№3/2021 year Technical science and innovation 198
combination of primary and secondary measuring conductors, which are close to accuracy and
metrological reliability, but differ in the sensitivity to exposure to the quantities that make up
the error component. Bourdon tube with a pressure sensor is an example. The critical
component of the error results from residual deformations that occur during operation. The
pressure is measured by the motion of the free end and additionally by the motion of the
intermediate point. The displacement ratio of these points is used as a diagnostic parameter
characterizing the critical component - errors. The level of critical components in the sensor is
automatically controlled and the probability of the error being exceeded by other components is
very low.
Metrological self-monitoring should form an assessment of the status of the
measurement result. Depending on the functions performed by the sensor, the results of
metrological self-monitoring may include:
1.
Assess the error or an important component of the error (including correction, if
any);
2.
Evaluation of the remaining metrological resource;
3.
Archive of metrological self-monitoring data.
In addition to the features required by the state standard, the following features should
be provided in the documentation for intelligent sensors to eliminate the possibility of unfair
competition:
1.
The method of used metrological self-observation;
2.
Critical components of error;
3.
The time interval between self-monitoring procedures;
4.
Availability of automatic error correction function;
5.
Limit values of measurement error or critical components for which automatic
correction is performed;
6.
Additional functions performed on the basis of the results of metrological self-
monitoring, such as self-correction in case of a defect or forecasting of the
remaining metrological resource.
Self-correction can be accomplished by changing the data processing program and
deteriorating the metrological properties.
The recommended maximum calibration interval should be proven and determined at
the stage of intelligent sensor development, taking into account the limitations of the selected
metrological self-monitoring method.
An estimate of the remaining metrological service data calculated over a sufficiently
long period of time based on the results of metrological self-monitoring can be used to
determine the next inspection or calibration time.
RESULTS. Precise planning of the process of purchasing a new measuring instrument
based on the data analyzed above can help prevent many errors. It is necessary to plan actions
and determine the results to be achieved at each stage. In the future, it is necessary to follow to
the planned plan and not miss a single step - so there is no risk of losing important things.
Based on our own experience, we recommend the following steps while choosing a new device.