Intercomparison of DC voltage ratios up to 1000 V (follow-up)

Project Description

As a follow-up of comparison EUROMET.EM-K8, a new comparison was organised for those participants willing to improve their results. Four laboratories decided to participate. The protocol is practically the same as for EUROMET.EM-K8, but with a better definition of the form for presentation of the uncertainty budget and deletion of the optional measurements at low voltage. The comparison started in September 2003 with preliminary measurements at the pilot laboratory. Then the standard was shipped to the first laboratory, CMI. The link to the CCEM-K8 key comparison reference value will be given by the pilot laboratory.

Final Report 2005-01-12

As a follow-up of comparison EUROMET.EM-K8, a new comparison named EUROMET.EM-K8.1 was organised for those participants willing to improve their results. Four laboratories decided to participate. The protocol was practically the same as for EUROMET.EM-K8, but with a better definition of the form for presentation of the uncertainty budget and deletion of the optional measurements at low voltage. The comparison started in September 2003, with preliminary measurements at the pilot laboratory. The circulation of the standard ended in February 2004. Before the Draft A report was released, in June 2004, one laboratory, namely CMI, withdrew. The Draft A report was approved by the participants in September 2004 and the resulting Draft B was then submitted to the comparison support group, which ended his review in November of the same year. The final report, which also evaluates the degrees of equivalence with respect to the key comparison reference value, is now under approval of the Working Group on Low Frequency of the CCEM and should soon appear on the Key Comparison Data Base.

The results of all three remaining participants agree with the result of the pilot laboratory within the stated expanded uncertainties.