Dissemination of the « Planck-Kilogram »

Metrologists all over the world are looking at the activities of the Metre Convention concerning the New International System of Units on the basis of fundamental constants. Especially the redefinition of the kilogram will have consequences in nearly all fields of physics, engineering and trade. A new definition of a base unit imperatively implies thoughts about the future dissemination of the unit. After a short glance at the potential of the Kibble(Watt)-Balance the presentation will describe the strategy of the Physikalisch-Technische Bundesanstalt to use silicon spheres of different qualities for the dissemination of the quantum based kilogram to the macroscopic world. Beside metrological aims the availability of realisations is of crucial importance within a future dissemination chain. Aspects like the connection to the established system as an important aspect for acceptance, the applicability of the developed tools and procedures for using such spheres as mass standards or the current state of activities to proof the expected excellent long term characteristics of silicon spheres in use will be presented

The Planck-Balance – a self-calibrating precision balance for industrial applications

A self-calibrating balance is proposed, which allows the calibration of weights in a continuous range from 1 mg to 1 kg. This so-called Planck-Balance (PB) is similar to the physical approach of Kibble Balances that allow the mass to be derived from the Planck constant. Using the Planck-Balance no calibrated mass standards are required during weighing processes any longer, because all measurements are traceable to the electrical quantities and the Planck constant. This allows a new approach of balance types after the expected redefinition of the SI-units by end of 2018. In contrast to many scientific oriented developments, the PB is focused on industrial use. Therefore, two balances will be developed, a PB2 and a PB1, which will allow a relative measurement uncertainty (k = 2) of 5.3 x 10-7 and 1.7 x 10-7, respectively. Those aimed accuracies refer to the class E2 and E1 weights, as specified in OIML R 111-1. The balances will be developed in a cooperation of the PTB and TU Ilmenau in a project funded by the German Federal Ministry of Education and Research. The project started in January 2017 and will run for 3 years