This boat has a large bank of Trojan flooded batteries and the alternator, with smart regulator, is sized at 20% of the banks Ah capacity (cold rating).


With the smart regulator it took approx 75 minutes, at full output (though temp protected), of continually rising voltage during bulk, for the batteries to attain the absorption voltage limit of 14.8V. Once at 14.8V the voltage was held steady by the regulator. By sizing your alternator to 20-25% of the banks capacity, when its hot, your can rather drastically reduce the bulk charge time.


This is what a healthy charge voltage profile looks like. The other bank previously shown never exceeded 13.81V in 1.5 hours yet this bank attained 14.8V at 75 minutes and then continued to hold the proper absorption voltage for these Trojan Batteries. These batteries are in their 8th year.