The optical sensing mechanism of the Nidec Copal Electronics JT22 and JT30 contactless potentiometers give these products a long rotational life: 100 million revolutions for the JT22 series and 200 million revolutions for the JT30 products. These sensing potentiometers have a very low torque, and can be used in wide range of applications, such as detecting the amount of wire material in a winding machine, a paper feeder in a printer, and in equipment that requires high levels of accuracy, such as semiconductor manufacturing equipment.