Tests on the IEN electrometric AC-DC transfer standard

Tests on the electrometric AC-DC transfer standard built at IEN have been performed. The instrument was shown to work correctly, and comparison with thermal converters showed a short-term repeatability (1/spl sigma/) of about 2 parts in 10/sup 6/. Mechanical effects such as deformations and vibrations have been analyzed, both theoretically and experimentally. Direct determinations of the transfer difference made using thermal converters have shown results almost comparable with those obtained by the step-up procedure. The long-term stability of the instrument has also been investigated.