String Potentiometer

A string potentiometer, sometimes also known as a string pot, a draw wire senor, a string encoder or a yo yo pot, is a cable actuated position sensor used to detect and measure linear position and velocity using a flexible cable and a spring-loaded spool. In order to take measurements, the transducer's body is mounted to a fixed surface and the stainless steel cable is attached to the movable object. As the object moves, the transducer produces an electrical signal that is proportional to the cable's linear extension or velocity. This signal can then be sent to a display, a PLC or data acquisition system.