Changing Control Chart Rules in QI Macros
Control Chart Rules for determining unstable points and conditions vary among the experts. QI Macros lets you select from among industry standards including Montgomery, Nelson-Juran, Westgard, AIAG, Western Electric and rules used in Healthcare. You can also create custom rules.
QI Macros default rules are the Montgomery rules from Introduction to Statistical Process Control, 4th edition pp 172-175, Montgomery.
- Click on the QI Macros menu, Control Charts and then Control Chart Rules.
- Select the control chart rules you want to use. Depending on how fast your version of Excel is, you should see QI Macros updating the rules file.
- Now just run a chart and the new rules will be applied.
- To check which rules are active, click on QI Macros, Control Charts, Control Chart Rules and then Show Current Rules. The active rules will be shown in the column labeled "n(points)." In the example below, you can tell that Juran's rules are active because the values in the "n (points)" column are equal to Juran's rules.
- Any changes made to the rules are "permanently" made. The rules will not reset if you close and reopen Excel or shut down and start up your computer.
- To reset the rules to the defaults or to another set of rules simply click on the Control Chart Rules menu and select a new set of rules or Montgomery's rules to go back to the default.
You can set your own custom stability rules using QI Macros as follows:
- Open Excel
- Open the Control Chart Rules file in each of these locations:
My Documents\QI Macros Test Data\ControlChartRules.xls
If there isn't one in that location, use:
If there isn't one in either of those two locations, use:
c:\Program Files\Microsoft Office\Office14\xlstart\QITemplates\ControlChartRules.xls
- The file will open but it will be hidden in Excel. To unhide the file in Excel 2010-2019 and Office 365, select View then Unhide.
- The control chart rules file will allow you to turn a stability test off by changing the value in the Apply rule column from True to False. Just click on a cell and change the value using the pull down arrow.
- You can also change the number of points required for each test by changing values in the n(points) column. Just select the cell and select one of the options using the pull down arrow.
- After you make your changes, save the Control Charts Rules file, re-hide it and then close and re-open Excel. Note: the changes will not take effect until you close and re-open Excel.
- To change back to the defaults, from the QI Macros menu, simply select Control Charts, Control Chart Rules, Montgomery (Default Rules). Note:There is no need to close and re-open Excel when making changes via the menu.
- Control Menu Options for Stability Analysis
- Control Chart Limit Calculations
- Show/Don't Show 1 & 2 Sigma Lines