How Does a Resistive Transducer Work?

A resistive transducer works by changing its level of electrical resistance depending on the condition of another object or process, allowing any changes to be detected without direct observation of the condition or object. There are many types of resistive transducers, from those that measure movement to those that measure temperature, strain, pressure or some other quantity. They have a wide variety of structures to accomplish these goals.

All resistive tranducers rely on measuring the resistance to electrical currents. The variations in this resistance can indicate many different events. One simple type is the sliding contact transducer. One end of this transducer is fixed. A slider is attached to a moving object and moves along the transducer. A current is passed through, and the resistance in the transducer to the current grows the further away from the fixed end the object moves.

Thermistors are another type of resistive transducer that measures temperature. They usually rely on certain semiconductive ceramics, such as metal oxides. The electrical resistance of these materials varies depending on temperature. The resistance is easily detected and can indicate the temperature of the semiconductor. The thermocouple, a resistive transducer that uses two dissimilar materials placed end to end, is another type of temperature sensor.