Static sensitivity, in the context of measurement and instrumentation, refers to the ratio of the change in the output of a measurement instrument or sensor to a corresponding change in the input quantity being measured. It is an important characteristic of an instrument as it determines how effectively the instrument can detect and respond to changes in the measured quantity.
Mathematically, static sensitivity (S) is defined as:
=
Δ
Δ
S=
ΔI
ΔO
Where:
S is the static sensitivity of the instrument.
Δ
ΔO is the change in the output of the instrument.
Δ
ΔI is the change in the input quantity being measured.
Static sensitivity essentially quantifies the instrument's ability to translate changes in the input into proportional changes in the output. A higher static sensitivity value indicates that the instrument is more responsive to changes in the input, while a lower value indicates less responsiveness.
For example, consider a temperature sensor with a static sensitivity of 0.5 V/°C. This means that for every 1-degree Celsius change in temperature (
Δ
=
1
°
ΔI=1°C), the output voltage of the sensor (
Δ
ΔO) changes by 0.5 volts.
It's important to note that static sensitivity is a linear approximation and is most accurate within a certain range of input values. In practice, some instruments might exhibit non-linear behavior, meaning the relationship between input and output is not strictly proportional. In such cases, the concept of dynamic sensitivity might come into play, which considers changes in sensitivity over a range of input values.
In summary, static sensitivity is a fundamental parameter in measurement and instrumentation that characterizes an instrument's ability to accurately respond to changes in the input quantity being measured.