Glossary · Sensors and measurement
Steady-state accuracy
Also known as: Steady-state error, Static accuracy
German: Stationäre Genauigkeit
In measurement and control, steady-state accuracy describes the remaining deviation between the output and the true or desired value once all transients have died out; in control loops, it corresponds to the steady-state control error.
- Sensors
In one sentence
Steady-state accuracy is the remaining deviation between output and true or target value after all transients have settled.
Example
A temperature controller with only proportional action leaves a steady-state error of 2 K; adding integral action removes it.
How it applies
- Measurement: Steady-state accuracy applies to constant input values after the sensor has settled. Dynamic errors during fast changes are specified separately, for example as response time.
- Control engineering: In Closed-loop control, the steady-state error depends on controller structure; integral action removes it for constant setpoints and disturbances, while proportional-only control leaves an offset.
- Commissioning: Checking steady-state accuracy requires waiting until the process has settled. Acceptance tests should state the settling criteria.
- Documentation: State whether accuracy figures in specifications and test reports are steady-state or dynamic values, and under which conditions they were measured.
Steady-state vs. dynamic accuracy
Steady-state accuracy describes the settled state. Dynamic accuracy describes how well the output follows changes, which depends on response time, damping and bandwidth.