A critically important segment of the electrical industry is the supply of electricity using high-voltage technologies. The metrological reliability of voltage, current and electrical energy measuring devices is confirmed by timely verification of compliance of measurement errors with the requirements of standards. In export-import operations with electricity, recognition of measurement and testing results at the international level comes to the fore. Metrological traceability and measurement uncertainty assessment, which are established during the calibration of standards and measuring instruments, are important components in the recognition of measurement results. The article presents the ranges of AC voltage and current measurement values, the ranges of the corresponding measurement uncertainty and the standards used, linked in the schemes of metrological traceability chains. The construction and clarification of metrological traceability chains for high AC voltage and current measurement using instrument transformers is a relevant task that is solved in the work. The proposed chains of metrological traceability hierarchy are used in Ukraine, in particular in the State Enterprise “Ukrmetrteststandard”, which is the holder of national standards of the highest accuracy. Among others, they ensure the uniformity of measurements through the calibration of secondary and working standards, as well as the verification or calibration of working instruments for measuring high alternating voltage and high alternating current by reducing the measured value to the measurement range of electricity meters. The specified chains can be used by accredited measuring laboratories that calibrate working measuring instruments for scaling high AC voltage and current, i.e., voltage transformers and current transformers, in accordance with their own scope of accreditation.
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