The purpose of organizing an effective measurement process is to provide an optimal combination of the measuring instruments quality and the quality of measurements. To increase the reliability of measurements in industry and to reduce the cost of confirming their metrological compliance, methods of instant control of measuring instruments metrological characteristics are proposed. Attention is focused on the dependence of the level of costs on the accuracy and reliability of measurements. The last are based on decisions devoted to the operating processes.
It is ensured the certain metrological autonomy of individual industries, which allow reducing costs for the metrological maintenance of production while the necessary level of unity, accuracy and reliability of measurements is justified.
In the general case, depending on the place of application in the measurement, methods for increasing the accuracy of measurements can be divided into two groups: - methods for increasing the accuracy of measuring instrument; - methods for increasing the accuracy of measurement results. The first group is characterized by stabilization of the transformation function of measuring instruments. It is also divided into two methods categories. The first of them is the improvement of measuring instruments aiming the increase of the measurements quality. The second one is increasing the quality of measuring instruments. There exist the ways to stabilize the transformation function: - design and technology that form the best protection against interference. They are the application of a more advanced elemental base; structural-algorithmic stabilizing the transformation function of measuring instruments, and results processing. The second group combines the methods of stabilizing the output signal of measuring instruments. Stabilization is achieved by means of various metrological tests of instruments, which are aimed at establishing the real metrological properties of a particular instrument. Based on the results of these tests, adjustment of the measuring instruments can be applied.
A lot of methods have been devoted to improve the metrological quality of measuring instruments. Within the framework of this paper, it is important to determine quality enhancing ways of instruments while operating. Effective way to improve the quality of operation is to increase the calibration frequency of measuring instruments with more accurate means of measurement or calibrator aiming the determining and excluding the systematic error. Analysis of the calibration effect on the metrological reliability of instruments carried out previously represents the most effective of the mentioned methods. One of them seems to be the built-in calibration element for each measurement cycle. It may be recommended the periodic control by an external measure.
Development methods and algorithms for instant control of metrological characteristics of measuring instruments are proposed. Methods are important to reduce the degradation of measuring instruments in industry. Also, they are aimed at enhancement of measurements exactness.
Article assesses the conditions for effective applying the instant control methods of uncertainties. The expediency of such methods, as the method of verification of the common signal source; the method of mutual recognition; method of verification using high-stable measuring instrument; method of verification with a calibrator, is considered. The last one is the most effective method efficiency of which is proven by current research.
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