Retrieving Last-Run Statistics for Variables

You can use the Plant Applications Add-in to gather statistics for multiple variables from the last product run that used the variable. You can filter on a specific product, if you wish.

Before you search for run data for variables, you’ll need to have a worksheet with Variable IDs to use as input. For more information, please see Searching for Variables.

What Statistics Are Available?

You can select one or more of the following run statistics:

Run Statistic

Definition

Run Start Time

When the run starts.

Run End Time

When the run ends.

Product Code

An abbreviated description to identify a product.

Example

A brewery's product management lists 55 Brew Unit as a product family.

The 55 Brew Unit product family lists a product identified as 55 Dark Ale (55 Dark).

Where

  • 55 Dark Ale is the product description

  • (55 Dark) is the product code.

Average

String

Value that is in the RSum table, based on the raw count of the most commonly occurring value.

 

Float

Average value for the run.

 

Integer

Average value for the run.

Standard Deviation

Standard deviation of the critical value (e.g. weight, length) within the last run.

% In Warning

Percent of time the values for the variable were inside the warning limits during the time of the run, meaning above Lower Warning and below Upper Warning.

Conformance Index

Calculated value that combines conformance to target and variation.

The data quality reject features for variables and units can also be applied to the data used in the calculations. The variable reject and unit reject features apply to this data as well as to run summaries.

Cpk

Process Capability Index analyzes how closely the last run was on target and how consistent it was around its average performance.

The Cpk targets performance between the Upper and Lower reject limits.

Note: The further apart the reject limits are, the less likely that any item will be outside those limits.

Possible results in the last run include:

 

Result

Cpk

Cp

 

  • The last run performed with minimum variation; however the item values were close to the Upper or Lower reject limits.

Low

High

 

  • Item values were on average exactly on target, but the variation in performance is high (but still lower than the tolerance band, i.e. specification interval).

Low

High

 

  • Item values are meeting the target consistently with minimum variation.

High

High

Minimum

Minimum value within the last run.

Maximum

Maximum value within the last run.

Number of Samples

Number of data points within the last run.

How?