Potentiometers A potentiometer is simply a variable resistor that can be controlled by the user. Potentiometers accomplish this by having three terminal resistors forming and a load that connect the potentiometer and the voltage source in one loop and the potentiometer and the load in another. Potentiometers have a wide range of uses, ranging from CD players to Servo mechanisms. How Does a Potentiometer Work? A potentiometer has 3 pins. Two terminals (the blue and green) are connected to a resistive element and the third terminal (the black one) is connected to an adjustable wiper. The potentiometer will work as a rheostat (variable resistor) or as a voltage divider. Rheostat To use the potentiometer as a rheostat, only two pins are used: one outside pin and the center pin. The position of the wiper determines what quantity resistance the potentiometer is imposing to the circuit, as the figure demonstrates: If we have a 10kΩ potentiometer, it means that the maximu...