Introduction

New to WinSPC version 8.2 is an enhanced feature called the Data Point Viewer, located on the Chart tab within the Variable Analyzer. Previously a compact version of this window was only accessible in charts withing Data Collection, Plant Monitor, and the Legacy Query Tool.  The Data Point Viewer provides details about individual subgroups and functions fundamentally the same as it previously did in Data Collection, but with a few upgrades which are highlighted in this section.  

How to use Data Point Viewer

To open the Data Point Viewer, use the following steps:

1. Log in to WinSPC as the Admin user or a user that has Administration permissions to the Variable Analyzer.
2. In the Administrator window, expand the Parts/Processes node in the Tree pane, and locate the Variable to be annotated.
3. Right-Click on the variable and select Query, to open the Variable Analyzer window.
4. Left-Click on the Chart tab to view the chart.
5. Left-Click on a subgroup to open the Data Point Viewer.

NOTE: To access the Data Point Viewer, the variable must be in its Default Subgrouping State. A Default Subgrouping State button has been added to Variable Analyzer. This button automatically returns a variable’s data to its default subgrouping state. When the Default Subgrouping button is depressed, and therefore activated, the variable is in its default subgrouping state. Whenever a change is made which has the potential to cause a variable’s data to leave its default subgrouping state, the button is deactivated, and that button will appear unpushed.

The Data tab contains detailed information about the subgroup. It consists of the following elements, labeled in the figure below:

(a)   The subgroup’s Chart Point, which is its relative number within the current subgroup range. This is a new subgroup identifier in Version 8.2 which clarifies the subgroup’s position within a subgroup range while retaining the original subgroup number (b) assigned when it was recorded in Data Collection mode.

(b)   The subgroup’s number, as assigned when the subgroup was originally collected.

(c)   The Statistics drop-down list which contains two options for the set of limits displayed: 

i. Current – with this option selected, the limits displayed in the Data Point Viewer are based on the current settings in the Calculation Settings in the Variable Analyzer panel.

ii. Historical – with this option selected, the limits displayed in the Data Point Viewer are those which were in place when the subgroup was collected. 

(d)   The subgroup’s value(s) for the chart’s defining statistics.

(e)   The subgroup’s control limits and center line for the chart’s defining statistics: UCL for upper control limit, CL for center line, and LCL for lower control limit.

(f)   The subgroup’s four warning limits for the chart’s defining statistics: UAB for the 2-s warning limit, UBC for the 1-s warning limit, LBC for the -1-s warning limit, and LAB for the -2-s warning limit. The name of each warning limit is derived from its location above or below the chart’s center line (U for upper and L for lower), followed by which two standard deviation zones it divides (either AB or BC), shown in the figure below.

(g) Information about the subgroup’s readings, including reading values, the date and time readings were collected, the user who collected them, and the computer station on which the readings were collected. A subgroup’s reading values can be edited by users who have the Edit Data option granted in their permission settings. Editing reading values causes the subgroup to be labeled with an Edit marker in the Variable Analyzer’s chart and in other areas of WinSPC. NOTE: Control tests will not be re-applied to subgroups with newly modified readings.

(h)   A list of any tags associated with the subgroup and their corresponding tag values, which can be edited with the Edit Tags button (l).

(i)   A list of any subgroup violations.

(j)   List of any assignable causes, corrective actions, or notes assigned to the subgroup, all of which can be edited or added. Adding assignable causes, corrective actions, or notes to a subgroup causes it to be labeled with a Notes marker in the Variable Analyzer’s chart and in other areas of WinSPC.

(k)   Check-box for excluding the subgroup from statistical calculations.  When checked will exclude the subgroup data from being used in the statistical calculation, also it disables the Statistics drop-down box and setting it to default to Historical.

(l)   Clicking on the Edit Tags button allow the editing of the subgroup’s tag information. Editing tag values for a subgroup causes it to be labeled with an Edit marker in the Variable Analyzer and Data Set Builder charts and a Historical marker in Data Collection mode.

The Events tab details events related to the data point, assuming that the Enable system audit trail checkbox is checked in System Settings. An event is an action initiated by a user or by WinSPC, such as the addition of an assignable cause or the change to a reading’s value. Events are stored in the WinSPC database.