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Functional Constraints and the Design of a New Watt Balance



Leon S. Chao, Stephan Schlamminger, Jon R. Pratt


The functional constraints driving the design of the new permanent-magnet driven watt balance (NIST-4) outline the variables and compromises worthy of addressing. Construction according to these design parameters will demonstrate the high precision capabilities of a large complex mass measurement system with overall uncertainties on the order of 3 parts in 108.
Proceedings Title
ASPE Annual Meeting Proceedings
Conference Dates
October 21-25, 2013
Conference Location
St. Paul, MN
Conference Title
ASPE Annual Meeting


watt balance, mass, kilogram, wheel, flexure, SI unit, redefine, magnet


Chao, L. , Schlamminger, S. and Pratt, J. (2013), Functional Constraints and the Design of a New Watt Balance, ASPE Annual Meeting Proceedings, St. Paul, MN, [online], (Accessed June 25, 2024)


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Created September 30, 2013, Updated February 19, 2017