Static performance characteristics play a significant role in electronic instruments as they are used to measure process conditions. They are obtained by one or another form of calibration. Following are few such characteristics:

• Accuracy

  • It is the degree of exactness of a measurement compared to the expected or desired value

  • High accuracy is always preferred as erroneous measurements in electronic instruments can lead to adverse effects

  • It is often measured in percentage

• Precision

  • It is the measure of consistency or repeatability of measurements i.e. successive readings in an instrument should not differ

• Sensitivity

  • It is the ratio of change in output (or response) of the instrument to change in input or measured variable

  • A higher sensitivity indicates that the system can respond to even the smallest input

In contrast, dynamic characteristics are determined by subjecting the sensing element of the instrument to some unknown and predetermined variations in the measured quantity.