Uncertainty Analysis of the Two-Output RTD Circuits on the Example of Difference and Average Temperature Measurements

• Zygmunt L. Warsza
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 934)

Abstract

This paper focuses on the expression and the evaluation of results in the case of indirect multi-parameter measurements. A theoretical basis for determining the estimates of values, the uncertainties and the correlation coefficients of indirectly obtained multi-measurand, which are processed from data of the simultaneously measured variables, is shortly presented. It is considered on the examples of a difference and an average of two-temperature indirect measurement by using the RTD circuits, which are used in the laboratory and industrial temperature control systems. The accuracy of measurements depends on the errors of two RTDs as well as two temperature values and the structure of signal conditioning circuits. If a measured temperature difference is small, the high relative accuracy cannot be obtained when two independent measuring circuits are used. The metrological parameters can be better when RTD sensors are into a common two-output measuring system. Therefore, some examples of measuring circuit structures with two RTDs are considered. The numerical example is presented.

Keywords

Measurement circuit Temperature difference Sensor Uncertainty Multi-measurand

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