Resistance based electrical transducers

Potentiometer device

Principle of operation - Movement of a slider ( by external force acting on it) causes the resistance to change in the potentiometer and subsequently the bridge circuit Application - Pressure, Displacement

Resistance Strain gauge Principle of operation - Expansion or compression of the wire alters the resistance of the element, Application - Force, torque, displacement

Pirani gauge or hot wire meter Principle of operation - Temperature changes have effect on the resistance of the material, So when a cool gas passes through a normally heated wire, the resistance changes. Application - Gas flow, Gas pressure

Resistance Thermometer Principle of operation - Temperature coefficient is the phenomenon where a change in temperature effects the resistance, metals have positive temperature co efficient where in the rise in temperature leads to rise in resistance Application - Temperature,Radiant heat

Thermistor Principle of operation - Working with the temperature coefficient phenomenon, metal oxides have negative temperature coefficient, where temperature increase leads to decrease in resistance Application - Temperature, flow

Resistance hygrometer Principle of operation - Moisture content alters the resistance of the conductive strip Application - Relative humidity

Photoconductive cell Principle of operation - The resistance of the element changes with incident light. Application - Photosensitive relay