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At the Swiss Federal Office of Metrology and Accreditation (METAS), the watt balance apparatus has undergone important changes in the magnetic circuit. A new magnet design has been carefully studied, experimentally tested and successfully integrated in the existing set-up. The details of this development as well as new alignment capabilities are described.

A new generation of digital multimeters was used to compare the ratios of the resistances of wire-wound reference resistors and quantized Hall resistances. The accuracies are better than 0.1 ppm for ratios as large as 4: 1 if the multimeters a~ calibrated with a Josephson array.

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