Question 30Electricity & Electronics - Assistant Engineer

The correct answer is C) varying the voltage applied to the motor. The speed of a series wound winch motor is controlled by varying the voltage applied to the motor. Series wound motors have a direct relationship between the voltage and the speed - increasing the voltage increases the speed, and decreasing the voltage decreases the speed. This allows the operator to precisely control the winch speed by adjusting the voltage, which is a common method for controlling series wound motors used in winches and similar equipment. The other answer choices are incorrect because: A) overcurrent protection devices protect the motor from damage, but do not directly control the speed; B) the weight of the load does not directly control the motor speed; and D) a hydraulic governor would control the speed of a hydraulic motor, not an electric series wound motor.