The Accuracy In metrology, it describes how close a measured value is to the actual or true value of a measured quantity. It is one of the most important parameters for evaluating measuring instruments, sensors, and measurement systems.
In accordance with the metrology standard DIN 1319-2 Accuracy is the degree to which a measurement result approximates the true value of the input quantity. The smaller the deviation between the measured value and the actual value, the more accurate the measurement.
In practice, however, the true value of a physical quantity usually cannot be determined directly. Instead, highly accurate reference systems and calibration standards are used. The value determined using these references is considered a sufficiently accurate approximation and serves as a benchmark for assessing measurement accuracy.
Accuracy Classes of Measuring Instruments
Many measuring instruments are used in so-called Accuracy Classes classified. These specify the permissible error limits within which a measuring instrument operates. The higher the accuracy of a measuring system, the smaller the possible measurement deviations.
Actual measurement accuracy is influenced by various factors, including:
- Sensor Specifications
- Signal Processing Quality
- Resolution of the measurement system
- Temperature and Environmental Factors
- Calibration Status of the Device
- Measurement Range and Operating Conditions
Accuracy in Industrial Measurement Technology
In modern measurement, testing, and automation systems, high accuracy is crucial for reliable results. It forms the basis for quality control, process monitoring, research, development, and safety-critical applications.
Especially when measuring temperature, pressure, force, voltage, current, or vibrations, even small measurement deviations can have a significant impact on the evaluation of processes or products.
Accuracy, precision, and resolution—they're not the same thing
The terms "accuracy," "precision," and "resolution" are often confused, but they describe different characteristics:
- Accuracy describes how close it is to the actual value.
- Precision describes the repeatability of measurement results.
- Resolution describes the smallest detectable change in a measured value.
For example, a measuring device can have high resolution without being particularly accurate.
Benefits of High Measurement Accuracy
- Reliable measurement results
- Improved Process Control
- Higher product quality
- Early Error Detection
- Comparable and reproducible measurements
- Ensuring Compliance with Standards and Specifications
Accuracy is therefore a key parameter in measurement technology and plays a decisive role in determining how meaningful and reliable measurement results are in industry, research, and development.