10 Amp Solar Charge Controller - CDT-C10 Regulator 12/24V #35010 The most important function of the solar panel is to charge the battery and provide battery status which is vital to the user. Therefore, battery monitoring is the primary function of our controllers. Our "smart" controllers are designed to protect and monitor your battery. A charge controller is required to prevent over-charging battery and short circuit the solar panel diode under load. Will work with 12V or 24V system Up to 150W panel for 12V