Limits Summary and Overview

This information is specific to the latest release of PARCview:

7.2.x

Tag limits are used throughout PARCview to track when tag values violate defined thresholds or limit rules. There are three default limit types: Control, Spec, and Operator. Each limit type can have a Lower, Upper, and Target limit. Limits can be edited in several places. The first three are in PARCview: Tag Limits, Limit Calculator, and Grade Specification. The final place to edit limits is through the Excel add-in. Limits can be setup as Grade based limits, or tag specific non-grade based limits. Limit versioning is possible. Alarms can also be based off limits for each tag.

PARCSecurity Permissions

PARCsecurity Console can control access to limit configuration. Below is a summary of the rights available for Limits.

• Limit Calculation: Enables users to open the Limit Calculator within PARCview.
• Limit Configuration: Enables users to create or modify tag limits within PARCview or through the Excel Limit Editor.

These additional rights are not required but can affect your ability to calculate limits with the Excel add-in or through Grade Specification.

• Grade Maintenance: Enables users to create or modify Grades.
• Grade Specifications: Enables users to open Grade Specification.
• System Config Process Area: Grants access to the Process Area tab in System Configuration.
• System Config Process Tags: Grants access to the Process Tags tab in System Configuration.

Configuration

PARCview > Tools Tab > Tag Limits: Allows configuration of limits one tag at a time

PARCview > Tools Tab > Limit Calculator: Allows PARCview to calculate a Lower, Upper, and Target limit for you based off historical data, and then save that limit. The limit type can be Spec, Control, and Operator.

Excel > dataPARC tab > Admin Tools > Limit Editor: Allows configuration of all limits at once, by source and limit type. Limit Editor also allows for limit calculation of all limits at once, by source and limit type. Calculating limits with Excel requires the configuration of a grade on the process, adding process tags and setting up the Rollup server.

PARCview > Tools Tab> Grade Specification: Allows configuration of all tag limits tied to a specific grade.

PARCview > Tools Tab > Grades: Where Grade names can be defined, required for limit calculation in Excel.

System Configuration

The following System Configuration Tabs allow you to set defaults and configure your overall Limit settings and Limit defaults.

Limit Types tab: Where Limit types can be added, enabled, disabled, and have default colors changed. Operator limits are not visible by default.

Process tab: Where Rollup Server Averages are selected. For the Excel Limit Calculator, Day needs rolled up for non-grade based limits. For grade based limits, the Grade option needs to be rolled up. A grade tag will also need to be defined on the process. The Basis Value Tag under ‘PARCRollup Server Settings’ must be defined to roll grades up.

Process Tags Tab: Where tags can be enabled for rollup under the Calculate column, allowing for limit calculation in the Excel Limit Editor. The box in the Calculate column must be checked for each tag.

System Defaults

Limits: LimitChangeNoteRequired: True / False

Trend: TrendLimitRangeMarginPercent: On / Off

Log Files

PARCmessage is a built-in error monitoring software. It creates an ongoing log of errors generated from PARCview on the specific computer where PARCmessage is running. Errors from recent actions such as editing limits can be found in PARCmessage. It is a red or green triangle in the system tray.

Editing Limits can create log files in the PARCview install directory on the client ...\Capstone\PARCView\LogFiles.

While editing limits in Excel, errors may occur. PARCmessage will show these but you can also view errors in Excel under the dataPARC tab, via the ‘Show Errors’ button.

On the dataPARC server when the Rollup server is rolling up averages it can create log files … \Capstone\PARCRollupServer\LogFiles.

Required Server Applications

UA Server: All PARCview vr 7 functionality requires a Universal Access (UA) server.

GDS: All PARCview vr 7 functionality requires a Global Discovery Server (GDS).