Comparison of the Josephson Voltage Standards of the MSL and the BIPM (part of the ongoing BIPM key comparison BIPM.EM-K10.b)

A comparison of the 10 V Josephson array voltage standard of the Bureau International des Poids et Mesures (BIPM) was made with that of the Measurement Standards Laboratory (MSL), New Zealand, in April 2011. For this exercise, option B of the BIPM. EM- K10. b comparison protocol was applied. This option required the BIPM to provide a reference voltage for measurement by the MSL using its Josephson standard with its own measuring device. The BIPM array is kept floating from ground. The final results are in very good agreement within the combined relative standard uncertainty of 4.0 parts in 1010 for the nominal voltage of 10 V.