Advanced PI Calculation Engine Makes Complex PI Calculations Easy! Use of EDICTvb for Multi-Plant...

Advanced PI Calculation Engine

Makes Complex PI Calculations Easy!

Use of EDICTvb for Multi-Plant Advanced PI Calculations

Dane Overfield EXELE Information Systems, Inc.Dean E. Brown Dow Corning

EDICTvb Advanced PI Calculation Engine

• Microsoft NT4.0 (x86) PI client application• Outputs to PI tags on either PI2.x or PI3.x• User defines calculation logic (including input and

output PI tags) in EDICTvb “equation dictionaries”• EDICTvb creates compiled Visual Basic 32-bit

executables with all of the necessary PI-API routines, scheduling logic and error handling.

Overview


• Microsoft NT4.0 (x86) SP3 or higher • Microsoft Visual Basic 5.0 or 6.0• PI2.x or PI3.x PI Server• TCP/IP communication to the PI Server

Note: If you have a PI3.x Intel PI Server, EDICTvb can run on the same machine.

Requirements

Sample equation dictionary


• Accepts PI Tag names directly in equation logic and automatically codes PI access routines.

• Generates uniform and easy-to-maintain documented equations

• Over 85 built-in functions for PI archive and point database access

• Support for user-defined functions and subroutines• Allows calls to external libraries (DLLs)• Calculations can include tags from multiple PI

Servers

Key features


• Includes built-in error handling OR allows user-controlled error handling

• Order-of-execution control • Outputting of values with timestamps in the past• Supports using local variables (which retain their

value between executions) • Allows advanced Visual Basic constructs (arrays,

nested ifs, loops, Select Case statement)• VB language support (intrinsic functions, ODBC,...)• Virtually no limit in the number of logic lines

Key features (cont’d)


EDICTvb Edit: Equation editor which allows the user to create and compile EDICTvb dictionaries (.DIC files)

EDICT Server: NT Service responsible for starting and stopping equation executables

EDICT Control: used to interactively configure, monitor, start and stop equations (GUI to EDICT Server)

EDICTvb Components


Equation editor which allows the user to create and compile EDICTvb dictionaries (.DIC files)

Each equation dictionary (.DIC file) created• Can contain multiple output tags• Runs on the same interval (time, event or exception)• Creates one Visual Basic executable

EDICTvb Edit


feature-rich code editor

dictionary and function wizards

language sensitive editor

PI Tag search and Point attributes dialogs

Built in dictionary compilation using the Visual Basic compiler

EDICTvb Edit includes...


What happens during a dictionary compile?

CALC.DIC Equation Dictionary created using EDICTvb Edit

CALC.BAS Visual Basic Module created from CALC.DIC. Contains all PI-API / timing code/ error handling

CALC.VBP Visual Basic Project containing

• CALC.BAS: Basic code generated from the dictionary

• EDICTdll.BAS: DLL function declarations

• EDICTfcns.BAS: any user-written Visual Basic functions

CALC.EXE Visual Basic Executable created from CALC.VBP


WindowsNT Service responsible for starting and stopping the equation dictionary executables

Can be configured to stop and restart all equation at system shutdown and startup

EDICT Server


configure, monitor, start and stop equation dictionaries

GUI interface to EDICTServer NT Service

Local or remotecontrol of equations

EDICT Control


Download a free version at..

http://www.exele.com



Why Dow Corning Chose EDICTvb

A business case for documented and accurate equations in PI.


Who Is Dow Corning?

• World Leader in the manufacture of silica products.

• Main product families are rubbers, lubricants, sealant, electronics.

• Sites around the globe.

• Customers around the globe.


What Did Our Company Need From Calculated Data?• Accuracy

• Compatibility

• Dependability

• Logical Syntax

• Simple Syntax

• Straightforward Administration

• Scalability


Accuracy

• Related to Documentation of the equation

• Trace and Call Trace capabilities

• Depends on PI which is our Corporate Standard


Compatibility

• Made to work with PI.

• Uses VBA syntax which allows Excel users to quickly create or convert equations


Dependability

• NT Platform

• An equation can be run or managed from different EDICTvb servers

• Equations can be developed Off-Line and brought into production at a later time and in a controlled environment.


Logical Syntax

• IF - Then - ElseIf - Else

• Variables and Constants

• VBA compatible

• PI Function compatibility


Usability By Normal Users

• VBA Compatibility

Example: Assign a college co-op to create equations based on spreadsheets that an engineer took weeks developing.


Straight Forward Administration

• We chose a central server model

• We use local copies of EDICTvb for the administrators to develop equations.

• If needed the local copies can be used to manage the equations.

• Equation control in Client/Server mode


Scalability• The PI System grows• The Uses of PI grows (Operators, Engineers,

Business with SAP)• Control systems grow as the demand for

specialized products increases• If the system can’t grow we are done.• Current count of equations implemented is

greater than 5000


EXELE’s Willingness to Work With Us.• Responsiveness to calls

• Creation of New supported functions

Advanced PI Calculation Engine Makes Complex PI Calculations Easy! Use of EDICTvb for Multi-Plant...

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