The charge controller functions as a voltage regulator, carrying the energy from the solar panels to the batteries at the correct voltage level. They help prevent the batteries from overcharging, short-circuiting, and block reverse currents.
Renogy offers various types of PWM and MPPT charge controllers, available in different amperages to suit your applications. Pulse Width Modulation (PWM) charge controllers are good low-cost solutions for smaller systems that run on a parallel connection. Maximum Power Point Technology (MPPT) charge controllers maximize a panel's output under all weather conditions and work best with a series connection.