Sensor basic tutorial knowledge-3
Sensor linearity
Typically, the actual static characteristic output of the sensor is a bar curve rather than a straight line. In actual work, in order to make the meter have a uniform scale reading, a fitting straight line is commonly used to represent the actual characteristic curve, and the linearity (non-linearity error) is a performance index of this approximation. There are several ways to select a fitted line. For example, the theoretical straight line connecting the zero input and the full-scale output point is used as the fitted straight line; or the theoretical straight line with the smallest square of the deviation from each point on the characteristic curve is used as the fitted straight line, and the fitted straight line is called the least squares method. The linearity for WBI414F23 is 0-120% of nominal input.
Sensor sensitivity
Sensitivity refers to the ratio of the change in output Δ y to the change in input Δ x under steady-state operation of the sensor. It is the slope of the output-input characteristic curve. Sensitivity S is a constant if there is a linear relationship between the sensor's output and the input. Otherwise, it will change as the amount of input changes.
The dimension of sensitivity is the ratio of the dimensions of the output and the input. For example, for a displacement sensor, when the displacement changes by 1 mm and the output voltage changes to 200 mV, the sensitivity should be expressed as 200 mV/mm.
When the output of the sensor and the amount of input are the same, the sensitivity can be understood as a magnification.
Increase the sensitivity and get higher measurement accuracy. However, the higher the sensitivity, the narrower the measurement range and the worse the stability.
