As part of the ongoing BIPM key comparison BIPM.EM-K11.a and b, a comparison of the 1.018 V and 10 V voltage reference standards of the BIPM and the Bulgarian Institute of Metrology, BIM, was carried out in April 2019. The objective for BIM in participating in this comparison was to demonstrate the international equivalence of its DC voltage measurement results and to support the calibration and measurement capabilities (CMCs) published in the Key Comparison Database of the BIPM (KCDB).

Two BIPM Zener diode-based travelling standards (Fluke 732B) were shipped to Sofia in March 2019.

At the BIPM, the reference standard for DC voltage is a primary voltage standard based on the Josephson effect, developed by the BIPM. The output electromotive force (EMF) of each travelling standard was measured against the Josephson Voltage Standard (JVS) before and after the measurements at BIM. At the BIM, the reference standard is a commercial JVS.

The final result of the comparison is presented as the difference between the values assigned to DC voltage standards by BIM, at the level of 1.018 V and 10 V, at BIM, UBIM, and those assigned by the BIPM, at the BIPM, UBIM, at the reference dates of the 26^th of March 2019.

UBIM - UBIM = - 0.01 V; uc = 0.02 V, at 1.018 V

UBIM - UBIM = + 0.30 V; uc = 0.09 V, at 10 V

where uc is the combined standard uncertainty associated with the measured difference.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

作为正在进行的 BIPM 关键比较 BIPM.EM-K11.a 和 b 的一部分，2019 年 4 月对 BIPM 和保加利亚计量研究所 BIM 的 1.018 V 和 10 V 电压参考标准进行了比较。 BIM 参与此次比较的目的是展示其直流电压测量结果的国际等效性，并支持 BIPM 关键比较数据库 (KCDB) 中发布的校准和测量能力 (CMC)。

两个基于 BIPM 齐纳二极管的移动标准 (Fluke 732B) 于 2019 年 3 月运往索非亚。

在 BIPM，直流电压的参考标准是由 BIPM 开发的基于约瑟夫森效应的初级电压标准。在 BIM 测量之前和之后，根据约瑟夫森电压标准 (JVS) 测量每个移动标准的输出电动势 (EMF)。在 BIM 中，参考标准是商业 JVS。

比较的最终结果被呈现为分配给由BIM DC电压标准值之间的差，在1.018 V和10V，在BIM，水平ū BIM和由BIPM那些分配，在BIPM，û BIM，参考日期为2019 年 3 月26^日。

U BIM - U BIM = - 0.01 V；uc = 0.02 V，1.018 V

U BIM - U BIM = + 0.30 V；uc = 0.09 V，10 V

其中 uc 是与测量差异相关的组合标准不确定度。

要访问本文的正文，请单击最终报告。请注意，此文本出现在 BIPM 密钥比较数据库 https://www.bipm.org/kcdb/ 的附录 B 中。

根据 CIPM 互认安排 (CIPM MRA) 的规定，最终报告已通过同行评审并由 CCEM 批准发布。