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Design of a Table-Top Watt Balance



Stephan Schlamminger, Jon R. Pratt, David B. Newell, Frank C. Seifert, Michael Liu, Leon S. Chao, Luis Manuel Pea Prez, Shisong Li, Darine El Haddad


Measurements of the Planck constant with watt balances using 1 kg masses have achieved relative standard uncertainties below 2 x 10-8. Having established a metrological link between the kilogram and this fundamental constant of nature, a redefinition of the International System of units (SI) is planned and likely to occur in 2018. In the revised SI, watt balances can be used to realize the unit of mass at any value, not just at the cardinal point of 1 kilogram. In this article, we discuss two models of table top watt balances that we have recently built at the National Institute of Standards and Technology. The capacity of these table top watt balance is 10 g and we aim for a relative standard uncertainty of 1 part per million.
Proceedings Title
NCLSI Workshop and Symposium
Conference Dates
July 24-28, 2016
Conference Location
St. Paul, MN


watt balance, news SI


Schlamminger, S. , Pratt, J. , Newell, D. , Seifert, F. , Liu, M. , Chao, L. , , L. , Li, S. and El, D. (2016), Design of a Table-Top Watt Balance, NCLSI Workshop and Symposium, St. Paul, MN, [online], (Accessed June 23, 2024)


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Created July 26, 2016, Updated November 29, 2019