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It is proposed that the operating time of vibrating-wire transducers be extended beyond their guaranteed mean-time to failure (in the absence of apparent failures) with use of the "measurement uncertainty" procedure, which is widely employed in world practice to prevent contradiction between legislated metrology and practice.Reliability is that property of an entity, which is retained over time within established limits of all parameters characterizing the capacity to perform required functions under assigned conditions of usage [1].Metrological reliability is that property wherein measurement hardware maintains established values of metrological characteristics over the course of a certain time under normal regime and operating conditions,.The term "transducer" implies a structurally isolated primary converter of a physical input quantity to an electric signal, from which these electrical signal proceed [2]. Actually, it will provide measurement information on a physical quantity.The operating principle of vibrating-wire transducers (VWT) is based on the frequency variation of natural vibrations of a resonator (wire) due to a change in its stiffness. These transducers have been widely used for some time in all branches of engineering, since they exhibit accuracy and stability. Structural characteristics of VWT and the field of their application for safety monitoring of large-scale water-development works are described in greater detail in [3].Quantitative reliability indicies of measurement hardware [4] are assigned in the form of indicators of mean operating time to failure and average service life. As applies to VWT, these indicators define primarily the limiting allowable measurement error for their entire service life. In conformity with requirements of domestic legislated metrology, these indices, in essence, normalize the time required to obtain valid measurement information on in-service VWT from inception to cessation of their service.The value of the measurement error increases monotonically during operation from the value of the base measurement error established during graduation, to attainment of the limiting error, and the onset of degradation failure. Metrological certification of VWT when placed in rotation therefore calls for assignment of a limiting measurement error, and not a base measurement error.In their catalogues, foreign suppliers of VWT similar to ours indicate only a base measurement error when the transducers are placed in rotation; here, it is important that the indicated VWT experience stable operation for an extended time, and rarely indicate the service lives of the transducers. For this reason, and at first glance, the foreign VWT have a significantly smaller error as compared with domestic transducers. As a matter of fact, this is far from the truth.For a long time now, the JSC NIIÉS has been conducting investigations of the metrological reliability of domestic VWT to create modern highly reliable vibrating-wire transducers capable of maintaining competitiveness with the better ...

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