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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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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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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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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