Fluke Digital Multimeter - Page 25

©Fluke Calibration 2011 Basics Of Measurement Uncertainty for DMM Calibration 25
• To quantify uncertainty, the various sources of uncertainty need
to be quantified, evaluated, & combined
• Calculate a combined estimate of all the individual A and B types
of uncertainties
• This combined uncertainty is:
− a basic estimate (representing one statistical standard deviation)
− usually the RSS of all individual uncertainties
(Combining uncertainties using such an RSS technique applies to
uncertainties with standard relationships and are independent)
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Combining all the uncertainties
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