by Dilip Shah
Most of this article was originally published in measure to measure http://asq.org/quality-progress/2016/09/measure-for-measure/resolution-resolve.html.
The invisible digit
Without an invisible digit
References and notes
- Joint Committee for Guides on Metrology (JCGM), Evaluation of Measurement Data—Guide to the Expression of Uncertainty in Measurement, first edition, section F.2.2.1, "The Resolution of a Digital Indication," 2008, http://tinyurl.com/evaluationofmeasurement.
- For more information on assessing other display-resolution scenarios, read Philip Stein’s "Measure for Measure: All You Ever Wanted to Know About Resolution," Quality Progress, July 2001, pp. 141-142.
- For additional guidance on interpolation, read Philip Stein’s "Measure for Measure: Careful Interpolation Yields Useful Information," Quality Progress, January 2000, p. 67.
- Dilip Shah, "Measure for Measure: Best of Both Worlds," Quality Progress, July 2011, pp. 54-56.
- Dilip Shah, "Measure for Measure: Keep Your Resolution," Quality Progress, March 2011, pp. 56-58.
- JCGM, International Vocabulary of Metrology—Basic and General Concepts and Associated Terms (VIM), third edition, 2012,http://tinyurl.com/vimterms.
Additional information and exception to this article are found in ASTM E74-13a provided by Henry Zumbrun in an attempt to agitate the great Mr. Shah
CMC = Calibration and Measurement Capability. This should be found on the calibration report. More information on what CMC is can be found at on our blog here http://blog.mhforce.com/2015/11/measurement-uncertainty-calibration-and.html
Res = This is the resolution of the Unit Under Test (UUT) The divisor for resolution will either be 3.464 or 1.732. - From Dilip's article you should now know what divisor to use.
Rep = Repeatability of the Unit Under Test (UUT)
Expanded Uncertainty - Typically 2 times the standard uncertainty. The appropriate k value should be used to ensure a coverage probability of 95 %.
This will all be explained in our next blog on Measurement Risk.
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