APTECHDEALS Electronic Speed Controller (ESC) for Brushless DC Motor & Quad Rotor (Quad Copter) - 30Amp (make DYS) (blue)  (Blue)

Introduction On a quad copter, the flight control board's firmware monitors measurement devices like gyros and accelerometers along with pilot stick inputs and sends signals to the ESCs attached to each the four motors. The ESCs use these inputs received from the flight control board to deliver the power required to control the speed of the motors. Each ESC has a processor, firmware and other electronics that manage this task by rapidly switching the power to the motor on and off.