Reference standards-copies of mass unit: calibration 2020 using vacuum comparator CCL 1007

The article discusses the calibration results of reference standards-copies according to the State Primary Standard of the Mass Unit using the new CCL 1007 vacuum comparator and buoyancy artifacts. The authors provided historical data on the calibrations of copies of the International Prototype of the Kilogram (IPK) starting from 1892, including the Russian prototype № 12. The instability of the prototype of the kilogram No. 12 corresponds to international values and is assessed at 5 · 10–11 kg per year. Changes in the mass of copies are assessed in relation to the mass of the IPK, but it is impossible to determine to what extent it has changed. This was the reason for the adoption of a new value of the kilogram. Following the adoption at the 26th meeting of the General Conference on Weights and Measures (CGPM) held in Paris in November 2018, Planck constant was numerically established with absolute accuracy, and total uncer tainty of 1 · 10–8 kg was assigned to the mass of the IPK. Thus, the authors set the aim to preserve the numerical value of the total uncertainty of the reference standards-copies by reducing the transfer error of the State Primary Standard by 10 times. The article presents the calibration results of six reference standards-copies in relation to prototype No. 12 with the primary data processing using the method of least squares, and the uncertainty budget is provided. The calibration results of the reference standards-copies confirmed the accuracy increase of the transfer unit by 10 times in the range from 6 · 10–9 kg to 6 · 10–10 kg by the use of a vacuum comparator graduated 0.1 μg and buoyancy and sorption artifacts in direct measurements of air density. This has made it possible to compensate for the additional uncertainty attributed to the IPK based on the determination of the Planck constant value and to ensure the mass calibration of all accuracy grades preserving the entire hierarchical system of transferring the mass unit in the country.

Metrological Assurance of Gas Calorimeter and Wobbe Index Analyser

The paper describes research on metrological assurance of such measuring instruments as gas calorimeters and Wobbe index analysers. The purpose of the performed research is development of reference materials for gases with certified value of net volume-basis calorific value traceable to Russian state primary standard. Input set of candidate gases is hydrogen, methane, ethane and propane, as well as the target uncertainty of lower volumetric combustion energy value equal to 0,3 % – both were selected basing on results of metrological characteristics analysis of calorimetric equipment. The certified value of lower volumetric combustion energy is traceable to the State Primary Standard of combustion energy, specific combustion energy and volumetric combustion energy units GET 16. The certified value of selected gases and the uncertainty of this value were estimated with usage of comparing calorimeters for the combustion of high- and low-calorie gases «USVG» and «USNG» included in GET 16. Results obtained during investigational study and reference materials characterisation confirmed the stated accuracy. The continuance in prospect may allow development of reference materials for gas imitating mixtures of natural and casing-head gases as well as include Wobbe index in the list of certified characteristics.

Research of the State Primary Standard of the unit of scaling factor of AC voltage up to 750/√3 kV

All electrical energy is produced, transmitted and distributed at high voltages. In this case, the measurement of the amount of electricity is carried out by electricity meters together with voltage transformers (VTs). The largest capacities are transmitted and distributed on power transmission lines of voltage of class 750 kV. In Ukraine there are about two hundred measuring VTs of class 750 kV. In addition, power facilities have been actively built recently, which will also require the installation of 750 kV transformers. Working VTs of substations for a class of 750 kV may have great weight and dimensions. Their height is 7 m and weight is 4000 kg. Working measurement standards have the same weight and dimensions. Therefore, obtaining the size of a physical quantity from the measurement standards of other countries is very difficult for two reasons: it is very difficult to transport such working measurement standards abroad; only a few countries have measuring instruments with a voltage of 750 kV. The purpose of the article is to highlight the results of researches of the State Primary Standard of the unit of scaling factor of alternating current (AC) voltage up to 750/√3 kV, in particular: formation of the composition of a set of measuring instruments for the reproduction of the unit of scaling factor; establishing a method for reproducing the unit of scaling factor; estimation of uncertainty of measurements and other metrological characteristics while transferring the unit of scaling factor. The article presents the results of the research of the newly established State Primary Standard of the unit of scaling factor of AC voltage up to 750/√3 kV, which are of great practical importance. Those researches are aimed at improving the metrological traceability of AC high-voltage at the national level. Keywords: AC high-voltage; measurement standard; measurement; calibration; uncertainty of measurement.

Traceability assurance of results of measurements for pollutant substances content in industrial emissions by automatic measuring systems

The results of the development of a gas mixing and analytical stand (reference complex) for testing in order to approve the type of automatic measuring systems (AMS) for determining the content of pollutants in industrial emissions are presented. During the use of the AMS test bench, the units of molar fraction and mass concentration are transferred from the State primary standard of units of molar fraction, mass fraction and mass concentration of components in gas and gas condensate media GET 154 to the tested measuring gas channels of AMS, thereby ensuring traceability of AMS measurement results to the State primary standard GET 154.

State primary standard of optical density unit GET 206-2016

The description of the State Primary Standard of optical density unit GET 206-2016 is given. The principle of operation of the standard, based on filtering the luminous flux of transmitted and reflected light, is described. The composition of the standard and its metrological characteristics are presented. Data on the study of the geometric and spectral characteristics of the standard are presented. Currently, GET 206-2016 allows solving the problems of metrological support of optical transmittance density measuring instruments (radiographic non-destructive quality control of materials in various industries) and optical reflection density measuring instruments (printing, applications of energy-saving and graphic technologies).