# Trend Settings

Trend Settings screen is used to set the trends for X Bar R charts in measurement screen.

Check the box against Ppk if you wish to consider it for Trend Settings.

The trend control checks can be enabled for the mean and/or the range charts by clicking the appropriate check box. If a trend control check is enabled, the size of the trend as the number of consecutive points must be specified via the spin box next to the check boxes. Trend control checks provide a way to determine the out of control status of a sample. There are three types of control checks: Points Outside Control Limits, Trend Analysis and Zone Analysis

The Runs Up and Runs Down checks must share the same trend size as to the Runs Greater Than Mean and Runs Less Than Mean Checks.

Error Code Entry This checkbox is used to enable the display of Corrective Action screen so that the operator can take the corrective action when any trend is raised during data collection.

Points Outside Control Limits You may check this option for Mean and/or range to raise a trend if the sample just collected lies outside the control limits but within the specification limits.

Middle Third You may check this option for Mean and/or Range to raise a trend whenever more than two thirds of the mean of the sample just collected and the means/ranges of all previous samples collected are within a one sigma spread about the center line of the Mean/Range chart.

Zone A You may check this option for Mean chart, to raise a trend if consecutive 2 of 3 samples lie in Zone A+ or above/Zone A- or below. You may check this option for Range chart, to raise a trend if consecutive 2 samples lie in Zone A+ or above, or if consecutive 4 samples lie in Zone A- or below.

Zone B You may check this option for Mean chart, to raise a trend if consecutive 4 of 5 samples lie in Zone B+ or above/Zone B- or below. You may check this option for Range chart, to raise a trend if consecutive 3 samples lie in Zone B+ or above, or if consecutive 6 samples lie in Zone B- or below.

Zone C You may check this option for Mean chart, to raise a trend if consecutive 8 samples lie in Zone C+ or above/ Zone C- or below. You may check this option for Range chart, to raise a trend if consecutive 10 samples lie in Zone C- or below, or if consecutive 7 samples lie in Zone C+ or above.

Up You may check this option for Mean/Range chart to raise a trend if the mean/range is increasing for consecutive no of samples as specified in the Trend Size.

Down You may check this option for Mean/Range chart to raise a trend if the mean/range is decreasing for consecutive no of samples as specified in the Trend Size.

Greater Than You may check this option for Mean/Range chart to raise a trend if the mean/range of the current sample and all the previous consecutive no of samples as specified in the Trend Size, lie above the center line.

Less Than You may check this option for Mean/Range chart to raise a trend if the mean/range is of the current sample and all the previous consecutive no of samples as specified in the Trend Size, lie below the center line.

For Up, Down, Greater Than and Less Than options two levels viz. Level 1 and Level 2 are present.