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Data for PPM and DPMO Calculation

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#55344

Data for PPM and DPMO Calculation | 2 July, 2008

Hi,

Say I'm going to calculate my PPM and DPMO, do I have to include in my defects data an item that the root cause is already identified? example is if I have 4 components with Land Design issues (incorrect dimension) and is causing me insufficient solder and misalignment, do i still count these as defects in my PPM and DPMO Calculation?

thanks and regards,

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#55352

Data for PPM and DPMO Calculation | 3 July, 2008

I would...and then use the data of the known issues as part of the secondary analysis. The defect is a defect, one way or the other. You can use the secondary analysis of your PPM numbers to continue to drill down in the process. If your overall PPM is, say, 1000, but 500 defects are the known defect, your adjusted PPM is 500...and go after the process defects that make up the highest percentage of the remaining defects.

You can also use that data to help drive the redesign of those issues.

cheers ..rob

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