Glossary of terms and usual concepts in metrology
MIC - media reporting on the quality
Control dimensional
Technological activity, dedicated to the collection of information and its further processing, aiming to the conformity assessment industrial products with their technical specifications- dimensional.
Measure
Appropriate means to assess the quotient that is to divide the magnitude of a feature, the unit for assign a numeric value: k = M / [u] Unit - wide agreement recognition on the size of a feature, which by tradition and mainly by its invariability and repeatability are imposed as a reference in the process of measuring.
Terms and concepts associated with the calibration
Pattern
Sample of magnitude of a feature in certified relationship with the international pattern, credited to calibrate MIC, according to the powers of the class of accuracy to which it belongs.
Traceability
Uninterrupted chain of registered calibrations, which ensures the connection between a MIC and the pattern of the unity of international recognition for the feature to be measured.
Calibrate
Register and process and compare the output of a MIC information, in several points along its scale, with the confidence of a pattern value (or combinations of patterns) that has (n) certified traceability, with the order to evaluate its uncertainty.
Uncertainty
Narrow band, with symmetrical position respect to the value of output of a MIC, in which the probability (p) of the true value of the magnitude measured, is higher than the value limit, corresponding to the class of proposed coverage.
For k = 2 p > 95%
Result the calibration
Graphical representation of the mathematical relationship between the values indicated by the instrument or the subject system to the calibration and the certified value of the reference pattern, involved as mesurando.
Adjustment an instrument
Action of improvement that is to modify components physical or through programs result in output of a instrument, in order to compensate for the calibration curve. They are removed the systematic errors.
Terms and concepts associated to a instrument
StabilityCapacity of a measuring instrument of preserve their metrological in time.
Maintainability
Expresses the probability that, under the conditions of use and maintenance, the team retain its ability to perform the functions required.
Concepts associated with a process of measurement
RepeatabilityTerm that defines the range of uncertainty of the results of the repetitive measurement of the same mesurando, under the same conditions.
Reproducibility
Term that defines the interval of uncertainty the results of the repetitive measurement of the same mesurando, bass changing conditions.
| Repeatability - results on: | Reproducibility- Results on: |
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Expression of the result
- When the figure that it follows immediately to the last figure to keep is less than 5, the last figure does not change
- When the figure that it follows immediately to the latest figure to conserve is equal to 5 and is followed by at least one non-zero, the latter figure to keep figure is increased by one Unit; But if it is not followed by any other number or if it is only followed by zeros, the latter figure to keep does not change if it is even, and increases by one if it is odd.
- When the figure that it follows immediately to the latest figure to preserve is greater than 5, the latest figure increases by one.
- Rounding should not be conducted in several stages, but only one time.
Example: move from five decimals to three
| 7.90746 | -> | 7.907 |
| 7.90850 | -> | 7.908 |
| 7.90950 | -> | 7.910 |
| 7.99962 | -> | 8,000 |
Environmentalconditions in metrology according to DKD - 6
| Parameter | Unit | Nominal value | Tolerance | Follow-up |
| Temperature | o(C) | 20 | ± 2 | Mercury in glass thermometer |
| Relative humidity of the air | % | 50 | ± 15 | Hygrometer |
| Lighting | LX | > 400 | Thermometer |
