Precision, Performance, Confidence. ™

Measurement Uncertainty in COMPASS for Flow, Test Macro

This test macro calculates measurement uncertainty for each setpoint in the test. Calculation is done per the Fluke Calibration Application Note "Implementing ISO 17025 Measurement Uncertainty Requirements In Software" dated March 2012, document 1282496C.  A link to download a copy is at the end of this Article. The macro also calculates a guardbanded tolerance and calculates TUR. Note that if you have some understanding of VBscript and macros in COMPASS for Flow then you can edit the calculations and/or add to them.

Make sure UserDefined1, UserDefined2, UserDefined3, StringData1 and StringData2 are saved to the data file in [Tools], <Options>, <Data In File>. You will need to be running an Advanced test to use this macro and this macro needs to be chosen as the "Test Event Macro" on the Data tab, and "Timed Macro Interval(ms)" needs to be 0 (zero).

It is recommended to manually verify the calculated values before relying solely on this macro.

Below is a link to a file containing the text of the macro that can be copy/pasted into the COMPASS Macro Editor as a new Test macro. Use CTRL+V to paste into the macro editor because right-clicking then paste is not an option.

Other attached files are a sample data file and calibration report generated with this macro and the attached COMPASS Report Editor template.

Rev 3, 28-August-2015 added multiple DUT capability & TUR
Rev 4, 02-Sept-2015 added units to UserDefined 1 to 3
Rev 5, 23-Sept-2015 Changed 330 in "If cCompass.CurrentTestStep = 330" to 325 because Uncertainty Parameters were not updating in data grid
Rev 6, 07-Mar-2016 Added more comments in debug statements for more info on what S1, S2,... are. Set TUR resolution to 1 digit
Rev 7, 08-Mar-2016 Added resolution for Unc. and GB Tol. in the first few lines of code. Added CInt(iC) for multiple Pressure Cycle support (PresCyclIndex)
'Rev 8, 05-Apr-2016 Changed to UserDefined 8 to 10 and StringData9 and 10
'Moved "Tolerance with Guardband failed" message box to the correct if-then-else statement

Contact Fluke Calibration Flow Technical Support at the link below or by phone at 1.877.355.3225 with any questions.

Have more questions? Submit a request


Please sign in to leave a comment.