10Ah Dual Battery Charge Controller•Can charge two batteries simultaneously & can work on both 12v or 24v systems•This controller is for off-grid solar systemsThis controller is for off-grid solar systems and has the additional functionality that it can charge two batteries simultaneously and can work on both 12v or 24v systems. The charging process has been optimized for long battery life and improved system performance. The comprehensive self-diagnostics and electronic protection functions can prevent damage from installation mistakes or system faults. Reverse current protection. Unique dual battery charging function. Efficient Series PWM charging, increases battery lifetime and improves solar system performance. 12/24V automatic recognition. Overload protection Open circuit protection. Lightning surge protection. Deep discharge protection. Charge current protection up to 10A. All solar panels (except the 5w &10W) require a voltage regulator to ensure that the battery is not overcharged. We recommend the this controller for panels up to and including 150w.