International comparison of AC voltage ratio standards

Final Report, 7 June 2005

Euromet project No. 599 started at the beginning of June 2000 with participants from eight European countries including the Czech Metrology Institute (CMI) in Prague as pilot laboratory. The relevant quantity for the measurement of high AC voltage is the ratio of the primary and secondary voltage for an instrument transformer, which is a complex value. The errors of this ratio are given as the ratio error and phase displacement. These two quantities were subject of this international comparison.

The measurements are completed and the final report is available. This RMO Supplementary Comparison was approved by the EUROMET TCEM and is registered as EUROMET.EM-S21 in the KCDB. The final report can be downloaded from the BIPM web-site.


Measurements were performed during the years 2000 and 2001, in March and April is planned performing of a supplementary measurement in Spain.

Electricity and Magnetism (EM)
Coordinating Institute
CMI (Czech Republic)
Further Partners