Issue with MasterProbe qualification

[[An...]]

We have seen this several times in the past and still don't understand it. Masterprobe qualifies way out of sigma's limit value but still has a green check mark and allows the operator to continue qualification and running parts. Seems like the only indication something isnt right is the red box.

Does anyone know why the set limit value is being ignored?

Red Box Sigma.JPG

[[Ri...]]

What I see.
Your limit value is in inch mode.
Your MasterProbe qualification is in Metric mode.
A 0.0005 (Inch) set limit is 0.01257 (Metric).
Your qualification would be acceptable.

[[An...]]

Qualification program is in Metric, all of the qualification data is in metric.
I don't see any indication that it would be 0.0005" and not 0.0005mm. Calypso shouldn't let that happen even if it was possible.

I hadn't considered that possibility tho, If you have somewhere in Calypso to look for evidence that the sigma is in inches I will look into that

[[Mi...]]

Before pulling your hair out too much. I see you're using a quite new version of the software.

Make sure you have the latest service pack for your version. This type of buggy issue is what gets fixed with service packs.

[[An...]]

I will look into that when the machine is free but we have seen earlier this year at least once

[[Da...]]

It is my understanding that if the program is in metric it will qualify as metric, if it is standard then the qualification will be in standard. I have programs for both and this has held true for mine.

[[Ri...]]

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The radius value in the left image is 0.100, the radius value in the right image is 2.5001.
The value 2.5 translates to 0.0984.
The value .100 translates to 2.54.
It appears to be in both metric and inch.

[[Je...]]

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Incorrect. The values posted for the limits are deviations from previous qualification. They are not absolute values. To that note, I typically do not advise setting a limit to the X/Y/Z/Temp/Rad values for a qualification as it only references the last qualification. If you want an absolute location you should be using a qualification characteristic in a program and utilize a Result Element to determine Nominal±Tolerance. The Sigma value is absolute and not referencing the previous qualification.

Expert tip: I advise the use of a qualification program for all styli rather than utilization of the limit values settings. The limit values will not present a report with traceable results and can easily be disabled. A properly configured qualification program can be as simple or robust as you prefer it to be.

https://portal.zeiss.com/knowledge-base ... id=1796262
https://portal.zeiss.com/knowledge-base ... &id=443334

[[An...]]

My qualification program is actually how this got caught, it just wasn't caught until after the report was generated after running the whole program. First part of the program is to touch off on the reference sphere with the masterprobe then run the program. A less experienced operator saw the green check mark and thought it was good to go. Shouldn't there be a red X instead of a green check mark if the masterprobe sigma is outside of the set limit value?

[[Je...]]

Yes

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The limit values are simply a thresh-hold for the Stylus Check prompt. It does not invalidate a qualification. This would take a PCM command in order to influence the qualification status of a stylus. Unfortunately, even this would not be sufficient here as your MasterProbe should not be used for any measurement other than REF Sphere and locating stylus holders. Since it is not used in any inspection plan, it would not prompt any error unless you have a specific Result Element and/or PCM command to force a query of its reported sigma value and if that sigma value exceeds your specified setting.

The use of this setting is significantly more useful and intuitive on standard measuring styli but the MasterProbe is a unique case.

Where to set the Global limits:
Can be accessed here as well:
The "CHECK" should be set up to stop the CNC run when an inspection plan is executed:
1 - Will Cancel the run outright and report that a stylus failed the check
2 - Will give the operator the option to proceed regardless of the warning. This is possible because the qualification is still valid. It only exceeds the limit value you have established to flag a warning.

[[Mi...]]

oooo PCM to check the sigma of the MasterProbe I hadn't ever thought of that.

if (getProbe().confName <> "MasterProbe") and (getProbe("1","MasterProbe").stdProbeDev >= 0.0003) then
 	message("S Value of MasterProbe too high to continue calibrating, Please redo the MasterPobe to complete the calibration")
	cncBreak()
endif

Placed in the Presettings of a Calibration program that shouldn't allow any of the Calibration characteristics to run after the MasterProbe was done manually. Or being really mean placing it in an external .txt file to force the check prior to ANY program running...

No idea how that would actually work in reality, I wrote that code on here... and it would be fairly easy to circumvent if somebody wanted to ... but I'm sure going to test this.

[[An...]]

We do not unfortunately do not have PCM but I will try to find a way to stop the program or have an alert pop up. It is unornate Calypso allows it to continue with the MasterProbe but not with the regular Styli

[[Ri...]]

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I did not realize they were before and after.

[[Wo...]]

I haven't used an RDS in a while, but regardless of the set limit - isn't Sigma of 0.0033mm on Masterprobe way too high?
I've just had a tech replace the air bearings on XTR because the Sigma was around 0.0007mm.