Description and metrological characteristics are presented of upgraded in 2021 equipment of National primary state standard of temperature on the temperature range from 0.3 K to 273.16 K GET 35-2021. GET 35-2021 allow to to the reproduce and disseminate the unit of temperature according to its definition accepted on 26th CGPM in 2018. Three installations of acoustic gas thermometry developed in 2012–2019 have been introduced in the National primary state standard covering ranges 79–273.16 K, 4.2–80 K, 268.16–273.16 K. The equipment for reproduction of fixed points of of International Temperature scale ITS-90 has been upgraded for uncertainty reduction. Uncertainty of reproduction of thermodynamic temperature and temperature according to ITS-90 have been calculated on the basis of investigations of upgraded equipment.
Corrigendum: Measurement of thermodynamic temperature between 5 K and 24.5 K with Single-Pressure Refractive-Index Gas Thermometry (2020 Metrologia
57 065006)
