Control Chart Setup
Explanation
This activity is used to set up statistical process control (SPC) for a
specific data point in a specific control
plan.
During the setup, a control chart type is chosen. There exists
several control chart types.
- p Chart - Gives information about the proportion of nonconforming units.
- np Chart - Gives information about the number of nonconforming units.
- c Chart - Gives information about the number of nonconformities.
- u Chart - Gives information about the number of nonconformities per unit.
- Xbar and R Chart - Gives information about the average and the range
of the result set of each analysis selected in the graph.
- Xbar and S Chart - Gives information about the average and the standard
deviation of the result set of each analysis selected in the graph.
- X and MR Chart - Gives information about individual
results and moving ranges for each analysis selected in the graph.
The available control chart types that can be chosen is depending on the
data type and the inpection type the specific data point has.
- If the data type is Attribute and the inspection
type is Percent the available chart types are p
Chart and u Chart.
- If the data type is Attribute and the inspection
type is Quantity the available chart types are
np Chart, c Chart, p Chart
and u Chart.
- If the data type is Variable and the inspection
type is Percent the available chart type is X
and MR Chart.
- If the data type is Variable and the inspection
type is Quantity the available chart types are
XBar and R Chart, XBar and S Chart and
X and MR Chart.
- If the data type is Categorical and the inspection
type is Percent or Quantity the
available chart type is p Chart.
It is possible to decide if any tolerance limits should be displayed in
the chart and how to calculate control limits. It is also possible to decide
whether any alarm rules should be activated for the chart.
To set up SPC for a data point click Setup SPC Data on
the Control Plan Lines tab and enter the settings
in the Variable SPC Setup dialog. To see the
default settings of the SPC setup, click
Default Settings. To
activate the control chart setup click Save Settings.
Prerequisites
- A control plan with at least one line must exist.
- SPC is enabled for the line.
System Effects
As a result of this activity, the control chart type is determined for a
specific data point in a specific control
plan. Decisions are also made about how to calculate control limits, whether to include tolerance limits in the control chart,
and whether one or many alarm rules should be activated.