Significance of measurement uncertainty on digital multi-meters
Gamya .K, Krishna. P, Lavanya .M, Venkateswarlu. M
This paper presents the calibration results with uncertainties of three digital multi-meters namely A, B & C that are used in various localized conditions to understand the calibration performance of the meters in both in ac and dc potentials. The uncertainty (Ue) values are calculated for both ac and dc potentials at defined tolerance at set points 3.8, 38 & 380V respectively. The variations in the Ue values are found to be 0.007 to 0.108V, 0.010 to 0.193Vand 0.007 to 0.374V for the ac potentials. Further, the Ue values are also measured in the dc voltages are 0.0007 to 0.0151V, 0.0007 to 0.0156V and 0.0007 to 0.0189V respectively. The calibration performance of the meters A, B & C are found to be in the order of A>B>C. The significance of uncertainty values are correlated by accounting the calibration history, usage pattern and the localized conditions.