advantage of Lifepo4 batteries is you will have 12-13 volts clear down to about 10% charge left where on a flooded or agm, your voltage drops with use and you have about 12 volts at 50% charge left. Lifepo4 batteries also charge up a lot faster than flooded or agm.