If your battery charger produces a charge rate greater than 12 volts it may damage your batteries. You should be sure your batteries are fully charged before leaving for a trip.
How To Charge Your Rv Battery 12 Steps With Pictures Wikihow
How to charge rv batteries in parallel. The negative terminal is labeled. Once you have the batteries wired properly in parallel you will need to connect the 12 volt power wire from the trailer 7 way connector to the positive wire on the first battery. This connection will help maintain the batteries when the vehicle is running but will not charge them sufficiently from a discharged state. Connect the negative black wire from your battery charger to the negative terminal of one of the 12 volt batteries wired in parallel. Making sure your twelve volt 12v batteries are hooked up in parallel will ensure proper cycling and charging. Do you continue to add to the string in a linear fashion figure 1.
Yep electrically speaking that works. When asked how to charge batteries in parallel people commonly reply connect the positive to positive and negative to negative. 7 plug in the charger and turn it on. Attach the rv battery charger to the battery. Connect the positive side to the red connection first and then attach the negative side of the battery with the black connection or clamp the black connection to a metal piece to ground it. Properly connecting your rv batteries is an important and often overlooked step.
But what if you have an rv for example and need to add 3 or 4 or 8 batteries in parallel. Therefore both configurations can be charged by any 12 volt battery charger by simply connecting the chargers red cable clamp to the plus 12 volt terminal lead and the black or ground cable clamp to the negative terminal as shown here. Twelve volt batteries wired in parallel must be charged at 12 volts.