PNNL

Abstract

Abstract—There is a relationship between the user of the result of a measurement and the act of measurement that should guide the act: the user has some specific need for the meaning contained in the result. The extent to which that need is met is a measure of the quality of the measurement. The usual metric is an uncertainty statement. This paper shows that, because of significant signal distortion, the uncertainty statement may be inappropriate outside the calibration laboratory. We propose a way to improve the situation. Better measurements are not necessarily ones with faster response or greater precision: the important point is that they meet the needs of the user. They are “fit for purpose.” The solution proposed here affects both the instrument designer and the user. It requires that additional information regarding uncertainty accompany all result values (not just those done in the calibration laboratory), and it requires changes to the way the results are handled by the user. The paper concentrates on the electric power system, but it is hoped that the ideas can be applied more broadly to field measurements.