Rockwell Automation PLC-5 User Manual

Fieldbus Solutions for Rockwell Automation’s Integrated Architecture

ProcessLogix, ControlLogix, and PLC5

User Manual

Important User Information

Because of the variety of uses for the products described in this publication, those responsible for the application and use of these products must satisfy themselves that all necessary steps have been taken to assure that each application and use meets all performance and safety requirements, including any applicable laws, regulations, codes and standards. In no event will Allen-Bradley be responsible or liable for indirect or consequential damage resulting from the use or application of these products.

Any illustrations, charts, sample programs, and layout examples shown in this publication are intended solely for purposes of example. Since there are many variables and requirements associated with any particular installation, Allen-Bradley does not assume responsibility or liability (to include intellectual property liability) for actual use based upon the examples shown in this publication.

Allen-Bradley publication SGI-1.1, Safety Guidelines for the

Application, Installation and Maintenance of Solid-State Control

(available from your local Allen-Bradley office), describes some important differences between solid-state equipment and electromechanical devices that should be taken into consideration when applying products such as those described in this publication.

Reproduction of the contents of this copyrighted publication, in whole or part, without written permission of Rockwell Automation, is prohibited.

Throughout this publication, notes may be used to make you aware of safety considerations. The following annotations and their accompanying statements help you to identify a potential hazard, avoid a potential hazard, and recognize the consequences of a potential hazard:

WARNING

Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may lead to personal injury or death, property damage, or economic loss.

ATTENTION

Identifies information about practices or circumstances that can lead to personal injury or death, property damage, or economic loss.

IMPORTANT

Identifies information that is critical for successful application and understanding of the product.

About this Document

Preface

Contents guide

Table P.A Content Summary

The following table summarizes each chapter in this document.

Read this chapter: If you need to:

Chapter 1, The Fieldbus Communication Model or network layer?

Chapter 2, Integrating Fieldbus into ProcessLogix R400.0

Chapter 3, Planning Considerations be responsible for setting up the hardware infrastructure to support fieldbus devices. This

Chapter 4, Configuration be the one configuring the control strategy through Control Builder. This section provides

Chapter 5, Operation be monitoring system operation. This section provides an overview of functions you can monitor

Chapter 6, General Maintenance, Checkout and Calibration

become familiar with the Fieldbus Foundation is or what constitutes the FOUNDATION Fieldbus® technology. This section also includes descriptions of some standard fieldbus function blocks and describes the role of Device Descriptions and block parameters for general reference.

gain some insight on what functional relationships result from the integration of fieldbus devices with a ProcessLogix system. The information in this section will be helpful background for planning and configuring your control strategy.

section identifies the things you should consider before installing any equipment and provides detailed procedures for how to install the Fieldbus Interface Module (FIM) and its companion Remote Termination Panel (RTP).

detailed procedures for including fieldbus functional components in your overall control strategy. It includes creating hardware blocks, making templates, associating blocks, assigning modules, assigning devices, and loading components

through Station displays and the Monitoring tab in Control Builder.

be responsible for maintaining and trouble shooting system operation. This section provides information about replacing components, upgrading firmware in uncommissioned devices, and checking device calibration.

Chapter 7, Using the ControlNet-to-FOUNDATION Fieldbus H1 Linking Device

Appendix A

Appendix B reference Fieldbus status display indications.

Appendix C define the mode change conditions.

Appendix D review general Fieldbus wiring considerations.

Appendix E use Fieldbus Library Manager to create device template for Control Builder

Appendix F follow a hands-on example explaining how to configure and monitor a field bus device using

1 Publication 1757-UM006A-EN-P - May 2002

use the 1788-CN2FF H1 Linking Device.

reference

the 1788-CN2FF.

the standard function block parameters.

About this document P-2

Conventions

Table P.B Convention Definitions

Term /Type Representation

Click Click left mouse button once. (Assumes cursor is positioned on

Double-click Click left mouse button twice in quick succession. (Assumes

Drag Press and hold left mouse button while dragging cursor to new

Right-click Click right mouse button once. (Assumes cursor is positioned on

<F1> Keys to be pressed are shown in angle brackets. Press <F1> to view the online Help.

<Ctrl>+<C> Keys to be pressed together are shown with a plus sign. Press <Ctrl>+<C> to close the window.

File->New Shows menu selection as menu name followed by menu

>D:\setup.exe< Data to be keyed in at prompt or in an entry field. Key in this path location

Meaning Example

object or selection.)

cursor is positioned on object or selection.)

screen location and then release the button. (Assumes cursor is positioned on object or selection to be moved.)

object or selection.)

selection

The following table summarizes the terms and type representation conventions used in this Guide.

Click the Browse button.

Double click the Station icon.

Drag the PID function block onto the Control Drawing.

Right-click the AND function block.

Click File->New to start new drawing.

>D:\setup.exe<.

Publication 1757-UM006A-EN-P - May 2002

About this document P-3

Rockwell Automation Technical Support

Rockwell Automation offers support services worldwide, with over 75 sales/support offices, 512 authorized distributors, and 260 authorized systems integrators located throughout the United States alone, plus Rockwell Automation representatives in every major country in the world.

Local Product Support

Contact your local Rockwell Automation representative for:

• sales and order support

• product technical training

• warranty support

• support service agreements

Obtain Technical Product Support

If you need to contact Rockwell Automation for technical assistance, first call your local Rockwell Automation representative, then:

If you need to contact Rockwell Automation for technical assistance, try one of the following methods:

Type of technical support: Access at:

Personalized Service Call your local Rockwell Automation representative

Pre-sales Technical Support 1.440.646.3638 (3NET)

Post-sales Technical Support 1.440.646.5800

Email your questions racleasktheexpert@ra.rockwell.com

Internet www.ab.com

Publications www.theautomationbookstore.com

Your Questions or Comments about This Manual

If you find a problem or have a comment about this manual, please notify us of it on the enclosed How Are We Doing? form (at the back of this manual).

If you have any suggestions about how we can make this manual more useful to you, please contact us at the following address:

Rockwell Automation, Allen-Bradley Company, Inc. Control and Information Group Technical Communication 1 Allen-Bradley Drive Mayfield Heights, OH 44124-6118

Publication 1757-UM006A-EN-P - May 2002

About this document P-4

Notes:

Publication 1757-UM006A-EN-P - May 2002

Important User Information . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Preface

About this Document

The Fieldbus Communication Model

Contents guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-2

Rockwell Automation Technical Support . . . . . . . . . . . . . . P-3

Local Product Support . . . . . . . . . . . . . . . . . . . . . . . . . P-3

Obtain Technical Product Support . . . . . . . . . . . . . . . . P-3

Your Questions or Comments about This Manual . . . . . P-3

Chapter 1

Fieldbus Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

About the Fieldbus Foundation. . . . . . . . . . . . . . . . . . . 1-1

Want more information? . . . . . . . . . . . . . . . . . . . . . . . . 1-1

What is Fieldbus? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Open Communications Architecture . . . . . . . . . . . . . . . 1-3

Communication Layer Description . . . . . . . . . . . . . . . . 1-4

Standard Function Blocks . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

About Modes of Operation. . . . . . . . . . . . . . . . . . . . . . 1-8

Analog Input Block . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9

Analog Output Block . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11

Bias/Gain Block. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Control Selector Block . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Discrete Input Block . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17

Discrete Output Block . . . . . . . . . . . . . . . . . . . . . . . . . 1-18

Manual Loader Block . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19

Proportional/Derivative Block . . . . . . . . . . . . . . . . . . . 1-21

Proportional/Integral/Derivative Block . . . . . . . . . . . . . 1-23

Ratio Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

Device Descriptions and Block Parameters. . . . . . . . . . . . . 1-27

About Device Descriptions . . . . . . . . . . . . . . . . . . . . . . 1-27

Device Description Language . . . . . . . . . . . . . . . . . . . . 1-27

Device Description infrastructure . . . . . . . . . . . . . . . . . 1-28

Foundation Fieldbus Performance . . . . . . . . . . . . . . . . . . . 1-29

Performance Calculation Considerations . . . . . . . . . . . . 1-29

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vi Table of Contents

Chapter 2

Integrating Fieldbus into Rockwell Automation Logix System

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Background - the goals of integration . . . . . . . . . . . . . . 2-1

Fieldbus Integrated Architecture . . . . . . . . . . . . . . . . . . 2-2

Fieldbus Interface Modules - The Key

to an Integrated System . . . . . . . . . . . . . . . . . . . . . 2-3

Configuration Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Foundation Fieldbus Configuration Tool . . . . . . . . . . . . 2-5

Centralized Operator Interface . . . . . . . . . . . . . . . . . . . 2-5

Network Management description . . . . . . . . . . . . . . . . 2-6

System Management Description . . . . . . . . . . . . . . . . . 2-6

About the Device Object . . . . . . . . . . . . . . . . . . . . . . . 2-7

About the VFD Object . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Fieldbus Device Analog Input Integration . . . . . . . . . . . 2-7

Fieldbus Analog Input data manipulation . . . . . . . . . . . 2-8

Fieldbus device Analog Output or PID integration. . . . . 2-9

Fieldbus Analog Output or PID data manipulation . . . . 2-11

Fieldbus device Discrete Input integration. . . . . . . . . . . 2-13

Fieldbus Discrete Input data manipulation . . . . . . . . . . 2-14

Fieldbus device Discrete Output data integration. . . . . . 2-15

Fieldbus Discrete Output data manipulation . . . . . . . . . 2-16

Interface Connections Summary . . . . . . . . . . . . . . . . . . 2-16

Fieldbus status data details . . . . . . . . . . . . . . . . . . . . . . 2-17

Fieldbus Status Indications . . . . . . . . . . . . . . . . . . . . . . 2-18

Control Mode Interaction. . . . . . . . . . . . . . . . . . . . . . . . . . 2-19

Fieldbus Block Modes Versus Processlogix Modes. . . . . 2-19

Control Mode Priorities and Indications . . . . . . . . . . . . 2-20

Rotary Switch Model versus Toggle Switch Model . . . . . 2-21

Display indications and mode calculation . . . . . . . . . . . 2-23

Link and Block Schedules . . . . . . . . . . . . . . . . . . . . . . . . . 2-24

Link Active Scheduler (LAS) . . . . . . . . . . . . . . . . . . . . . 2-24

Link Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-25

Function block execution schedule. . . . . . . . . . . . . . . . 2-26

Tags, Addresses, and Live List . . . . . . . . . . . . . . . . . . . . . . 2-28

Tag and address assignments . . . . . . . . . . . . . . . . . . . . 2-28

Live List and Uncommissioned Devices. . . . . . . . . . . . . 2-29

Foundation Fieldbus Performance . . . . . . . . . . . . . . . . . . . 2-30

Notification Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32

Fieldbus versus ProcessLogix Alarm Priorities . . . . . . . . 2-32

Fieldbus Alarm Conditions . . . . . . . . . . . . . . . . . . . . . . 2-33

Alert Object Formal Model . . . . . . . . . . . . . . . . . . . . . . 2-35

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Chapter 3

Table of Contents vii

1757-FIM Planning Considerations

Configurating the 1757-FIM

Reference Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Installation declaration . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

FIM and I/O module allowance . . . . . . . . . . . . . . . . . . 3-3

Fieldbus network references. . . . . . . . . . . . . . . . . . . . . 3-3

Fieldbus wiring selection and calculation . . . . . . . . . . . 3-4

Installing 1757-FIM Fieldbus Interface Module . . . . . . . . . . 3-4

Installing 1757-RTP Remote Terminator . . . . . . . . . . . . . . . 3-4

Chapter 4

Before You Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Configuring Fieldbus Components In a Control Strategy . . . 4-3

About ProcessLogix control strategy configuration. . . . . 4-3

Example Application and Control Strategy

for Procedural Reference . . . . . . . . . . . . . . . . . . . . 4-4

System Management Timers . . . . . . . . . . . . . . . . . . . . . 4-6

ACSYNCINTR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

Adding Fieldbus Interface Module to Project . . . . . . . . . 4-9

Checking link configuration . . . . . . . . . . . . . . . . . . . . . 4-12

Making a Fieldbus Device Template from

a Vendor's DD . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17

Making a fieldbus device template from

existing definition (.DEF) files. . . . . . . . . . . . . . . . . 4-22

Adding a Fieldbus Device to Project . . . . . . . . . . . . . . . 4-24

Assigning a Device to a Link in Project . . . . . . . . . . . . . 4-27

Checking Device Configuration . . . . . . . . . . . . . . . . . . 4-28

Creating Control Module for Sample PID Loop . . . . . . . 4-33

Loading Components Online . . . . . . . . . . . . . . . . . . . . . . . 4-51

About load operations . . . . . . . . . . . . . . . . . . . . . . . . . 4-51

About the new load dialog box . . . . . . . . . . . . . . . . . . 4-52

General load considerations . . . . . . . . . . . . . . . . . . . . . 4-53

Fieldbus Device States . . . . . . . . . . . . . . . . . . . . . . . . . 4-53

Fieldbus device matching rules. . . . . . . . . . . . . . . . . . . 4-54

Loading a FIM and its Links . . . . . . . . . . . . . . . . . . . . . 4-55

Loading Link contents or fieldbus device . . . . . . . . . . . 4-57

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-60

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viii Table of Contents

Chapter 5

Operating the 1757-FIM

1757-FIM General Maintenance, Checkout, and Calibration

Monitoring Fieldbus Functions Through Station Displays . . 5-1

Using Station Detail displays. . . . . . . . . . . . . . . . . . . . . 5-1

Using Station Event Summary display . . . . . . . . . . . . . . 5-2

Monitoring Fieldbus Functions Through Monitoring Tab. . . 5-2

Inactivating/Activating a Link . . . . . . . . . . . . . . . . . . . . 5-2

Monitoring/Interacting with given component/block . . . 5-4

Checking fieldbus device functional class . . . . . . . . . . . 5-5

Checking live list and interacting with

uncommissioned devices . . . . . . . . . . . . . . . . . . . . 5-6

Using the Tools Menu Functions. . . . . . . . . . . . . . . . . . 5-8

Chapter 6

Adding, Removing and Replacing Components . . . . . . . . . 6-1

About Removal and Insertion Under Power . . . . . . . . . 6-1

General Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Upgrading firmware in an uncommissioned device. . . . . . . 6-3

Interpreting Component LED Indications . . . . . . . . . . . . . . 6-5

FIM LED indications. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

Checking Fieldbus Device Calibration . . . . . . . . . . . . . . . . 6-6

Using the 1788-CN2FF, ControlNet-to-FOUNDATION Fieldbus H1 Linking Device

Chapter 7

Blocks in the Linking Device . . . . . . . . . . . . . . . . . . . . . . . 7-1

Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2

Configuration of Analog Inputs. . . . . . . . . . . . . . . . . . . 7-2

ControlNet Analog Input Objects . . . . . . . . . . . . . . . . . 7-4

Alarm Handling for Analog Inputs . . . . . . . . . . . . . . . . 7-4

Analog Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5

Configuration of Analog Outputs . . . . . . . . . . . . . . . . . 7-6

ControlNet Analog Output Objects . . . . . . . . . . . . . . . . 7-7

Discrete Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9

Configuration of Discrete Inputs . . . . . . . . . . . . . . . . . . 7-9

ControlNet Discrete Input Objects . . . . . . . . . . . . . . . . 7-10

Alarm Handling for Discrete Inputs. . . . . . . . . . . . . . . . 7-10

Discrete Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11

Configuration of Discrete Outputs . . . . . . . . . . . . . . . . 7-12

ControlNet Discrete Output Objects . . . . . . . . . . . . . . . 7-13

Alarm Handling by the HMI. . . . . . . . . . . . . . . . . . . . . . . . 7-14

Assembly Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14

MAI Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15

MAO Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15

MDI Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16

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Table of Contents ix

MDO Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16

Viewing Object Information in the NI-FBUS

Configurator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16

Changing the Linking Device Configuration . . . . . . . . . 7-17

Trends and Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-18

Tips for Connecting to a 1756-ENET Controller. . . . . . . . . . 7-19

Appendix A

Standard Function Block Parameters

Axxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Bxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2

Cxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7

Dxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-10

Exxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-14

Fxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-14

Gxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-19

Hxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-20

Ixxx Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-22

Jxxx Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-24

Kxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-24

Lxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-24

Mxxx Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-27

Nxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-29

Oxxx Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-29

Pxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-32

Qxxx Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-33

Rxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-34

Sxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-39

Txxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-46

Uxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-48

Vxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-49

Wxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-49

Xxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-50

Yxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-50

Zxxx Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-50

Fieldbus Status Display Indications

Mode Change Conditions

Appendix B

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Appendix C

Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

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x Table of Contents

Appendix D

Fieldbus Wiring Considerations

Fieldbus Library Manager

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Fieldbus Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Power Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-2

Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-3

Signal Degradation Limitations. . . . . . . . . . . . . . . . . . . . . . D-3

Cable Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-5

Cable Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-5

Signal Distortion vs Capacitance . . . . . . . . . . . . . . . . . . . . D-6

Calculating Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . D-7

Testing the Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-7

Repeaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-7

Appendix E

About Fieldbus Library Manager . . . . . . . . . . . . . . . . . . . . E-1

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2

Menu and toolbar selections. . . . . . . . . . . . . . . . . . . . . E-2

Appendix F

1788-CN2FF Installation Example

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-1

Required Hardware for Installation Example. . . . . . . . . . . . F-2

Required Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-3

Example Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-3

Connecting the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . F-5

Install the 1788-FFCT Software. . . . . . . . . . . . . . . . . . . . . . F-6

Adding an Interface Device . . . . . . . . . . . . . . . . . . . . . . . . F-7

Finding the Interface Driver Name . . . . . . . . . . . . . . . . F-9

Assigning a Path to the 1788-CN2FF . . . . . . . . . . . . . . F-10

Port Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . F-12

Installing Device Descriptions (DDs) . . . . . . . . . . . . . . . . F-14

Starting NIFB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-17

Troubleshooting the Port Configuration . . . . . . . . . . . . . . F-18

NIFB Software Install . . . . . . . . . . . . . . . . . . . . . . . . . F-18

Start FCS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-19

Modifying Device and Function Block Names . . . . . . . F-24

Changing a Tag Name . . . . . . . . . . . . . . . . . . . . . . . . F-26

Configuring the Fieldbus Device. . . . . . . . . . . . . . . . . F-29

Download the Device Configuration. . . . . . . . . . . . . . F-31

Sending Data To the PLC-5, CLX, PLX or SLC . . . . . . . . . . F-36

Schedule Data Transmission to Controllers

with RSNetworx . . . . . . . . . . . . . . . . . . . . . . . . . . F-37

PLC-5 Data Manipulation . . . . . . . . . . . . . . . . . . . . . . F-37

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List of Figures

Table of Contents xi

PLC-5 and ControlLogix Applications . . . . . . . . . . . . . . . . F-40

ControlLogix Application. . . . . . . . . . . . . . . . . . . . . . . . . F-41

Schedule the Connection Between the

Controller and the Linking Device. . . . . . . . . . . . . F-44

View the Controller Tags . . . . . . . . . . . . . . . . . . . . . . F-44

Testing the Installation Example . . . . . . . . . . . . . . . . . . . F-46

Messages to PLC-5s and CLX to Get Data from CN2FF . . . F-47 Remote Configuration of a Fieldbus Network via

the 1788-CN2FF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-49

Troubleshooting an Application. . . . . . . . . . . . . . . . . . . . F-51

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xii Table of Contents

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The Fieldbus Communication Model

Chapter

Fieldbus Organization

About the Fieldbus Foundation

The Fieldbus Foundation is a not-for-profit corporation made up of nearly 120 leading suppliers and customers of process control and manufacturing automation products. Since its inception in 1994, it is totally dedicated to developing one standard, “open,” interoperable

field communication model known as F

OUNDATION™ Fieldbus

(1)

Want more information?

Visit the Fieldbus Foundation web site at www.fieldbus.org, or the following address, for more information:

9390 Research Blvd. Suite II-250 Austin, TX 78759-9780

What is Fieldbus?

There are many digital communication technologies being promoted as the future replacement for the venerable 4–20 mA analog standard, and most are self-described as fieldbus. With the exception of FOUNDATION fieldbus, virtually all of these technologies were developed for non-process environments such as automotive manufacturing, building automation, or discrete parts manufacturing, and later adapted to process control.

Generally, they are well suited to the applications for which they were originally developed. Some of these technologies are open, some are proprietary. Every communication technology provides a method for transmitting data between various devices and a host, and some provide communications directly between devices. The various schemes differ in how well they are optimized for moving data quickly, their suitability for real-time control, the cost of hardware implementations, their networking capability for branches, spurs and long distances, and for how power is distributed.

(1)

Sections of this publication has been provided by FOUNDATION Fieldbus.

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1-2 The Fieldbus Communication Model

Comparisons among “fieldbus technologies” typically reduces to comparisons of data rates, message length, number of devices on a segment, etc. These are all important communications issues and each technology represents a particular set of trade-offs which adapt it to its original application, and each is rooted in the technology that was available or in vogue at the time of its development.

Using a strategy exactly opposite of FOUNDATION fieldbus, these various communications technologies minimize dependence on local intelligence in deference to minimum device cost, and maximize reliance on a centralized control architecture. Measurement instruments in such structures communicate to a central computing system at the request of that central system. A proprietary control application, running on the central system processes the field data and distributes control signals to other devices back in the field. Regardless of how open the communication scheme may be, the control application is always proprietary.

The key distinctions between these technologies and FOUNDATION fieldbus are; FOUNDATION fieldbus provides an open specification for both communications and the control application. FOUNDATION fieldbus distributes control functionality across the bus, making maximum use of local intelligence to improve performance and reduce total system cost. Devices are required to be interoperable, providing the user with tools to implement a control system with products from multiple manufacturers without custom programming. With FOUNDATION fieldbus, the network is the control system.

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The Fieldbus Communication Model 1-3

Open Communications Architecture

FOUNDATION Fieldbus is an enabling technology for dynamically integrating dedicated field devices with digitally based control systems. It defines how all “smart” final control devices are to communicate with other devices in the control network. The technology is based upon the International Standards Organization's Open System Interconnection (OSI) model for layered communications.

As shown in Figure 1.1, OSI layer 1 is the Physical Layer, OSI layer 2 is the Data Link Layer, and OSI layer 7 is the application layer or the Fieldbus Message Specification. A Fieldbus Access Sublayer maps the Fieldbus Message Specification onto the Data Link Layer. Fieldbus does not use OSI layers 3 to 6, and layers 2 and 7 form the Communication Stack. Also, the OSI model does not define a User Application, but the Fieldbus Foundation does.

Figure 1.1 OSI versus Fieldbus communication model

OSI Model

Application Layer

Presentation Layer

Session Layer

Transport Layer

Network Layer

Data Link Layer

Physical Layer

Fieldbus Model

User Application

Fieldbus Message

Specification

Fieldbus Access

Sublayer

Data Link Layer

Physical Layer

User Application

Communication

Stack

Physical Layer

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1-4 The Fieldbus Communication Model

Communication Layer Description

The following table provides a summarized description of the communication layers that make up the FOUNDATION Fieldbus. The Fieldbus Foundation maintains a complete library of detailed reference specifications including a Technical Overview, and Wiring and Installation Guides.

Table 1.A Communication Layer Descriptions

Layer Functional Description Associated Terms

Physical Defines the transmission medium for fieldbus signals and the message conversion tasks

to/from the Communication Stack. Based on the Manchester Biphase-L Encoding technique, so a F device interprets a positive transition in the middle of a bit time as logical “0” and a negative transition as logical “1”. Complies with existing International Electrotechnical Commission (IEC 1158-2) and the Instrumentation, Systems, and Automation Society (ISA S50.02) physical layer standards. And, it can be used with existing 4 to 20mA wiring.

Data Link (DLL) Defines how messages are transmitted on a multi-drop network. It uses a deterministic

centralized bus scheduler called a Link Active Scheduler (LAS) to manage access to the fieldbus. It controls scheduled and unscheduled communications on the fieldbus in a publish/subscribe environment. Identifies device types as Basic Device, Link Master, or Bridge. A Link Master device type can become a Link Active Scheduler (LAS) for the network.

Fieldbus Access Sublayer (FAS)

Fieldbus Message Specification (FMS)

Defines the types of services used to pass information to the Fieldbus Message Specification layer. The types of services are defined as Virtual Communication Relationships (VCR). The VCR types are Client/Server, Report Distribution, and Publisher/Subscriber. The Client/Server type handles all operator messages. The Report Distribution type handles event notification and trend reports. The Publisher/Subscriber type handles the publishing of User Application function block data on the network.

Defines how fieldbus devices exchange User Application messages across the fieldbus using a set of standard message formats. It uses object descriptions that are stored in an object dictionary (OD) to facilitate data communication. The OD also includes descriptions for standard data types such as floating point, integer, Boolean, and bitstring. A Virtual Field Device (VFD) mirrors local device data described in the OD. A physical device may have more than one VFD. Provides these communication services to standardize the way the User Applications such as function blocks communicate over the fieldbus - Context Management, Object Dictionary, Variable Access, Event, Upload/Download, and Program Invocation. Uses a formal syntax description language called Abstract Syntax Notation 1 (ASN-1) to format FMS messages and applies special behavioral rules for certain types of objects.

OUNDATION Fieldbus (FF)

H1, 31.25 kbit/s signal rate H1 Link H1 Segment HSE, High Speed Ethernet

Compel Data (CD) message Pass Token (PT) message Time Distribution (TD) message Live List Link Active Scheduler (LAS)

Virtual Communication Relationship (VCR)

Object Dictionary (OD) Virtual Field Device (VFD) Network Management Information Base (NMIB) System Management Information Base (SMIB)

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The Fieldbus Communication Model 1-5

Table 1.A Communication Layer Descriptions

Layer Functional Description Associated Terms

User Application or Function Block Application Process (FBAP)

Defines blocks to represent different types of application functions. The three types of blocks are the Resource block, the Function block, and the Transducer block. See Figure 1.2. The Resource block is used to describe characteristics of the fieldbus device such as the device name, manufacturer, and serial number. Each fieldbus device requires one Resource block. The Function block is used to define the specific characteristics of the process control function. The Fieldbus Foundation provides a set of pre-defined function blocks. A single fieldbus device can include many Function blocks to achieve the desired control functionality. See the following section, Standard Function Blocks for more information. The Transducer block is used to interface Function blocks with local input/output devices. They read sensors and command outputs, and contain information such as calibration date and sensor type. One Transducer block is usually included for each input or output Function block. These associated objects are also defined in the User Application: Link Objects, Trend Objects, Alert Objects, and View Objects. They provide linking between internal Function block inputs and outputs, trending of Function block parameters, reporting of alarms and events, viewing of predefined block parameter sets through one of four defined views. The four defined views are View 1 - Operation Dynamic, View 2 - Operation Static, View 3 - All Dynamic, and View 4 - Other Static.

Figure 1.2 Function Block Application Process based on blocks

Fieldbus Foundation Defined Blocks

User Application

Resource

Block

Resource block Function block Transducer block Link Objects Trend Objects Alert Objects View Objects View 1 - Operation Dynamic View 2 - Operation Static View 3 - All Dynamic View 4 - Other Static

Transducer

Block

Function

Block

Communication

Stack

Physical Layer

Fieldbus

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1-6 The Fieldbus Communication Model

Standard Function Blocks

The key to fieldbus interoperability is the User Application or Function Block Application Process (FBAP) that defines standard function blocks that can reside in field devices and be interconnected as a distributed process control system. A function block is a named entity that has inputs, outputs, and parameters. It performs certain functions that operate on its inputs and produce outputs in accordance with its assigned parameters. The Fieldbus Foundation Function Blocks are similar in nature to the Function Blocks used to build control strategies in the Control Builder application in the ProcessLogix system.

The Fieldbus Foundation provides the standard Function Blocks listed below for basic control functionality. They also support additional blocks for more complex applications. Please refer to the applicable Fieldbus Foundation specification for more information about these additional blocks.

Table 1.B Function Block Specifications

Function Block Abbreviation Class

Analog Input AI Input

Analog Output AO Output

Bias/Gain BG Control

Control Selector CS Control

Discrete Input DI Input

Discrete Output DO Output

Manual Loader ML Control

Proportional/Derivative PD Control

Proportional/Integral/Deriva tive

Ratio RA Control

PID Control

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The Fieldbus Communication Model 1-7

Function blocks make it possible to build a control loop using fieldbus devices that include the appropriate Function block types. For example, a pressure transmitter that contains an Analog Input and Proportional/Integral/Derivative blocks can be used with a valve containing an Analog Output block to form a control loop, as shown in Figure 1.3.

Figure 1.3 Using Function Blocks in Fieldbus Devices to Form a Control Loop

AI Block

PID Block

Fieldbus

AO Block

Device 1

Device 2

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1-8 The Fieldbus Communication Model

About Modes of Operation

Every Function block includes a mode parameter with configured permitted modes. This structured parameter is composed of the actual mode, the target mode, the permitted mode, and the normal mode. The normal mode is the desired operating mode. The actual mode reflects the mode used during block execution. The target mode may be set and monitored through the mode parameter. The permitted mode defines the allowable target mode settings. The following table provides a summary of the available modes of operation and their effect on operation.

Table 1.C Modes of Operation

Mode Abbreviation Operation Effect

Out of Service OOS The block is not being evaluated. The output is maintained at the last value, an assigned failsafe

value -last value or configured failsafe value. Set Point is maintained at last value.

Initialization Manual

IMan The block output is being set in response to the back-calculation input parameter status. When

status is no path to the final output element, control blocks must initialize to provide for bumpless transfer, when the condition clears. The Set Point may be maintained or initialized to the Process Variable parameter value.

Local Override LO Applies to control and output blocks that support a track input parameter. Also, manufacturers may

provide a local lockout switch on the device to enable the Local Override mode. The block output is being set to track the value of the track input parameter. The algorithm must initialize to avoid a bump, when the mode switches back to the target mode. The Set Point may be maintained or initialized to the Process Variable parameter value.

Manual Man The block is not being calculated, although it may be limited. The operator directly sets it through an

interface device. The algorithm must initialize to avoid a bump, when the mode switches. The Set Point may be maintained, initialized to the Process Variable parameter value, or initialized to the Set Point value associated with the previous (retained) target mode.

Automatic Auto The block's normal algorithm uses a local Set Point value to determine the primary output. An

operator may set the value of the Set Point through an interface device.

Cascade Cas The block's normal algorithm uses a Set Point value fed through the Cascade input parameter from

another block to determine the primary output value.

Remote Cascade

Remote-Out ROut The block's output is being set by a Control Application running on an interface device through the

RCas The block's Set Point is being set by a Control Application running on an interface device through

the remote-cascade in parameter. The block's normal algorithm uses this Set Point to determine the primary output value. The block maintains a remote-cascade out parameter to support initialization of the control application, when the block mode is not remote-cascade.

remote-output in parameter. The algorithm must initialize to avoid a bump, when the mode switches. The block maintains a remote-output out parameter to support initialization of the Control Application, when the block mode is not remote-output. The Set Point may be maintained or initialized to the Process Variable parameter value.

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The Fieldbus Communication Model 1-9

Analog Input Block

Figure 1.4 Functional Schematic for Analog Input Function Block

CHANNEL

Transducer

Simulate

SIMULATE

Mode

SHED_OPT

Convert

L_TYPE

LOW_CUT

XD_SCALE

OUT_SCALE

FIELD_VAL

Filter

PV_FTIME

OUT

Output

Alarms

HI/LO

OUT

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1-10 The Fieldbus Communication Model

Table 1.D Analog Input Block Specifications

Description The AI function block takes the input data from a Transducer block and calculates an output to be fed to other fieldbus

function blocks. A functional schematic of the block is shown in Figure 1.4 for reference.

Function Notes • Supports Out of Service (OOS), Manual (Man), and Automatic (Auto) modes.

• The XD_SCALE units code must match the channel units code, or the block will remain in OOS mode after being configured.

• The OUT_SCALE is normally the same as the transducer, unless the L_TYPE is set to Indirect or Ind Sqr Root, then the OUT_SCALE determines the conversion from FIELD_VAL to the output.

• If the mode is Auto, the PV is the value the block puts in OUT.

• If the mode is Man, an operator can write a value to OUT.

• The SIMULATE parameter is for testing purposes only and always initializes in the disabled state.

Equation Options FIELD_VAL = 100 x (channel value - EU@0%) / (EU@100% - EU@0%) [XD_SCALE]

Direct: PV = channel value Indirect : PV = (FIELD_VAL / 100) x (EU@100% - EU@0%) + EU@0% [OUT_SCALE] Ind Sqr Root: PV = sqrt(FIELD_VAL / 100) x (EU@100% - EU@0%) + EU@0% [OUT_SCALE]

Parameters (see Appendix A for definitions of each parameter)

ACK_OPTION ALARM_HYS ALARM_SUM ALERT_KEY BLOCK_ALM BLOCK_ERR CHANNEL FIELD_VAL GRANT_DENY

HI_ALM HI_HI_ALM HI_HI_LIM HI_HI_PRI HI_LIM HI_PRI IO_OPTS L_TYPE LO_ALM

LO_LIM LO_LO_ALM LO_LO_LIM LO_LO_PRI LO_PRI LOW_CUT MODE_BLK OUT OUT_SCALE

PV PV_FTIME SIMULATE ST_REV STATUS_OPTS STRATEGY TAG_DESC UPDATE_EVT XD_SCALE

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CAS_IN

RCAS_IN

BKCAL_OUT

RCAS_OUT

The Fieldbus Communication Model 1-11

Analog Output Block

Figure 1.5 Functional Schematic for Analog Output Function Block

BKCAL_OUT

OUT RCAS_OUT

Transducer

CAS_IN

RCAS_IN

Setpoint

SP_RATE_DN SP_RATE_UP

SP_HI_LIM

SP_LO_LIM

Mode

SHED_OPT

Out Convert

PV_SCALE

XD_SCALE

PV Convert

XD_SCALE PV_SCALE

Output

Failsafe

FSAFE_TIME

FSAFE_VAL

Simulate

SIMULATE

READBACK

OUT

CHANNEL

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Table 1.E Analog Output Specifications

Description The Analog Output function block converts the set point (SP) value to a number that can be used by the hardware

associated with the CHANNEL selection. A functional schematic of the block is shown in Figure 1.5 for reference.

Function Notes • Can use either the Set point (SP) value after limiting or the Process Variable (PV) value for the BKCAL_OUT value.

• Supports Out of Service (OOS), Local Override (LO), Manual (Man), Automatic (Auto), Cascade (Cas), and Remote Cascade (RCas) modes.

• The conversion of Set point (SP) to percent of span is based on the PV_SCALE range.

• The conversion of the percent of span to a compatible value for the hardware is based on the XD_SCALE range.

• Use the Increase to Close Option in IO_OPTS to invert the span.

• Use the Cascade mode to transfer the output of another block to the Set point of the AO block.

• If the hardware, such as a valve positioner, supports a readback value, run this value backwards through the XD

scaling to act as the PV for this block. If this is not supported, READBACK is generated from OUT.

• In the Man mode, an operator can write a value to OUT. A manufacturer must put operational limits in the Transducer, where an operator cannot access them, to permit the Man mode. If Man mode is not permitted, it must be supported as a transition mode for exiting the OOS mode

• The SIMULATE parameter is for testing purposes only and always initializes in the disabled state.

Equation Options Temp = (SP - EU@0%) / (EU@100% - EU@0%) [PV_SCALE]

OUT = Temp x (EU@100% - EU@0%) + EU@0% [XD_SCALE] Temp = (READBACK - EU@0%) / (EU@100% - EU@0%) [XD_SCALE] PV = Temp x (EU@100% - EU@0%) + EU@0% [PV_SCALE]

Parameters (see Appendix A for definitions of each parameter)

ALERT_KEY BKCAL_OUT BLOCK_ALM BLOCK_ERR CAS_IN CHANNEL FSAFE_TIME FSAFE_VAL

GRANT_DENY IO_OPTS MODE_BLK OUT PV PV_SCALE RCAS_IN RCAS_OUT

READBACK SHED_OPT SIMULATE SP SP_HI_LIM SP_LO_LIM SP_RATE_DN SP_RATE_UP

ST_REV STATUS_OPTS STRATEGY TAG_DESC UPDATE_EVT XD_SCALE

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IN_1

BKCAL_IN

CAS_IN

RCAS_IN

TRK_IN_C

TRK_VAL

The Fieldbus Communication Model 1-13

Bias/Gain Block

Figure 1.6 Functional Schematic for Bias/Gain Function Block

BKCAL_OUT

OUT RCAS_OUT

CAS_IN

RCAS_IN

IN_1

Setpoint

SP_RATE_DN SP_RATE_UP

SP_HI_LIM

SP_LO_LIM

Mode

SHED_OPT

BKCAL_OUT

RCAS_OUT

Bias & Gain

GAIN

TRK_IN_D

TRK_VAL

BKCAL_IN

Output

OUT_HI_LIM

OUT_LO_LIM

BAL_TIME

Output Track

TRK_SCALE

OUT

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Table 1.F Bias/Gain Block Specifications

Description The Bias/Gain function block can be used for biased external feedforward control or to set several unit controllers,

such as boiler masters, from one controller output, such as a plant master. A functional schematic of the block is shown in Figure 1.6 for reference.

Function Notes • Supports Out of Service (OOS), Initialization Manual (IMan) Local Override (LO), Manual (Man), Automatic (Auto),

Cascade (Cas), and Remote Cascade (RCas) modes.

• The output supports the track algorithm.

• The Balance Ramp option is supported.

• The CONTROL_OPTS selection Act on IR determines whether initialization requests are to be passed on or acted

on locally by changing the BIAS value.

• If the Act on IR option is false, a status of Not Invited (NI) or Initialization Request (IR) at BKCAL_IN will be passed to BKCAL_OUT. The BKCAL_OUT value will be calculated from the value of BKCAL_IN adjusted for SP and GAIN, as determined by the control or process status of IN_1. When the upstream block sends an Initialization Acknowledge (IA) status, this block will send IA status, since its output will now be nearly equal to the value of BKCAL_IN.

• If the Act on IR option is true, a status of NI or IR at BKCAL_IN results in an adjustment to SP to balance OUT to the value of BKCAL_IN. The IA status can be sent as soon as IR is detected. BKCAL_OUT will not request initialization.

• The TRK_VAL input brings in an external value or uses a constant. The TRK_SCALE values convert the TRK_VAL to a percent of output span value. If the CONTROL_OPTS Track Enable selection is true and TRK_IN_D is true, the converted TRK_VAL replaces the output (OUT), when the block is in Automatic, Cascade, or Remote Cascade mode. The CONTROL_OPTS Track in Manual selection must be true for this to occur in Manual mode. If the actual mode is OOS or IMan, the track request is ignored.

• If the TRK_VAL replaces the OUT, its status becomes Locked Out with Limits set to Constant. The actual mode goes to LO. The status of RCAS_OUT goes to Not Invited (NI), if not already there.

• If the status of TRK_IN_D is Bad, its last usable value will be maintained and acted upon. If the device restarts, losing the last usable value, it will be set to false.

• If the status of TRK_VAL is Bad, the last usable value will be used. If there is no last usable value, the present value of the OUT will be used.

Equation Options In Automatic mode: OUT = (IN_1 + SP) x GAIN

If IN_1 has Non-Cascade status: BKCAL_OUT = (BKCAL_IN / GAIN) - IN_1 If IN_1 has Cascade status: BKCAL_OUT = (BKCAL_IN / GAIN) - SP

Parameters (see Appendix A for definitions of each parameter)

ALERT_KEY BAL_TIME BKCAL_IN BKCAL_OUT BLOCK_ALM BLOCK_ERR CAS_IN CONTROL_OPTS

GAIN GRANT_DENY IN_1 MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM OUT_SCALE

RCAS_IN RCAS_OUT SHED_OPT SP SP_HI_LIM SP_LO_LIM SP_RATE_DN SP_RATE_UP

ST_REV STATUS_OPTS STRATEGY TAG_DESC TRK_IN_D TRK_SCALE TRK_VAL UPDATE_EVT

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Control Selector Block

Figure 1.7 Functional Schematic for Control Selector Function Block

SEL_1

SEL_2

SEL_3

SEL_1

SEL_2

SEL_3

BKCAL_IN

Selection

SEL_TYPE

Mode

OUT

BKCAL_SEL_1

BKCAL_SEL_2

BKCAL_SEL_3

BKCAL_IN

OUT_HI_LIM

OUT_LO_LIM

Back Calc

Output

OUT

BKCAL_SEL_1

BKCAL_SEL_2

BKCAL_SEL_3

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Table 1.G Control Selector Block Specifications

Description The Control Selector function block accepts input from up to three control signals and selects one for output based on

the SEL_TYPE setting of High, Middle, or Low. A functional schematic of the block is shown in Figure 1.7 for reference.

Function Notes • All inputs must have the same scaling as OUT, since any one can be selected for OUT.

• Supports Out of Service (OOS), Initialization Manual (IMan) Local Override (LO), Manual (Man), and Automatic (Auto) modes.

• If an input has a sub-status of Do Not Select, it will not be selected.

• Three separate back calculation outputs (BKCAL_SEL_1, 2, 3) are available - one for each input (SEL_1, 2, 3).

• The status will identify those inputs that are not selected. Control signals that are not selected are limited in one

direction only as determined by the SEL_TYPE selection.

• The value of each BKCAL_SEL_1, 2, 3 output is the same as OUT. The limits of back calculation outputs corresponding to not-selected inputs will be high for a low selection, low for a high selection, or one of each for a middle selection.

• If the status of an input is Bad, it is not eligible for selection. If the status of an input is Uncertain, it is treated as Bad unless the STATUS_OPTS selection is Use Uncertain as Good.

• When all inputs are Bad, the actual mode goes to Manual. This condition will set Initiate Failsafe (IFS) in the output status, if the STATUS_OPTS setting is IFS if BAD IN.

• If SEL_TYPE selection is Middle and only two inputs are good, the higher input will be selected.

• If the status of BKCAL_IN is Not Invited (NI) or Initialization Request (IR), it is passed back on all three back

calculation outputs. This causes all initializable inputs to initialize to the BKCAL_IN value. Otherwise, if the status of BKCAL_IN is not normal, it is passed back on the BKCAL_SEL_N, where N is the number of the selected input. The back calculation outputs for not-selected inputs just have the Not Selected status with the appropriate high or low limit set.

• When the mode is Manual, no input is selected. All three back calculation outputs will have a Not Invited status and Constant limits, with a value equal to OUT.

Parameters (see Appendix A for definitions of each parameter)

ALERT_KEY BKCAL_IN BKCAL_SEL_1 BKCAL_SEL_2 BKCAL_SEL_3 BLOCK_ALM

BLOCK_ERR GRANT_DENY MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM

OUT_SCALE SEL_1 SEL_2 SEL_3 SEL_TYPE ST_REV

STATUS_OPTS STRATEGY TAG_DESC UPDATE_EVT

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Discrete Input Block

Figure 1.8 Functional Schematic for Discrete Input Function Block

Transducer

CHANNEL

Table 1.H Discrete Input Block Specifications

Description The Discrete Input function block takes the discrete input data from a selected Transducer block channel and provides

Simulate

SIMULATE_D

Mode

SHED_OPT

it as an output for other fieldbus function blocks. A functional schematic of the block is shown in Figure 1.8 for reference.

Optional

Invert

FIELD_VAL_D

Filter

PV_FTIME

OUT

PV_D

Output

Alarms

OUT_D

DISC

Function Notes • Supports Out of Service (OOS), Manual (Man), and Automatic (Auto) modes.

• The FIELD_VAL_D represents the true ON/OFF state of the value from the Transducer, using XD_STATE.

• Use the IO_OPTS Invert selection to do a Boolean NOT function between the field value and the output.

• Use the PV_FTIME to set the time that the input must be in one state before it gets passed to the PV_D.

• The PV_D is always the value that the block places in OUT_D, when the mode is Automatic.

• In Manual mode, if allowed, an operator can write a value to OUT_D.

• The SIMULATE_D parameter is for testing purposes only and always initializes in the disabled state.

Parameters (see Appendix A for definitions of each parameter)

ACK_OPTION ALARM_SUM ALERT_KEY BLOCK_ALM BLOCK_ERR CHANNEL DISC_ALM DISC_LIM

DISC_PRI FIELD_VAL_D GRANT_DENY IO_OPTS MODE_BLK OUT_D OUT_STATE PV_D

PV_FTIME SIMULATE_D ST_REV STATUS_OPTS STRATEGY TAG_DESC UPDATE_EVT XD_STATE

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CAS_IN_D

RCAS_IN_D

Discrete Output Block

Figure 1.9 Functional Schematic for Discrete Output Function Block

BKCAL_OUT_D

RCAS_OUT_D

OUT_D

RCAS_OUT_D

Transducer

CAS_IN_D

RCAS_IN_D

Setpoint

Mode

SHED_OPT

Optional

Invert

SP_D

Optional

Invert

Output

PV_D

Failsafe

FSAFE_TIME

FSAFE_VAL_D

Simulate

SIMULATE_D

READBACK_D

OUT_D

CHANNEL

Table 1.I Discrete Output Block Specifications

Description The Discrete Output function block converts the value in SP_D to something useful for the hardware linked to the

CHANNEL selection. A functional schematic of the block is shown in Figure 1.9 for reference.

Function Notes • Supports Out of Service (OOS), Local Override (LO), Manual (Man), Automatic (Auto), Cascade (Cas), and Remote

Cascade (RCas) modes.

• The Set point (SP_D) supports the full cascade sub-function.

• Use the Cascade mode to transfer the output of another block to the Set point (SP_D) of the DO block.

• Use the IO_OPTS Invert selection to do a Boolean NOT function between the field value and the output.

• Use the IO_OPTS Invert selection to do a Boolean NOT function between the SP_D and the output.

• If the hardware supports a readback value, it is used for READBACK_D, and, after accounting for the IO_OPTS

Invert selection, acts as the PV_D for this block. If this is not supported, READBACK is generated from OUT_D.

• In the Man mode, an operator can force the output, in a programmable logic controller sense. If Man mode is not permitted, it must be supported as a transition mode for exiting the OOS mode

• The SIMULATE_D parameter is for testing purposes only and always initializes in the disabled state.

Parameters (see Appendix A for definitions of each parameter)

ALERT_KEY BKCAL_OUT_D BLOCK_ALM BLOCK_ERR CAS_IN_D CHANNEL FSAFE_TIME FSAFE_VAL_D GRANT_DENY

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IO_OPTS MODE_BLK OUT_D PV_D PV_STATE RCAS_IN_D RCAS_OUT_D READBACK_D SHED_OPT

ST_REV STATUS_OPTS STRATEGY TAG_DESC UPDATE_EVT XD_STATE SIMULATE_D SP_D

The Fieldbus Communication Model 1-19

Manual Loader Block

Figure 1.10 Functional Schematic for Manual Loader Function Block

BKCAL_IN

ROUT_IN

TRK_IN_D

TRK_VAL

BKCAL_IN

OUT ROUT_OUT

Filter

PV_FTIME

Mode

SHED_OPT

Alarm

HI/LO

TRK_IN_D

TRK_VAL

ROUT_IN

Output Track

TRK_SCALE

ROUT_OUT

Output

OUT_HI_LIM

OUT_LO_LIM

OUT

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Table 1.J Manual Loader Block Specifications

Description The Manual Loader function block output is not set by the block's algorithm. Its output can be set by an operator in the

Manual mode or a program in the Remote-Out mode. A functional schematic of the block is shown in Figure 1.10 for reference.

Function Notes • Supports Out of Service (OOS), Initialization Manual (IMan), Local Override (LO), Manual (Man), and Remote-Out

(ROut) modes.

• Accepts output from an AI block as its input (IN) to get a PV filtered by PV_FTIME.

• The block's algorithm uses value and status for alarming only.

• If selected, the STATUS_OPTS of IFS if BAD IN will work.

• The BKCAL_IN value and status can force balancing of the output.

• The TRK_VAL input brings in an external value or uses a constant. The TRK_SCALE values convert the TRK_VAL to

a percent of output span value. If the CONTROL_OPTS Track Enable selection is true and TRK_IN_D is true, the converted TRK_VAL replaces the output (OUT), when the block is in Remote-Out (ROut) mode. The CONTROL_OPTS Track in Manual selection must be true for this to occur in Manual mode. If the actual mode is OOS or IMan, the track request is ignored.

• If the TRK_VAL replaces the OUT, its status becomes Locked Out with Limits set to Constant. The actual mode goes to LO. The status of ROUT_OUT goes to Not Invited (NI), if not already there.

• If the status of TRK_IN_D is Bad, its last usable value will be maintained and acted upon. If the device restarts, losing the last usable value, it will be set to false.

• If the status of TRK_VAL is Bad, the last usable value will be used. If there is no last usable value, the present value of the OUT will be used.

Parameters (see Appendix A for definitions of each parameter)

ACK_OPTION ALARM_HYS ALARM_SUM ALERT_KEY BKCAL_IN BLOCK_ALM BLOCK_ERR CONTROL_OPTS GRANT_DENY HI_ALM HI_HI_ALM HI_HI_LIM HI_HI_PRIHI_LIM HI_PRI

IN LO_ALM LO_LIM LO_LO_ALM LO_LO_LIM LO_PRI LO-LO_PRI MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM OUT_SCALE PV PV_FTIME

PV_SCALE ROUT_IN ROUT_OUT SHED_OPT ST_REV STATUS_OPTS STRATEGY TAG_DESC TRK_IN_D TRK_SCALE TRK_VAL UPDATE_EVT

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The Fieldbus Communication Model 1-21

Proportional/Derivative Block

Figure 1.11 Functional Schematic for Proportional/Derivative Function Block

BKCAL_IN

CAS_IN

RCAS_IN

ROUT_IN

TRK_IN_D

TRK_VAL

FF_VAL

BKCAL_OUT

OUT RCAS_OUT

ROUT_OUT

CAS_IN

RCAS_IN

Setpoint

SP_RATE_DN SP_RATE_UP

SP_HI_LIM

SP_LO_LIM

Filter

PV_FTIME

Mode

SHED_OPT

BKCAL_OUT

RCAS_OUT

Bypass

BYPASS

Control

GAIN

BIAS

BAL_TIME

RATE

Alarm

HI/LO

DEV

FF_VAL

Feed Forward

FF_SCALE

FF_GAIN

BKCAL_HYS

TRK_IN_D

TRK_VAL

Status

BKCAL_IN

ROUT_IN

Output Track

TRK_ SCALE

Output

OUT_HI_LIM

OUT_LO_LIM

ROUT_OUT

OUT

Table 1.K Proportional/Derivative Block

Description The Proportional/Derivative function block provides classic two-mode control function for processes that handle their

own integration. When the Process Variable deviates from the Set point, the PD function acts upon the error to move the output in a direction to correct the deviation. PD blocks support cascade applications to compensate for the difference in process time constants of a primary and secondary process measurement. A functional schematic of the block is shown in Figure 1.11 for reference

Function Notes • Supports Out of Service (OOS), Initialization Manual (IMan), Local Override (LO), Manual (Man), Automatic (Auto),

Cascade (Cas), Remote Cascade (RCas) and Remote-Out (ROut) modes.

• The input (IN) passes through a filter with a time constant (PV_FTIME). The filtered value becomes the Process Variable (PV) to be used with the Set point (SP) in the block's algorithm.

• The full cascade SP sub-function is used, with rate and absolute limits. Additional control options are available to have the SP value track the PV value, when the block's actual mode is IMan, LO, Man, or ROut. Limits do not cause SP-PV tracking.

• The tuning constant used for the Proportional term is GAIN and RATE is used for the Derivative term. Some controllers use the inverse values of Proportional Band and repeats per minutes for their tuning constants. Users can choose which tuning constants they want to display.

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Table 1.K Proportional/Derivative Block

Function Notes (cont.)

Parameters (see Appendix A for definitions of each parameter)

• A BYPASS switch function is available for operators to use, when secondary cascade controllers have a bad PV and the Bypass Enable (LSB) CONTROL_OPTS is ON. The Bypass Enable option is required, since some control schemes may become unstable when BYPASS is ON. An operator can only set the BYPASS switch, when the block is in the Man or OOS mode. While BYPASS is ON, the SP value, in percent of range, is passed directly to the target output, and the value of OUT is used for BKCAL_OUT. When block mode switches to Cascade, the upstream block is requested to initialize to the value of OUT. Upon transition to bypass OFF, the upstream block is requested to initialize to the PV value, regardless of the Use PV for BKCAL_OUT CONTROL_OPTS status.

• Use the Balance Ramp CONTROL_OPTS to maintain the BIAS value, when the block is in Manual (Man) mode. An internal value follows the actual value required to maintain balance. When block mode changes to Automatic (Auto), the internal value ramps to zero contribution in BAL_TIME seconds. If Balance Ramp option is OFF or not used, the BIAS value immediately changes to follow the changes to the input or output, when the block is in Man mode.

• Use the Act on IR CONTROL_OPTS to select whether to ignore initialization requests or act on them by changing the BIAS. If this option is ON, a status of Not Invited (NI) or Initialization Request (IR) at BKCAL_IN causes the BIAS term to be adjusted to balance OUT to the value of BKCAL_IN.

• Use the Direct Acting CONTROL_OPTS to define how a change in PV relative to the SP affects the output. When Direct Acting is ON, the output increases when the PV exceeds the SP. When Direct Acting is OFF, the output decreases when the PV exceeds the SP. Be sure this option is set correctly and never changed while in the Automatic mode, since it makes the difference between positive and negative feedback. This option setting also affects the calculation of the limit states for BKCAL_OUT.

• This block includes a Feed Forward algorithm. It accepts a value that is proportional to some disturbance in the control loop as its FF_VAL input. The FF_SCALE values convert the FF_VAL to a percent of output span value. The converted value is multiplied by the FF_GAIN and added to the target output of the block's algorithm. If the status of FF_VAL is Bad, the last usable value will be used to prevent a bump in the output. When the status returns to Good, the block adjusts its BIAS term to maintain the previous output.

• The TRK_VAL input brings in an external value or uses a constant. The TRK_SCALE values convert the TRK_VAL to a percent of output span value. If the CONTROL_OPTS Track Enable selection is true and TRK_IN_D is true, the converted TRK_VAL replaces the output (OUT), when the block is in Automatic (Auto), Cascade (Cas), Remote Cascade (RCas), or Remote-Out (ROut) mode. The CONTROL_OPTS Track in Manual selection must be true for this to occur in Manual mode. If the actual mode is OOS or IMan, the track request is ignored.

• If the TRK_VAL replaces the OUT, its status becomes Locked Out with Limits set to Constant. The actual mode goes to LO. The status of BKCAL_OUT, RCAS_OUT and ROUT_OUT goes to Not Invited (NI), if not already there.

• If the status of TRK_IN_D is Bad, its last usable value will be maintained and acted upon. If the device restarts, losing the last usable value, it will be set to false.

• If the status of TRK_VAL is Bad, the last usable value will be used. If there is no last usable value, the present value of the OUT will be used.

• Use the Obey SP limits if Cas or RCas CONTROL_OPTS to use SP value after limiting in Cas or RCas mode.

• Use the Use PV for BKCAL_OUT CONTROL_OPTS to the PV value for the BKCAL_OUT value.

ACK_OPTION ALARM_HYS ALARM_SUM ALERT_KEY BAL_TIME BIAS BKCAL_HYS BKCAL_IN BKCAL_OUT BLOCK_ALM BLOCK_ERR BYPASS CAS_IN CONTROL_OPTS DV_HI_ALM DV_HI_LIM DV_HI_PRI

DV_LO_ALM DV_LO_LIM DV_LO_PRI FF_GAIN FF_SCALE FF_VAL GAIN GRANT_DENY HI_ALM HI_HI_ALM HI_HI_LIM HI_HI_PRI HI_LIM HI_PRI IN LO_ALM LO_LIM

LO_LO_ALM LO_LO_LIM LO_LO_PRI LO_PRI MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM OUT_SCALE PV PV_FTIME PV_SCALE RATE RCAS_IN RCAS_OUT ROUT_IN ROUT_OUT

SHED_OPT SP SP_HI_LIM SP_LO_LIM SP_RATE_DN SP_RATE_UP ST_REV STATUS_OPTS STRATEGY TAG_DESC TRK_IN_D TRK_SCALE TRK_VAL UPDATE_EVT

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The Fieldbus Communication Model 1-23

Proportional/Integral/Derivative Block

Figure 1.12 Functional Schematic for Porportional/Integral/Derivative Function Block

BKCAL_IN

CAS_IN

RCAS_IN

ROUT_IN

TRK_IN_D

TRK_VAL

FF_VAL

PID

BKCAL_OUT

OUT

RCAS_OUT

ROUT_OUT

CAS_IN

RCAS_IN

Setpoint

SP_RATE_DN SP_RATE_UP

SP_HI_LIM

SP_LO_LIM

Filter

PV_FTIME

Mode

SHED_OPT

BKCAL_OUT

RCAS_OUT

Bypass

BYPASS

Control

GAIN

RESET

BAL_TIME

RATE

Alarm

HI/LO

DEV

FF_VAL

Feed Forward

FF_SCALE

FF_GAIN

BKCAL_HYS

TRK_IN_D

TRK_VAL

ROUT_IN

Status

BKCAL_IN

OUT_HI_LIM

OUT_LO_LIM

Output Track

TRK_SCALE

Output

ROUT_OUT

OUT

Table 1.L Proportional/Integral/Derivative Block Specifications

Description The Proportional/Integral/Derivative function block provides classic three-mode control function for closed-loop

control applications. When the Process Variable deviates from the Set point, the PID function acts upon the error to move the output in a direction to correct the deviation. PID blocks support cascade applications to compensate for the difference in process time constants of a primary and secondary process measurement. A functional schematic of the block is shown in Figure 1.12 for reference.

Function Notes • Supports Out of Service (OOS), Initialization Manual (IMan), Local Override (LO), Manual (Man), Automatic (Auto),

Cascade (Cas), Remote Cascade (RCas) and Remote-Out (ROut) modes.

• The input (IN) passes through a filter with a time constant (PV_FTIME). The filtered value becomes the Process Variable (PV) to be used with the Set point (SP) in the block's algorithm. A PID algorithm will not integrate, if the limit status of the input (IN) is constant.

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Table 1.L Proportional/Integral/Derivative Block Specifications

Function Notes (cont.)

• The tuning constant used for the Proportional term is GAIN, RESET is used for the Integral term, and RATE is used for the Derivative term. Both RESET and RATE are time constants expressed in seconds. Some controllers use the inverse values of Proportional Band and repeats per minutes for their tuning constants. Users can choose which tuning constants they want to display.

• The TRK_VAL input brings in an external value or uses a constant. The TRK_SCALE values convert the TRK_VAL to a percent of output span value. If the CONTROL_OPTS Track Enable selection is true and TRK_IN_D is true, the converted TRK_VAL replaces the output (OUT), when the block is in Automatic (Auto), Cascade (Cas), Remote Cascade (RCas), or Remote-Out (ROut) mode. The CONTROL_OPTS Track in Manual selection must be true for this to occur in Manual mode. If the actual mode is OOS or IMan, the track request is ignored.

• If the status of TRK_IN_D is Bad, its last usable value will be maintained and acted upon. If the device restarts, losing the last usable value, it will be set to false.

• If the status of TRK_VAL is Bad, the last usable value will be used. If there is no last usable value, the present value of the OUT will be used.

• Use the Obey SP limits if Cas or RCas CONTROL_OPTS to use SP value after limiting in Cas or RCas mode.

• Use the Use PV for BKCAL_OUT CONTROL_OPTS to the PV value for the BKCAL_OUT value.

Parameters (see Appendix A for definitions of each parameter)

ACK_OPTION ALARM_HYS ALARM_SUM ALERT_KEY BAL_TIME BKCAL_HYS BKCAL_IN BKCAL_OUT BLOCK_ALM BLOCK_ERR BYPASS CAS_IN CONTROL_OPTS DV_HI_ALM DV_HI_LIM DV_HI_PRI DV_LO_ALM

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DV_LO_LIM DV_LO_PRI FF_GAIN FF_SCALE FF_VAL GAIN GRANT_DENY HI_ALM HI_HI_ALM HI_HI_LIM HI_HI_PRI HI_LIM HI_PRI IN LO_ALM LO_LIM LO_LO_ALM

LO_LO_LIM LO_LO_PRI LO_PRI MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM OUT_SCALE PV PV_FTIME PV_SCALE RATE RCAS_IN RCAS_OUT RESET ROUT_IN ROUT_OUT

SHED_OPT SP SP_HI_LIM SP_LO_LIM SP_RATE_DN SP_RATE_UP ST_REV STATUS_OPTS STRATEGY TAG_DESC TRK_IN_D TRK_SCALE TRK_VAL UPDATE_EVT

Ratio Block

Figure 1.13 Functional schematic for Ratio function block.

IN_1

BKCAL_IN

CAS_IN

RCAS_IN

TRK_IN_D

TRK_VAL

BKCAL_OUT

RCAS_OUT

BKCAL_OUT

OUT

RCAS_OUT

BKCAL_IN

The Fieldbus Communication Model 1-25

CAS_IN

RCAS_IN

IN_1

Setpoint

SP_RATE_DN SP_RATE_UP

SP_HI_LIM

SP_LO_LIM

Filter

RA_FTIME

Filter

PV_FTIME

Mode

SHED_OPT

Ratio

GAIN

Calc PV

GAIN

Alarm

HI/LO

DEV

Output Track

TRK_SCALE

TRK_IN_D

TRK_VAL

Output

OUT_HI_LIM

OUT_LO_LIM

BAL_TIME

OUT

Table 1.M Ratio Block Specifications

Description The Ratio function block set point is the ratio of its output to its input. A ratio set point of 0.5 produces an output that

is one half of its input. The input (IN_1) is either a wild flow or the output of a blend-pacing controller. The output can be used as the set point for a secondary flow controller. An input (IN) from the secondary measurement is used to calculate the actual ratio, which is displayed as the PV. A functional schematic of the block is shown in Figure 1.13 for reference.

Function Notes • Supports Out of Service (OOS), Initialization Manual (IMan), Local Override (LO), Manual (Man), Automatic (Auto),

Cascade (Cas), and Remote Cascade (RCas) modes.

• The input 1 (IN_1) value to be ratioed passes through a filter with a time constant of RA_FTIME. The filtered value is multiplied by the Set point (SP) and GAIN to become the target output. The GAIN controls the number of zeros in the SP display.

• The input (IN) value is the actual value of the ratioed variable and it passes through a filter with a time constant of PV_FTIME. The filtered IN value is divided by the filtered IN_1 value and the GAIN to become the PV. The units of IN are not PV, but OUT. The units of IN_1 are OUT units divided by PV units.

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Table 1.M Ratio Block Specifications

Function Notes (cont.)

• Use the Act on IR CONTROL_OPTS to select whether to pass initialization requests or act on them locally by changing the SP value. If this option is OFF or to pass, a status of Not Invited (NI) or Initialization Request (IR) at BKCAL_IN will be passed to BKCAL_OUT. The BKCAL_OUT value will be calculated from the value of BKCALC_IN divided by GAIN and IN_1. When the upstream block sends Initialization Acknowledge (IA) status, the block sends the IA status, since its output will now be nearly identical to the value BKCAL_IN. If this option is ON or to act, a status of NI or IR at BKCAL_IN adjusts the SP to balance the output to the value of BKCAL_IN. The IA status is sent as soon as IR is detected. The BKCAL_OUT will not request initialization.

• Use the Balance Ramp CONTROL_OPTS to maintain the ratio SP value, when the block is in Manual (Man) mode. An internal value follows the actual value required to maintain balance. When block mode changes to Automatic (Auto), the internal value ramps to zero contribution in BAL_TIME seconds. If Balance Ramp option is OFF or not used, the ratio SP value immediately changes to follow the changes to the input or output, when the block is in Man mode.

• The TRK_VAL input brings in an external value or uses a constant. The TRK_SCALE values convert the TRK_VAL to a percent of output span value. If the CONTROL_OPTS Track Enable selection is true and TRK_IN_D is true, the converted TRK_VAL replaces the output (OUT), when the block is in Automatic (Auto), Cascade (Cas), or Remote Cascade (RCas) mode. The CONTROL_OPTS Track in Manual selection must be true for this to occur in Manual mode. If the actual mode is OOS or IMan, the track request is ignored.

• If the TRK_VAL replaces the OUT, its status becomes Locked Out with Limits set to Constant. The actual mode goes to LO. The status of BKCAL_OUT, and RCAS_OUT goes to Not Invited (NI), if not already there.

• If the status of TRK_IN_D is Bad, its last usable value will be maintained and acted upon. If the device restarts, losing the last usable value, it will be set to false.

• If the status of TRK_VAL is Bad, the last usable value will be used. If there is no last usable value, the present value of the OUT will be used.

• Use the Obey SP limits if Cas or RCas CONTROL_OPTS to use SP value after limiting in Cas or RCas mode.

• Use the “Use PV for BKCAL_OUT” CONTROL_OPTS to the PV value for the BKCAL_OUT value.

Equation Options If Auto mode, OUT = IN_1 (filtered) x SP x GAIN

PV = IN (filtered) / IN_1 (filtered) / GAIN If IN_1 has non-cascade status, BKCAL_OUT = BKCAL_IN / GAIN / IN_1 (filtered) If IN_1 has cascade status, BKCAL_OUT = BKCAL_IN / GAIN / SP

Parameters (see Appendix A for definitions of each parameter)

ACK_OPTION ALARM_HYS ALARM_SUM ALERT_KEY BAL_TIME BKCAL_IN BKCAL_OUT BLOCK_ALM BLOCK_ERR CAS_IN CONTROL_OPTS DV_HI_ALM DV_HI_LIM DV_HI_PRI DV_LO_ALM

DV_LO_LIM DV_LO_PRI GAIN GRANT_DENY HI_ALM HI_HI_ALM HI_HI_LIM HI_HI_PRI HI_LIM HI_PRI IN IN_1 LO_ALM LO_LIM LO_LO_ALM

LO_LO_LIM LO_LO_PRI LO_PRI MODE_BLK OUT OUT_HI_LIM OUT_LO_LIM OUT_SCALE PV PV_FTIME PV_SCALE RA_FTIME RCAS_IN RCAS_OUT SHED_OPT

SP SP_HI_LIM SP_LO_LIM SP_RATE_DN SP_RATE_UP ST_REV STATUS_OPTS STRATEGY TAG_DESC TRK_IN_D TRK_SCALE TRK_VAL UPDATE_EVT

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The Fieldbus Communication Model 1-27

Device Descriptions and Block Parameters

About Device Descriptions

Device Descriptions (DD) are absolutely critical to the interoperability of fieldbus devices. They define the data needed to establish communications among different fieldbus devices from multiple vendors and with control system hosts. The DD provides an extended description of each object in the User Application Virtual Field Device (VFD).

The Fieldbus Foundation provides Device Descriptions for all standard Function Blocks and Transducer Blocks on a CD-ROM. Manufacturer's provide an “Incremental” DD that references the standard DDs and describes manufacturer specific features such as calibration and diagnostic procedures added to their devices.

Device Description Language

The Device Description Language (DDL) is a structured text language used to write a DDL source file. A DDL source file describes each device function, parameter, and special feature as well as how a field device can interact with a host application and other field devices. A completed DDL source file is converted into a binary formatted DD output file. The DD output file information can be provided in object form in the device itself, or on a removable storage media delivered with the device. A field device's Object Dictionary (OD) can be transferred from a device to a host using standard Fieldbus Message Specification services.

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1-28 The Fieldbus Communication Model

Level 2:

Function

Block

Parameters

Level 3:

Transducer

Block

Parameters

Device Description infrastructure

The Fieldbus Foundation defines a four-level infrastructure for Device Descriptions for the sake of consistency. See Figure 1.14 for a graphical representation of the DD infrastructure.

Figure 1.14 Device Descriptions infrastructure.

Level 1:

Universal

Parameters

Defined by

Fieldbus Foundation

Specification

RESOURCE

TEMP

FLOW

PID

Level 4:

Manufacturer

Specific

Parameters

Defined by

Manufacturer

Resource

Block

Trans ducer

Block

Function

Block

Levels 1, 2, and 3 are the Device Descriptions that the Fieldbus Foundation provides on CD-ROM.

Level 1 consists of Universal Parameters that define common attributes such as Tag, Revision, and Mode. All blocks must include Universal Parameters.

Level 2 consists of Function Block Parameters that define parameters for all standard Function Blocks including the standard Resource Block.

Level 3 consists of Transducer Block Parameters that define parameters for the standard Transducer block. In some cases, the Transducer Block specification may add parameters to the standard Resource Block.

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Level 4 is the Manufacturer Specific Parameters that define the parameters a manufacturer has added to the standard Function Block and Transducer Block parameters. These added parameters will be included on the manufacturer's Incremental DD.

The Fieldbus Communication Model 1-29

Foundation Fieldbus Performance

Foundation Fieldbus is a powerful network providing both communication and distributed control capability. However, fast response is not one of its great capabilities. The screen capture below reflects the time allocated for 18 function blocks to publish their outputs on Fieldbus. The average time is about 40 ms. per published value.

Therefore, in the application reflected in this schedule, you should plan on a loop closure time of on the order of 1 second if you want new data from all devices each time you run the loop calculation.

Part of the reason that fieldbus is slow is that Fieldbus devices operate on very small amounts of current. 10 to 20 ma. per device is typical. This translates into slow computations in the transmitters. It typically takes 100 ms for a fieldbus transmitter to make a new measurement of an input with all the associated calculations completed. Therefore, when attempting to determine the performance of a fieldbus system, please recognize these facts.

Performance Calculation Considerations

Some pressure transmitters will read their transducers and create a new floating point digital readings of the PV every 100 ms. That value can only be read every 40 to 50 milliseconds because of the Fieldbus data rate, and of the Fieldbus protocol.

The data rate is 31.25 Kbps, or 31 bits per millisecond. Very very slow by comparison with ControlNet or Ethernet.

• A minimum Fieldbus message uses 99 bits.

• A minimum response uses 150 bits.

Just to put those messages on the wire takes 8 ms. The protocol says that you must allow time for each device to send nonscheduled messages, in addition to the Publishing of the Precess Variables, that are scheduled. The protocol also says that you must allow significant time for a Fieldbus device to respond to a request for data or information. The result of the slow data rate and the protocol dictate that Fieldbus configuration tools allow 40 to 50 milliseconds for the transmission of data from each Function Block.

Also, many pressure transmitters measures both the pressure and the temperature. If the application dictates that both values must be used, then 80 to 100 milliseconds will be allocated to communicating with those two function blocks, in that one pressure transmitter. Both the Pressure and the Temperature interface with other Fieldbus devices

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1-30 The Fieldbus Communication Model

through independent function blocks, so each require their own 40 to 50 milliseconds.

The 1788-CN2FF operates on the Fieldbus side at the max. speed of the Fieldbus, and at the ControlNet rate on the ControlNet side. Therefore, the 1788-CN2FF is not a limiting factor in a Fieldbus systems performance. When a 1788-CN2FF operates, the Fieldbus side and the CN side run asynchronously. When the CN2FF receives data, it is stored in the CN2FF and is Produced on CN at the NUT rate. Therefore, in a typical CN2FF Fieldbus system, the controller will be receiving a lot of redundant data.

In a PLX system, with a FIM fieldbus interface, the Fieldbus side operates at the Fieldbus data rate, and the controller side operates at the backplane rate, so again, it is not a restriction on the performance of a fieldbus system.

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Chapter

Integrating Fieldbus into Rockwell Automation Logix System

Overview

Background - the goals of integration

The following table summarizes the major areas of consideration that were key to defining the goals for bringing Fieldbus into ProcessLogix.

Table 2.A

Function Goal

Connection of Foundation Fieldbus devices to a Logix system.

Configuration of Foundation Fieldbus devices through Tools system.

Integration of Foundation Fieldbus Devices process, maintenance, and alarm data with notification and display functions in control systems.

Integrate fieldbus devices on an H1 link with Supervisory level ControlNet or Ethernet network, and/or the I/O ControlNet network.

Integrate configuration of fieldbus devices through the NetLinx strategy.

Integrate data from fieldbus devices into Detail, Group, Trend, Maintenance, and Alarm displays through the Station application in ProcessLogix as well as the Monitoring tab of the Control Builder application.

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2-2 Integrating Fieldbus into Rockwell Automation Logix System

Fieldbus Integrated Architecture

As shown in Figure 2.1, Foundation Fieldbus devices can be connected or integrated into a Rockwell Logix system. ProcessLogix, Release 400.0 and later can be configured with a Fieldbus Interface Module (FIM). The FIM serves as the communication gateway between the Supervisory ControlNet/Ethernet and/or I/O ControlNet network and the Foundation Fieldbus H1 communications medium. It works with a Remote Termination Panel (RTP) for connecting and powering up to two fieldbus H1 links.

For applications that require a more highly distributed connection and/or communications directly with a PLC5 or ControlLogix 5500 processor, you can us the 1788-CN2FF ControlNet to Foundation Fieldbus Gateway device.

Figure 2.1 Logix system architecture for Fieldbus integration.

Ethernet (TCP/IP)

Redundant

ProcessLogix

Station

ProcessLogix

Servers

PLC 5

Controller

PLC5/C Controller

Supervisory ControlNet/Ethernet

ProcessLogix and ControlLogix

Data Highway +

1771 Remote I/O

SLC Controller

ControlNet

COMM

STATUS

ControlNET

POWER

A#24

Flex Ex

Logix5550

RUN I/O

RS232

BAT

PROGRUN

REM

DH+/RIO

ControlNET

B#15

A#24

CH ACH B

Transmitter

ControlNET

A#24

ControlNet

Pressure

DEVICENET

1757-FIMRTP

FIM

1788-CN2FF

FOUNDATION

Fieldbus

PLC 5

Controller

PLC5/C Controller

ControlNET

Logix5550

RUN I/O

POWER

RS232

A#24

BAT

OK A B

PROGRUN

REM

Data Highway +

1771 Remote I/O

Redundant Controllers

DH+/RIO

ControlNET

B#15

A#24

CH ACH B

SLC Controller

ControlNet

COMM

STATUS

DEVICENET

ControlNET

POWER

A#24

I/O ControlNet

ProcessLogix and ControlLogix

DH+/RIO

ControlNET

POWER

A#24

ControlNET

Logix5550

RUN I/O

RS232

B#15

A#24

BAT

CH ACH B

PROGRUN

REM

ControlNet

Flex Ex

Pressure

Transmitter

DH+/RIO

ControlNET

Logix5550

RUN I/O

RS232

B#15

A#24

BAT

CH ACH B

PROGRUN

REM

DEVICENET

1757-FIMRTP

FIM

1788-CN2FF

FOUNDATION

Fieldbus

43190

ControlNET

DEVICENET

A#24

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Integrating Fieldbus into Rockwell Automation Logix System 2-3

Fieldbus Interface Modules - The Key to an Integrated System

The 1757-FIM, Fieldbus Interface Module is the key to bringing the Foundation Fieldbus system into a ProcessLogix system. The FIM has been designed to operate as a stand-alone Foundation Fieldbus interface or as a bridge between the ProcessLogix control environment and the fieldbus devices. It supports both the publish/subscribe and the client/server communication methods to communicate with fieldbus function blocks. The control connections must be downstream only.

The FIM is a doublewide module that plugs into a non-redundant Controller or remote I/O chassis. It connects up to two Fieldbus H1 links through a companion Remote Termination Panel (RTP). These independent links each have their own link schedule, link master and time master functions. The RTP is designed for DIN rail mounting within an enclosure. It optionally accepts a 24 Vdc input from an external power supply to provide low-level power to fieldbus devices on the H1 links.

The Fieldbus Interface Module functions as a dual network bridge using a dynamic data cache to facilitate the exchange of data between the ControlNet/Ethernet network and the Fieldbus H1 links. It supports both publish/subscribe and client/server communications methods to implement control connections between ProcessLogix function blocks and fieldbus function blocks.

FIM capability includes converting ProcessLogix value-status structure to fieldbus value-status by mapping similar fields to one another and defaulting others. This means ProcessLogix can monitor fieldbus control functions, fully integrate with control functions, or provide a combination that includes using fieldbus based control as backup for selected ProcessLogix control functions.

The FIM uses low and high priority send queues to make sure that publish/subscribe data normally used for control is processed before less important display access data. Publish/subscribe requests are placed in the high priority send queue and client/server requests are placed in the low one.

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2-4 Integrating Fieldbus into Rockwell Automation Logix System

Configuration Tools

1788-CN2FF Linking Device

The ControlNet-to-Foundation Fieldbus H1 linking device (1788-CN2FF) connects a ControlNet™ network with one or two F

OUNDATION Fieldbus H1 (Fieldbus) networks. Each H1 network

consists of multiple Fieldbus devices. Each field device has one or more function blocks. Each function block performs an elementary control function such as analog input, analog output, discrete input, or discrete output. The ControlNet network consists of controllers, such as PLC® processors, HMIs, drives, I/O devices, and so on. The linking device has two broad functions, supporting the following:

• closed-loop control

• configuration and monitoring

ControlBuilder

The ProcessLogix R400.0 Control Builder application supports integral configuration of fieldbus function blocks with ProcessLogix function blocks to incorporate fieldbus devices in a unified ProcessLogix Control Strategy. This means ProcessLogix function blocks and fieldbus function blocks can be easily interconnected, so control can reside on the fieldbus link, in the Control Processor/Control Execution Environment (CEE), or cascaded from CEE to the fieldbus device.

An integrated Fieldbus Library Manager lets users read the manufacturer's Device Descriptions for fieldbus devices to be tied to an H1 Link and create individual templates for each fieldbus device including their function blocks. The fieldbus device templates will reside in the Engineering Repository Database for ProcessLogix. Once a fieldbus device template is created, the fieldbus device is easily associated with the appropriate FIM H1 Link through the Project tab in Control Builder. The following figure shows how icons are used to readily identify FIM, H1 Links, and fieldbus devices in the Control Builder Project tab.

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Icon for function block

representing FIM hardware

Icon for function block representing fieldbus device to be tied to one of the H1 Links

Integrating Fieldbus into Rockwell Automation Logix System 2-5

Figure 2.2 Project tab in Control Builder has new icons for Fieldbus components.

Icons for H1 Links associated with FIM11

1757-FIM

Icons for fieldbus functio blocks associated with fieldbus device

Foundation Fieldbus Configuration Tool

To configure the 1788-CN2FF, you use 1788-FFCT Configuration Software tool. This Fieldbus configuration software uses RSLinx to connect via ControlNet (supports redundant ControlNet) to any CN2FF devices on the Network.

Using the FFCT software you can configure any Foundation Fieldbus device, as well as view, display, and monitor all Foundation Fieldbus parameters. You can also use this tool to setup the data exchange to PLCs, ControlLogix, and ProcessLogix processors.

Centralized Operator Interface

The ProcessLogix R400.0 Station application includes Detail Displays dedicated to the configured FIM, associated H1 Links, fieldbus device, and associated fieldbus function blocks. They provide access to the same parameters that are accessible through the control charts and configuration forms in the Monitoring tab of Control Builder. This includes manufacturer specific parameters, where applicable.

The reporting of alarm conditions and retrieval of process data for inclusion in group, trend, history, and schematic displays is closely integrated with ProcessLogix's existing notification management system. The existing access authorization levels apply and will take precedence over fieldbus restrictions specified in Device Descriptions.

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2-6 Integrating Fieldbus into Rockwell Automation Logix System

Network Management description

Network Management provides the following capabilities for managing the communication system of a fieldbus device.

• Loading a Virtual Communication Relationship (VCR) list or single entries in this list; (A VCR represents a communication channel through the complete communication stack.)

• Configuring the communication stack;

• Loading the Link Active Schedule (LAS);

• Monitoring performance; and

• Monitoring fault detection.

The collection of managed variables is called the Network Management Information Base (NMIB).

System Management Description

System Management provides the following functions to coordinate the operation of various devices in a distributed fieldbus system.

• Assigning node addresses for devices;

• Synchronizing the application clock;

• Distributing application scheduling across the link; and

• Providing support for locating application tags.

It provides the needed facilities for bringing new devices on the link to an operational state and for controlling the overall system operation. Information, which is used to control system management operation, is organized as objects stored in the System Management Information Base (SMIB).

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Integrating Fieldbus into Rockwell Automation Logix System 2-7

About the Device Object

The device object represents a physical device entity connected to the fieldbus link. It provides access to the device's Network Management (NM) and System Management (SM) parameters. The client/server VCR is configured in the FIM to access the Management Interface Base (MIB) of the device as soon as it joins the network. The Control Builder does not configure the MIB VCR explicitly. Once the MIB VCR is configured and opened, FIM retrieves MIB information, SMdirectory, and NM directory. Knowledge of these directories allows FIM to transform writes into domain object variables into proper sequence of domain download operations. The SM directory is also used to determine the number of application VFDs. The NM directory is key in attempting to configure VCRs to access Function Block Application Process VFDs in the device.

About the VFD Object

The Virtual Field Device object represents an application VFD and provides parameter access to that VFD. Each physical device may have one or more application VFDs. The FIM attempts to build a client/server VCR to every VFD in the device, when it is added to the network. If the VCR configuration is successful, the FIM obtains VFD and resource identification from the device's VFD. During device download, you can overwrite VCR configuration used to access VFD parameters through the Control Builder application.

Fieldbus Device Analog Input Integration

A user can functionally wire the output from an Analog Input (AI) function block in a fieldbus device residing on an H1 link to the input of a regulatory control type function block contained in a Control Module in the ProcessLogix Control Builder application. The Proportional, Integral, Derivative (PID) function block is a typical regulatory control type function block.

The Fieldbus Library Manager (FLM) in ProcessLogix R400.0 Control Builder makes this possible. The FLM reads the manufacturer's DD for the fieldbus device and creates a device template that is included in the Project tab of Control Builder. The device template includes the device's fieldbus function blocks, so it can be configured and integrated with control strategies through Control Builder.

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2-8 Integrating Fieldbus into Rockwell Automation Logix System

Figure 2.3 shows a simplified functional diagram of how the output from an Analog Input function block in a fieldbus compliant transmitter is integrated with a PID function block in a Control Module that is assigned and loaded to the CEE in the Control Processor Module (CPM).

Figure 2.3 Integration of fieldbus device analog input signal with ProcessLogix control strategy

CPM/CEE

FIM

Fieldbus Device

Transducer

Analog

Input

PID

OUT

AOC

FIM

AOC = Analog Output Channel CEE = Control Execution Environment CM = Control Module CPM = Control Processor Module FIM = Fieldbus Interface Module OP = Output PID = Proportional, Integral, Derivative PV = Process Variable

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Fieldbus Analog Input data manipulation

When the OUT from the fieldbus analog input function block is wired to the PV input for a PID function block, the Control Builder creates a CEE input agent to handle the analog input from the fieldbus block. The block-like input agent maps the data structure (DS-65) of the OUT parameter to the ProcessLogix PV with status parameter. It interprets the value portion in fieldbus terms and converts it to ProcessLogix representation. The floating-point representation is identical, in most cases, but the fieldbus +/-infinity value must be converted to a ProcessLogix representation.

If the fieldbus status byte indicates “BAD”, the value must be converted to Not a Number (NaN) for ProcessLogix representation.

Integrating Fieldbus into Rockwell Automation Logix System 2-9

The fieldbus data quality of good, bad, and uncertain is mapped to the appropriate ProcessLogix parameter of PVSTS, PVSTSFL.NORM, PRSTSFL.BAD, or PVSTSFL.UNCER.

The fieldbus limit indications of no-limit, limited-low, limited-high, and constant are mapped to the same four indications for ProcessLogix. The fieldbus data substatus indicator maps only the limited number of substatus conditions that have corresponding ProcessLogix indications.

The handshaking provided by the substatus associated with Good [cascade] status is not supported from an upstream Fieldbus device. This means that control may not originate in the field and cascade into the ProcessLogix Controller.

Fieldbus device Analog Output or PID integration

A user can functionally “wire” the output from a regulatory control type function block contained in a Control Module in the ProcessLogix Control Builder application to the input of an Analog Output (AO) or Proportional, Integral, Derivative (PID) function block in a fieldbus device residing on an H1 link. The Proportional, Integral, Derivative (PID) function block is a typical ProcessLogix regulatory control type function block. The Fieldbus Library Manager (FLM) included in the R400 Control Builder makes this possible. The FLM reads the manufacturer's DD for the fieldbus device and creates a device template that is included in the Project tab of Control Builder. The device template includes the device's fieldbus function blocks, so it can be configured and integrated with control strategies through Control Builder.

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2-10 Integrating Fieldbus into Rockwell Automation Logix System

Figure 2.4 shows a simplified functional diagram of how the output from a PID function block in a Control Module that is assigned and loaded to the CEE in the Control Processor Module (CPM) is integrated with an Analog Output function block in a fieldbus compliant device.

Figure 2.4 Integration of a Fieldbus device analog output signal with ProcessLogix control strategy

CPM/CEE

AIC

DACQ

PID

BACKCALIN

FIM

Fieldbus Device

CAS_IN

RCAS_IN

FIM

Analog Output

RCAS_IN

BKCAL_OUT

RCAS_OUT

OUT

Transd ucer

CAS_IN

AIC = Analog Input Channel BACKCALIN = Back Calculation Input BKCAL_OUT = Back Calcul ation Output CAS_IN = Cascade Input CEE = Control Execution Environment CM = Control Module CPM = Control Processor Module DACQ = Data Acquistion FIM = Fieldbus Interface Module OP = Output PID = Proportional, Integral, Derivative PV = Process Variable RCAS_IN = Remote Cascade Input RCAS_OUT = Remo te Cascade Output

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Integrating Fieldbus into Rockwell Automation Logix System 2-11

Figure 2.5 shows a simplified functional diagram of how the output from a PID function block in a Control Module that is assigned and loaded to the CEE in the Control Processor Module (CPM) is integrated with a cascaded Proportional, Integral, Derivative function block in a fieldbus compliant device.

Figure 2.5 Integration of fieldbus device PID control with ProcessLogix control strategy

CPM/CEE

FIM

Fieldbus Device

Transd ucer

Analog

Input

OUT

CAS_IN

RCAS_IN

ROUT_IN

BKCAL_ IN

TRK_I N_D

TRK_VAL

FF_VAL

AIC

DACQ

PID

FIM

RCAS_IN

BKCAL_OUT

RCAS_OUT

OUT

ROUT_OUT

PID

CAS_IN

RCAS_IN

BACKCALIN

CAS_IN

Analog Output

BKCAL_OUT

RCAS_OUT

OUT

Transd ucer

AIC = Analog Input Channel BACKCALIN = Back Calculation Input BKCAL_IN = Back Calculation Input BKCAL_OUT = Back Calculation Output CAS_IN = Cascade Input

CEE = Control Execution Environment CM = Control Module CPM = Control Processor Module DACQ = Data Acquistion FIM = Fieldbus Interface Module

OP = Output PID = Proportional, Integral, Derivative PV = Process Variable RCAS_IN = Remote Cascad e Input RCAS_OUT = Remote Cascade Output ROUT_OUT = Remo te Out Output

Fieldbus Analog Output or PID data manipulation

When the OP from the PID function block is wired to the CAS_IN input for a fieldbus Analog Output or Proportional, Integral, Derivative function block, the Control Builder automatically creates a CEE output agent to handle the analog output to the fieldbus block.

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2-12 Integrating Fieldbus into Rockwell Automation Logix System

The block-like output agent maps the ProcessLogix OP with status parameter to the fieldbus data structure (DS-65) of the CAS_IN parameter. It interprets the value portion in ProcessLogix terms and converts it to fieldbus representation. The floating-point representation is identical, in most cases, but the ProcessLogix +/-infinity value must be converted to a fieldbus representation. If the status of OP is “BAD”, its value must be converted from NaN to zero (0.0) for fieldbus representation or it may retain its previous good value, as long as the fieldbus status byte indicates “BAD”.

The CEE output agent also accepts a single BKCAL_OUT parameter with the fieldbus data structure (DS-65) and maps it to the BACKCALIN parameter of the PID block in ProcessLogix terms.

ATTENTION

The ProcessLogix Control Builder application automatically makes the appropriate back calculation connections during configuration and the connections are “hidden” in Control Chart views.

Like the FIM, the output agent supports both publish/subscribe and client/server communication methods. The publish/subscribe method allows the FIM to appear as a fieldbus device on the H1 link. The FIM publishes the output (OP) for subscribing fieldbus device resident blocks such as Analog Output and Proportional, Integral, Derivative (PID) through their CAS_IN parameter input connection. This connection is generally used when the downstream control block is in the Cas (cascade) mode. This means that the fieldbus block's BKCAL_OUT parameter is published by the downstream block and subscribed to by the FIM.

The client/server method allows the FIM to appear as a computing device on the H1 link. The FIM writes the output (OP) to be read by fieldbus device resident blocks such as Analog Output and Proportional, Integral, Derivative (PID) through their RCAS_IN parameter input connection. This connection is generally used when the downstream control block is in the RCas (Remote Cascade) mode. This means that the fieldbus block's BKCAL_OUT parameter is written by the downstream block and read by the FIM.

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The client/server method also allows the FIM to function in a Direct Digital Control (DDC) mode or the Remote Out mode in fieldbus terms. In this case, the FIM writes the output to be read by the fieldbus PID block though its ROUT_IN parameter input connection. In turn, the PID block publishes the ROUT_OUT or back calculation output value for the subscribing FIM.

Integrating Fieldbus into Rockwell Automation Logix System 2-13

The ProcessLogix data quality is converted to fieldbus data quality. The ProcessLogix Good indication is represented as fieldbus Good(Cascade).

The ProcessLogix limit indications of no-limit, limited-low, limited-high, and constant are mapped to the same four indications for fieldbus.

The ProcessLogix control initialization indicators map only to the limited number of substatus conditions that have corresponding indications in fieldbus Good(Cascade).

Fieldbus device Discrete Input integration

A user can functionally “wire” the output from a Discrete Input (DI) function block in a fieldbus device residing on an H1 link to the input of a Device Control (DEVCTL) function block or other block with a digital input contained in a Control Module in the ProcessLogix Control Builder application. The Fieldbus Library Manager (FLM) in ProcessLogix R400.0 Control Builder makes this possible. The FLM reads the manufacturer's DD for the fieldbus device and creates a device template that is included in the Project tab of Control Builder. The device template includes the device's fieldbus function blocks, so it can be configured and integrated with control strategies through Control Builder.

Figure 2.6 shows a simplified functional diagram of how the output from an Discrete Input function block in a fieldbus compliant transmitter is integrated with a Device Control (DEVCTL) function block in a Control Module that is assigned and loaded to the CEE in the Control Processor Module (CPM).

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2-14 Integrating Fieldbus into Rockwell Automation Logix System

Figure 2.6 Integration of fieldbus device digital input signal with ProcessLogix control strategy

DI[1]

Device

Control

CPM/CEE

FIM

DO[1]

DOC

FIM

Fieldbus Device

Transducer

Digital

Input

OUT

CEE = Control Execution Environment CM = Control Module CPM = Control Processor Module FIM = Fieldbus Interface Module DOC = Digital Output Channel

Fieldbus Discrete Input data manipulation

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When the OUT from the fieldbus Discrete Input function block is wired to the DI[n] input for a DEVCTL function block, the Control Builder creates a CEE discrete input agent to handle the digital input from the fieldbus block. The block-like discrete input agent maps the data structure (DS-66) of the OUT parameter to the ProcessLogix DI[n] with status parameter. It interprets the value portion in fieldbus terms as a Boolean for Discrete Input (DI) block and as the appropriate multi-state representation for special fieldbus Device Control (DC) block. The value is converted and represented in ProcessLogix at the output.

The discrete input agent accepts inputs from either a published parameter or a client/server read parameter, depending upon the communication method used.

The fieldbus data quality of good(cascade), good(non-cascade), bad, and uncertain is mapped to the appropriate ProcessLogix parameter for good, bad, and uncertain.

Integrating Fieldbus into Rockwell Automation Logix System 2-15

Fieldbus device Discrete Output data integration

A user can functionally “wire” the output from a discrete process or control value producing ProcessLogix function block like Device Control to the input of a Discrete Output block in a fieldbus device residing on an H1 link. The Fieldbus Library Manager (FLM) included in the R400 Control Builder makes this possible. The FLM reads the manufacturer's DD for the fieldbus device and creates a device template that is included in the Project tab of Control Builder. The device template includes the device's fieldbus function blocks, so it can be configured and integrated with control strategies through Control Builder.

Figure 2.7 shows a simplified functional diagram of how the output from a Device Control (DEVCTL) function block in a Control Module that is assigned and loaded to the CEE in the Control Processor Module (CPM) is integrated with a Discrete Output function block in a fieldbus compliant device.

Figure 2.7 Integration of fieldbus device digital output signal with ProcessLogix control strategy

DIC

BACKCALIN

CPM/CEE

FIM

PVFL

FIM

DI[1]

RCAS_IN

Device

Control

DO[1]

CAS_IN

Fieldbus Device

CAS_IN_D

RCAS_IN_D

Digital Output

BKCAL_OUT_D

RCAS_OUT_D

OUT_D

Trans duc er

BACKCALIN = Back Calculation Input BKCAL_OUT_ D = Back Calculat ion Output Discrete CAS_IN_D = Cascade Input Discrete CEE = Control Execution Environment CM = Control Module CPM = Control Processor Module

DIC = Digital Input Channel FIM = Fieldbus Interface Module OP = Output PVFL = Proc ess Variable Flag RCAS_IN_D = Remote Cascade Input Discrete RCAS_OUT_D = Remote Cascade Output Discre te

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2-16 Integrating Fieldbus into Rockwell Automation Logix System

Fieldbus Discrete Output data manipulation

When the DO[n] from the Device Control (DEVCTL) function block is wired to the CAS_IN_D input for a fieldbus Discrete Output function block, the Control Builder automatically creates a CEE output agent to handle the discrete output to the fieldbus block. The block-like output agent maps the ProcessLogix DO[n] with status parameter to the fieldbus data structure (DS-66) of the CAS_IN_D parameter. It interprets the value portion in ProcessLogix terms and converts it to fieldbus representation.

The CEE output agent also accepts a single BKCAL_OUT_D parameter with the fieldbus data structure (DS-66) and maps it to the BACKCALIN parameter of the DEVCTL block in ProcessLogix terms.

It sends the outgoing “control signal” either to a subscribed parameter or a client/server written parameter through the CAS_IN_D or RCAS_OUT_D connection. It can optionally receive the backcalculation signal from either the corresponding published parameter or client/server read parameter.

The ProcessLogix data quality is converted to fieldbus data quality. The ProcessLogix Good indication is represented as fieldbus Good(Cascade).

The ProcessLogix control initialization indicators map only to the limited number of substatus conditions that have corresponding indications in fieldbus Good(Cascade).

Interface Connections Summary

Since the downstream action with the upstream feedback is the same for all fieldbus blocks, there are essentially the following six types of interface connections through the FIM.

• Analog process value into the FIM.

• Discrete process value into the FIM.

• Analog process output from the FIM.

• Discrete process output from the FIM.

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• Analog process output from the FIM with backcalculation feedback.

Integrating Fieldbus into Rockwell Automation Logix System 2-17

• Discrete process output from the FIM with backcalculation feedback.

Bit types 5 and 6 described in Table 2.B support publish/subscribe communications in Cascade mode or client/server communications in Remote Cascade mode. And, the analog values can also be used in the Remote Out mode.

Fieldbus also supports direct device-to-device (peer-to-peer) publish/subscribe connections independent of the FIM. The FIM can also monitor (subscribe to) the data published between the functions blocks of these fieldbus devices.

Fieldbus status data details

According to Foundation Fieldbus specifications, every fieldbus function block input and output connection must support a status byte that provides the following status indications.

• Data Quality (usability)

• Bad Data Cause

• Degraded Data Cause

• Limit Conditions

• Cascade Control Initialization, Rejection

• Fault-State Initiation, Indication

• Local Override Indication

• Worst Case Alarm Indication

• Upstream Block Class Identification

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2-18 Integrating Fieldbus into Rockwell Automation Logix System

The status byte structure consists of a 2-bit quality, most significant bit, field; a 4-bit substatus field; and a 2-bit limits, least significant bit, field. The following table provides a breakdown of bit assignments for general reference. The value of the quality field determines the applicable substatus field indication.

Table 2.B Breakdoun of bit assignments

Bit Quality Substatus, if Quality field is Limits

BAD UNCERTAIN GOOD

(Non-Cascade)

GOOD (Cascade)

(1)

0 BAD Data Quality Non-Specific Non-Specific Non-Specific Non-Specific No Limits

(1)

1UNCERTAIN Data

Quality

2 GOOD

(Non-Cascade)

Configuration Error Last Usable Value Active Block Alarm Initialization

Acknow-ledge (IA)

Not Connected Substitute Active Advisory

Alarm

Initialization Request (IR)

Low Limit

High Limit

Data Quality

3 GOOD (Cascade)

Data Quality

4 Sensor Failure Sensor Conversion

5 No Communication, with

6 No Communication, with

Device Failure Initial Value Active Critical

Alarm

Unacknow-ledged

Last Usable Value

Not Accurate

Engineering Unit Range Violation

Block Alarm

Unacknow-ledged Advisory Alarm

Sub-Normal Unacknow-leged

no Last Usable Value

Critical Alarm

Not Invited (NI) Constant

Not Selected (NS)

Do Not Select (DNS)

Local Override (LO)

7 Out-Of-Service Fault-State Active (FSA)

8 Initiate Fault-State (IFS)

(1)

The Good (non-cascade) substatus is used by output connections for fieldbus blocks such as Analog Input and Discrete Input. The Good (cascade) substatus is used by output connections for fieldbus blocks such as PID. Both of these substatuses are converted to the single ProcessLogix data quality of Good.

Fieldbus Status Indications

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See Appendix B for list of possible display indications associated with a given fieldbus status.

Integrating Fieldbus into Rockwell Automation Logix System 2-19

Control Mode Interaction

Fieldbus Block Modes Versus Processlogix Modes

Every fieldbus function block including Resource and Transducer blocks contain the MODE_BLK parameter. This structured parameter consists of the Actual, Target, Permitted, and Normal modes. Refer to About Modes of Operation on page 1-8 for descriptions of the eight modes.

For use within ProcessLogix, the structure of the MODE_BLK parameter is expanded to add MODE to the existing Actual, Target, Permitted, and Normal modes as outlined in Table 2.C.

Table 2.C Mode Descriptions

ProcessLogix Mode Structure

MODE Enumeration Write Only

MODE.TARGET Enumeration Read/Write

Data Type Description FIM Action

ProcessLogix style mode enumeration MAN, AUTO, CAS, NORMAL, BCAS, NONE

Target mode OOS, MAN, AUTO, CAS, RCAS, ROUT

The FIM captures all writes to MODE and maps valid changes to MODE.TARGET.

If the value NORMAL is written to the MODE.TARGET, the FIM replaces it with the value from MODE.NORMAL.

MODE.ACTUAL Enumeration Read Only

Actual Mode OOS, IMAN, LO, MAN, AUTO, CAS, RCAS, ROUT

MODE.PERMITTED Bitstring Read/Write

Permitted mode MAN, AUTO, CAS, RCAS, ROUT OOS is always permitted

MODE.NORMAL Enumeration Read/Write

Normal mode MAN, AUTO, CAS, RCAS, ROUT OOS is not Normal

If a new MODE.NORMAL value is entered, it is validated against the MODE.PERMITTED values.

Table 2.D shows how ProcessLogix modes are mapped to fieldbus ones.

Table 2.D Mapping ProcessLogix Modes to Fieldbus

ProcessLogix Mode Fieldbus Mode Comment

MAN Man

AUTO Auto

CAS Cas

NORMAL Normal When setting as target mode, read MODE.NORMAL value and write to MODE.TARGET.

BCAS Error Not used in fieldbus blocks. Attempt to set to target is illegal.

NONE Error Not used in fieldbus blocks. Attempt to set to target is illegal.

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2-20 Integrating Fieldbus into Rockwell Automation Logix System

Control Mode Priorities and Indications

Table 2.E shows the 2-character and 4-character mode indications to be used in operating displays and lists the mode priorities based on several interpretations. The Priority Order interpretation is based on the Out-of-Service mode being serviced over all others. The Control Order interpretation is based on the traditional control engineer's concept that Cascade is a higher mode of operation than Automatic, Automatic is a higher mode of operation than Manual, and so on. The Dominance Order interpretation is based on Foundation Fieldbus special rules for modes dominating one another. For example, Out-of-Service dominates over Manual, Manual dominates over Remote Out, and Remote Out dominates over Remote Cascade. This is relevant, if multiple mode bits are set in the target (or normal) mode bitstrings.

A block uses the concept of priority to compute an actual mode that is different than the target mode, and to determine if the particular actual mode allows write access.

Table 2.E 2-character and 4-character mode indications

Mode Mode Abbreviation Priority Interpretation

2-Character 4-Character Priority Order

(8=highest)

Out-of-Service OS OOS 8 1 6

Initialization Manual IM IMan 7 2 —

Local Override LO LO 6 3 —

Manual M Man 5 4 5

AutoAAuto451

Cascade C Cas 3 6 2

Remote Cascade RC RCas 2 7 3

Remote Output RO ROut 1 8 4

TIP

The ProcessLogix software installation wizard for

Control Order (8=highest)

Dominance Order (6=Highest)

Server includes a dialog box for choosing the desired mode acronyms. Select the Fieldbus acronyms radio button to use the mode abbreviations listed above in the Station displays.

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Integrating Fieldbus into Rockwell Automation Logix System 2-21

While every block type or block instance does not need to support all eight modes, all eight indicator bits are present in the database. The mode bit assignments are listed in Table 2.F.

Table 2.F Mode Bit Assignments

Bit = Mode

0 (LSB) = Remote Output (ROut)

1 = Remote Cascade (RCas)

2 = Cascade (Cas)

3 = Automatic (Auto)

4 = Manual (Man)

5 = Local Override (LO)

6 = Initialization Manual (IMan)

7 (MSB) = Out of Service (OOS)

Rotary Switch Model versus Toggle Switch Model

The Fieldbus Foundation supports both the Rotary Switch and the Toggle Switch models of mode operation. The Rotary Switch model supports only one mode request at a time. For example, an operator can request OOS, Man, Auto, Cas, RCas, or ROut. It has no memory of previous target modes.

The Toggle Switch model supports more than one mode request at a time. For example, an operator can request Manual override of Cascade, Manual override of Remote Cascade, and so on.

ProcessLogix supports the Rotary Switch model as well as the following two instances of the Toggle Switch model.

• An operator may request the Cas mode at the same time the

RCas mode is requested.

• An operator may request the Cas mode at the same time the

ROut mode is requested.

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ProcessLogix also ignores the following illegal mode combinations as defined by the Fieldbus Foundation.

• If ROut is set, RCas may not be set. If it is set, it will be ignored.

• The Auto and Man bits must always be of opposite states. If

neither Auto nor Man or both are set, and the ROut, RCas, or Cas mode is set, Auto mode will be assumed with Man cleared. Likewise, If neither Auto nor Man or both are set, and neither ROut, RCas, nor Cas mode is set, Man mode will be assumed with Auto cleared. For the OOS mode, the Man bit should be set unless it is not permitted. If Man is not permitted, the Auto bit should be set unless it is not permitted. If neither Auto nor Man is permitted, the OOS bit should be set.

IMPORTANT

An operator needs an access level of ENGR or higher to invoke the OOS mode or to return a block to an in-service mode.

ProcessLogix adheres to the following additional rules for setting fieldbus target mode bits in Table 2.G for its MODE supported subset of combinations.

Table 2.G Additional rules for setting fieldbus target mode bits

Fieldbus Mode Rule

OOS When setting as the target mode, obtain the target mode, preserve the Auto and Man bits, set

the OOS bit, and optionally reset all the other bits. Reject the request, if the access level is not ENGR or higher.

IMan This is a Read Only parameter and can not be set as the target mode. Never set the IMan as the

target mode.

LO This is a Read Only parameter and can not be set as the target mode. Never set the LO as the

target mode.

Man When setting as the target mode, set the Man bit and reset all the other bits. Reject the

request, if the current mode is OOS and the access level is not ENGR or higher.

Auto When setting as the target mode, set the Auto bit and reset all the other bits. Reject the

request, if the current mode is OOS and the access level is not ENGR or higher.

Cas When setting as the target mode, set both Cas and Auto bits and reset all the other bits. Reject

the request, if the current target mode is OOS and the access level is not ENGR or higher.

RCas When setting as the target mode, set both RCas and Auto bits and reset all the other bits.

ROut When setting as the target mode, set both ROut and Auto bits and reset all the other bits.

Normal When setting as the target mode, read the MODE.NORMAL value and write to the

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Reject the request, if the current target mode is OOS and the access level is not ENGR or higher.

MODE.TARGET. Reject the request, if the current target mode is OOS and the access level is not ENGR or higher.

Integrating Fieldbus into Rockwell Automation Logix System 2-23

Display indications and mode calculation

The fieldbus mode indications for actual mode and composite actual/target modes will appear in the following formats on Station displays as shown in Table 2.H.

Table 2.H Fieldbus mode indications

Format Description Examples

Remote Cascade

Remote Out

a Satisfied in mode a; actual same

a (t) In mode a; not satisfied in higher

The block mode calculation of actual mode considers the input parameter status attributes, input values, and resource state as represented graphically in Figure 2.8.

Figure 2.8 Block mode calculation summary

Determine

Host Timeout

Shed Option

Cascade

as target.

target mode t.

Actual and Target Mode Calculation

Target Mode

OOS, MAN, AUTO, CAS, RCAS, ROUT

MAN (A), CAS (RC), IM (A), LO (CAS), AUTO (M), CAS (M)

Mode

Actual Mode and Target

Primary Input

Back Calculation Input

Resource State

Block Specific Inputs

See Appendix C for list of conditions, which will change the mode in order of priority with Good (Non-Cascade) status on input parameter as the lowest priority.

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2-24 Integrating Fieldbus into Rockwell Automation Logix System

Link and Block Schedules

Link Active Scheduler (LAS)

All links must have a Link Active Scheduler (LAS). The LAS operates at the data link layer as the bus arbiter for the link. It dynamically provides the following functions.

• Recognizes and adds new devices to the link.

• Removes non-responsive devices from the link.

• Distributes Data Link and Link Scheduling time on the link. The

data link layer synchronizes the network-wide Data Link Time. Link scheduling time is a link specific time represented as an offset from Data Link Time. It is used to indicate when the LAS on each link begins and repeats its schedule. System Management uses it to synchronize function block execution with the data transfers scheduled by the LAS.

• Polls devices for buffered data at scheduled transmission times.

• Distributes a priority-driven token to devices between scheduled

transmissions.

Any device on the link may become the LAS as long as it is capable. The devices that are capable of becoming the LAS are called Link Master devices. All other devices are referred to as Basic devices.

The FIM is Link Master capable and supports both a primary and a backup link schedules. It is designated as the primary Link Master.

Upon startup or failure of the existing LAS, the Link Master devices on the link bid to become the LAS. The Link Master that wins the bid begins operating as the LAS immediately upon completion of the bidding process. Link Masters that do not become the LAS act as basic devices when viewed by the LAS. They also act as LAS backups by monitoring the link for failure of the LAS, and by bidding to become the LAS when a LAS failure is detected.

ATTENTION

If a LAS is too large to fit in the active Link Master capable device, the user must reconfigure the device to become a Basic one through Control Builder, and restart the device to initiate the change.

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Integrating Fieldbus into Rockwell Automation Logix System 2-25

Link Schedule

The Link Schedule is the overall schedule for the link. It includes both the link data transfer and the device function block execution schedules. An independent Link Schedule is provided for the FIM interface port for each link. A backup Link Schedule is provided for all Link Master capable devices on the link.

The link data transfer schedule is derived from the portion of the link schedule that deals with publication of parameters. The Control Builder (CB) provides a default link schedule of publications and function block execution phasing based on the function block connections in the user configured control strategy. The basis for the link schedule is this link's content from all currently loaded Control Modules (CM). Execution phasing is based solely on function block existence in the CM. Order of execution is based on the order in CM (ORDERINCM) parameter for each block. Publications are based on inter-device function block connections and device to ProcessLogix or ProcessLogix to device function block connections. The following publication rules apply.

• Function block publications appear in the link data transfer

schedule in the order specified by their ORDERINCM parameters. (Duplicate values of ORDERINCM may produce indeterminate ordering of those blocks involved.)

• If the user changes the sequence of execution order for function

blocks in a schedule, the ORDERINCM parameters of the involved function blocks are appropriately adjusted.

• Publication of each output is scheduled immediately after

execution of the function block that produces the value, considering inter-publication delays and potential conflicts.

• Blocks publish, if their output is connected to an input in

another device or the FIM.

• No unneeded time delay is allowed in the default link data

transfer schedule.

• The macrocycle is the least common multiple of the execution

periods of all the CMs involved in the link data transfer schedule.

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Function block execution schedule

The function block execution schedule is derived from the portion of the link schedule that deals with starting the execution of each function block or FB_START indications. The link schedule provides only those entries that pertain to the blocks residing in a given fieldbus device. While device function blocks may be synchronized to the link schedule, it is not a Foundation Fieldbus mandated feature. They may run asynchronously.

The block execution time can be broken into these three phases.

1. Preprocessing — Snap-shot of parameter values

2. Execution — Function block outputs are determined

3. Postprocessing — Block output values, alarm and associated

trend parameters are updated.

Since input parameter values used by a function block must not change during execution, a copy of the input parameter values is captured or snapped at the beginning of execution. Also, since block outputs to other blocks must be time coincident, the output values are only updated at the completion of the function block execution. The block algorithm execution phase is always executed in the following ordered sequence as shown in Figure 2.9.

1. Determine the actual mode attribute of the mode parameter.

This calculation is based on the target mode and the status attributes of input parameters.

2. Calculate the set point, if the Set Point parameter is defined for

the function block.

The calculation of working set point is based on the actual mode, set point input parameters such as cascade and remote cascade, and any backward path input status. Also, the value of the controlled parameter, process variable, may be used for set point tracking. The resulting set point is shown in the set point parameter.

3. Execute the control or calculation algorithm to determine the

value and status of output parameters in the forward path.

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The conditions that determine the status attribute of output parameters. The value attributes of the block's input parameters and contained parameters, the actual mode and the working set point are used in this algorithm. Also, where defined by the block profile, some blocks may use the status of selected inputs.

Integrating Fieldbus into Rockwell Automation Logix System 2-27

In general, the calculation of actual mode and the use of actual mode in the algorithm accounts for the status of critical inputs.

4. Calculate output parameters in the backward path.

This phase applies only to output blocks and calculation blocks designed for use in a cascade path.

Cascade

Remote Cascade

Remote Out

Target Mode

TIP

A fieldbus device whose period of function block execution is an integer factor of the macrocycle of the link will have a function block execution schedule prepared that has the optimal shorter cycle. For example, if the control strategy includes a CM with a 10 second period for a temperature loop, a second CM with a 1 second period for a pressure loop, and a third CM with a 250 millisecond period for a flow loop, a 1 second macrocycle can be downloaded to the device that contains functions blocks used in the 1 second and 250 ms CMs.

Figure 2.9 Algorithm execution phase sequence

Set Point

Calculation

Set Point PV

Mode

Calculation

Actual

Mode

Back Calculation

Primary Input

Block Specific Parameters

Out

Calculation

SP & OUT

Output

Parameters In

Backward Path

Primary Output

Remote Cascade Out Back Calculation Out Remote Out Out

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2-28 Integrating Fieldbus into Rockwell Automation Logix System

Tags, Addresses, and Live List

Tag and address assignments

Before a fieldbus device can actively join a network it must be assigned a name and data link address. Device names are system specific identifiers called physical device tags (PD_TAG).

The PD_TAGs may be assigned by the vendor or through the System Management Kernel (SMK), normally in an off-line configuration environment so devices without tags are kept off the operational network.

The SMK for devices without tags are set to the Uncommissioned state and connected to the bus at one of four default device addresses. The Data Link Layer specifies these default addresses as non-visitor node addresses. The following figure shows the general allocation of data link layer addresses to field devices.

Figure 2.10 Summary of address allocations for fieldbus devices

Non-Visitor addresses,

First Unused Node Address V(FUN)

Number of

Unused Node

Addresses

V(NUN)

used as default

addresses for devices

requiring address

assignments

Visitor addresses used for temporary (handheld) devices

Node Addresses:

Standard, Global,

010

and Flat Node

Addresses

Usable

Addresses

ATTENTION

Temporary devices such as handheld interfaces are not assigned tags or addresses. They join the network through one of four data link visitor addresses reserved for them in the data link layer

protocol.

Usable Addresses

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Integrating Fieldbus into Rockwell Automation Logix System 2-29

Live List and Uncommissioned Devices

FOUNDATION Fieldbus defines a live list as a 32-byte bitstring (256 bits) where each bit represents an address of the fieldbus network. A set bit at a particular bit number means that a device is present at that address. The LAS of the network owns the live list and maintains it as part of its operation.

The FIM constantly monitors the live list for each fieldbus link or device connected to it. When the LAS for the link recognizes a new device at a default address, it adds it to its live list according to the data link layer procedures. The FIM detects the change in the live list and makes a connection to the new uncommissioned device. It gathers the following information from the device to be passed to Control Builder.

Table 2.I Gathered information from device passed to Control Builder

Name Description Data Type Access

PdTag Physical Device Tag 32-byte string Read/Write

Address Device Address Unsigned8 Read/Write

DevID Globally unique Device

Identifier

Vendor Vendor name string 32-byte string Read Only

ModelName Model Name string 32-byte string Read Only

Rev Application Revision 32-byte string Read Only

ManufID Manufacturer Identifier Unsigned32 Read Only

DevType Device Type code Unsigned16 Read Only

DevRev Device Revision Unsigned8 Read Only

DdRev DD Revision Unsigned8 Read Only

32-byte string Read Only

Control Builder uses the device information to create an item in its Monitoring tree to represent the new uncommissioned device on the given link. Users can now view and configure pertinent information for the uncommissioned device through appropriate Link block and device block configuration forms in Control Builder.

TIP

The FIM must be configured and loaded through Control Builder before you can view the module. You can view the module’s links and devices through the Monitoring tab of Control Builder.

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Foundation Fieldbus Performance

Foundation Fieldbus, FF, is a very powerful network providing both communication and distributed control capability. However, fast response is not one of its great capabilities. The screen capture below reflects the time allocated for 18 function blocks to publish their outputs on Fieldbus. The average time is about 40 ms. per published value.

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Part of the reason that Fieldbus is slow is that Fieldbus devices operate on very small amounts of current.

• 10 to 20 ma. per device is typical.

• Translates into slow computations in the transmitters.

• Typically takes 100 ms for a fieldbus transmitter to make a new

measurement of an input with all the associated calculations completed.

• Therefore, when attempting to determine the performance of a fieldbus system, please recognize these facts.

Performance calculation considerations:

Integrating Fieldbus into Rockwell Automation Logix System 2-31

• Some pressure transmitters will read their transducers and create a new floating point digital readings of the PV every 100 ms.

• That value can only be read every 40 to 50 milliseconds because of the Fieldbus data rate, and of the Fieldbus protocol.

• The data rate is 31.25 Kbps, or 31 bits per millisecond. Very very slow by comparison with ControlNet or Ethernet.

• A minimum Fieldbus message uses 99 bits. A minimum response uses 150 bits. Just to put those messages on the wire takes 8 ms.

The protocol says that you must allow time for each device to send nonscheduled messages, in addition to the Publishing of the Precess Variables, that are scheduled. The protocol also says that you must allow significant time for a Fieldbus device to respond to a request for data or information. The result of the slow data rate and the protocol dictate that Fieldbus configuration tools allow 40 to 50 milliseconds for the transmission of data from each Function Block. Also, many pressure transmitters measures both the pressure and the temperature.

If the application dictates that both values must be used, then 80 to 100 milliseconds will be allocated to communicating with those two function blocks, in that one pressure transmitter. Both the Pressure and the Temperature interface with other Fieldbus devices through independent function blocks, so each require their own 40 to 50 milliseconds.

The CN2FF operates on the Fieldbus side at the max. speed of the Fieldbus, and at the ControlNet rate on the ControlNet side. Therefore, the CN2FF is not a limiting factor in a Fieldbus systems performance. When a CN2FF operates, the Fieldbus side and the CN side run asynchronously. When the CN2FF receives data, it is stored in the CN2FF and is Produced on CN at the NUT rate. Therefore, in a typical CN2FF Fieldbus system, the controller will be receiving a lot of redundant data.

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Notification Scheme

Fieldbus versus ProcessLogix Alarm Priorities

The Fieldbus alarms are closely integrated with the existing ProcessLogix notification system. The ProcessLogix Server handles FIM alarms in the same way it handles Control Processor ones. But, the fieldbus devices themselves own their alarm data and generate the alarms, clears, and events.

Fieldbus devices use 0 to 15 as numeric priorities for alarm reporting. ProcessLogix alarms use Journal, Low, High and Urgent as priorities with a sub-priority of 0 to 255. Table 2.J shows how fieldbus priorities are mapped to ProcessLogix priorities and severities.

Table 2.J Mapping Fieldbus Priorities to ProcessLogix

Fieldbus Alarm Priority ProcessLogix Alarm

Priority

0 (Can never be seen by FIM

or above)

1 (Can never be seen by FIM

or above)

2 BLOCK_ERR bit 14 (power-up) BLOCK_ERR bit 15 (Out-of-Service)

Journal (Event System Only)

ProcessLogix Alarm Severity

(Can never be seen by FIM or above)

3 All other bitstring indications: (BLOCK_ERR bits 0-13, XD_ERROR bits 16-25)

2 (User selected) Journal 2

3Low3

4Low4

5Low5

6Low6

7Low7

8High8

9High9

10 High 10

11 High 11

12 Urgent 12

13 Urgent 13

14 Urgent 14

15 Urgent 15

System Level Diagnostic (High)

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Fieldbus Alarm Conditions

Fieldbus devices provide both process and device related alarms. The fieldbus devices themselves own their alarm data; generates and clears the alarms and events. The process alarms are associated with process variable conditions and they are reported as process alarms into ProcessLogix.

The device alarms are associated with actual device conditions or processes within the block as indicated by BLOCK_ERR and XD_ERROR bitstring alarms. These alarms are reported as device or system alarms into the ProcessLogix notification system. Table 2.K summarizes the possible fieldbus alarm enumerations and lists the alarm/event type identification to be used in the alarm summary and event summary displays in Station.

TIP

Fieldbus alarm functions do not support rate of change (ROC) alarms. ROC alarms can only be generated in applications that use ProcessLogix data acquisition blocks for input signal conditioning.

Table 2.K Fieldbus alarm enumerations and alarm/event type identification

Enumeration Description Alarm/Event Type

UNDEF Undefended Alarm No Action

LO Low Limit Alarm PVLO

HI High Limit Alarm PVHI

LO LO Critical Low Limit Alarm PVLOLO

HI HI Critical High Limit Alarm PVHIHI

DV LO Deviation Low Alarm DEVLO

DV HI Deviation High Alarm DEVHI

DISC Standard Discrete Alarm OFFNORM

DISC Standard Discrete Alarm CHNGOFST

DISC DevCtl Fail Alarm FBDCFAIL

DISC DevCtl Accept Alarm FBDCACC

DISC DevCtl Ignore Alarm FBDCIGN

BLOCK BLOCK_ERR: 0 (Other (LSB) FFOTHER

BLOCK BLOCK_ERR: 1 (Block Configuration Error) FFBLKCFG

BLOCK BLOCK_ERR: 2 (Link Configuration Error) FFLNKCFG

BLOCK BLOCK_ERR: 3 (Simulate Active) FFSIMACT

BLOCK BLOCK_ERR: 4 (Local Override) FFLO

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Table 2.K Fieldbus alarm enumerations and alarm/event type identification

Enumeration Description Alarm/Event Type

BLOCK BLOCK_ERR: 5 (Dev Fault State Set) FFFLSAFE

BLOCK BLOCK_ERR: 6 (Dev Needs Maintenance Soon) FFDEVNMS

BLOCK BLOCK_ERR: 7 (I/P Failure or PV BAD Status) FFINFL

BLOCK BLOCK_ERR: 8 (O/P Failure) FFOUTFL

BLOCK BLOCK_ERR: 9 (Memory Failure) FFMEMFL

BLOCK BLOCK_ERR: 10 (Lost Static Data) FFLSTDTA

BLOCK BLOCK_ERR: 11 (Lost NV Data) FFLNVDTA

BLOCK BLOCK_ERR: 12 (Readback Check Failed) FFRBCKFL

BLOCK BLOCK_ERR: 13 (Dev Needs Maintenance Soon) FFDEVNMS

BLOCK BLOCK_ERR: 14 (Power Up) FFPWRUP

BLOCK BLOCK_ERR: 15 (Out-Of-Service) FFOOS

BLOCK XD_ERROR: 16 (Unspecified Error) TBUNSPEC

BLOCK XD_ERROR: 17 (General Error) TBGENRAL

BLOCK XD_ERROR: 18 (Calibration Error) TBCALERR

BLOCK XD_ERROR: 19 (Configuration Error) TBCFGERR

BLOCK XD_ERROR: 20 (Electronics Failure) TBELECFL

BLOCK XD_ERROR: 21 (Mechanical Failure) TBMECHFL

BLOCK XD_ERROR: 22 (I/O Failure) TBIOFL

BLOCK XD_ERROR: 23 (Data Integrity Error) TBDTAERR

BLOCK XD_ERROR: 24 (Software Error) TBSWERR

BLOCK XD_ERROR: 25 (Algorithm Error) TBALGERR

UPDATE TB Static Data Update Event TBSTCHNG

UPDATE FB Static Data Update Event FBSTCHNG

WRITE Write Protect Change Alarm RBWPCHNG

UPDATE Link Object Update Event FBLOCHNG

UPDATE Trend Object Update Event No Action

ATTENTION

When using the 1788-CN2FF, no alarms come from Fieldbus devices when used with ProcessLogix. Data with status will be produced.

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Alert Object Formal Model

The alert object allows block alarms and events to be reported to a device responsible for alarm management.

Class: Alert Subclass of: Root Attributes:

1. (m) (r) DD Member Id

2. 2. (m) (Key) Index

3. 3. (m) (r) Data Type

3.1 (m) (r) Meta Type = RECORD

3.2 (m) (r) Type Name = Alert

4. (m) (r) Sub-index

4.1 (m) (r) Block Index - Unsigned16

4.2 (m) (r) Alert Key - Unsigned8

4.3 (m) (r) Standard Type - Unsigned8

4.4 (m) (r) Mfr Type - Unsigned8

4.5 (m) (r) Message Type - Unsigned8

4.6 (m) (r) Priority - Unsigned8

4.7 (m) (r) Time Stamp - Time Value

5. (m) (r) Data Length

6. (m) (r) Units = “ “

7. (m) (r) Usage = CONTAINED

8. (m) (r) Storage = DYNAMIC

9. (m) (r) List of Valid Values

Standard type enumerations 0-12 are defined. Message type enumeration’s 0-3 are defined - see attribute definitions.

10. (m) (r) Initial Value

11. (m) (r) DD Item Id

Services:

1. (m) FB_Alert_Notify

2. (m) FB_Alert_Ack

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Table 2.L Attribute Definitions

Attribute Definition

DD Member Id A unique number which identifies the alert. This number will be

Index The location of the alert in the OD.

Meta Type Identifies the alert as a record (multiple values of different types).

Type Name Identifies the data format as a data structure associated with the Meta

Sub-index Attributes of an object which may be individually accessed through the

Data Length The number of bytes required to represent the data type.

assigned as part of the development of the Device Description (DD). A DD member Id is assigned if an object is defined as part of a structure. A value of zero (0000) will be used for the DD member Id if the object is not part of a structure.

type.

FB_Read and FB_Write service by using the sub-index number with the object index number. Sub-index numbers are assigned based on Meta type.

Units The engineering units in which the value is represented.

Usage Indication of whether the alert may be linked to a block parameter.

Storage Specification that alert must be stored in dynamic (D) memory.

List of Valid Values

Standard type will have the following enumerated values.

Table 2.M Standard type valid values

Valid Values Meaning

0 Undefined

1 LO - Low limit

2 HI - High limit

3 LO LO - Critical low limit

4 HI HI - Critical high limit

5 DV LO - Deviation low

6 DV HI - Deviation high

7 DISC - Discrete

8 BLOCK - Block Alarm

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9 UPDATE - Static data update

10 WRITE - Write protect changed

Integrating Fieldbus into Rockwell Automation Logix System 2-37

Table 2.M Standard type valid values

Valid Values Meaning

11 UPDATE - Link associated with function block

12 UPDATE - Trend associated with block

Message type will be enumerated in the following manner: 0 = 1 = Event Notification 2 = Alarm Clear 3 = Alarm Occur

The alert object contains information from an alarm or update event object, which is to be sent in the notification message. The alert object will be invoked by the alert notification task. If multiple alarms or event parameters are unreported, then the one with the highest priority or is the oldest of equal priority will be selected by the alert notification task.

The selected alert object is sent in a message at the first opportunity less than the alert confirm time. If a confirmation from an interface device is not received by the alarm notification routine in the field device within a time determined by the resource block confirm time parameter, then the alert will be considered unreported so it may be considered for selection.

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1757-FIM Planning Considerations

Chapter

Reference Publications

Please refer to the following Rockwell Automation publications for general planning details and installation considerations for the ProcessLogix system in general.

Table 3.A Publication References

Publication Name Publication Number

ProcessLogix R400.0 Installation and Upgrade Guide 1757-IN040B-EN-P

ProcessLogix R400.0 Selection Guide 1757-SG001B-EN-P

1757-FIM Installation Instructions 1757-IN913A-EN-P

1757-RPT Installation Instructions 1757-IN915A-EN-P

1788-CN2FF Installation Instructions 1757-IN051B-EN-P

NI-FBUS Configurator User Manual 1788-6.5.2

1757-PLX52 ProcessLogix Controller Module Installation Instructions

Other Manuals Available

ProcessLogix Theory Manual 1757-RM805A-EN-P

ProcessLogix Function Block Reference 1757-RM810A-EN-P

ProcessLogix Error Codes and Troubleshooting 1757-TG001A-EN-P

1757-IN901C-EN-P

ProcessLogix Function Block Parameters 1757-RM811A-EN-P

If this is a new ProcessLogix system installation, we recommend that you familiarize yourself with the contents of these publications before you install any ProcessLogix system equipment. Visit us at: http:\\www.theautomationbookstore.com or contact your local sales office to obtain these manuals.

1 Publication 1757-UM006A-EN-P - May 2002

3-2 1757-FIM Planning Considerations

Installation declaration

ATTENTION

Environment and Enclosure

This equipment is intended for use in a Pollution Degree 2 industrial environment, in overvoltage Category II applications (as defined in IEC publication 60664-1), at altitudes up to 2000 meters without derating.

This equipment is considered Group 1, Class A industrial equipment according to IEC/CISPR Publication 11. Without appropriate precautions, there may be potential difficulties ensuring electromagnetic compatibility in other environments due to conducted as well as radiated disturbance.

This equipment is supplied as “open type” equipment. It must be mounted within an enclosure that is suitably designed for those specific environmental conditions that will be present and appropriately designed to prevent personal injury resulting from accessibility to live parts. The interior of the enclosure must be accessible only by the use of a tool. Subsequent sections of this publication may contain additional information regarding specific enclosure type ratings that are required to comply with certain product safety certifications.

See NEMA Standards publication 250 and IEC publication 60529, as applicable, for explanations of the degrees of protection provided by different types of enclosure. Also, see the appropriate sections in this publication, as well as the Allen-Bradley publication 1770-4.1 (“Industrial Automation Wiring and Grounding Guidelines”), for additional installation requirements pertaining to this equipment.

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1757-FIM Planning Considerations 3-3

FIM and I/O module allowance

Be sure your ProcessLogix System Fieldbus and I/O requirements do not exceed the capacities listed in the following table. In terms of processing allocations, the FIM is the equivalent of three I/O modules.

Table 3.B

Component Total Per Controller Total Per Server

Maximum number of FIMs plus I/O modules divided by three (including local and remote chassis I/O and rail I/O).

Maximum number of H1 links (independent LAS)

Maximum number of fieldbus devices

(1)

Each H1 link is capable of supporting (a practical limit) at least 16 fieldbus devices. This number may vary depending on the dynamics of the link.

(1)

21 100

42 200

672 3,000

Fieldbus network references

Please refer to the following publications for guidance in designing and implementing the fieldbus network to be interfaced to the ProcessLogix system through the FIM and its companion Remote Termination Panel (RTP).

Table 3.C

Publication Number/Title Scope Source

AG-140 / Wiring and Installation 31.25 kbit/s, Voltage Mode, Wire Medium Application Guide

AG-165 / Fieldbus Installation and Planning Guide

Relcom Inc. Provides fieldbus wiring

Overview of what you need to know to wire, power, and layout network components

Outlines things to consider before installing a fieldbus network

products, wiring design and installation data. Offer a free Fieldbus Wiring Design and Installation Guide you can download.

Publication 1757-UM006A-EN-P - May 2002

Fieldbus Foundation 9390 Research Blvd. Suite II-250 Austin Texas 78759-9780

www.fieldbus.org

Fieldbus Foundation 9390 Research Blvd. Suite II-250 Austin Texas 78759-9780

www.fieldbus.org

Visit the Relcom Inc. website

www.relcominc.com

3-4 1757-FIM Planning Considerations

Fieldbus wiring selection and calculation

The preferred cable for connecting fieldbus devices is #18 AWG (0.8mm

the planned topology for your fieldbus segment, selected wiring, supplied power and intended mix of fieldbus devices may impact the overall performance of a fieldbus network.

The original Fieldbus specification allows using twisted pair wiring, which is commonly used for 4-20 ma transmitters.

) shielded, twisted pair wire. It is important to calculate how

Installing 1757-FIM Fieldbus Interface Module

TIP

Windows based, Fieldbus Segment Calculator tools are available in the market place that can assist you in calculating the performance characteristics of a planned fieldbus segment.

See Appendix D for a condensed overview of fieldbus wiring considerations provided for convenient reference. This information does overlap some information that is found in other data references as well.

Refer to the 1757-FIM Installation Instructions, publication 1757-IN0913A-EN-P.

We ca n’t emphasize enough the use of high quality network (wire) installation. The higher quality of installation materials the better performance you will achieve in your network application

Universal manufacturers sell “Fieldbus cable” which meets all the specifications required for “Fieldbus cable”.

Installing 1757-RTP Remote Terminator

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Refer to the 1757-RTP Installation Instructions, publication 1757-IN915A-EN-P.

Before You Start

Question: If your answer is: If your answer is

Configurating the 1757-FIM

Table 4.A Where do you begin?

Chapter

What do you know about Control Builder?

Do you know how to configure a Control Processor Module?

Can you configure a Control Module?

Are you familiar with your system architecture?

Are you ready? Once you have addressed all the questions in this section, you are ready to move on to the next

Nothing. Read the Functional Overview section in the Control Building Guide or locate the topic in Knowledge Builder. This section shows you how to launch the application and complete the Server login.

No. Read the Creating a Control Processor Module section in the Control Building Guide or find the topic in Knowledge Builder. This section shows you how to create a Control Processor Module (CPM) and its associated Control Execution Environment (CEE).

No. Read at least the Creating and Saving a Control Module section in Knowledge Builder. This section shows you how to create a Control Module (CM) and insert and connect function blocks.

To complete the configuration data for certain components, you must know the planned or current location of the associated hardware components in your ProcessLogix system architecture. This includes the chassis slot location for any given CPM and FIM. We suggest that you create a simple diagram that outlines the location of components in your system showing slot locations and communication addresses for reference during configuration.

section Configuring Fieldbus Components. At this point, you should have at least a working knowledge of the Control Builder application.

Yes, you can skip this section.

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4-2 Configurating the 1757-FIM

Figure 4.1 Example Rockwell Fieldbus Configuration

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Configurating the 1757-FIM 4-3

Configuring Fieldbus Components In a Control Strategy

About ProcessLogix control strategy configuration

You use ProcessLogix's Control Builder application to configure a process Control Strategy using predefined function blocks. Since Fieldbus Foundation had been functionally integrated with the ProcessLogix system, the Control Builder enables the inclusion of fieldbus related Function Blocks for easy integration of fieldbus functions within the overall Control Strategy.

ProcessLogix R400.0 Control Builder includes a separate utility called the Fieldbus Library Manager application. The Fieldbus Library Manager provides the capability to create templates for fieldbus devices based on the vendor supplied Device Description (DD). This means each fieldbus device has an associated template for viewing and defining the configurable attributes of its fieldbus function blocks. These attributes include naming and identifying the component's location within the network as well as setting device and channel specific parameters, as applicable.

ATTENTION

The following information is only intended as a supplement to the Control Building Guide and does not repeat the basic functionality details for calling up, navigating, and interacting with the application.

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4-4 Configurating the 1757-FIM

Example Application and Control Strategy for Procedural Reference

Figure 4.2 shows a process feed and recycle line application being controlled through a ProcessLogix control strategy loaded in a Control Process Module (CPM) and associated Control Execution Environment (CEE). This sample application and control strategy will be used for reference to illustrate the applicability of functions in the following procedures

Figure 4.2 Sample Application and Control Strategy Integrating Fieldbus Devices with a ProcessLogix System as the Supervisory Control.

CPM/ CEE

ST3000FF

Smart Pressure

Tra nsmitter

CPM/CEE

CM102

Interlocks

FTRIG

Surge Tank

2000 Gallons

HI=70% LO=25%

DEVCTL

FIM

T-106

SP = 50%

HIHI=85% LOLO=15%

IOM

Feedback

Recycle

Feed

100

gal/min

Nominal

Recycle Pump

Shut Off at LOLO Restart at 35%

IOM

Command

Logix 1400

alve Positioner

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Configurating the 1757-FIM 4-5

The application involves controlling the level of a 2000 gallon surge tank with a steady-state 100 gallon per minute (gal/min) process feed and recycle line. A fieldbus approved smart pressure transmitter is being used to monitor the level in the surge tank. A fieldbus approved valve positioner is being used to regulate the control valve in the process feed line.

The following are some pertinent characteristics about this application and the corresponding ProcessLogix control strategy for reference.

• The goal is to recycle the process fluid back to the process with a minimum swing in the recycle feed rate.

• The tank level set point (SP) is 50 percent.

• The tank level low (LO) alarm is 25 percent and the low-low

(LOLO) alarm is 15 percent.

• The tank level high (HI) alarm is 70 percent and the high-high (HIHI) alarm is 85 percent.

• The ProcessLogix control strategy includes a tank level Control Module (CM) named CM101 and a pump control CM named CM102.

• The CM101 includes a ProcessLogix Proportional, Integral, Derivative (PID) function block configured to operate as a Proportional and Integral (PI) two-mode controller.

• The tuning for the PI controller is “loose” to allow some swing in the level of fluid in the tank.

• The CM101 includes a ProcessLogix Data Acquisition (DATAACQ) function block to provide the alarm flags for the LO, LOLO, HI, and HIHI tank level alarms.

• The CM101 includes a fieldbus Analog Input (AI) function block to integrate the tank level indicating signal from the ST3000FF smart pressure transmitter with the control strategy. It includes a fieldbus Analog Output (AO) function block to integrate the Logics 1400 Valve Positioner with the PI controller output from the control strategy.

• The CM102 includes a ProcessLogix Device Control (DEVCTL) function block to control the recycle pump through corresponding Discrete Input and Discrete Output Input/Output Module function blocks. It also includes links to the LO and LOLO alarm flags for the DATAACQ block in CM101 for device safety override and output override interlocks, respectively.

• The recycle pump is to be restarted at 35 percent.

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4-6 Configurating the 1757-FIM

System Management Timers

T1, T2, and T3 are the System Management Timers. The units are 1/32000 of a second, so 96000 gets 3 seconds.

T1 specifies how long the 1788-CN2FF waits for an answer to a System Management message, such as Set PD Tag.

The time needs to include the time to acquire the Token for Unscheduled Transmission, transmit the message, remote node to process the message, remote node to acquire Token, transmit reply. Depending on the Function Block execution and Publishing schedule, this might take as little as 100 mS, but 3 seconds is recommended by the FF, and it doesn't hurt to allow extra time for slow nodes or slow commands.

T2 specifies how long a Remote Node, such as a Pressure Transmitter waits for the next System Management message in a series of System Management messages until it concludes that the System Manager has failed. This is used for SET_ADDRESS sequence as shown in the following diagram.

As you can see, to set a node's address requires several messages to be sent from the System Manager (the CN2FF in our case) to a node. If the System Manager fails before completing all the steps, the Remote Node must give up and resume operation at its previous settings. The time for the remote node to wait after each step is called T2.

Specifies how long after a node is changed to a new address it might take for it to begin communication at the new address.

This time includes stuff like writing the new information to flash memory and re-initializing some stuff, but is primarily the time it takes for the Link Active Scheduler (LAS), the CN2FF in this case, to Probe the Node at its new address.

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Configurating the 1757-FIM 4-7

Since the CN2FF only occasionally polls the addresses that have shown no previous activity (called the Slow Poll List), it takes relatively longer to detect a node at a new address than to pass the Token to a known node at an active address. The sequence is sort of like:

Pass Token 17 Pass Token 18 Pass Token 19 Pass Token 20 Probe Node 32 <no answer> Pass Token 17 Pass Token 18 Pass Token 19 Pass Token 20 Probe Node 33 <no answer> etc. up to Probe Node 255 <no answer> Pass Token 17 Pass Token 18 Pass Token 19 Pass Token 20 Probe Node 21 <answer from our new Node 21> Pass Token 17 Pass Token 18 Pass Token 19 Pass Token 20 Pass Token 21 (this one is in the Live List now) Probe Node 22 etc.

You can see that the token is passed around the ring perhaps 200 times between Probes of inactive addresses to see if there is someone new.

Software Example:

Forever:

For each address not in the Live List

For each node in the Live List

Pass Token <node transmits if it has something to say>

<node returns token> end For Probe Address to see if a Node is there now. if Node answers, add to Live List

end For

End Forever

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4-8 Configurating the 1757-FIM

ACSYNCINTR

This is the period of time between Application Clock synchronization messages. Application Clock synch messages are used to coordinate the 'application clock' among the various nodes. The Application Clock is used by each Node to begin execution of its Function Blocks at the Scheduled Time.

This is important so that the Function Block will be Done Executing at the time it is Scheduled to Publish the answers (outputs) of the Function Block to other nodes on the Fieldbus. On H1, the LAS will tell the node (through a Compel Data message) when to Publish, but it is up to the node to schedule block execution at the right time.

If the crystals of the clocks of all the Fieldbus Nodes were exactly the same, this message would not be necessary, but since a man with 2 watches never knows what time it is, the time must be re-synchronized.

The clock synchronization method facilitates synchronization of clocks which run at different speeds very well. It does not do so well for clocks that speed up and slow down. i.e. consistently slow clocks work ok, but sporadically slow clocks are difficult.

So the question is how long does it take until the clocks drift far enough apart for anyone to care?

If it is set to 1 ms, then you waste all your fieldbus messages updating the clock and never get anything done. If it is set to say 5 hours, then a clock can drift a long way from the LAS's clock causing “Stale Data” because the function block did not execute prior to the node being Compelled to Publish its data (there are other causes of Stale Data also).

5 seconds is a comprimise - reigning in deviant clocks before they get too far out of hand, yet not wasting much network bandwidth. You might increase it if you are in a real pinch for network speed, but there won’t be a measurable improvement (by removing 1 ms of traffic out of 5 seconds or 1/5000).

You can decrease it if you think that the clocks are drifting apart prior to 5 seconds, but most of the cause of clock drift is because of the jitter in delivery of time sync messages (theory, don't repeat it), so if anything, spreading the transmission error out over a longer time would help the synchronization.

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Configurating the 1757-FIM 4-9

Adding Fieldbus Interface Module to Project

Use the following procedure to add a Fieldbus Interface Module block to the Project tab in Control Builder. This also adds two Link blocks for the two H1 fieldbus links that can be associated with this FIM.

TIP

You can configure a FIM block in the Control Builder Project tab without the FIM hardware installed. However, it is good idea to have the communications driver and hardware that is going to be used for the system installed and configured. The FIM needs the name of the communications driver specified on its configuration form to complete its configuration data. Like the CPM, the FIM represents a hardware module and the block configuration specifies the communication path to the hardware.

3. With Control Builder running, click New

⇒

FIM - Fieldbus Interface Module.

⇒ Interface Modules

The FIM Block Parameters window opens.

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4-10 Configurating the 1757-FIM

4. Leave the CB assigned Name FIMxx, where xx equals the next

unique sequential number. Or, enter a unique name of up to 16 characters.

5. In the Network field, select the communications medium your

ProcessLogix system uses. Ethernet or ControlNet, ControlNet is the default selection.

6. In the Driver Name field, select the correct communications

driver.

TIP

The communications driver must be installed and configured for it to be included in the dropdown list.

7. If the FIM is located in a remote chassis, go to step 9.

In the Supervisory Chassis MAC field, select the MAC address assigned to the ControlNet Network module connected to the Supervisory network also known as the “uplink”.

8. In the Supervisory Chassis Slot Number field, select the slot

number where the FIM is installed. Go to step 12.

9. If the FIM is located in a remote chassis, select the check box

next to the Remote Chassis Field.

10. In the Remote MAC Address field, select the address of the

ControlNet Network module in the Remote I/O Chassis.

11. In the Remote Chassis Slot Number field, select the slot number

where the FIM is installed.

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Configurating the 1757-FIM 4-11

12. Leave all other fields on the Main tab at their defaults, as these

are the only valid values at this point.

Click the Statistics tab.

Data is only present in these fields when the FIM/LINK is loaded and communicating with the system.

13. Click the Server Parameters Tab.

14. Leave the Point Detail Page and Control Level fields at their

default.

The Associated Display and Group Detail Page are not required to complete the configuration, but can be entered if known.

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4-12 Configurating the 1757-FIM

15. Click OK.

The FIM icon is added to the Project tab. The FIM also includes icons for the two H1 fieldbus links that it supports.

TIP

Refer to the 1757-FIM as a controller because the module can function independently, without a 1757-PLX52.

Checking link configuration

Use the following steps to check the link configuration of the links associated with a given FIM block. This procedure assumes that you have configured a FIM block in the Project tab of Control Builder.

TIP

You can configure a Link through the Project tab of Control Builder without having the link installed. However, some parameters on the Link configuration form can only be viewed through the Monitoring tab with the FIM and Link installed and communicating with the system.

Be sure to click the plus sign in front of the FIM icon to open its directory tree and expose the link icons.

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1. Double-click the link icon .

The Link Block Parameters window opens.

Configurating the 1757-FIM 4-13

2. Leave the CB assigned name LINKxx, where xx equals the next

unique sequential number assignment. Or, enter a unique number of up to 16 characters.

3. In the Description field, enter a description of up to 24

characters. This text appears in applicable detail and group displays associated with this block.

The other parameters can not be configured because they are only active in the Monitoring tab after the FIM/LINK is loaded and communicating with the system.

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4-14 Configurating the 1757-FIM

4. Click the System Management tab.

ATTENTION

Do not change the default value settings for the active parameters in this window unless you are familiar with tuning the performance of fieldbus links.

5. In the Step Time Preset (T1) field, either leave the default value

of 96000, or enter a new value.

This is the preset value for the System Management step timer in 1/32 millisecond increments.

6. In the Preset Set Addr Seq Timer (T2) field, either leave the

default value of 1920000, or enter a new value.

This is the preset value for the System Management set address sequence timer in 1/32 millisecond increments.

7. In the Preset Set Addr Seq Timer (T3) field, either leave the

default value of 480000, or enter a new value.

This is the preset value for the System Management set address wait timer in 1/32 millisecond increments.

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Rockwell Automation PLC-5 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Important User Information

Preface

Contents guide

Conventions

Rockwell Automation Technical Support

Local Product Support

Obtain Technical Product Support

Your Questions or Comments about This Manual

Table of Contents

Fieldbus Organization

About the Fieldbus Foundation

Want more information?

What is Fieldbus?

Open Communications Architecture

Communication Layer Description

Standard Function Blocks

About Modes of Operation

Analog Input Block

Analog Output Block

Bias/Gain Block

Control Selector Block

Discrete Input Block

Discrete Output Block

Manual Loader Block

Proportional/Derivative Block

Proportional/Integral/Derivative Block

Ratio Block

Device Descriptions and Block Parameters

About Device Descriptions

Device Description Language

Device Description infrastructure

Foundation Fieldbus Performance

Performance Calculation Considerations

Overview

Background - the goals of integration

Fieldbus Integrated Architecture

Fieldbus Interface Modules - The Key to an Integrated System

Configuration Tools

1788-CN2FF Linking Device

ControlBuilder

Foundation Fieldbus Configuration Tool

Centralized Operator Interface

Network Management description

System Management Description

About the Device Object

About the VFD Object

Fieldbus Device Analog Input Integration

Fieldbus Analog Input data manipulation

Fieldbus device Analog Output or PID integration

Fieldbus Analog Output or PID data manipulation

Fieldbus device Discrete Input integration

Fieldbus Discrete Input data manipulation

Fieldbus device Discrete Output data integration

Fieldbus Discrete Output data manipulation

Interface Connections Summary

Fieldbus status data details

Fieldbus Status Indications

Control Mode Interaction

Fieldbus Block Modes Versus Processlogix Modes

Control Mode Priorities and Indications

Rotary Switch Model versus Toggle Switch Model

Display indications and mode calculation

Link and Block Schedules

Link Active Scheduler (LAS)

Link Schedule

Function block execution schedule

Tags, Addresses, and Live List

Tag and address assignments

Live List and Uncommissioned Devices

Foundation Fieldbus Performance

Notification Scheme

Fieldbus versus ProcessLogix Alarm Priorities

Fieldbus Alarm Conditions

Alert Object Formal Model

List of Valid Values

Reference Publications