Glossary · Sensors and measurement
Resolution
Also known as: Measurement resolution
German: Auflösung
In metrology, resolution is the smallest change in a measured quantity that causes a perceptible change in the corresponding indication. For digital systems, it is often given in bits or as the value of one digit or increment.
- Sensors
- Standards
In one sentence
Resolution is the smallest change in a measured quantity that produces a detectable change in the output; it does not equal accuracy.
Example
A 16-bit analog input resolves a 0 to 10 V signal in steps of about 0.15 mV, but the sensor feeding it is accurate only to 10 mV.
How it applies
- Engineering: The effective resolution of a chain is limited by its weakest element: sensor, transmitter, analog-to-digital converter or the data type used in the controller. Noise can make the last digits meaningless.
- Commissioning: Displaying more decimal places than the resolution or accuracy supports suggests false precision. Set HMI formats accordingly.
- Motion control: Encoder resolution in increments per revolution limits position and speed control quality, together with mechanics.
- Documentation: Do not present resolution as accuracy in datasheets or product texts. State both separately with units.
Resolution vs. accuracy
Resolution is the smallest detectable step. Accuracy is how close the value is to the truth. A high-resolution instrument can still be inaccurate. Where an interface transfers values as integers, document the scaling factor so that receivers can reconstruct the resolution.