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Hysteresis -
This is a measure of deviation in the output when passing through an input point
from two different directions. If a pressure transducer has zero pressure applied, then 10 PSI, then 22
PSI, then 10 PSI, the difference between the two 10 PSI readings would be a measure of the pressure
hysteresis of the transducer. Pressure transducers can also have temperature hysteresis errors.
Sometimes hysteresis is lumped in with other non-repeatability errors.
ACCURACY -
Accuracy is a measure of how closely the sensor's output matches the "true"
value of the parameter being sensed.
PRECISION -
Precision is a measure of the repeatability of the sensor. It will most always
be better than the accuracy of the sensor.
RESOLUTION
- The resolution of a sensor is the smallest change in the input that is
reflected in the output. For digital sensors it also refers to the smallest increment of the output. This may
be greater than or less than the sensor's resolution with respect to its input. Greater resolution does not
imply greater accuracy. Resolution and Accuracy are two independent variables. The advantage of
resolution in excess of accuracy is that changes in the input parameter can be detected and tracked.
