If the charging voltage is much higher than 14.0 it may overcharge the battery and significantly shorten the life of the battery. All it takes to drop the charging voltage is a resistor inline to the battery to cause some voltage drop. Solar pannels produce more voltage the brighter the sun is AND the lower the temps are. Hot, sunny summer days are not the best charging days; cold bright sunny winter days are when you will see the highest voltage from the pannel. The logic circuit isn't complicated to manage the voltage according to the charge state of the battery. i.e. charge at a higher voltage when the battery is weaker, and trickle charge when the battery is almost or fully charged. This will maintain battery health and longevity the easiest. Does this help?
Luther ~Tom, ~ ~You'll need to get output of right around 13.0 volts. Too low, no ~charging will happen (might even drain battery), I don't think that too ~high will be a problem given that the amperage will probably be low. If ~the panels don't put out more than 13 volts, you'll need to find a ~clever way to step up the voltage. ~ ~After that, maybe an efficient set of diodes to keep current flow going ~in correct directions, and maybe a fuse for safety on the positive ~side.. ~ ~Very respectfully, ~/s/ ~Meade Dillon ~Charleston SC ~'87 300TD 287k miles ~'85 190D 2.2 5 spd 106k miles ~'85 300TD Euro 5spd 327k miles *sold* ~ -- Luther KB5QHU Alma, Ark '83 300SD (231,xxx kmi) '82 300CD (159,222 kmi) '82 300D (74,000 kmi) needs MAJOR work
