Hysteresis refers to the behavior of a transducer to produce different output values for a common input point depending on whether applied input is increasing or decreasing.

Hysteresis is due to the behavioral patterns of metal crystals, which expand and contract differently. As applied pressure on a transducer increases, the non-linear representation of the transducer’s output traces its true sensitivity curve. But as applied pressure on a transducer decreases, the non-linear representation of transducer output results in a different sensitivity curve.

Hysteresis is then the greatest difference between output readings for a common input point, one reading obtained while increasing from zero input, and the other while decreasing from full scale output. The deviation is expressed as a percent of full scale. An example of hysteresis for a transducer is ±0.10% F.S.