Glossary · Sensors and measurement
Sensitivity
Also known as: Sensitivity of a measuring system
German: Empfindlichkeit
In metrology, sensitivity is the quotient of the change in an indication of a measuring system and the corresponding change in the value of the quantity being measured, for example millivolts per newton.
- Sensors
- Standards
In one sentence
Sensitivity is the change in a sensor's output per change in the measured quantity, e.g. millivolts per newton or per unit of acceleration.
Example
A piezoelectric accelerometer has a sensitivity of 100 mV/g, which the vibration monitor needs to convert voltage into acceleration.
How it applies
- Engineering: Sensitivity links output and input and is needed for scaling. It can depend on temperature and frequency; datasheets state these dependencies separately.
- Commissioning: For sensors with individual calibration values, such as accelerometers or load cells, the stated sensitivity of the specific sensor must be entered in the evaluation device.
- Operation: In switching sensors, sensitivity is often an adjustable setting that changes the detection threshold. This is a different, everyday use of the word.
- Documentation: Record individual sensitivity values with the serial number. Replacement instructions must say that the new sensor's value has to be entered, otherwise readings are wrong without any error message.
Sensitivity vs. resolution
Sensitivity is the ratio of output change to input change. Resolution is the smallest input change that produces a detectable output change. High sensitivity helps resolution, but noise limits it.