Emerson 848L Users Manual Logic Transmitter With FOUNDATION Fieldbus

2015-01-05

: Emerson Emerson-848L-Users-Manual-165686 emerson-848l-users-manual-165686 emerson pdf

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Rosemount 848L Logic Transmitterwith FOUNDATION™ Fieldbus
Table of Contents
Section 1 Introduction
Section 2 Installation
Section 3 Configuration
Section 4 Operation and Maintenance
Appendix A Reference Data
Appendix B Product Certifications
Appendix C Function Blocks
Appendix D Logic Equation Syntax
Appendix E Motor Control
Appendix F Valve Control
Index

www.rosemount.com

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L Logic Transmitter

with FOUNDATION™ Fieldbus

Product Discontinued

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Rosemount 848L Discrete Logic

Temperature Transmitter with

FOUNDATION Fieldbus

Cover photo: 848-848C004

NOTICE

Read this manual before working with the product. For personal and system safety, and for

optimum product performance, make sure to thoroughly understand the contents before

installing, using, or maintaining this product.

The United States has two toll-free assistance numbers and one international number.

Customer Central

1-800-999-9307 (7:00 a.m. to 7:00 P.M. CST)

National Response Center

1-800-654-7768 (24 hours a day)

Equipment service needs

International

1-(952) 906-8888

The products described in this document are NOT designed for nuclear-qualified

applications.

Using non-nuclear qualified products in applications that require nuclear-qualified hardware

or products may cause inaccurate readings.

For information on Rosemount nuclear-qualified products, contact a Emerson Process

Management Sales Representative.

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Table of Contents

SECTION 1

Introduction

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

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

Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Return of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

SECTION 2

Installation

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Mounting to a DIN Rail Without an Enclosure. . . . . . . . . . . . . . . . . . . . . 2-2

Mounting to a Panel with a Junction Box . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Mounting to a 2-Inch Pipe Stand. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Power Supply Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Surges/Transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

I/O Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Transmitter Label. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Using Cable Glands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Using Conduit Entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

SECTION 3

Configuration

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

General Block Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Link Active Scheduler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Block Instantiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

Resource Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

FEATURES and FEATURES_SEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

MAX_NOTIFY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

PlantWeb™ Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

I/O Transducer Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Logic Transducer Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Discrete Input Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20

Discrete Output Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21

Multiple Discrete Input Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21

Multiple Discrete Output Block. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L

TOC-2

SECTION 4

Operation and

Maintenance

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Foundation Fieldbus Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Commissioning (Addressing) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Hardware Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Sensor Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Communication/Power Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Resetting the Configuration (RESTART) . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Foundation Fieldbus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Resource Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

I/O Transducer and Logic Block Troubleshooting . . . . . . . . . . . . . . . . . . 4-3

NAMUR Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

APPENDIX A

Reference Data

Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-1

Functional Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-1

Physical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-4

Function Blocks Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-4

Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-5

Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-7

APPENDIX B

Product Certifications

Approved Manufacturing Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-1

European Directive Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-1

Hazardous Locations Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-1

North American Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-1

European Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-2

APPENDIX C

Function Blocks

Resource Block Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-1

I/O Transducer Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-5

Logic Transducer Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-8

Discrete Input Block. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-9

Discrete Output Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-11

Supported Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-11

Multiple Discrete Input Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-12

Multiple Discrete Output Block. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-13

Reference Manual

00809-0100-4696, Rev AA

September 2004

TOC-3

Rosemount 848L

APPENDIX D

Logic Equation Syntax

Error Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-4

Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-5

APPENDIX E

Motor Control

Introduction to Motor Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-1

Variations on Motor Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-2

Writing 848L Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-4

Basic Motor Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-4

Interlock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-5

Permissive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-5

Emergency Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-5

Restart Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-6

Maximum Restarts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-7

Winding Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-8

Hand-Off-Auto . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-9

Intermediate Stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-10

Redundant Motors - Alternate Start . . . . . . . . . . . . . . . . . . . . . . . . . . .E-11

Redundant Motors - Timed Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-12

Redundant Motors - Switch on Failure . . . . . . . . . . . . . . . . . . . . . . . . .E-14

APPENDIX F

Valve Control

Introduction to Valve Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-1

Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-2

Variations on Valve Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-2

Boolean Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-3

Basic Valve Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-3

Open-Auto-Close . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-4

Alarm Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-4

Output Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-4

Output with Interlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-4

Simple Valve Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-5

Permissive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-5

Double Block and Bleed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-6

Motorized Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-7

Heat Exchange Medium Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-7

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L

TOC-4

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Section 1 Introduction

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-1

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

Return of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1-3

SAFETY MESSAGES Instructions and procedures in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that

potentially raises safety issues is indicated by a warning symbol ( ). Please

refer to the following safety messages before performing an operation

preceded by this symbol.

Warnings

Failure to follow these installation guidelines could result in death or

serious injury.

• Make sure only qualified personnel perform the installation.

Electrical shock could cause death or serious injury.

• If the device or senors are installed in a high voltage environment and a fault

condition or installation error occurs, high voltage may be present on transmitter

leads and terminals.

• Use extreme caution when making contact with the leads and terminals.

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L

1-2

OVERVIEW

Transmitter The 848L provides a cost effective field mounted interface for discrete inputs

and outputs on a Foundation Fieldbus H1 network. The 848L allows you to

leverage the fieldbus network to reduce discrete input and output wiring and

eliminate the need for a separate bus for discrete inputs and outputs. The

848L can communicate with other devices on the segment to provide logic

interactions independent of any upper level controller.

The 848L also has logic capability allowing it to independently control outputs

based on the state of one or more of it's inputs or discrete signals from other

devices on the network. A Logic Block allows for up to 20 Boolean equations,

8 Inputs, and 4 Outputs.

Manual This manual is designed to assist in the installation, operation, and

maintenance of the Rosemount 848L Logic Transmitter.

Section 1: Introduction

• Overview

• Considerations

• Return of Materials

Section 2: Installation

• Mounting

• Installation

• Wiring

• Power Supply

• Commissioning

Section 3: Configuration

•F

OUNDATION fieldbus Technology

• Configuration

• Function Block Configuration

Section 4: Operation and Maintenance

• Hardware Maintenance

• Troubleshooting

Reference Manual

00809-0100-4696, Rev AA

September 2004

1-3

Rosemount 848L

Appendix A: Specification and Reference Data

• Specifications

• Dimensional Drawings

• Ordering Information

Appendix B: Product Certificates

• Hazardous Locations Certificates

• Intrinsically Safe and Non-Incendive Installations

• Installation Drawings

Appendix C: Function Blocks

• Device Descriptions

• Block Operation

Appendix D: Logic Equation Syntax

• Error Handling

• Examples

Appendix E: Motor Control

• Variations of Motor Control

• Writing 848L Equations

Appendix F: Valve Control

RETURN OF MATERIALS To expedite the return process in North America, call the Emerson Process

Management National Response Center toll-free at 800-654-7768. This

center, available 24 hours a day, will assist with any needed information or

materials.

The center will ask for the following information:

• Product model

• Serial numbers

• The last process material to which the product was exposed

The center will provide

• A Return Material Authorization (RMA) number

• Instructions and procedures that are necessary to return goods that

were exposed to hazardous substances

For other locations, please contact an Emerson Process Management sales

representative.

NOTE

If a hazardous substance is identified, a Material Safety Data Sheet (MSDS),

required by law to be available to people exposed to specific hazardous

substances, must be included with the returned materials.

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L

1-4

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Section 2 Installation

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1

Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1

Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-4

Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-5

Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-5

I/O Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-7

Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-8

Transmitter Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-9

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-9

SAFETY MESSAGES Instructions and procedures in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that

potentially raises safety issues is indicated by a warning symbol ( ). Please

refer to the following safety messages before performing an operation

preceded by this symbol.

Warnings

MOUNTING The 848L is always mounted remote from the sensors and output devices.

There are three mounting configurations:

• To a DIN rail without an enclosure

• To a panel with an enclosure

• To a 2-in pipe stand with an enclosure using a pipe mounting kit

Failure to follow these installation guidelines could result in death or

serious injury.

• Make sure only qualified personnel perform the installation.

Electrical shock could cause death or serious injury.

• If the device or sensors are installed in a high voltage environment and a fault

condition or installation error occurs, high voltage may be present on transmitter

leads and terminals.

• Use extreme caution when making contact with the leads and terminals.

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount 848L

2-2

Mounting to a DIN Rail

Without an Enclosure

To mount the 848L to a DIN rail without an enclosure, follow these steps:

1. Pull up the DIN rail mounting clip located on the top back side of the

transmitter.

2. Hinge the DIN rail into the slots on the bottom of the transmitter.

3. Tilt the 848L and place onto the DIN rail. Release the mounting clip.

The transmitter should be securely fastened to the DIN rail.

Figure 2-1. Mounting the 848L to

a DIN Rail

Mounting to a Panel with

a Junction Box

When inside of a plastic or aluminum junction box, the 848L mounts to a panel

using four 1/4-20 x 1.25-in. screws.

When inside of a stainless steel junction box, the 848L mounts to a panel

using two 1/4-20 x 1/2-in. screws.

Figure 2-2. Mounting the 848L

junction box to a panel

DIN Rail Mounting Clip

848L without

enclosure

DIN Rail

Aluminum/Plastic Stainless Steel

848L with aluminum or plastic box

Panel

Mounting

Screws (4)

Cover

Screws (4) 848L with a stainless steel box

Panel

Mounting

Screws (2)

Reference Manual

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September 2004

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Rosemount 848L

Mounting to a 2-Inch

Pipe Stand

Use the optional mounting bracket (option code B6) to mount the 848L to a

2-inch pipe stand when using a junction box.

Aluminum/Plastic Junction Box

(styles JA and JP)

Stainless Steel Junction Box

(style JS)

Front View Side View Front View Side View

Dimensions are in inches (millimeters)

Aluminum/Plastic Junction Box

Mounted on a Vertical Pipe

Stainless Steel Junction Box

Mounted on a Vertical Pipe

5.1

(130)

10.2

(260)

6.6 (167)

fully

assembled

4.5

(114)

848_848A52A, B, 53A, B

7.5 (190)

fully

assembled

848_848A54A, 55A

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September 2004

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2-4

WIRING If the device or sensors are installed in a high-voltage environment and a fault

condition or installation error occurs, the sensor leads and transmitter

terminals could carry lethal voltages. Use extreme caution when making

contact with the leads and terminals.

NOTE

Do not apply high voltage (e.g. AC line voltage) to the transmitter bus or I/O

power terminals. Abnormally high voltage can damage the unit (bus and I/O

power terminals are rated to 42.4 VDC).

Figure 2-3. 848L Transmitter

Fieldbus Wiring

Power Supply

Connections

The transmitter requires both a fieldbus connection and power for the discrete

I/O channels.

Fieldbus Connection

The fieldbus connection requires between 9 and 32VDC to operate the

electronics. The dc power supply should provide power with less than 2%

ripple. A fieldbus segment requires a power conditioner to isolate the power

supply filter and decouple the segment from other segments attached to the

same power supply. Signal wiring should be shielded, twisted pair for best

results in electrically noisy environments. Do not use unshielded signal wiring

in open trays with power wiring or near heavy electrical equipment. Use

ordinary copper wire of sufficient size to ensure that the voltage across the

bus terminals does not go below 9 VDC. The power terminals are not polarity

sensitive. To power the electronics and establish communications:

1. Connect the fieldbus wires to the terminals marked "Bus" as shown in

Figure 2-4 on page 2-5.

2. Tighten the terminal screws to ensure adequate contact.

Power

Supply

Terminators

Devices 1 through 16*

Integrated Power

Conditioner

and Filter

(Spur)

Signal

Wiring

FOUNDATION

fieldbus Host or

configuration tool

6234 ft (1900 m) max

(depending upon cable

characteristics)

848-848_01A

(Trunk)

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September 2004

2-5

Rosemount 848L

Figure 2-4. “Bus” location on the

Rosemount 848L

Input/Output Power:

The discrete I/O requires a 9-32VDC power supply that is separate from the

fieldbus power. The voltage level will depend on the type of sensors being

used and outputs being driven. To power the I/O:

1. Connect the positive lead from the power supply to the (+) terminal

marked "PWR".

2. Connect the return lead to the (-) terminal marked "PWR"

3. Tighten the terminal screws to ensure adequate contact.

Surges/Transients The transmitter will withstand electrical transients encountered through static

discharges or induced switching transients. However, a transient protection

option (option code T1) is available to protect the 848L against high-energy

transients. The device must be properly grounded using the ground terminal.

GROUNDING Although not required, a ground terminal is provided that can be connected to

earth ground for optimal EMC performance. A wire of 14AWG or larger is

recommend using appropriate terminal connectors at both ends.

Transmitter Enclosure (optional)

Ground the transmitter in accordance with local electrical requirements.

SWITCHES

Figure 2-5. Switch Location on

the Rosemount 848L

848/848L/848L_19_AA.EPS

NOT USED

SECURITY

SIMULATE ENABLE

848/848L/848L_17_AA.EPS

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Rosemount 848L

2-6

Security

After configuring the transmitter, the data can be protected from unwarranted

changes. Each 848L is equipped with a security switch that can be positioned

“ON” to prevent the accidental or deliberate change of configuration data.

This switch is located on the front side of the electronics module and

is labeled SECURITY.

See Figure 2-5 on page 2-5 for switch location on the transmitter label. Refer

to Section 3: Configuration, “SOFT WRITE LOCK and HARD WRITE LOCK”

on page 3-5.

Simulate Enable

The switch labeled SIMULATE ENABLE is used in conjunction with the with

the Discrete Input (DI) and Discrete Output (DO) function blocks. This switch

is used to simulate input status. As a lock-out feature, the switch must

transition from “OFF” to “ON” after power is applied to the transmitter. This

feature prevents the transmitter from being left in simulator mode.

NOT USED

The switch labeled NOT USED is only used for product engineering and

development purposes and should always remain in the “OFF” position. If the

switch is turned to the “ON” position and power is applied, the 848L will not be

present on the fieldbus segment.

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September 2004

2-7

Rosemount 848L

I/O WIRING

848/848L/848L_10_AA, 848L_11_AA, 848L_12_AA, 848L_13_AA, 848L_14_AA.EPS

DISCRETE INPUT WIRING CONFIGURATION

2-Wire NAMUR Sensors

1 of 2 Input Connectors Dry Contact Switches

1 of 2 Input Connectors

3-Wire NAMUR Sensors

1 of 2 Input Connectors

9-32 VDC Sensors

1 of 2 Input Connectors

DISCRETE OUTPUT WIRING CONFIGURATION

9-32 VDC Outputs

Reference Manual

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September 2004

Rosemount 848L

2-8

TAGGING Commissioning Tag

The 848L is supplied with a removable commissioning tag that contains both

the Device ID (the unique code that identifies a particular device in the

absence of a device tag) and a space to record the device tag (the operational

identification for the device as defined by the Piping and Instrumentation

Diagram (P&ID)).

When commissioning more than one device on a fieldbus segment, it can be

difficult to identify which device is at a particular location. The removable tag,

provided with the transmitter, can aid in this process by linking the Device ID

to its physical location. The installer should note the physical location of the

transmitter on both the upper and lower location of the commissioning tag.

The bottom portion should be torn off for each device on the segment and

used for commissioning the segment in the control system.

Figure 2-6. Commissioning Tag

Transmitter Tag

Hardware

• tagged in accordance with customer requirements

• permanently attached to the transmitter

Software

• the transmitter can store up to 30 characters

• if no characters are specified, the first 30 characters of the hardware tag

will be used

Sensor Tag

Hardware

• a plastic tag is provided to record identification of the I/O

• in the field, the tag can be removed, printed on, and reattached to the

transmitter

Software

• the I/O Transducer Block provides the ability to record the I/O tags.

Device ID

Device Tag

to denote

physical

location

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September 2004

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Rosemount 848L

TRANSMITTER LABEL

Figure 2-7. Transmitter Label

INSTALLATION

Using Cable Glands Use the following steps to install the 848L with Cable Glands:

1. Remove the junction box cover by unscrewing the four cover screws.

2. Run the sensor and power/signal wires through the appropriate cable

glands using the pre-installed cable glands (see Figure 2-8).

3. Install the I/O wires into the correct screw terminals.

4. Install the power/signal wires onto the correct screw terminals. Bus

power is polarity insensitive, allowing the user to connect positive (+)

or negative (–) to either Fieldbus wiring terminal labeled “Bus.” I/O

power is polarity sensitive and must be connected correctly to avoid

damage to the transmitter. See Figure 2-4 on page 2-5.

5. Replace the enclosure cover and securely tighten all cover screws.

Figure 2-8. Installing the 848L

with Cable Glands

848/848_21_AA.EPS

Cable Gland

Power/Signal

I /O

848_848A19A

Enclosure Cover

Screw (4)

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September 2004

Rosemount 848L

2-10

Using Conduit Entries Use the following steps to install the 848L with Conduit Entries:

1. Remove the junction box cover by unscrewing the four cover screws.

2. Remove the five conduit plugs and install five conduit fittings

(supplied by the installer).

3. Run sensor and output wires through each conduit fitting.

4. Install the I/O wires into the correct screw terminals.

5. Install the power/signal wires into the correct screw terminals. Bus

power is polarity insensitive, allowing the user to connect positive (+)

or negative (–) to either Fieldbus wiring terminal labeled “Bus.” I/O

power is polarity sensitive and must be connected correctly to avoid

damage to the transmitter. See Figure 2-4 on page 2-5.

6. Replace the junction box cover and securely tighten all cover screws.

Figure 2-9. Installing the 848L

with Conduit Entries

Enclosure

Cover Screw

Power/Signal

Conduit

I /O

848_848A09A

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Section 3 Configuration

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-1

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-1

General Block Information . . . . . . . . . . . . . . . . . . . . . . . . . page 3-2

Resource Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-4

I/O Transducer Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-9

Logic Transducer Block . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-10

Discrete Input Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-20

Discrete Output Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3-21

Multiple Discrete Input Block . . . . . . . . . . . . . . . . . . . . . . page 3-21

Multiple Discrete Output Block . . . . . . . . . . . . . . . . . . . . . page 3-21

OVERVIEW This section covers basic operation, software functionality, and basic

configuration procedures for the Rosemount 848L transmitter with

FOUNDATION fieldbus. This section is organized by block information. For

detailed information about the function blocks used in the Rosemount 848L

logic transmitter, refer to “Foundation Fieldbus Block Information” on page A-1

and the Foundation Fieldbus Function Block manual (00809-0100-4783).

SAFETY MESSAGES Procedures and instructions in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that

raises potential safety issues is indicated by a warning symbol ( ). Refer to

the following safety messages before performing an operation preceded by

this symbol.

Warnings

Explosions can result in death or serious injury.

Before connecting a configuration tool in an explosive atmosphere, make sure the

instruments in the loop are installed in accordance with nonincendive field wiring

practices.

Electrical shock can result in death or serious injury.

• Avoid contact with the leads and terminals. High voltage that may be present

on leads can cause electrical shock.

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September 2004

Rosemount 848L

3-2

GENERAL BLOCK

INFORMATION

Modes The Resource, Transducer, and all function blocks in the device have modes

of operation. These modes govern the operation of the block. Every block

supports both automatic (AUTO) and out of service (OOS) modes. Other

modes may also be supported.

Changing Modes

To change the operating mode, set the MODE_BLK.TARGET to the desired

mode. After a short delay, the parameter MODE_BLOCK.ACTUAL should

reflect the mode change if the block is operating properly.

Permitted Modes

It is possible to prevent unauthorized changes to the operating mode of a

block. To do this, configure MODE_BLOCK.PERMITTED to allow only the

desired operating modes. It is recommended to always select OOS as one of

the permitted modes.

Types of Modes

For the procedures described in this manual, it will be helpful to understand

the following modes:

AUTO

The functions performed by the block will execute. If the block has any

outputs, these will continue to update. This is typically the normal

operating mode.

Out of Service (OOS)

The functions performed by the block will not execute. If the block has any

outputs, these will typically not update and the status of any values passed

to downstream blocks will be “BAD”. To make some changes to the

configuration of the block, change the mode of the block to OOS. When

the changes are complete, change the mode back to AUTO.

MAN

In this mode, variables that are passed out of the block can be manually

set for testing or override purposes.

Other Types of Modes

Other types of modes are Cas, RCas, ROut, IMan and LO. Some of these

may be supported by different function blocks in the Rosemount 848L. For

more information, see the Function Block manual, document

00809-0100-4783.

NOTE

When an upstream block is set to OOS, this will impact the output status of all

downstream blocks. The figure below depicts the hierarchy of blocks:

Resource

Block

Transducer

Block

Discrete Input

(DI Block)

Other

function

blocks

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September 2004

3-3

Rosemount 848L

Link Active Scheduler The Rosemount 848L can be designated to act as the backup Link Active

Scheduler (LAS) in the event that the LAS is disconnected from the segment.

As the backup LAS, the Rosemount 848L will take over the management of

communications until the host is restored.

The host system may provide a configuration tool specifically designed to

designate a particular device as a backup LAS. Otherwise, this can be

configured manually as follows:

1. Access the Management Information Base (MIB) for the Rosemount

848L.

2. To activate the LAS capability, write 0x02 to the

BOOT_OPERAT_FUNCTIONAL_CLASS object (Index 605). To

deactivate, write 0x01.

3. Restart the processor.

Block Instantiation Rosemount devices are pre-configured with function blocks at the factory, the

default permanent configuration for the Rosemount 848L is listed below. The

Rosemount 848L can have one additional instantiated function block.

• 8 Discrete Input Blocks

• 4 Discrete Output Blocks

• Multiple Discrete Input Block

• Multiple Discrete Output Block

The Rosemount 848L supports the use of Function Block Instantiation. When

a device supports block instantiation, the number of blocks and block types

can be defined to match specific application needs.The number of blocks that

can be instantiated is only limited by the amount of memory within the device

and the block types that are supported by the device. Instantiation does not

apply to standard device blocks like the Resource, I/O Transducer, and Logic

Transducer Block.

Block instantiation is done by the host control system or configuration tool, but

not all hosts are required to implement this functionality. Please refer to your

specific host or configuration tool manual for more information.

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September 2004

Rosemount 848L

3-4

Capabilities Virtual Communication Relationship (VCRs)

There are a total of 20 VCRs. Two are permanent and 18 are fully

configurable by the host system. 25 link objects are available.

Host timer recommendations

T1 = 96000

T2 = 1920000

T3 = 480000

Block Execution times

Discrete Input = 40 ms

Discrete Output = 40 ms

Multiple Discrete Input = 40 ms

Multiple Discrete Output = 40 ms

RESOURCE BLOCK

FEATURES and

FEATURES_SEL

The parameters FEATURES and FEATURE_SEL determine optional

behavior of the Rosemount 848L.

FEATURES

The FEATURES parameter is read only and defines which features are

supported by the Rosemount 848L. Below is a list of the FEATURES the

Rosemount 848L supports.

UNICODE

All configurable string variables in the Rosemount 848L, except tag names,

are octet strings. Either ASCII or Unicode may be used. If the configuration

device is generating Unicode octet strings, you must set the Unicode option

bit.

REPORTS

The Rosemount 848L supports alert reports. The Reports option bit must be

set in the features bit string to use this feature. If it is not set, the host must

poll for alerts.

Network Parameter Value

Slot Time 8

Maximum Response Delay 4

Maximum Inactivity to Claim LAS Delay 60

Minimum Inter DLPDU Delay 7

Time Sync class 4 (1ms)

Maximum Scheduling Overhead 21

Per DLPDU PhL Overhead 4

Maximum Inter-channel Signal Skew 0

Required Number of Post-transmission-gap-ext Units 0

Required Number of Preamble-extension Units 1

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September 2004

3-5

Rosemount 848L

SOFT WRITE LOCK and HARD WRITE LOCK

Inputs to the security and write lock functions include the hardware security

switch, the hardware and software write lock bits of the FEATURE_SEL

parameter, the WRITE_LOCK parameter, and the DEFINE_WRITE_LOCK

parameter.

The WRITE_LOCK parameter prevents modification of parameters within the

device except to clear the WRITE_LOCK parameter. During this time, the

block will function normally updating inputs and outputs and executing

algorithms. When the WRITE_LOCK condition is cleared, a WRITE_ALM

alert is generated with a priority that corresponds to the WRITE_PRI

parameter.

The FEATURE_SEL parameter enables the user to select a hardware or

software write lock or no write lock capability. To enable the hardware security

function, enable the HW_SEL bit in the FEATURE_SEL parameter. When this

bit has been enabled the WRITE_LOCK parameter becomes read only and

will reflect the state of the hardware switch. In order to enable the software

write lock, the SW_SEL bit must be set in the FEATURE_SEL parameter.

Once this bit is set, the WRITE_LOCK parameter may be set to “Locked” or

“Not Locked.” Once the WRITE_LOCK parameter is set to “Locked” by either

the software or the hardware lock, all user requested writes as determined by

the DEFINE_WRITE_LOCK parameter shall be rejected.

The DEFINE_WRITE_LOCK parameter allows the user to configure whether

the write lock functions (both software and hardware) will control writing to all

blocks, or only to the resource and transducer blocks. Internally updated data

such as process variables and diagnostics will not be restricted by the

security switch.

The following table displays all possible configurations of the WRITE_LOCK

parameter.

FEATURE_SEL

FEATURE_SEL is used to turn on any of the supported features. The default

setting of the Rosemount 848L does not select any of these features. Choose

one of the supported features if any.

MAX_NOTIFY The MAX_NOTIFY parameter value is the maximum number of alert reports

that the resource can have sent without getting a confirmation, corresponding

to the amount of buffer space available for alert messages. The number can

be set lower, to control alert flooding, by adjusting the LIM_NOTIFY

parameter value. If LIM_NOTIFY is set to zero, then no alerts are reported.

FEATURE_SEL

HW_SEL bit

FEATURE_SEL

SW_SEL bit SECURITY SWITCH WRITE_LOCK

WRITE_LOCK

Read/Write DEFINE_WRITE_LOCK

Write access

to blocks

0 (off) 0 (off) NA 1 (unlocked) Read only NA All

0 (off) 1 (on) NA 1 (unlocked) Read/Write NA All

0 (off) 1 (on) NA 2 (locked) Read/Write Physical Function

Blocks only

0 (off) 1 (on) NA 2 (locked) Read/Write Everything None

1 (on) 0 (off)(1) 0 (unlocked) 1 (unlocked) Read only NA All

1 (on) 0 (off) 1 (locked) 2 (locked) Read only Physical Function

Blocks only

1 (on) 0 (off) 1 (locked) 2 (locked) Read only Everything None

(1) The hardware and software write lock select bits are mutually exclusive and the hardware select has the highest priority. When the HW_SEL bit if set to 1

(on), the SW_SEL bit is automatically set to 0 (off) and is read only.

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September 2004

Rosemount 848L

3-6

PlantWeb™ Alarms The Resource Block will act as a coordinator for PlantWeb alarms. There will

be three alarm parameters (FAILED_ALARM, MAINT_ALARM, and

ADVISE_ALARM) which will contain information regarding some of the device

errors which are detected by the transmitter software. There will be a

RECOMMENDED_ACTION parameter which will be used to display the

recommended action text for the highest priority alarm. FAILED_ALARM will

have the highest priority followed by MAINT_ALARM and ADVISE_ALARM

will be the lowest priority.

FAILED_ALARMS

A failure alarm indicates a failure within a device that will make the device or

some part of the device non-operational. This implies that the device is in

need of repair and must be fixed immediately. There are five parameters

associated with FAILED_ALARMS specifically, they are described below.

FAILED_ENABLED

This parameter contains a list of failures in the device which makes the

device non-operational that will cause an alarm to be sent. Below is a list

of the failures with the highest priority first.

1. Electronics Failure

2. NV Memory Failure

3. No I/O Power

4. Primary Value Failure

5. Secondary Value Failure

FAILED_MASK

This parameter will mask any of the failed conditions listed in

FAILED_ENABLED. A bit on means that the condition is masked out from

alarming and will not be reported.

FAILED_PRI

Designates the alarming priority of the FAILED_ALM. The default is 0 and

the recommended value is between 8 and 15.

FAILED_ACTIVE

This parameter displays which of the alarms is active. Only the alarm with

the highest priority will be displayed. This priority is not the same as the

FAILED_PRI parameter described above. This priority is not user

configurable.

FAILED_ALM

Alarm indicating a failure within a device which makes the device

non-operational.

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September 2004

3-7

Rosemount 848L

MAINT_ALARMS

A maintenance alarm indicates the device or some part of the device needs

maintenance soon. If the condition is ignored, the device will eventually fail.

There are five parameters associated with MAINT_ALARMS, they are

described below.

MAINT_ENABLED

The MAINT_ENABLED parameter contains a list of conditions indicating

the device or some part of the device needs maintenance soon. If the

condition is ignored, the device will eventually fail.

Below is a list of the conditions with the highest priority first.

1. Secondary Value Degraded

2. Configuration Error

MAINT_MASK

The MAINT_MASK parameter will mask any of the failed conditions listed

in MAINT_ENABLED. A bit on means that the condition is masked out

from alarming and will not be reported.

MAINT_PRI

MAINT_PRI designates the alarming priority of the MAINT_ALM. The

default is 0 and the recommended value is 3 to 7.

MAINT_ACTIVE

The MAINT_ACTIVE parameter displays which of the alarms is active.

Only the condition with the highest priority will be displayed. This priority is

not the same as the MAINT_PRI parameter described above. This priority

is not user configurable.

MAINT_ALM

An alarm indicating the device needs maintenance soon. If the condition is

ignored, the device will eventually fail.

Advisory Alarms

An advisory alarm indicates informative conditions that do not have a direct

impact on the device's primary functions There are five parameters

associated with ADVISE_ALARMS, they are described below.

ADVISE_ENABLED

The ADVISE_ENABLED parameter contains a list of informative

conditions that do not have a direct impact on the device's primary

functions. Below is a list of the advisories with the highest priority first.

1. Prescaler Overflow

2. NV Write Deferred

3. PWA Simulate Active

ADVISE_MASK

The ADVISE_MASK parameter will mask any of the failed conditions listed

in ADVISE_ENABLED. A bit on means the condition is masked out from

alarming and will not be reported.

ADVISE_PRI

ADVISE_PRI designates the alarming priority of the ADVISE_ALM. The

default is 0 and the recommended value is 1 or 2.

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September 2004

Rosemount 848L

3-8

ADVISE_ACTIVE

The ADVISE_ACTIVE parameter displays which of the advisories is

active. Only the advisory with the highest priority will be displayed. This

priority is not the same as the ADVISE_PRI parameter described above.

This priority is not user configurable.

ADVISE_ALM

ADVISE_ALM is an alarm indicating advisory alarms. These conditions do

not have a direct impact on the process or device integrity.

Recommended Actions for PlantWeb Alarms

RECOMMENDED_ACTION

The RECOMMENDED_ACTION parameter displays a text string that will

give a recommended course of action to take based on which type and

which specific event of the PlantWeb alarms is active.

Table 3-1.

RB.RECOMMENDED_ATION

Alarm Type

Failed/Maint/Advise

Active Event

Recommended Action

Text String

NONE None No action required

ADVISORY

Prescaler Overflow Check the Divisor parameter of all PS function

calls in the logic equations

NV Write Deferred Reduce the frequency in which applications

write to NV Memory

PWA Simulate Active Disable PWA_SIMULATE parameter in the

Resource Block

MAINTENANCE

Secondary Value

Degraded

Ensure that the transmitter is not too close to

extreme hot or cold environments

Configuration Error Verify that the Logic equations are correct in

the Logic transducer block

FAILED

Electronics Failure Replace the electronics

NV Memory Failure Replace the electronics

No I/O Power Check the IO Power supply, polarity, wiring,

and connections.

Primary Value Failure Check the sensor, configuration, wiring, and

connection for open or shorted sensors.

Secondary Value

Failure

Verify that the body temperature is within the

operating limits of this device.

Reference Manual

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September 2004

3-9

Rosemount 848L

Alarms Use the following steps to configure the alarms, which are located in the

Resource Block.

1. Set the resource block to OOS.

2. Set WRITE_PRI to the appropriate alarm level (WRITE_PRI has a

selectable range of priorities from 0 to 15. Set the other block alarm

parameters at this time.

3. Set CONFIRM_TIME to the time, in 1/32 of a millisecond, that the

device will wait for confirmation of receiving a report before trying

again (the device does not retry if CONFIRM_TIME is 0).

4. Set LIM_NOTIFY to a value between zero and MAX_NOTIFY.

LIM_NOTIFY is the maximum number of alert reports allowed before

the operator needs to acknowledge an alarm condition.

5. Enable the reports bit in FEATURE_SEL.

6. Set the resource block to AUTO.

I/O TRANSDUCER

BLOCK

The 848L is ordered with either Dry Contact, VDC or NAMUR Inputs. Each

input can have a filter which determines the minimum time a contact needs to

be at a given state to be acknowledged as a state change.

The following procedure allows the sensors to be configured:

1. Set MODE_BLK.TARGET to OOS

2. For each Input “n” select the parameter IN_n_CONFIG.FILTER

a. Select the desired filter time in the range of 0 to 128msec

3. Set MODE_BLK.TARGET to AUTO

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September 2004

Rosemount 848L

3-10

The 848L can force the outputs to a predetermined state in the event of a

device malfunction.

The following procedure can be used to set the fail safe condition for each

output:

1. Set MODE_BLK.TARGET to OOS

2. For each Output "n" select the parameter

OUT_n_CONFIG.FAIL_SAFE

3. Select False, True or Last Good Value

4. Set MODE_BLK.TARGET to AUTO

Latching

Most often the inputs are scanned and the logic equations processed at a rate

greater than the macrocycle frequency. To be certain that positive or negative

transitions are communicated, the inputs, equation results, and output values

can be latched until read by the function blocks.

The following procedure is used to set the latching state of each input,

equation or output:

1. Set MODE_BLK.TARGET to OOS

2. Select the appropriate parameter for either inputs, equations, or

outputs:

a. Inputs use parameter MACRO_IN_LATCH

b. Outputs use parameter MACRO_OUT_LATCH

c. Equations use parameter MACRO_EQ_LATCH

For each input, output or equation select either "Latch Positive Pulses" or

"Latch Negative Pulses" or “disabled”.

LOGIC TRANSDUCER

BLOCK

Logic Equations

The 848L provides for 16 Logic Equations and 4 Output Equations. The

Output Equations drive the hardware outputs. Each logic equation consists of

up to 80 characters with a semicolon as the last character. The equations are

evaluated at a nominal rate of 100msec. However this will vary based on the

number and complexity of the equations used. The logic block consists of

variables that are connected to the hardware I/O, obtain values or send

values over the bus and internally calculated variables as shown in

Figure 3-1.

The value or state of the logic block variables can be communicated on the

bus by assigning the appropriate channel number of a DI or MDI block. The

DO variables can be set externally by assigning the appropriate channel

number in a DO or MDO function block. The DO function blocks do not drive

the outputs directly. The DO function block can drive the output by referencing

the appropriate DO variable in the output equations.

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Figure 3-1. 848L Logic

Transmitter Data Flow

Logic Transducer Block

Hardware

Inputs

Hardware

Outputs

IN_1

IN_2

IN_3

IN_4

IN_5

IN_6

IN_7

IN_8

OUT_1

OUT_2

OUT_3

OUT_4

16 Logic

Equations

4 Output

Equations

EQ_1

EQ_16

DI Block

DO Block

DO Channel

Any DO

-----------------

8 Packed DOs

DI Channel

Any IN

Any EQ

Any OUT

---------------

8 Packed INs

First 8 Packed EQs

Last 8 Packed EQs

4 Packed OUTs

Sensor Transducer Block

Sensor & Output Configuration

MDI Block

8 Inputs

MDI Channels

ALL INs

First EQs

Last EQs

All OUTs

MDO Block

8 Outputs

MDO Channel

All DOs

OUT

OUT_1

OUT_8

IN_1

IN_8

DO_1

DO_2

DO_3

DO_4

DO_5

DO_6

DO_7

DO_8

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The following characters are allowed in a logic equation:

• Uppercase and lowercase alphabet, case insensitive, used to specify

functions

• Digits 0-9, used to specify channel numbers and unsigned integer

constants

• Comma, used to separate parameters in a function parameter list

• Parentheses() used to define the extent of the parameter list of a

function

• Semicolon; used to terminate an equation

• Space (not tab), ignored by parser, may be used to make an equation

more readable but counts as a character

The following characters are specifically not allowed in a logic:

• The period (dot) character is not allowed. There are no decimal

numbers.

• The unary minus (-) character is not allowed. There are no negative

integers.

• The math operators (+, -, *, /, **) are not allowed, nor are symbols for

any logic operators (&, |, <, >, ...).

Functions must be from the list of Logic Functions below, and must have the

specified number of parameters.

Channel Functions

The following functions read channel value and status. The number of

instances of these functions is unlimited, except for PS. A channel value and

status is set by the I/O processor at the beginning of an equation evaluation

cycle, by the equations as they complete evaluation, or by macrocycle

evaluations of any DO blocks attached to channels 9 through 16. The status

of channels 9-16 is always good, even if the DO block has a bad status.

IN - The input hardware sets the values of channels 1-8. Configured DI blocks

may specify these channels in order to read the specified hardware input. The

value of an input may be referenced in an equation by the IN (i) function,

where the channel number is placed between the parentheses. The range of

‘i’ is 1 to 8. Multiple references to any channel are allowed.

ICR, ICF - I/O samples are taken every millisecond, which is considerably

faster than equation executions. It is possible for an input to turn on and turn

off during an equation evaluation cycle, so that it would not be seen by an

IN (i) function. Each input has a counter for transitions (rise or fall). A

transition is based on the output of the debounce filter, not the raw input.

Filtering can be set to zero. The counter is read and cleared at the beginning

of each evaluation cycle. The method relies completely on the counter and

does not use the latch configuration. The ICR (i) function is true for one

evaluation cycle if a rising transition occurred, and its opposite ICF (i) is true

for a falling transition.

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PS - When the hardware input consists of a continuous train of pulses at a

rate less than 500 PPS, a prescaler can be used to reduce the pulse rate to

something that does not change faster than the equation evaluation rate. The

function is PS (i, divisor) where ‘i’ is the channel number (1-8) and ‘divisor’ is

the number of pulses to count before setting its output true for one equation

evaluation cycle. The counter rolls over at ‘divisor’ and keeps counting. The

user must assure that there is always at least one execution cycle with a false

value from PS for every true value. If the pulse rate exceeds the divisor times

two, then the function returns Bad status and optionally a PlantWeb alert can

be sent. Only ten of these functions are available because they require

storage for previous values.

DO - Channels 9-16 are zero unless set by configured DO or MDO function

blocks. This allows a function block link to set the value from a remote

function block output or HMI screen switch. The values may be referenced in

equations by the DO (d) function. The range of ‘d’ is 1 to 8. To directly drive an

output from an external device the Output Equation would reference DO(d).

NOTE

The value of DO can change during an evaluation cycle if the macrocycle

evaluates the DO block. This may require referencing the DO value in a single

equation to “save” its state.

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EQ - Channels 17-32 are set by the result of an equation specified by up to 80

characters and stored in parameter EQx, where x is the equation number. The

equation results are available as a discrete value and status in parameter

EQx_VALUE. They may be referenced by the EQ (u) function. The range of

‘u’ is 1 to 16. These are intended to be intermediate values that are used

because the value is used in other equations or because the equation text

was too long. A configured DI block may use an equation channel (range 17

to 36) in order to make the result available to other devices.

OUT – The value will be the same as the requested output.

Additional Channels

The ten channels that are used for connecting multiple in or out function

blocks can not be referred to by equation functions. Each has a status that is

Bad if any Input status is Bad. Channels 37 to 41 pack the values into one

byte so that a DI or DO function block can read or write them. Any block linked

to a DI block with packed data must be capable of handling the packed

boolean values. Channels 42 to 46 may be used with standard MDI or MDO

blocks.

Reading a channel value will reset all of the channel latches that are

configured. Channels 38 and 43 do not have latches. If a DI and a MDI are

both used they will interfere with the latches, but the user is expected to use

one or the other, never both.

Channel Type FB

37 All IN DI

38 All DO DO

39 First 8 EQ DI

40 Last 8 EQ DI

41 All OUT DO

42 All IN MDI

43 All DO MDO

44 First 8 EQ MDI

45 Last 8 EQ MDI

46 All Out MDO

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Logic Functions

A function has a name and a set of one or more arguments contained within a

closed set of parentheses. The seven channel reference functions (IN, ICF,

ICR, PS, DO, EQ, and OUT) have been described above. These are the only

functions that take a channel number as an argument. The other functions

require functions for all arguments unless the last argument is a constant

number.

When a function is evaluated, it leaves its true or false value behind to be

evaluated by the next function or used as the result of evaluating the

equation. This is the result of using a simple and fast evaluation method

known as Reverse Polish Notation (RPN). The RPN method requires nesting

the functions like OR(IN(1),IN(2)) rather than using operator notation like

IN(1) | IN(2). This can lead to the following:

AND(IN(1),OR(IN(2),AND(IN(3),OR(IN(4),AND(IN(5),OR(IN(6),AND(IN(7),

(IN(8))))))));

The equation is evaluated by evaluating the deepest functions first, IN(7) and

(IN(8). If they are both true then the AND function evaluates to true. Then

IN(6) is evaluated, then the OR evaluates to true, and so on working up from

the deepest level in reverse order until the first (and top level) AND can be

evaluated. The result is stored in the channel specified by EQx, which

contains the text of the equation as explained above.

Drawn as a ladder logic, the equation would look like the figure below:

848L/LOGIC_FUNC_EXAMPLE.JPG

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Logic Operator Functions

The following combinatorial operators require a minimum of 2 and a maximum

of 10 functions between the parentheses, each separated by a comma.

AND ( ) - Performs the logical ‘and’ of the argument functions.

OR ( ) - Performs the logical ‘or’ of the argument functions.

XOR ( ) - Performs the logical exclusive ‘or’ of the argument functions. An

XOR function is false if all of the arguments are the same value, either all true

or all false. Otherwise it is true.

The following unary operator requires just one argument:

NOT ( ) - Performs the logical inversion of the argument function.

Limits on Functions

There is no limit to the number of functions described above, as long as they

fit within the 20 equations described by 80 character strings. The following

functions are limited to 10 of each within the entire set of 20 equations. This is

because the functions require memory to store constants or last values. The

size of a memory element is 16 bits, so the maximum size of a constant value

is 65535. There are no signed numbers.

Edge Detection Functions

RISE ( ) - This function evaluates as false unless the previous value of the

argument was false and now the argument evaluates to true. This function is

true for only one equation evaluation cycle. It will always be false on the

following cycle.

FALL( ) - This function evaluates as false unless the previous value of the

argument was true and now the argument evaluates to false. This function is

true for only one equation evaluation cycle. It will always be false on the

following cycle.

Clock Function

NOTE

All arguments of time are in tenths of a second.

CLOCK (onTime,offTime) - The parameters onTime and offTime are

constants. This function does not take other functions. CLOCK runs

unconditionally with a period determined by onTime plus offTime. Time is

specified in tenths of a second. The function will be true for onTime tenths of a

second. On the first evaluation cycle after the device starts up, the onTime

interval will start because all of the dynamic values are zero. Use the NOT

function to invert this behavior, and swap the on and off times.

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Counter Functions

CTU (clock, reset, target)- The parameters clock and reset are functions. The

target is a 16 bit constant. Whenever reset is true, the internal counter is set to

zero and the value of the function is false. The value of clock is ignored while

reset is true. If reset is false, the internal counter will increment once for each

rise of the clock parameter. When the internal counter equals the target value,

the value of the function is true and the counter stops counting in order to

avoid rollover. The value of the function is false if the internal counter does not

equal the target.

The internal counter is not visible from Fieldbus and is not available to any

other function. The value of the internal counter is not retained during a device

restart. This function is not suitable for a totalizer, but can be used as a

prescaler to adjust the external mechanical counter rate. The pulse rate must

be less than five per second.

The following expression increments the counter whenever hardware input 1

turns on. The counter is reset whenever hardware input 2 is on. If input one is

from a mechanical displacement flowmeter that delivers 76.54 pulses per

gallon, then the highest flow rate is 3.5 gallons per minute. The following

equation will deliver one 0.1 second pulse per 100 gallons:

OUT1_EQ contains CTU(IN(1),OUT(1),7654);

Starting at zero, 7653 pulses go by and then pulse 7654 turns on the output.

On the next evaluation cycle, the counter is reset because Output 1 is on.

This is a result of the order of execution of equations. Output 1 becomes true

because the count is reached, but the OUT(1) function has already been

evaluated as false. The counter must reset before the next pulse comes in.

The output pulse may be extended with a TP function.

TON (power, target) - Whenever power is false, the value of the internal timer

is set to zero and the value of the function is false. When power is true then

the value of the function will become true after the target amount f time has

elapsed. This condition persists as long as power is true. The timer resets

when power is false.

The following equation filters the level switch in a stirred tank so that high

level bouncing of the float does not create nuisance alarms for the operator.

Hardware input 1 senses the level switch and hardware output 1 drives the

alarm annunciator with its big horn. The level switch must stay closed for 5

minutes before the alarm is energized and the operator is startled by the horn.

OUT1_EQ contains: TON(IN(1),3000);

TOF (power, target) - Whenever power is true, the value of the internal timer is

set to the target and the value of the function is true. The value of the function

will become false after the target amount of time has elapsed. This condition

persists as long as power is false.

The following equation keeps the outlet valve open for about 5 seconds after

the pump is shut off, so that the pressure across the pump can equalize.

Hardware output 1 runs the pump and hardware output 2 opens the valve

OUT1_EQ contains: <something that controls the pump>;

OUT2_EQ contains: TOF(OUT(1),50);

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TP (power, target) - Whenever power transitions from false to true, the value

of the internal timer is set to the target and the value of the function is true.

The value of the function will become false after the target amount of time has

elapsed. This function is similar to TOF except that a timing cycle is only

initiated by the rise of power. Power may go false or stay true without affecting

the timing cycle. The cycle is restarted anytime that power goes true after the

function has had at least one evaluation cycle as false.

Latching Functions

A latch is a two state device that can be set to true or reset to false. It will

retain its state when both commands are false. It will not retain its state

through a device restart. The initial state is Reset. Two latch functions are

required to define the behavior when both commands are true, depending on

which state should be dominant. The result of the function is the state of the

latch.

SR (set, reset) - The parameters set and reset are functions. If both are true

then set wins and the result of the function is true.

RS (set, reset) - The parameters set and reset are functions. If both are true

then reset wins and the result of the function is false.

Shifting Functions

A shift register is a set of bits that moves each bit to the next bit position when

the command to shift is given. The vacant bit is filled with the value of the

input. The 848L shift functions contain 8 bit registers. The bit parameter

selects the bit in the register to test. The value of the function is the value of

the tested bit. The shift may be to the left or the right. The following table

shows the state of the register for three shifts after the register has been

reset. The input is true during the first shift evaluation and false thereafter.

The right most bit is bit 1 and the left most bit is bit 8.

The reset parameter clears the register, overriding both input and shift. Reset

is an optional parameter, but the function can be written with three parameters

or four. Do not use an extra comma if reset is omitted.

The register data will be cleared on a processor restart (i.e. power cycle).

SHL (input, shift, reset, testbit) - The parameters input, shift, and reset are

functions. The parameter testbit is a constant that is constrained to be in the

range of 1 to 8. The reset function is optional. If reset is present and true, the

8 bit register is cleared to zero and the result of the function is false.

Otherwise, if shift is true then bit 7 will be moved to bit 8, bit 6 to bit 7, bit 5 to

bit 6, bit 4 to bit 5, bit 3 to bit 4, bit 2 to bit 3, bit 1 to bit 2, and the value of input

will become the value of bit 1. Then the bit specified by testbit will be tested to

determine the value of the function.

Direction Reset Shift 1 Shift 2 Shift 3

Left 00000000 00000001 00000010 00000100

Right 00000000 10000000 01000000 00100000

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SHR (input, shift, reset, testbit) - The parameters input, shift and reset are

functions. The parameter testbit is a constant that is constrained to be in the

range of 1 to 8. The reset function is optional. If reset is present and true, the

8 bit register is cleared to zero and the result of the function is false.

Otherwise, if shift is true then bit 2 will be moved to bit 1, bit 3 to bit 2, bit 4 to

bit 3, bit 5 to bit 4, bit 6 to bit 5, bit 7 to bit 6, bit 8 to bit 7, and the value of input

will become the value of bit 8. Then the bit specified by testbit will be tested to

determine the value of the function.

The following procedure is used to enter the logic equations.

1. Set MODE_BLK.TARGET to OOS

2. Enter the equations in parameters EQn where n=1 to 16 or

OUT1_EQ, OUT2_EQ, OUT3_EQ or OUT4_EQ. Each equation

ending with a semicolon.

3. Set the MODE_BLK.TARGET to AUTO

The equations will then be evaluated and the status of the evaluation shown

in the parameter PARSE_RESULT. If any errors were found the block will

remain in the OOS mode.

Status Propagation

The contact and Boolean value has a binary value and a good/bad status.

A status is applied to a channel value in one of the following ways:

The hardware input device maybe able to tell if it is shorted or open, in

addition to on or off. If the hardware cannot tell then the status is always

good, unless a device failure prevents reading the I/O data.

The evaluation of an equation propagates either Good Non-cascade or

Bad, both Non-specific.

Each function that is evaluated determines both a value and a status of either

good or bad. The functions that provide status are the functions that test a

channel number - IN, ICF, ICR, OUT, DO, PS and EQ. If any of the function’s

parameters have a Bad or Uncertain status with any sub-status then the

function terminates and returns a bad status, otherwise it returns a good value

and status.

When an equation (set of functions) is evaluated, if a function returns a bad

status then evaluation of that equation stops, and the equation channel status

is set to Bad, Non-specific. If evaluation goes to completion, the channel

status will be set to Good Process, Non-specific, not limited.

Status propagates forward, in the direction of the last output equation. If a

function references an equation that is the equation being evaluated or a later

equation, then the status of that equation will be ignored. The function will use

the last good value of the referenced equation and call its status Good. This

prevents forward references to equations that reference this equation from

locking both equations into Bad status if either ever sets Bad status.

During initialization of the logic transducer block, before the first execution,

each equation channel status is set to Bad, Non-specific, constant and the

value is set to False.

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Logic Execution Timing

The Logic transducer block reads the hardware inputs, processes the

equations and drives the outputs on a continuous cycle. The cycle time or

frequency of execution will vary depending on the number and type of logic

functions used in the equations.

DISCRETE INPUT

BLOCKS

The DI blocks are used to communicate the current value of a contact, the

state of one of the Boolean equations, or the state of an output. The DI block

chooses the value through the Channel parameter. Alternatively, the DI block

can be configured to pass 8 values in a packed format to the host system

(DeltaV) by using channels 7 to 41. To set the channel number use the

following procedure for each DI block.

1. Set MODE_BLK.TARGET to OOS

2. Select the Channel parameter

3. Select the desired channel number

4. Set MODE_BLK.TARGET to AUTO

Channel 1= “Input 1” Channel 24= “EQ 8”

Channel 2= “Input 2” Channel 25= “EQ 9”

Channel 3= “Input 3” Channel 26= “EQ 10”

Channel 4= “Input 4” Channel 27= “EQ 11”

Channel 5= “Input 5” Channel 28= “EQ 12”

Channel 6= “Input 6” Channel 29= “EQ 13”

Channel 7= “Input 7” Channel 30= “EQ 14”

Channel 8= “Input 8” Channel 31= “EQ 15”

Channel 9= “DO 1” Channel 32= “EQ 16”

Channel 10= “DO 2” Channel 33= “Output 1”

Channel 11= “DO 3” Channel 34= “Output 2”

Channel 12= “DO 4” Channel 35= “Output 3”

Channel 13= “DO 5” Channel 36= “Output 4”

Channel 14= “DO 6” Channel 37= “Packed Inputs”

Channel 15= “DO 7” Channel 38= “Packed DO”

Channel 16= “DO 8” Channel 39= “Packed EQ1”

Channel 17= “EQ 1” Channel 40= “Packed EQ2”

Channel 18= “EQ 2” Channel 41= “Packed Outputs”

Channel 19= “EQ 3” Channel 42= “Array Inputs” (MDI Only)

Channel 20= “EQ 4” Channel 43= “Array DO” (MDI Only)

Channel 21= “EQ 5” Channel 44= “Array EQ1” (MDI Only)

Channel 22= “EQ 6” Channel 45= “Array EQ2” (MDI Only)

Channel 23= “EQ 7” Channel 46= “Array Outputs” (MDI Only)

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Simulation

Simulation replaces the channel value coming from the transducer block for

testing purposes.

The following procedure is used to simulate a DI output.

To change the output value place the Target Mode of the block to Manual

and then change the OUT_D.VALUE to the desired value.

To simulate both the value and status do the following:

1. If the Simulate Switch is in the OFF position, move it to ON. If the

Simulate switch is already in the ON position, you must move it to Off

an place it back in to the ON position.

NOTE

As a safety measure, the switch must be reset every time power is interrupted

to the device in order to enable SIMULATE. This prevents a device that is

tested on the bench from getting installed in the process with SIMULATE still

active.

2. To change both the OUT_D.VALUE and OUT_D.STATUS of the DI

Block, set the TARGET MODE to AUTO.

3. Set SIMULATE_D.ENABLE_DISABLE to ‘Active’.

4. Enter the desired values for SIMULATE_D. SIMULATE_VALUE and

SIMULATE_D. SIMULATE_STATUS.

If errors occur when performing the above steps, be sure that the SIMULATE

switch has been reset after powering up the device.

DISCRETE OUTPUT

BLOCKS

The digital output blocks are used to receive a value from another device to

be used to either drive a contact output or to use in the logic equations. The

DO blocks make their values available to the 848L by placing the value in a

variable called DO (n) where n=1 to 8. Like the DI block, all eight outputs can

be communicated in a packed format by selecting the appropriate channel

number. The DO block does not drive the outputs directly but sets the state of

the internal variables DO(n). To drive an output from the DO block, the DO(n)

variable is placed in one of the output equations.

OUT1_EQ = DO(1);

MULTIPLE DISCRETE

INPUT BLOCK

The MDI block allows 8 values with their status in one block with 8 individual

outputs. The 8 values are selected by one of the “Array” channel numbers.

MULTIPLE DISCRETE

OUTPUT BLOCK

The MDO block allows 8 output values with their status in one block with 8

individual inputs. The 8 values are selected by the “Array Outputs” channel

number.

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www.rosemount.com

Section 4 Operation and Maintenance

Safety Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-1

Foundation Fieldbus Information . . . . . . . . . . . . . . . . . . . page 4-1

Hardware Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-2

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4-3

SAFETY MESSAGES Instructions and procedures in this section may require special precautions to

ensure the safety of the personnel performing the operations. Information that

potentially raises safety issues is indicated by a warning symbol ( ). Please

refer to the following safety messages before performing an operation

preceded by this symbol.

Warnings

FOUNDATION FIELDBUS

INFORMATION

FOUNDATION fieldbus is an all-digital, serial, two-way, multidrop

communication protocol that interconnects devices such as transmitters and

valve controllers. It is a local area network (LAN) for instruments that enables

basic control and I/O to be moved to the field devices. The Rosemount 848L

uses FOUNDATION fieldbus technology developed and supported by Emerson

Process Management and the other members of the independent Fieldbus

Foundation.

Failure to follow these installation guidelines could result in death or

serious injury.

• Make sure only qualified personnel perform the installation.

Electrical shock could cause death or serious injury.

• If the device or sensors are installed in a high voltage environment and a fault

condition or installation error occurs, high voltage may be present on transmitter

leads and terminals.

• Use extreme caution when making contact with the leads and terminals.

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4-2

Commissioning

(Addressing)

To be able to setup, configure, and have a device communicate with other

devices on a segment, a device must be assigned a permanent address.

Unless requested otherwise, it is assigned a temporary address when

shipped from the factory.

If there are two or more devices on a segment with the same address, the first

device to start up will use the assigned address (ex. Address 20). Each of the

other devices will be given one of the four available temporary addresses. If a

temporary address is not available, the device will be unavailable until a

temporary address becomes available.

Use the host system documentation to commission a device and assign a

permanent address.

HARDWARE

MAINTENANCE

The 848L has no moving parts and requires a minimal amount of scheduled

maintenance. If a malfunction is suspected, check for an external cause

before performing the diagnostics presented below. The 848L has a green

LED which indicates that the device has both DC I/O power and power from

the bus. Once powered the green LED will remain illuminated as long as the

I/O power is available even if bus power is lost.

The red LED indicates that the Resource block is Out of Service. Any

hardware fault detected except open or shorted sensors will place the

Resource block in the Out of Service mode.

Sensor Check The amber LEDs indicate if the 848L is detecting the sensor as open or

closed. To check the input circuit you can connect a working sensor at the

transmitter and check it's operation. Consult an Emerson Process

Management representative for additional assistance.

It is possible that the sensor LEDs do not reflect the actual state of a sensor

since they are activated by the electronics and not directly by the sensor. Use

appropriate electrical test equipment to verify actual sensor states.

Communication/Power

Check

If the transmitter does not communicate or provides an erratic output, check

for adequate voltage to the transmitter. The transmitter requires between 9.0

and 32.0 VDC at the bus terminals to operate with complete functionality.

Check for wire shorts, open circuits, and multiple grounds.

Resetting the

Configuration

(RESTART)

There are two types of restarts available in the Resource Block. The following

section outlines the usage for each of these.

Restart Processor (cycling)

Performing a Restart Processor has the same effect as removing power from

the device and reapplying power.

Restart with Defaults

Performing a Restart with Defaults resets the static parameters for all of the

blocks to their initial state. This is commonly used to change the configuration

and/or control strategy of the device, including any custom configurations

done at the Rosemount factory.

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TROUBLESHOOTING

FOUNDATION Fieldbus

Resource Block

I/O Transducer and Logic Block Troubleshooting

NAMUR Sensors

Symptom Possible Cause Corrective Action

Device does not show

up in the live list

Network configuration parameters

are incorrect

Set the network parameters of the LAS (host system) according to the FF

Communications Profile

ST: 8

MRD: 10

DLPDU PhLO: 4

MID: 7

TSC: 4 (1 ms)

T1: 1920000 (60 s)

T2: 5760000 (180 s)

T3: 480000 (15 s)

Network address is not in polled

range

Set first Unpolled Node and Number of UnPolled Nodes so that the device

address is within range

Power to the device is below the

9 VDC minimum

Increase the power to at least 9V

Noise on the power /

communication is too high

Verify terminators and power conditioners are within specification

Verify that the shield is properly terminated and not grounded at both ends. It is

best to ground the shield at the power conditioner

Device that is acting as

a LAS does not send

out CD

LAS Scheduler was not

downloaded to the Backup LAS

device

Ensure that all of the devices that are intended to be a Backup LAS are

marked to receive the LAS schedule

All devices go off live

list and then return

Live list must be reconstructed by

Backup LAS device

Current link setting and configured links settings are different. Set the current

link setting equal to the configured settings.

Symptom Possible Causes Corrective Action

Mode will not leave

OOS

Target mode not set Set target mode to something other than OOS.

Memory Failure, Communication

Failure, Body Temperature

Failure

BLOCK_ERR will show the lost NV Data or Lost Static Data bit set. Restart the

device by setting RESTART to Processor. If the block error does not clear, call

the factory.

No I/O Power Ensure power at I/O Power Terminals are between 9-32 VDC.

Block Alarms Will not

work

Features FEATURE_SEL does not have Alerts enabled. Enable the report bit.

Notification LIM_NOTIFY is not high enough. Set equal to MAX_NOTIFY.

Symptom Possible Causes Corrective Action

Mode will not leave

OOS

Target mode not set Set target mode to something other than OOS.

Resource block The actual mode of the Resource block is in OOS. See Resource Block

Diagnostics for corrective action.

i/O Transducer Block The actual mode of the Transducer Block is OOS, set it to Auto

Symptom Possible Causes Corrective Action

I/O Failure Open or shorted sensor Check sensor and wiring

Reference Manual

00809-0100-4696, Rev AA

September 2004

4-4

Rosemount 848L

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Appendix A Reference Data

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page A-1

Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . page A-5

Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page A-7

SPECIFICATIONS

Functional

Specifications

Inputs

8 Discrete Inputs suitable for NAMUR specification sensors, 9-32VDC

sourcing sensors or general switch inputs (dry contact)

NAMUR Sensors:

On state: > 2.1 mA

Off state: < 1.2 mA

9-32 VDC Sourcing Sensors:

On state: > 50% of I/O voltage

Off state: < 20% of I/O voltage

General Switch Inputs:

On state: < 500 Ohms

Off state: > 5k Ohms

Minimum Pulse Width: 1ms

Maximum Pulse Input Frequency: 500Hz

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A-2

Outputs

4 Discrete Outputs

9-32 VDC loads

Maximum load inductance 300 mH

Current Ratings: 1.0 A maximum for single channel on, 4.0 A maximum per

device.

Output devices must be selected as follows:

1. Designed to use the same DC voltage as supplied to the 848L I/O

power terminals.

2. The DC resistance must be large enough that they consume no more

than 1 amp of current steady state. The internal impedance of the

848L is negligible, therefore the Output device’s current is simply

calculated as: I/O power / DC resistance.

3. The inductance of the output device must be less than 300 mH.

The maximum total output current for the device will depend on the ambient

temperature as shown in Figure A-1.

Figure A-1. Temperature vs.

Output Current

Thermal Shutdown Protection prevents damage to the device if temperature

specifications are exceeded.

Ambient Temperature (DegC)

Total Output Current (Amps)

2.0

1.5

1.0

3.5

2.5

0.5

50 55 60 65 70 75

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September 2004

A-3

Rosemount 848L

Isolation

Input-Output

1200 VDC; 600 V rms 50/60 Hz for dry

and 2-wire NAMUR contact inputs

No isolation when using 3-wire sensors

Input- Foundation Fieldbus

1200 VDC; 600 V rms 50/60 Hz

Output- Foundation Fieldbus

1200 VDC; 600 V rms 50/60 Hz

Input power- Foundation Fieldbus

1200 VDC; 600 V rms 50/60 Hz

Input / Output Power Requirements

24 VDC nominal, 9 VDC minimum, 32 VDC maximum

Supply Current Rating 0.5 amps at 24 VDC plus output load

Fieldbus Segment Power

Powered over the H1 Foundation fieldbus with standard fieldbus power

supplies. The logic transmitter operates between 9.0 and 32.0 VDC at 22

milliamps.

Transient Protection (consult factory for availability)

The transient protector (option code T1) helps to prevent damage to the

transmitter from transients induced on the bus/power wiring by lightening,

welding, heavy electrical equipment, or switch gears. This option is installed

at the factory for the Model 848L and is not intended for field installation.

ASME B 16.5 (ANSI)/IEEE C62.41-1991

(IEEE 587), Location Categories A2, B3.

1 kV peak (10 x 1000 S Wave)

6 kV / 3 kA peak (1.2 x 50 S Wave 8 x 20 S Combination Wave)

6 kV / 0.5 kA peak (100 kHz Ring Wave)

4 kV peak EFT (5 x 50 nS Electrical Fast Transient)

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Rosemount 848L

A-4

Physical Specifications Environmental Ratings

Electronics (no enclosure)

-40°C to +85°C

99% non-condensing humidity

IP20

Unit (electronics and enclosure)

-40°C to +85°C

100% condensing humidity

IP66

Function Blocks

Specification

H1 Segment Device

Back-up LAS

Resource Block

I/O Transducer Block

All inputs can optionally be latched for the duration necessary for each input

to be read during a macrocycle

Logic Transducer Block (20 Boolean Equations)

The processing cycle of the 848L logic equations from sampling the inputs to

driving the outputs will vary depending upon the number and type of functions

used in the 20 equations. Processing time can vary in the range of 50 to

150ms.

Logic Functions

AND, OR, XOR, NOT

Rising Edge Trigger

Falling Edge Trigger

Turn On Delay

Turn Off Delay

Pulse Counter

Reset

Set Latch

Shift Register Right

Shift Register Left

Function Blocks

8 DI blocks, 4 DO blocks, 1 MDI block,

and 1 MDO block are provided.

Foundation Fieldbus:

• Links 25

•VCR 20

Reference Manual

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September 2004

A-5

Rosemount 848L

EXAMPLE FOR THE LOGIC EXECUTION:

This diagram shows motor starter logic with start and stop buttons and an

auxiliary contact which maintains current after the start button is pressed.

Which would translate to a Boolean equation of:

AND(IN(1),OR(IN(2),IN(3)))

DIMENSIONAL

DRAWINGS

Figure A-2. Rosemount 848L

Dimensional Drawings

MOTOR_STARTER_LOGIC.TIF

Top View 3-D View

Front View Side View

6.7 (170)

3.7 (93)

848/848L/848L_06_AA, 848L_07_AA, 848L_08_AA, 848L_09_AA.EPS

1.7 (43)

Ground

Screw

Input Input Output Power

Connector

Dimensions are in inches (millimeters)

Reference Manual

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September 2004

Rosemount 848L

A-6

Figure A-3. Rosemount 848L

Wiring Diagram

848/848L/848L_10_AA, 848L_11_AA, 848L_12_AA, 848L_13_AA, 848L_14_AA.EPS

DISCRETE INPUT WIRING CONFIGURATION

2-Wire NAMUR Sensors

1 of 2 Input Connectors Dry Contact Switches

1 of 2 Input Connectors

3-Wire NAMUR Sensors

1 of 2 Input Connectors

9-32 VDC Sensors

1 of 2 Input Connectors

DISCRETE OUTPUT WIRING CONFIGURATION

9-32 VDC Outputs

Reference Manual

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September 2004

A-7

Rosemount 848L

ORDERING

INFORMATION

Model Product Description (Includes One Fieldbus H1 Segment)

848L Fieldbus Logic Transmitter

Code Communications Protocol

F FOUNDATION™ fieldbus digital signal

(includes 8 DI, 4 DO, 1 MDI, and 1 MDO function blocks, and Backup Link Active Scheduler)

Code Power Input

ABus and I/O Power (4-wire)

Code Product Certifications

Rosemount Junction

Box required?

NA No Approval No

N1 CENELEC ATEX Type n (enclosure required) Yes

NC CENELEC ATEX Type n Component No(1)

ND CENELEC ATEX Dust Ignition Proof Yes

N5 FM Non-Incendive for Class 1, Division 2, Groups A, B, C, D Yes

N6 CSA Non-Incendive for Class 1, Division 2, Groups A, B, C, D Yes

N7 IECEx Type n Approval (consult factory for availability) (enclosure required)

Code Discrete Inputs and Outputs Types

S001 8 - Dry Contact Inputs / 4 - 9 to 32 VDC Outputs

S002 8 - 2-wire NAMUR Sensor Inputs / 4 - 9 to 32 VDC Outputs

S003 8 - 3-wire NAMUR Sensor Inputs / 4 - 9 to 32 VDC Outputs

S004 8 - 9 to 32 VDC Inputs / 4 - 9 to 32 VDC Outputs

Code Options

Transient Protection

T1 Transient Protection (Consult factory for availability)

Mounting Kit Options

B6 Mounting Kit to a 2 in. pipe

Non Explosion-Proof Junction Box Options

JP1 Plastic Junction Box; No Entries

JP2 Plastic Junction Box; Cable Glands (9 X M20 nickel-plated brass glands for 7.5-11.9 mm unarmored cable)

JP3 Plastic Junction Box; Conduit Entries (5 Plugged Holes, suitable for installing 1/2-in. NPT fittings)

JA1 Aluminum Junction Box; No Entries

JA2 Aluminum Cable Glands (9 X M20 nickel-plated brass glands for 7.5-11.9 mm unarmored cable)

JA3 Aluminum Conduit Entries (5 Plugged Holes, suitable for installing 1/2-in. NPT fittings)

JS1 Stainless Steel Junction Box; No Entries

JS2 SST Box; Cable Glands (9 X M20 nickel-plated brass glands for 7.5-11.9 mm unarmored cable)

JS3 Stainless Steel Box, Conduit Entries (5 Plugged Holes, suitable for installing 1/2-in. NPT fittings)

Conduit Electrical Connector

GE(2) M12, 4-pin, Male Connector (eurofast®)

GM(2) A size Mini, 4-pin, Male Connector (minifast®)

Software Options

CT Disable Local Logic Function

Typical Model Number: 848L F A NA S001 T1 JP1

(1) The Rosemount 848L ordered with option code NC is not approved as a stand-alone unit. Additional system certification is required.

(2) Not available with certain hazardous location certifications. Contact a Rosemount representative for details.

Reference Manual

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September 2004

Rosemount 848L

A-8

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Appendix B Product Certifications

Approved Manufacturing Locations . . . . . . . . . . . . . . . . . page B-1

European Directive Information . . . . . . . . . . . . . . . . . . . . page B-1

Hazardous Locations Certificates . . . . . . . . . . . . . . . . . . . page B-1

APPROVED

MANUFACTURING

LOCATIONS

Rosemount Inc. — Chanhassen, Minnesota USA

Emerson Process Management Asia Pacific

Private Limited — Singapore

Rosemount Temperature GmbH - Karlstein, Germany

EUROPEAN DIRECTIVE

INFORMATION

The EC declaration of conformity for all applicable European directives for this

product can be found on the Rosemount website at www.rosemount.com. A

hard copy may be obtained by contacting our local sales office.

HAZARDOUS

LOCATIONS

CERTIFICATES

North American

Approvals

Factory Mutual (FM) Approvals

N5 Nonincendive for Class I, Division 2, Groups A, B, C, D

when installed per Rosemount drawing 00848-1035.

Temperature code: T4 (Tamb = –40°C to 60°C)

Canadian Standards Association (CSA) Approvals

N6 Suitable for Class I, Division 2, Groups A, B, C, D

when installed per Rosemount drawing 00848-1036.

Temperature code: T4 (Tamb = –40°C to 60°C)

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Rosemount 848L

B-2

European Approvals CENELEC Approvals

N1 CENELEC Type n

Certification Number: Baseefa04ATEX0027X

ATEX Marking II 3 G

EEx nA nL IIC T4 (Tamb = –40°C to 50°C)

Power/Bus

Max Supply Voltage = 32.0 V

Special Conditions for Safe Use (x):

1. The ambient temperature range of use shall be the most restrictive of

the apparatus, cable gland or blanking plug.

2. The apparatus is not capable of withstanding the 500V insulation test

required by Clause 9.4 of EN 50021:1999 or Clause 8.1 of EN

60079:2003. This must be taken into account when installing the

apparatus.

3. Component approved EEx e cable entries must be used so as to

maintain the ingress protection of the enclosure to at least IP54.

4. Any unused cable entry holes must be filled with component

approved EEx e blanking plugs.

NC CENELEC Type n Component

Certification Number: Baseefa04ATEX0026U

ATEX Marking II 3 G

EEx nA nL IIC T4 (Tamb = -40°C to 50°C)

Special Conditions for Safe Use (x):

1. The component must be installed in a suitable certified enclosure

capable of withstanding an impact of 7.0J.

2. The apparatus is not capable of withstanding the 500V insulation test

required by Clause 9.4 of EN 50021:1999 or Clause 8.1 of EN

60079:2003. This must be taken into account when installing the

apparatus.

ND CENELEC Dust Ignition Proof

Certification Number: Baseefa04ATEX0028X

ATEX Marking II 1 D

T90°C (Tamb = – 20°C to 65°C)

1180

Special Conditions for Safe Use (x):

1. Component approved EEx e cable entries must be used so as to

maintain the ingress protection of the enclosure to at least IP66.

2. Any unused cable entry hole must be filled with component approved

EEx e blanking plugs.

3. The ambient temperature range of use shall be the most restrictive of

the apparatus, cable gland or blanking plug.

Reference Manual

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September 2004 Rosemount 848L

www.rosemount.com

Appendix C Function Blocks

Resource Block Parameters . . . . . . . . . . . . . . . . . . . . . . . page C-1

I/O Transducer Parameters . . . . . . . . . . . . . . . . . . . . . . . . page C-5

Logic Transducer Parameters . . . . . . . . . . . . . . . . . . . . . . page C-8

Discrete Input Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page C-9

Discrete Output Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . page C-11

Multiple Discrete Input Blocks . . . . . . . . . . . . . . . . . . . . . page C-12

Multiple Discrete Output Block . . . . . . . . . . . . . . . . . . . . . page C-13

RESOURCE BLOCK

PARAMETERS

Table C-1. Resource Block Parameters

Number Parameter Description

1 ST_ REV The revision level of the static data associated with the function block.

2TAG_ DESC The user description of the intended application of the block.

3 STRATEGY The strategy field can be used to identify grouping of blocks.

4ALERT_ KEY The identification number of the plant unit.

5 MODE_ BLK The actual, target, permitted, and normal modes of the block. For further description, see the Mode

parameter formal model in FF-890.

6BLOCK_ ERR This parameter reflects the error status associated with the hardware or software components associated

with a block. Multiple errors may be shown. For a list of enumeration values, see FF-890, Block_ Err

formal model.

7 RS_ STATE State of the function block application state machine. For a list of enumeration values, see FF-890.

8TEST_ RW Read/write test parameter - used only for conformance testing.

9 DD_ RESOURCE String identifying the tag of the resource which contains the Device Description for the resource.

10 MANUFAC_ ID Manufacturer identification number - used by an interface device to locate the DD file for the resource.

11 DEV_ TYPE Manufacturer's model number associated with the resource - used by interface devices to locate the DD

file for the resource.

12 DEV_ REV Manufacturer revision number associated with the resource - used by an interface device to locate the DD

file for the resource.

13 DD_ REV Revision of the DD associated with the resource - used by the interface device to locate the DD file for the

resource.

14 GRANT_ DENY Options for controlling access of host computer and local control panels to operating, tuning and alarm

parameters of the block.

15 HARD_ TYPES The types of hardware available as channel numbers. The supported hardware type is: SCALAR_ INPUT

16 RESTART Allows a manual restart to be initiated.

17 FEATURES Used to show supported resource block options. The supported features are: SOFT_ WRITE_ LOCK_

SUPPORT, HARD_ WRITE_ LOCK_ SUPPORT, REPORTS, and UNICODE

18 FEATURE_ SEL Used to select resource block options.

19 CYCLE_ TYPE Identifies the block execution methods available for this resource. The supported cycle types are:

SCHEDULED, and COMPLETION_ OF_ BLOCK_ EXECUTION

20 CYCLE_ SEL Used to select the block execution method for this resource.

21 MIN_ CYCLE_T Time duration of the shortest cycle interval of which the resource is capable.

22 MEMORY_ SIZE Available configuration memory in the empty resource. To be checked before attempting a download.

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C-2

23 NV_ CYCLE_T Minimum time interval specified by the manufacturer for writing copies of NV parameters to non-volatile

memory. Zero means it will never be automatically copied. At the end of NV_ CYCLE_T, only those

parameters which have changed need to be updated in NVRAM.

24 FREE_ SPACE Percent of memory available for further configuration. Zero in preconfigured resource.

25 FREE_ TIME Percent of the block processing time that is free to process additional blocks.

26 SHED_ RCAS Time duration at which to give up on computer writes to function block RCas locations. Shed from RCas

will never happen when SHED_ RCAS = 0.

27 SHED_ ROUT Time duration at which to give up on computer writes to function block ROut locations. Shed from ROut will

never happen when SHED_ ROUT = 0.

28 FAULT_ STATE Condition set by loss of communication to an output block, fault promoted to an output block or physical

contact. When FAULT_ STATE condition is set, then output function blocks will perform their FAULT_

STATE actions.

29 SET_ FSTATE Allows the FAULT_ STATE condition to be manually initiated by selecting Set.

30 CLR_ FSTATE Writing a Clear to this parameter will clear the device FAULT_ STATE if the field condition has cleared.

31 MAX_ NOTIFY Maximum number of unconfirmed notify messages possible.

32 LIM_ NOTIFY Maximum number of unconfirmed alert notify messages allowed.

33 CONFIRM_ TIME The time the resource will wait for confirmation of receipt of a report before trying again. Retry will not

happen when CONFIRM_ TIME = 0.

34 WRITE_ LOCK If set, no writes from anywhere are allowed, except to clear WRITE_ LOCK. Block inputs will continue to

be updated.

35 UPDATE_ EVT This alert is generated by any change to the static data.

36 BLOCK_ ALM The BLOCK_ ALM is used for all configuration, hardware, connection failure or system problems in the

block. The cause of the alert is entered in the subcode field. The first alert to become active will set the

Active status in the Status attribute. As soon as the Unreported status is cleared by the alert reporting task,

another block alert may be reported without clearing the Active status, if the subcode has changed.

37 ALARM_ SUM The current alert status, unacknowledged states, unreported states, and disabled states of the alarms

associated with the function block.

38 ACK_ OPTION Selection of whether alarms associated with the block will be automatically acknowledged.

39 WRITE_ PRI Priority of the alarm generated by clearing the write lock.

40 WRITE_ ALM This alert is generated if the write lock parameter is cleared.

41 ITK_ VER Major revision number of the interoperability test case used in certifying this device as interoperable. The

format and range are controlled by the Fieldbus Foundation.

42 DISTRIBUTOR Reserved for use as distributor ID. No Foundation enumerations defined at this time.

43 DEV_STRING This is used to load new licensing into the device. The value can be written but will always read back with

a value of 0.

44 XD_ OPTIONS Indicates which transducer block licensing options are enabled.

45 FB_ OPTIONS Indicates which function block licensing options are enabled.

46 DIAG_ OPTIONS Indicates which diagnostics licensing options are enabled.

47 MISC_ OPTIONS Indicates which miscellaneous licensing options are enabled.

48 RB_ SFTWR_

REV_ MAJOR

Major revision of software that the resource block was created with.

49 RB_ SFTWR_

REV_ MINOR

Minor revision of software that the resource block was created with.

50 RB_ SFTWR_

REV_ BUILD

Build of software that the resource block was created with.

51 RB_SFTWR_REV_

ALL

The string contains the following fields:

Major rev: 1-3 characters, decimal number 0-255

Minor rev: 1-3 characters, decimal number 0-255

Build rev: 1-3 characters, decimal number 0-255

Time of build: 8 characters, xx:xx:xx, military time

Day of week of build: 3 characters, Sun, Mon,

Month of build: 3 characters, Jan, Feb.

Day of month of build: 1-2 characters, decimal number 1-31

Year of build: 4 characters, decimal

Builder: 7 characters, login name of builder

52 HARDWARE_ REV Hardware revision of that hardware that has the resource block in it.

Table C-1. Resource Block Parameters

Number Parameter Description

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Rosemount 848L

53 OUTPUT_

BOARD_ SN

Output board serial number.

54 FINAL_ ASSY_

NUM

The same final assembly number specified or set by the customer.

55 DETAILED_

STATUS

Indicates the state of the transmitter.

56 SUMMARY_

STATUS

An enumerated value of repair analysis.

57 MESSAGE_ DATE Date associated with the MESSAGE_ TEXT parameter

58 MESSAGE_ TEXT Used to indicate changes made by the user to the device installation, configuration, or calibration.

59 SELF_ TEST Used to self test the device. Tests are device specific.

60 DEFINE_ WRITE_

LOCK

Allows the operator to select how WRITE_ LOCK behaves. The initial value is "lock everything". If the

value is set to "lock only physical device" then the resource and transducer blocks of the device will be

locked but changes to function blocks will be allowed.

61 SAVE_ CONFIG_

NOW

Allows the user to optionally save all non-volatile information immediately.

62 SAVE_ CONFIG_

BLOCKS

Number of EEPROM blocks that have been modified since last burn. This value will count down to zero

when the configuration is saved.

63 START_ WITH_

DEFAULTS

0 = Uninitialized

1 = do not power-up with NV defaults

2 = power-up with default node address

3 = power-up with default pd_ tag and node address

4 = power-up with default data for the entire communications stack (no application data)

64 SIMULATE_ IO Status of Simulate jumper/switch

65 SECURITY_ IO Status of Security jumper/switch

66 SIMULATE_ STATE The state of the simulate jumper

0 = Uninitialized

1 = Jumper/switch off, simulation not allowed

2 = Jumper/switch on, simulation not allowed (need to cycle jumper/switch)

3 = Jumper/switch on, simulation allowed

67 DOWNLOAD_

MODE

Gives access to the boot block code for over the wire downloads

0 = Uninitialized

1 = Run Mode

2 = Download Mode

68 RECOMMENDED_

ACTION

Enumerated list of recommended actions displayed with a device alert.

69 FAILED_ PRI Designates the alarming priority of the FAILED_ ALM.

70 FAILED_ ENABLE Enabled FAILED_ ALM alarm conditions. Corresponds bit for bit to the FAILED_ ACTIVE. A bit on means

that the corresponding alarm condition is enabled and will be detected. A bit off means the corresponding

alarm condition is disabled and will not be detected.

71 FAILED_ MASK Mask of FAILED_ ALM. Corresponds bit for bit to FAILED_ ACTIVE. A bit on means that the condition is

masked out from alarming.

72 FAILED_ ACTIVE Enumerated list of failure conditions within a device.

73 FAILED_ ALM Alarm indicating a failure within a device which makes the device non-operational.

74 MAINT_ PRI Designates the alarming priority of the MAINT_ ALM

75 MAINT_ ENABLE Enabled MAINT_ ALM alarm conditions. Corresponds bit for bit to the MAINT_ ACTIVE. A bit on means

that the corresponding alarm condition is enabled and will be detected. A bit off means the corresponding

alarm condition is disabled and will not be detected.

76 MAINT_ MASK Mask of MAINT_ ALM. Corresponds bit for bit to MAINT_ ACTIVE. A bit on means that the condition is

masked out from alarming.

77 MAINT_ ACTIVE Enumerated list of maintenance conditions within a device.

78 MAINT_ ALM Alarm indicating the device needs maintenance soon. If the condition is ignored, the device will eventually

fail.

79 ADVISE_ PRI Designates the alarming priority of the ADVISE_ ALM

Table C-1. Resource Block Parameters

Number Parameter Description

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C-4

80 ADVISE_ ENABLE Enabled ADVISE_ ALM alarm conditions. Corresponds bit for bit to ADVISE_ ACTIVE. A bit on means that

the corresponding alarm condition is enabled and will be detected. A bit off means the corresponding

alarm condition is disabled and will not be detected.

81 ADVISE_ MASK Mask of ADVISE_ ALM. Corresponds bit for bit to ADVISE_ ACTIVE. A bit on means that the condition is

masked out from alarming.

82 ADVISE_ ACTIVE Enumerated list of advisory conditions within a device.

83 HEALTH_ INDEX Alarm indicating advisory alarms. These conditions do not have a direct impact on the process or device

integrity.

84 PWA_ SIMULATE Parameter representing the overall health of the device, 100 being perfect and 1 being non-functioning.

The value will be set based on the active PWA alarms in accordance with the requirements stated in

"Device Alerts and Health Index PlantWeb Implementation Rules". Each device may implement its own

unique mapping between the PWA parameters and HEALTH_ INDEX although a default mapping will be

available based on the following rules.

HEALTH_ INDEX will be set based on the highest priority PWA *_ ACTIVE bit as follows:

FAILED_ ACTIVE: 0 to 31 - HEALTH_ INDEX = 10

MAINT_ ACTIVE: 27 to 31 - HEALTH_ INDEX = 20

MAINT_ ACTIVE: 22 to 26 - HEALTH_ INDEX = 30

MAINT_ ACTIVE: 16 to 21 - HEALTH_ INDEX = 40

MAINT_ ACTIVE: 10 to 15 - HEALTH_ INDEX = 50

MAINT_ ACTIVE: 5 to 9 - HEALTH_ INDEX = 60

MAINT_ ACTIVE: 0 to 4 - HEALTH_ INDEX = 70

ADVISE_ ACTIVE: 16 to 31 - HEALTH_ INDEX = 80

ADVISE_ ACTIVE: 0 to 15 - HEALTH_ INDEX = 90

NONE - HEALTH_ INDEX = 100

85 ADVISE_ ACTIVE Allows direct writes to the PlantWeb Alert "ACTIVE" parameters and RB.DETAILED_STATUS. The

simulate switch must be "ON' and the SIMULATE_STATE must be "Switch on, simulation allowed" before

PWA_SIMULATE can be active.

Table C-1. Resource Block Parameters

Number Parameter Description

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Rosemount 848L

I/O TRANSDUCER

PARAMETERS

Table C-2. I/O Transducer Parameters

Numbe

rParameter Description

1 ST_ REV The revision level of the static data associated with the function block.

2TAG_ DESC The user description of the intended application of the block.

3 STRATEGY The strategy field can be used to identify grouping of blocks.

4ALERT_ KEY The identification number of the plant unit.

5 MODE_ BLK The actual, target, permitted, and normal modes of the block. For further description, see the Mode

parameter formal model in FF-890.

6BLOCK_ ERR This parameter reflects the error status associated with the hardware or software components

associated with a block. Multiple errors may be shown. For a list of enumeration values, see FF-890,

Block_ Err formal model.

7 UPDATE_ EVT This alert is generated by any change to the static data.

8BLOCK_ ALM The block alarm is used for all configuration, hardware, connection failure, or system problems in the

block. The cause of the alert is entered in the subcode field. The first alert to become active will set the

Active status in the Status attribute. As soon as the Unreported status is cleared by the alert reporting

task, another block alert may be reported without clearing the Active status, if the subcode has

changed.

9 TRANSDUCER_

DIRECTORY

A directory that specifies the number and starting indices of the transducers in the transducer block. For

further information, please refer to the Transducer Block Application Process - Part 1 (FF-902)

specification.

10 TRANSDUCER_ TYPE Identifies the transducer that follows.

11 XD_ ERROR One of the error codes defined in FF-903 XD_ ERROR and Block Alarm Subcodes.

12 COLLECTION_

DIRECTORY

A directory that specifies the number, starting indices, and DD item IDs of the data collections in each

transducer within a transducer block. For further information, please refer FF-902.

13 IN_ 1_ TAG An identifier associated with discrete input 1.

14 IN1 The value and status of discrete input 1.

15 PULSE_ COUNT_ 1 The number of pulses that have occurred on IN1 since last reset.

16 IN_ 1_ CONFIG.IO_TYPE The transducer type of discrete sensor 1.

16 IN_ 1_ CONFIG.FILTER Any state change on IN1 that lasts for a duration less than this filter value, will be ignored by the device.

16 IN_ 1_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO1 will have its value set to this value.

17 IN_ 2_ TAG An identifier associated with discrete input 2.

18 IN2 The value and status of discrete input 2.

19 PULSE_ COUNT_ 2 The number of pulses that have occurred on IN2 since last reset.

20 IN_ 2_ CONFIG.IO_TYPE The transducer type of discrete sensor 2.

20 IN_ 2_ CONFIG.FILTER Any state change on IN2 that lasts for a duration less than this filter value, will be ignored by the device.

20 IN_ 2_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO2 will have its value set to this value.

21 IN_ 3_ TAG An identifier associated with discrete input 3.

22 IN3 The value and status of discrete input 3.

23 PULSE_ COUNT_ 3 The number of pulses that have occurred on IN3 since last reset.

24 IN_ 3_ CONFIG.IO_TYPE The transducer type of discrete sensor 3.

24 IN_ 3_ CONFIG.FILTER Any state change on IN3 that lasts for a duration less than this filter value, will be ignored by the device.

24 IN_ 3_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO3 will have its value set to this value.

25 IN_ 4_ TAG An identifier associated with discrete input 4.

26 IN4 The value and status of discrete input 4.

27 PULSE_ COUNT_ 4 The number of pulses that have occurred on IN4 since last reset.

28 IN_ 4_ CONFIG.IO_TYPE The transducer type of discrete sensor 4.

28 IN_ 4_ CONFIG.FILTER Any state change on IN4 that lasts for a duration less than this filter value, will be ignored by the device.

28 IN_ 4_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO4 will have its value set to this value.

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C-6

29 TRANSDUCER_ TYPE_

Identifies the transducer that follows.

30 XD_ ERROR_ 2 One of the error codes defined in FF-903 XD_ ERROR and Block Alarm Subcodes.

31 COLLECTION_

DIRECTORY_ 2

A directory that specifies the number, starting indices, and DD item IDs of the data collections in each

transducer within a transducer block. For further information, please refer FF-902.

32 IN_ 5_ TAG An identifier associated with discrete input 5.

33 IN5 The value and status of discrete input 5.

34 PULSE_ COUNT_ 5 The number of pulses that have occurred on IN5 since last reset.

35 IN_ 5_ CONFIG.IO_TYPE The transducer type of discrete sensor 5.

35 IN_ 5_ CONFIG.FILTER Any state change on IN5 that lasts for a duration less than this filter value, will be ignored by the device.

35 IN_ 5_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO5 will have its value set to this value.

36 IN_ 6_ TAG An identifier associated with discrete input 6.

37 IN6 The value and status of discrete input 6.

38 PULSE_ COUNT_ 6 The number of pulses that have occurred on IN6 since last reset.

39 IN_ 6_ CONFIG.IO_TYPE The transducer type of discrete sensor 6.

39 IN_ 6_ CONFIG.FILTER Any state change on IN6 that lasts for a duration less than this filter value, will be ignored by the device.

39 IN_ 6_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO6 will have its value set to this value.

40 IN_ 7_ TAG An identifier associated with discrete input 7.

41 IN7 The value and status of discrete input 7.

42 PULSE_ COUNT_ 7 The number of pulses that have occurred on IN7 since last reset.

43 IN_ 7_ CONFIG.IO_TYPE The transducer type of discrete sensor 7.

43 IN_ 7_ CONFIG.FILTER Any state change on IN7 that lasts for a duration less than this filter value, will be ignored by the device.

43 IN_ 7_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO7 will have its value set to this value.

44 IN_ 8_ TAG An identifier associated with discrete input 8.

45 IN8 The value and status of discrete input 8.

46 PULSE_ COUNT_ 8 The number of pulses that have occurred on IN8 since last reset.

47 IN_ 8_ CONFIG.IO_TYPE The transducer type of discrete sensor 8.

47 IN_ 8_ CONFIG.FILTER Any state change on IN8 that lasts for a duration less than this filter value, will be ignored by the device.

47 IN_ 8_ CONFIG.FAIL_

SAFE

When the device detects a failure, IO8 will have its value set to this value.

48 TRANSDUCER_ TYPE_

Identifies the transducer that follows.

49 XD_ ERROR_ 3 One of the error codes defined in FF-903 XD_ ERROR and Block Alarm Subcodes.

50 COLLECTION_

DIRECTORY_ 3

A directory that specifies the number, starting indices, and DD item IDs of the data collections in each

transducer within a transducer block. For further information, please refer FF-902.

51 OUT_ 1_ TAG An identifier associated with discrete output 1.

52 OUT1 The value and status of discrete Output 1.

53 OUT_ 1_

CONFIG.IO_TYPE

The transducer type of discrete sensor 9.

53 OUT_ 1_

CONFIG.FILTER

Any state change that lasts for a duration less than this filter value, will be ignored by the device.

53 OUT_ 1_ CONFIG.FAIL_

SAFE

When the device detects a failure, OUT1 will be set to this value.

54 OUT_ 2_ TAG An identifier associated with discrete output 2.

55 OUT2 The value and status of discrete Output 2.

56 OUT_2_CONFIG.IO_TYP

The transducer type of discrete sensor 10.

56 OUT_ 2_

CONFIG.FILTER

Any state change that lasts for a duration less than this filter value, will be ignored by the device.

56 OUT_2_CONFIG.FAIL_

SAFE

When the device detects a failure, OUT2 will be set to this value.

Table C-2. I/O Transducer Parameters

Numbe

rParameter Description

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Rosemount 848L

57 OUT_ 3_ TAG An identifier associated with discrete output 3.

58 OUT3 The value and status of discrete Output 3.

59 OUT_ 3_

CONFIG.IO_TYPE

The transducer type of discrete sensor 11.

59 OUT_3_CONFIG.FILTER Any state change that lasts for a duration less than this filter value, will be ignored by the device.

59 OUT_3_CONFIG.FAIL_S

AFE

When the device detects a failure, OUT3 will be set to this value.

60 OUT_ 4_TAG An identifier associated with discrete output 4.

61 OUT4 The value and status of discrete Output 4.

62 OUT_ 4_

CONFIG.IO_TYPE

The transducer type of discrete sensor 12.

62 OUT_ 4_

CONFIG.FILTER

Any state change that lasts for a duration less than this filter value, will be ignored by the device.

62 OUT_ 4_ CONFIG.FAIL_

SAFE

When the device detects a failure, OUT4 will be set to this value.

63 BODY_ TEMP The value and status of electronics temperature.

64 IO_ SOFT_ REV The string contains the following fields: Major rev: 1-3 characters, decimal number 0-255 Minor rev: 1-3

characters, decimal number 0-255Build rev: 1-3 characters, decimal number 0-255 Time of build: 8

characters, xx:xx:xx, military time Day of week of build: 3 characters, Sun, Mon, Month of build: 3

characters, Jan, Feb. Day of month of build: 1-2 characters, decimal number 1-31 Year of build: 4

characters, decimal Builder: 7 characters, login name of builder

65 CLEAR_COUNTS Each bit can be written to in order to reset PULSE_ COUNT_ X. The bits numbered from 1 (LSB) to

8(MSB) will reset PULSE_ COUNT_ 1 to PULSE_ COUNT_ 8 respectively.

66 DETAILED_ STATUS Indicates the state of the transmitter.

67 MACRO_ IN_ LATCH Allows transitions of transducer block channels to be held in a specified state until the macrocycle reads

the value at least once.

68 MACRO_ EQ_ LATCH Allows transitions of transducer block channels to be held in a specified state until the macrocycle reads

the value at least once.

69 MACRO_ OUT_ LATCH Allows transitions of transducer block channels to be held in a specified state until the macrocycle reads

the value at least once.

Table C-2. I/O Transducer Parameters

Numbe

rParameter Description

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C-8

LOGIC TRANSDUCER

PARAMETERS

Table C-3. Logic Transducer Parameters and Descriptions

Number Parameter Description

1 ST_ REV The revision level of the static data associated with the function block.

2TAG_ DESC The user description of the intended application of the block.

3 STRATEGY The strategy field can be used to identify grouping of blocks.

4ALERT_ KEY The identification number of the plant unit.

5 MODE_ BLK The actual, target, permitted, and normal modes of the block. For further description, see the Mode

parameter formal model in FF-890.

6BLOCK_ ERR This parameter reflects the error status associated with the hardware or software components associated

with a block. Multiple errors may be shown. For a list of enumeration values, see FF-890, Block_ Err

formal model.

7 UPDATE_ EVT This alert is generated by any change to the static data.

8BLOCK_ ALM The block alarm is used for all configuration, hardware, connection failure, or system problems in the

block. The cause of the alert is entered in the subcode field. The first alert to become active will set the

Active status in the Status attribute. As soon as the Unreported status is cleared by the alert reporting task,

another block alert may be reported without clearing the Active status, if the subcode has changed.

9 TRANSDUCER_

DIRECTORY

A directory that specifies the number and starting indices of the transducers in the transducer block. For

further information, please refer to the Transducer Block Application Process - Part 1 (FF-902)

specification.

10 TRANSDUCER_

TYPE

Identifies the transducer that follows.

11 XD_ ERROR One of the error codes defined in FF-903 XD_ ERROR and Block Alarm Subcodes.

12 COLLECTION_

DIRECTORY

A directory that specifies the number, starting indices, and DD item IDs of the data collections in each

transducer within a transducer block. For further information, please refer FF-902.

13 EQ1 A boolean equation used to define the computation of EQ1_ VALUE.

14 EQ2 A boolean equation used to define the computation of EQ2_ VALUE.

15 EQ3 A boolean equation used to define the computation of EQ3_ VALUE.

16 EQ4 A boolean equation used to define the computation of EQ4_ VALUE.

17 EQ5 A boolean equation used to define the computation of EQ5_ VALUE.

18 EQ6 A boolean equation used to define the computation of EQ6_ VALUE.

19 EQ7 A boolean equation used to define the computation of EQ7_ VALUE.

20 EQ8 A boolean equation used to define the computation of EQ8_ VALUE.

21 EQ9 A boolean equation used to define the computation of EQ9_ VALUE.

22 EQ10 A boolean equation used to define the computation of EQ10_ VALUE.

23 EQ11 A boolean equation used to define the computation of EQ11_ VALUE.

24 EQ12 A boolean equation used to define the computation of EQ12_ VALUE.

25 EQ13 A boolean equation used to define the computation of EQ13_ VALUE.

26 EQ14 A boolean equation used to define the computation of EQ14_ VALUE.

27 EQ15 A boolean equation used to define the computation of EQ15_ VALUE.

28 EQ16 A boolean equation used to define the computation of EQ16_ VALUE.

29 OUT1_ EQ A boolean equation used to define the computation of OUT1_ VALUE.

30 OUT2_ EQ A boolean equation used to define the computation of OUT2_ VALUE.

31 OUT3_ EQ A boolean equation used to define the computation of OUT3_ VALUE.

32 OUT4_ EQ A boolean equation used to define the computation of OUT4_ VALUE.

33 PARSE_ RESULT A feedback string that displays the result of parsing EQ1 - EQ16, and OUT1_ EQ - OUT4_ EQ.

34 EQ1_ VALUE The value and status of the result of computing EQ1.

35 EQ2_ VALUE The value and status of the result of computing EQ2.

36 EQ3_ VALUE The value and status of the result of computing EQ3.

37 EQ4_ VALUE The value and status of the result of computing EQ4.

38 EQ5_ VALUE The value and status of the result of computing EQ5.

39 EQ6_ VALUE The value and status of the result of computing EQ6.

40 EQ7_ VALUE The value and status of the result of computing EQ7.

41 EQ8_ VALUE The value and status of the result of computing EQ8.

42 EQ9_ VALUE The value and status of the result of computing EQ9.

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Rosemount 848L

DISCRETE INPUT

BLOCK

The DI takes the manufacturer’s discrete input data, selected by channel

number, and makes it available to other function blocks as its output. The

output will have a value of either true or false along with the status of the

output. A custom feature of the DI block in the 848L is the ability to pack 8

status bits into the single output of a DI block. This is accomplished by

selecting the appropriate channel number for packed data. This feature is

used in custom applications implemented in control systems such as DeltaV.

The DI block supports a function to invert the input and alarming.

43 EQ10_ VALUE The value and status of the result of computing EQ10.

44 EQ11_ VALUE The value and status of the result of computing EQ11.

45 EQ12_ VALUE The value and status of the result of computing EQ12.

46 EQ13_ VALUE The value and status of the result of computing EQ13.

47 EQ14_ VALUE The value and status of the result of computing EQ14.

48 EQ15_ VALUE The value and status of the result of computing EQ15.

49 EQ16_ VALUE The value and status of the result of computing EQ16.

50 OUT1_ VALUE The value and status of the result of computing OUT1_ EQ.

51 OUT2_ VALUE The value and status of the result of computing OUT2_ EQ.

52 OUT3_ VALUE The value and status of the result of computing OUT3_ EQ.

53 OUT4_ VALUE The value and status of the result of computing OUT4_ EQ.

54 DO1_ VALUE The value and status of value coming from channel DO1.

55 DO2_ VALUE The value and status of value coming from channel DO2.

56 DO3_ VALUE The value and status of value coming from channel DO3.

57 DO4_ VALUE The value and status of value coming from channel DO4.

58 DO5_ VALUE The value and status of value coming from channel DO5.

59 DO6_ VALUE The value and status of value coming from channel DO6.

60 DO7_ VALUE The value and status of value coming from channel DO7.

61 DO8_ VALUE The value and status of value coming from channel DO8.

62 DETAILED_

STATUS

Indicates the state of the transmitter.

Table C-3. Logic Transducer Parameters and Descriptions

Number Parameter Description

CHANNEL

MODE

Simulate

SIMULATE_D

Optional

Invert

Filter

PV_FTIME

PV_D

Output OUT_D

Alarms

DISC

FIELD_VAL_D

848/848L/DISCRETE1.EPS

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C-10

Table C-4. Parameters

Index Parameter

1ST_REV

2TAG_DESC

3STRATEGY

4ALERT_KEY

5 MODE_BLK

6BLOCK_ERR

7PV_D

8OUT_D

9 SIMULATE_D

10 XD_STATE

11 OUT_STATE

12 GRANT_DENY

13 IO_OPTS

14 STATUS_OPTS

15 CHANNEL

16 PV_FTIME

17 FIELD_VAL_D

18 UPDATE_EVT

19 BLOCK_ALM

20 ALARM_SUM

21 ACK_OPTION

22 DISC_PRI

23 DISC_LIM

24 DISC_ALM

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Rosemount 848L

DISCRETE OUTPUT

BLOCK The DO block makes the value sent in SP_D, CAS_IN_D, or RCAS_IN_D

available for processing by the device. The CHANNEL selection determines

where the value is stored in the 848L. A custom feature of the DO block in the

848L is the ability to accept 8 status bits packed into the single setpoint of a

DO block. This is accomplished by selecting the appropriate channel number

for packed data. This feature is used in custom applications implemented in

control systems such as DeltaV.

The Invert I/O option can be used to do a Boolean NOT function on the

setpoint value.

The SP_D supports the full cascade sub-function. Cas mode must be used to

transfer the output of another block to the SP_D of the DO.

There are additional I/O options which will cause the SP_D value to track the

PV_D value when the block is in an actual mode of LO or Man.

The 848L does not support a readback value in which case READBACK_D is

generated from OUT_D. The OUT_D and READBACK_D parameters both

use XD_STATE. The PV_D and SP_D use PV_STATE.

Supported Modes O/S, LO, Iman, Man, Auto, Cas, and RCas. The Man mode can be used to

force the output, in a PLC sense. It may be that Man mode is not permitted,

but it must be supported so that Man mode may be entered when leaving

O/S. The IMan mode is used to indicated that there is no path to the final

element. IMAN is not used in the 848L.

Setpoint Optional

Invert

Output

Simulate

SIMULATE_D CHANNEL

OUT_D

READBACK_D

PV_D

Fault State

FSTATE_TIME

FSTATE_VAL_D

SP_D

Optional

Invert

MODE

SHED_OPT

BKCAL_OUT_D

RCAS_OUT_D

CAS_IN_D

RCAS_IN_D

848/848L/DISCRETE2.EPS

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C-12

Table C-5. Parameters

MULTIPLE DISCRETE

INPUT BLOCKS

The MDI block makes available for the FF network eight discrete variables of

the I/O subsystem through its eight output parameters OUT_D1/8 Status

indication in the OUT_Dx output parameters depends on the I/O subsystem

and the transducer block, that is manufacturer specific.

For example, if there is individual detection of sensor failure, it can be

indicated in the status of related OUT_Dx parameter. A problem in the

interface to the I/O subsystem can be indicated in the status of all OUT_Dx as

BAD – Device Failure.

Index Parameter

1ST_REV

2TAG_DESC

3STRATEGY

4ALERT_KEY

5 MODE_BLK

6BLOCK_ERR

7PV_D

8SP_D

9OUT_D

10 SIMULATE_D

11 PV_STATE

12 XD_STATE

13 GRANT_DENY

14 IO_OPTS

15 STATUS_OPTS

16 READBACK_D

17 CAS_IN_D

18 CHANNEL

19 FSTATE_TIME

20 FSTATE_VAL_D

21 BKCAL_OUT_D

22 RCAS_OUT_D

23 SHED_OPT

24 RCAS_OUT_D

25 UPDATE_EVT

26 BLOCK_ALM

OUT_D1

OUT_D2

OUT_D3

OUT_D4

OUT_D5

OUT_D6

OUT_D7

OUT_D8

BLOCK

ALGORITHM

INPUT SNAP OF

TRANSDUCER

BLOCK OUTPUTS

CHANNEL

848/848L/DISCRETE3.EPS

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Rosemount 848L

Table C-6. Parameters and

Description

MULTIPLE DISCRETE

OUTPUT BLOCK

The MDO block makes available to the I/O subsystem its eight input

parameters IN_D1/8.

This function block keeps the fault state features specified for the DO block. It

includes option to hold the last value or a preset value when in Fault State,

individual preset values for each point, and a delay time to go into the Fault

State.

The actual mode will be LO only due to the resource block (SET_FSTATE

parameter). If an input parameter has a bad status, that parameter will be in

Fault State, but the mode calculation of the block will not be affected.

The parameter FSTATE_STATUS shows that points are in Fault State.

The MDO block does not support back calculation, or the Cas mode.

Index Parameter Description

1 ST_REV The revision level of the static data associated with the function block.

2TAG_DESC The user description of the intended application of the block.

3 STRATEGY The strategy field can be used to identify grouping of blocks.

4ALERT_KEY The identification number of the plant unit.

5 MODE_BLK The actual, target, permitted, and normal modes of the block:

Target: The mode to .go to.

Actual: The mode the .block is currently in.

Permitted: Allowed modes that target may take on

Normal: Most common mode for actual

6BLOCK_ERR This parameter reflects the error status associated with the hardware or software components

associated with a block. It is a bit string, so that multiple errors may be shown.

7 CHANNEL The CHANNEL value is used to select the measurement value. Refer to the appropriate device

manual for information about the specific channels available in each device. You must configure the

CHANNEL parameter before you can configure the XD_SCALE parameter.

8OUT_D1 Discrete output to indicate a selected alarm condition.

9 OUT_D2 Discrete output to indicate a selected alarm condition.

10 OUT_D3 Discrete output to indicate a selected alarm condition.

11 OUT_D4 Discrete output to indicate a selected alarm condition.

12 OUT_D5 Discrete output to indicate a selected alarm condition.

13 OUT_D6 Discrete output to indicate a selected alarm condition.

14 OUT_D7 Discrete output to indicate a selected alarm condition.

15 OUT_D8 Discrete output to indicate a selected alarm condition.

16 UPDATE_EVT This alert is generated by any change to the static data.

17 BLOCK_ALM The block alarm is used for all configuration, hardware, connection failure or system problems in the

block. The cause of the alert is entered in the subcode field. The first alert to become active will set the

Active status in the Status parameter. As soon as the Unreported status is cleared by the alert

reporting task, another block alert may be reported without clearing the Active status, if the subcode

has changed.

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C-14

Table C-7. Parameters and

Description

IN_D3

BLOCK

ALGORITHM CHANNEL

OUTPUT SNAP OF

TRANSDUCER

BLOCK INPUTS

IN_D4

IN_D5

IN_D6

IN_D7

IN_D8

IN_D1

IN_D2

848/848L/DISCRETE3.EPS

Index Parameter

1ST_REV

2TAG_DESC

3STRATEGY

4ALERT_KEY

5 MODE_BLK

6BLOCK_ERR

7 CHANNEL

8IN_D1

9IN_D2

10 IN_D3

11 IN_D4

12 IN_D5

13 IN_D6

14 IN_D7

15 IN_D8

16 MO_OPTS

17 FSTATE_TIME

18 FSTATE_VAL_D1

19 FSTATE_VAL_D2

20 FSTATE_VAL_D3

21 FSTATE_VAL_D4

22 FSTATE_VAL_D5

23 FSTATE_VAL_D6

24 FSTATE_VAL_D7

25 FSTATE_VAL_D8

26 FSTATE_STATUS

27 UPDATE_EVT

28 BLOCK_ALM

Reference Manual

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September 2004 Rosemount 848L

www.rosemount.com

Appendix D Logic Equation Syntax

Error Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page D-4

Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page D-5

1. All lines shall end with a semi-colon.

2. Accepted characters shall be standard 7-bit ASCII characters from

the list below:

•A-Z

•a-z

•0-9

• , (comma)

• ( ) (parenthesis)

• (space)

• ; (semicolon)

• _ (underscore)

3. The maximum number of characters per equation shall be 80.

4. Function calls are in the form FUNC(PARAM1,PARAM2,...PARAMN)

where FUNC is one of the supported functions in Table D-1 on

page D-2, and PARAMx are expressions to be input to the function.

5. Function names must be one of the names listed in the table below.

6. All spaces shall be ignored except within function names and function

parameters.

7. The parameters in a function call shall contain at least the required

parameters shown in table 2, but no more than the maximum.

8. The number of times a function is used (totaled in all equations) must

be less than or equal to the maximum number of instances allowed

shown in Table D-1 on page D-2.

9. Each equation must evaluate to a single boolean value.

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D-2

Table D-1. Supported Functions

Function Name

Required number

of parameters

Maximum number

of parameters Function Description

Maximum

Instances

AND 2 10 AND (a, b,...);

This function's result will be the logical and of a, b,...

NO LIMIT

CLOCK 2 2 CLOCK (onTime, offTime);

This function is a periodic clock. The result of this

function will be true for 'onTime' * 100 milliseconds,

then false for 'offTime' * 100 milliseconds, and repeats

forever.

CTU 3 3 CTU (clock, reset, count);

This function is an UP COUNTER. When 'reset' is true,

this function will set its' internal counter to 0. When

'reset' is false, this function will increment its' internal

counter each time 'clock' has a rising edge, until the

counter reaches 'count'. The result of this function will

be true when the counter reaches 'count', and false

otherwise.

DO 1 1 DO (channel number);

This function's result will be the value of the requested

external channel value coming into this device via a DO

function block.

NO LIMIT

EQ 1 1 EQ (channel number);

This function's result will be the value of the requested

equation result.

Note: The equation values are processed in order from

the first equation to the last, so if equation 4 asks for

equation 20 value, the equation 20 value will be the

value calculated in the previous run time cycle.

NO LIMIT

FALL 1 1 FALL (a);

This function is a falling edge trigger. When 'a'

transitions from true to false, this function's result is

true, otherwise it is false.

ICF 1 1 ICF (channel number);

This function's result will be true for one execution

cycle, if the value of the requested device input has had

at least one falling transition since the last execution

cycle. This is ideal for capturing events that occur faster

then the logic execution cycle.

NO LIMIT

ICR 1 1 ICR (channel number);

This function's result will be true for one execution

cycle, if the value of the requested device input has had

at least one rising transition since the last execution

cycle. This is ideal for capturing events that occur faster

then the logic execution cycle.

NO LIMIT

IN 1 1 IN (channel number);

This function's result will be the value of the requested

device input.

NO LIMIT

NOT 1 1 NOT (a);

This function's result will be the logical not of a.

NO LIMIT

OR 2 10 OR (a, b,...);

This function's result will be the logical or of a, b,...

NO LIMIT

OUT 1 1 OUT (channel number);

This function's result will be the value of the requested

device output.

NO LIMIT

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D-3

Rosemount 848L

PS 2 2 PS (channel number, divisor);

This function is a frequency prescaler. This function's

value will be true for 1 execution cycle each time the

requested device input has had 'divisor' pulses. This is

ideal for a scaling fast pulse inputs to a rate suitable for

the logic execution cycle.

RISE 1 1 RISE (a);

This function is a rising edge trigger. When 'a'

transitions from false to true, this function's result is

true, otherwise it is false.

RS 2 2 RS (set, reset);

This function is a reset dominant latch. When 'reset' is

true, this function will reset its' state to false regardless

of the value of 'set'. When 'reset' is false, the function's

state will have a false value until 'set' has had at least 1

true reading, after which the state will remain true. The

result of this function is the function's state.

SHL 3 4 SHL (a, clock, reset, bit);

This function is an 8 bit left shift register. When 'clock'

transitions from false to true, the value of 'a' is shifted

into the least significant bit of this function's register.

The remaining bits are shifted left by 1 bit position.

When 'reset' is true, all 8 bits in this function's register

will be cleared to zero. 'reset' is an optional parameter

and will always be considered false if it is not present.

The result of this function is the value of bit number 'bit'

in the register.

SHR 3 4 SHR (a, clock, reset, bit);

This function is an 8 bit right shift register. When 'clock'

transitions from false to true, the value of 'a' is shifted

into the most significant bit of this function's register.

The remaining bits are shifted right by 1 bit position.

When 'reset' is true, all 8 bits in this function's register

will be cleared to zero. 'reset' is an optional parameter

and will always be considered false if it is not present.

The result of this function is the value of bit number 'bit'

in the register.

SR 2 2 SR (set, reset);

This function is a set dominant latch. When 'set' is true,

this function will set its' state to true regardless of the

value of 'reset'. When 'reset' is false, the function's state

will have a false value until 'set' has had at least 1 true

reading, after which the state will remain true. When

reset is true, the function's state will be set to the value

of 'set'. The result of this function is the function's state.

TOF 2 2 TOF (a, time);

This function is an off delay. When 'a' is true, this

function will set its' output to true. When 'a' transitions to

false, the function's output will remain true for 'time' *

100 milliseconds before going false.

Table D-1. Supported Functions

Function Name

Required number

of parameters

Maximum number

of parameters Function Description

Maximum

Instances

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D-4

ERROR HANDLING The syntax of the entered equation is parsed when the target mode transitions

from OOS to AUTO. Each equation is checked in order, and when an error is

encountered in an equation, the parsing is suspended for the remaining

equations, and the target mode is set back to OOS. The equation where the

problem was encountered is indicated along with a message as shown in the

table below.

Bounds checking on the values of parameters used in the functions are

checked during run-time when ACTUAL MODE is AUTO. Errors of this type

will be indicated by a bad status in the equations computed value.

TON 2 2 TON (a, time);

This function is an on delay. When 'a' is false, this

function will set its' output to false. When 'a' transitions

to true, the function's output will remain false for 'time' *

100 milliseconds before going true.

TP 2 2 TP (a, time);

This function is a pulse timer. When 'a' transitions to

true, this function will set its' output to true for 'time' *

100 milliseconds, and then return false.

XOR 210 XOR(a, b,...);

This function is false if all parameters are in the same

state, either all true or all false. Otherwise the function

is true.

NO LIMIT

Table D-1. Supported Functions

Function Name

Required number

of parameters

Maximum number

of parameters Function Description

Maximum

Instances

Table D-2. Error Handling

Conditions Status response

No semi-colon appears in the equation. Missing semi-colon.

More left parenthesis than right parenthesis. Un-matched (.

More right parenthesis than left parenthesis. Un-matched ).

A comma placed without a preceding function parameter. Badly placed comma.

Open and Closed parenthesis without a parameter or

statement contained.

Empty ().

A semicolon is contained prior to finishing an expression. Badly placed semicolon.

A function call is missing one or more parameters. Too few parameters in function.

A bad character is present, or a parameter appears outside

of a function call.

Syntax error.

An unknown function is called out. Unknown function.

An opening parenthesis is located after the closing

parenthesis of a function call.

Badly placed (.

A function call contains too many parameters. Too many parameters in

function.

A decimal number was found where an integer was

expected.

Invalid number.

A function result was used as a function parameter where a

literal integer number was expected.

Invalid parameters in function.

A function has been used more than the maximum allowed

instances.

Insufficient resources.

All equations were parsed successfully. Equation completed.

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September 2004

D-5

Rosemount 848L

EXAMPLES Take value of input 1 and put it on output 3.... Set OUT3_EQ to:

IN(1);

For every transition (in both directions) on input 5, send a 200 msec pulse out

on output 2, but only if input 2 is low.... Set OUT2_EQ to:

AND(OR(TP(IN(5),2),TP(NOT(IN(5)),2)),NOT(IN(2)));

Turn on output 1 only after input 8 has gone high 10 times, start over counting

when input 6 is set high.... Set OUT1_EQ to:

CTU(IN(8),IN(6),10);

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September 2004

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D-6

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Appendix E Motor Control

Introduction to Motor Control . . . . . . . . . . . . . . . . . . . . . . page E-1

Variations on Motor Control . . . . . . . . . . . . . . . . . . . . . . . page E-2

Writing 848L Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . page E-4

INTRODUCTION TO

MOTOR CONTROL

Industrial motors require about a kilowatt per horsepower, usually delivered

as three phase AC at 440 volts or higher. This requires a special switch to turn

them on and off. The switch is called a contactor, in which a solenoid is

energized to pull a set of three power contacts to close the circuit to turn the

motor on. The contacts are large enough to carry the starting current without

welding. They are separated by insulation suitable for the supply voltage. The

solenoid is de-energized to turn the motor off. Springs quickly separate the

contacts to prevent arc damage, which can be severe at higher voltages. A

contactor for a 400 HP 2500 VAC motor may be housed in a steel box that is

two feet square and five feet high.

The three phase wires to the motor go through three overload heaters. There

are no contacts in this wiring, just heaters that mount on screw terminals. The

same contactor may be used for different motor sizes by changing the heater

overload rating. When an overload occurs, the heaters cause a contact to

open that is in series with the contactor’s solenoid, which removes power from

the motor. (This action is called a “trip” because it is mechanically like tripping

an alarm mechanism. Alarms are said to trip because the early electric bank

alarms used a trip wire to detect a robber.) The trip is supposed to happen

before the motor windings overheat and destroy their insulation. After things

have cooled off and someone has removed the cause of the overload, a reset

button must be pressed to close the heat triggered mechanical latch for the

overload contact. This allows power to flow in the solenoid circuit again.

The solenoid runs at a lower voltage than the motor, called the control

voltage. This voltage is taken from a transformer within the contactor

enclosure that is connected to two of the supply wires. The circuit breaker for

the contactor may be in another box somewhere. When the breaker is turned

off (or trips) the contactor enclosure is electrically dead, even for the control

voltage. The contactor’s solenoid may run at a higher voltage to get enough

power to move the contact assembly against its springs. A pilot relay is used

to switch that voltage within the enclosure. The control voltage seldom

exceeds 120 VAC or is less than 24 VAC. One side of the control voltage is

always grounded. Both the overload mechanism and the pilot relays are now

available in solid state form.

The enclosure containing the contactor, overload mechanism and control

power supply may be called a motor starter. The contactor’s solenoid or that

of the pilot relay carrying control voltage may be called a coil, as in relay coil.

A group of motor starters may be called a Motor Control Center (MCC).

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E-2

The contactor is never controlled with a toggle switch, because that would

leave one side of the solenoid electrically hot when the motor overload trips.

Standard procedure calls for start and stop push buttons in combination with

an auxiliary contact on the contactor. This contact closes when the solenoid is

energized and the motor contacts close. The auxiliary contact is rated for the

control voltage and current, and is far away from the high voltage motor

contacts. The stop button is normally closed and is in series with the control

power. The start button is normally open and is also in series with the control

power. The auxiliary contact is normally open and in parallel with the start

button. When the start button is pushed, the solenoid is powered and the

motor and auxiliary contacts eventually close. The start button can be

released and control power will continue to flow in the auxiliary contact. Two

things can stop the motor. Pressing the stop button removes power to the

solenoid, causing the auxiliary contact to eventually open along with the motor

power contacts. The stop button can then be released because there is no

complete circuit to the solenoid. The same thing happens if an overload trip

opens the circuit to the solenoid. When the overload is reset, no power will be

applied to the solenoid until the start button is pushed.

| ___ ___ Over |

| \_/STOP \_/START load |

| | | M | |

+--O|O-----+--O O--+------------( )---O|O--+ Contactor M

| | | |

| | M | |

| +--| |--+ |

VARIATIONS ON MOTOR

CONTROL

Interlock

There may be a process condition where it is not safe to run the motor. If this

condition can be detected and transformed into the change of state of a

contact, then the normally closed contact may be inserted in series with the

control voltage. If the interlocked condition occurs then the motor will not run

or start. An example is a low level condition in a tank feeding the suction of a

pump. The pump will be damaged if the suction goes dry, so a low level switch

is put in series with the control voltage for the pump’s motor starter.

Permissive

There may be a process condition that is required to be present when a motor

is started, but is not required once the motor is running. A contact that is

closed when the permissive condition is true is placed in series with the start

button. An example is auxiliary lubrication for a large motor that is required to

flood the bearing housings to prevent contact between the motor shaft and the

bearing material (not ball bearings). Once the motor is turning, lubrication is

maintained by shaft rotation and the auxiliary pump can be shut off.

Emergency Shutdown

A process may have an emergency shutdown requirement for all motors. This

requires a contact or logic input for all affected motor controls. For example,

there is an emergency stop button for a natural gas processing plant located

near the exit, so that the operator can hit it while running away.

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September 2004

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Rosemount 848L

Restart Delay

A motor may be used in a condition where starting is difficult, causing the

motor to heat rapidly until it gets running. That heat must be allowed to

dissipate before the motor is started again. A simple time delay prevents the

start button from working until a fixed delay time expires. Another example is

the time required for compressor head pressure to bleed off after the

compressor motor stops.

Maximum Restarts

Another way of handling difficult starts is to count the number of starts in a

given time and lock out the start button if the count is exceeded. Locking it out

means that the start button will not function until a latching relay has been

manually reset by an operator who has verified the safety of the situation.

Winding temperature

The above restart limiters may not be necessary if the winding temperature

can be measured and used as a permissive for starting. The winding

temperature sensor may be a ten ohm length of copper wire that is wound into

the motor along with the power windings.

Hand-Off-Auto

An operator may be required to perform some function near the motor, such

as clean a pump strainer or jog the motor to get its load into the right position.

The motor is normally controlled by the central system but must have a local

station to allow the local operator to control the motor. The local station has

buttons for Stop and Start, and a three position switch for Hand-Off-Auto

(HOA) selection. The control room has control when the switch is in the Auto

position. The motor will not run when the switch is in the Off position. The

Hand position allows the local start and stop buttons to control the motor. The

Off position is not as secure as the lockout procedure required when the

equipment or the operator would be damaged if the motor started. This

requires all concerned people to physically put a padlock on the Off position of

the main circuit breaker for the motor. The motor may be started after the last

person removes their lock.

Intermediate Stop

A reversible motor may be required to come to a complete stop before starting

to run in the other direction. This may be done with a timer or a motion sensor

on the motor (or driven load) shaft.

Redundant Motors

The process may require redundant motors for reliability. Usually this applies

to pumps, so that there is no mechanical connection between the two motors.

One pump may be shut off to replace seals (or the entire pump and motor)

while the redundant pump maintains flow in the line. There are three ways to

control redundant pumps:

Alternate Start

When the start button is pressed the pump that was not in use is started. Not

in use refers to now or since the last time start was pressed.

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E-4

Timed Switch

The pumps have a known life time within an acceptable risk, so one pump is

allowed to run until that time expires. The other pump automatically takes

over at that time.

Switch on Failure

If a process condition can be sensed that says the running pump failed, then

the other pump is started regardless of the starting protocol.

WRITING 848L

EQUATIONS

Basic Motor Control It is not easy to convert a functional diagram to an 848L equation because all

of the functions must be nested in the proper order. One way to begin the

process is to draw the functional diagram in ladder logic. The following is a

basic two button and auxiliary contact motor control that is drawn with channel

numbers.

| |

| 1 2 Out1 |

+--| |--+--||--+----------------------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--+ |

| |

Input 1 is from a normally closed stop button, which does not have to be

inverted in the equation. This is true for all stop buttons in the following

examples.

Input 2 is from the normally open start button and Input 3 is from the

contactor’s auxiliary contact.

The ladder coil shown is at Out1, which is the value of output equation 1.

Wires from output 1 will switch power from the control voltage to the

contactor’s solenoid or pilot relay.

Since the 848L uses RPN, begin from the lowest line in the ladder diagram

and work upwards.

The first expression is OR(IN(2),IN(3)) from “2 or 3” in the ladder diagram.

This is one term in an AND function, so build the function around it.

The top and final expression is AND(IN(1),OR(IN(2),IN(3))) from “1 and (2 or

3)” in the ladder diagram.

Enter the expression as the contents of parameter OUT1_EQ in the logic

transducer block. Do not forget to append the terminating semicolon.

Connect the buttons, auxiliary contact and contactor (a small relay will do) in

order to test the operation.

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Rosemount 848L

Interlock An interlock switch is easily added as follows, where input 4 is the normally

closed interlock:

| |

| 1 2 4 Out1 |

+--| |--+--||--+--|/|-----------------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--+ |

| |

• The first expression is still OR(IN(2),IN(3))

• The top and final expression is now AND(IN(1),OR(IN(2),IN(3)),IN(4));

Enter the expression and test as above.

Permissive A permissive switch may be added, with or without the interlock, as shown,

where 5 is the permissive:

| |

| 1 2 5 4 Out1 |

+--| |--+--||----||--+--|/|-----------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--------+ |

| |

• The first expression is now AND(IN(2),IN(5))

• The second expression is OR(AND(IN(2),IN(5)),IN(3))

• The final expression is AND(IN(1),OR(AND(IN(2),IN(5)),IN(3)),IN(4));

Emergency Shutdown In ladder logic, this would be shown as a switch for power to a section of the

ladder if there was more than one thing to be turned off. In the 848L, one

contact must be shown for each rung but only one input is required. The

shutdown contact is input 8 in the drawing below:

| |

| 1 2 5 4 8 Out1 |

+--| |--+--||----||--+--|/|----|/|----( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--------+ |

| |

• The first expression is still AND(IN(2),IN(5))

• The second expression is OR(AND(IN(2),IN(5)),IN(3))

• The final expression is

AND(IN(1),OR(AND(IN(2),IN(5)),IN(3)),IN(4),IN(8));

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September 2004

Rosemount 848L

E-6

Restart Delay An off delay timer is required as a permissive for starting the motor. When the

motor is started, the off delay contact opens the circuit for the start button and

keeps it open for a specified time. The motor will be cooled as it runs, so the

delay is only applied to the start. Motors that require this are usually large and

have long cooling times, like 30 to 100 minutes.

| |

| 3 T |

+--||---------------------------------( )--+ EQ1

| |

| 1 2 T Out1 |

+--| |--+--||----|/|--+---------------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||---------+ |

| |

Channels 1, 2, and 3 are the same as for basic motor control. T is the off

timer. Notice that this diagram depends on the order of execution of ladder

rungs. EQ1 is executed before OUT1_EQ. The value of EQ1 is initially false

because the motor is not running. The start button starts the motor. When the

confirm contact closes, EQ1 becomes true and breaks the start circuit, but the

confirm contact has closed and the motor stays running.

Each rung requires a separate equation in the 848L so that the execution

order can be preserved. Note that the output equations are always executed

last, so it is good practice to arrange the ladder diagram in execution order.

Rung T is equation 1. It generates a 60 minute pulse when the confirm

contact is true.

• The expression is TP(IN(3), 36000);

For rung Out1, the expression is basic motor control with input 2 in

series with T:

• The expression is AND(IN(1),OR(AND(IN(2),NOT(EQ(1)),IN(3)));

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September 2004

E-7

Rosemount 848L

Maximum Restarts A large motor is too expensive to replace if it burns up because the operator

wanted to give it another try, when in fact the pump was jammed. The life of

the contactor is also shortened when it has to interrupt locked rotor current. In

this case, it is normally possible for the motor to clear the jam on the second

or third try. A counter limits the number of starts to 3, for example, within a

preset time since the first attempt.

Notice that C1 in EQ1 and T2 in EQ2 are forward references that cannot have

a bad status. A Bad status at channel 2 (the start button) will propagate to all

of the equations and make the output Bad. A bad stop button or confirm

contact will only make the output Bad. The I/O transducer block parameter

OUT_1_CONFIG.FAIL_SAFE defaults to Fail False, which will stop the motor

on any bad input status, or it may be set to Fail Last Good, which will not allow

the stop button to turn it off. You probably don’t want to uses input devices

with status for this application.

| |

| 2 C1 T1 |

+--||------|/|------------------------( )--+ EQ1

| |

| T1 +-----+ C |

+--||--------------------|Count|------( )--+ EQ2

| T2 | | |

+--||--------------------|Reset| |

| +-----+ |

| |

| C T2 |

+--||---------------------------------( )--+ EQ3

| |

| 1 T1 Out1 |

+--| |--+--||--+----------------------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--+ |

| |

Rung T1 is equation 1. The pulse time must be set to the allowable on time for

the locked rotor condition to prevent tripping the overloads, in this case 2.5

seconds.

• The expression is TP(AND(IN(2),NOT(EQ(2))), 25);

Rung C is equation 2, which counts the attempts to start, and holds at the

count until the 30 minute timer expires.

• The expression is CTU(RISE(EQ(1)),EQ(5), 3);

Rung T2 is equation 3, the 30 minute timer:

• The expression is TON(EQ(2),18000);

Rung Out1 is output equation 1:

• The expression is AND(IN(1),OR(EQ(1),IN(3)));

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September 2004

Rosemount 848L

E-8

Winding Temperature The multi-rung delay mechanism above may be replaced if the motor has a

winding temperature sensor and a convertor that opens a contact when the

motor is too hot and closes when it is sufficiently cool. The following drawing

applies such a contact (as input 4) to the Restart Delay diagram, which

reduces it to a permissive circuit.

| |

| 1 2 4 Out1 |

+--| |--+--||----||--+----------------( )--+ OUT1_EQ

| | | |

| | 3 | |

| +--||--------+ |

| |

The equations for a permissive circuit have already been described.

• The expression is AND(IN(1),OR(AND(IN(2),IN(4)),IN(3));

NOTE

This is not an interlock for high winding temperature. That is taken care of by

the overloads. The purpose of this circuit is to prevent starting if the motor is

too hot, such that the heat generated by starting would exceed the

temperature rating of the motor. When the motor starts, the temperature will

rise and open the safe temperature contact. This will happen after the

auxiliary contact has closed, so the motor will continue to run. As it runs, it is

cooled by an internal fan and eventually the safe temperature contact closes.

An interlock could be added, but the temperature would have to be set much

higher than the safe restart temperature.

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September 2004

E-9

Rosemount 848L

Hand-Off-Auto The HOA switch has one contact that is closed in the Hand position (input 1)

and one contact that is closed in the Auto position (input 2). Both contacts are

open in the Off position. The local hand controls are Stop (input 3) and Start

(input 4). These require the auxiliary contact on the starter (input 5). Auto

control is done in some DCS function blocks that generate a Run signal which

is linked over an H1 fieldbus to a DO block in the 848L. This is the equivalent

of a toggle switch, so the 848L logic breaks it up into start and stop signals. A

pulse timer is required to extend the rise of the DCS Run signal until the

confirm contact can pull in. An operator will hold the start button in until

something happens. The DCS logic needs to know when the HOA switch is in

the Auto position and also the state of the auxiliary contact, so DI blocks are

configured for them. The ladder diagram looks like this:

| |

| DO1 5 T |

+--|^|-----|/|------------------------( )--+ EQ1

| |

| 1 3 4 Out1 |

+--||-----| |--+--||--+------+--------( )--+ OUT1_EQ

| | | | |

| | 5 | | |

| +--||--+ | |

| | |

| 2 DO1 T | |

+--||------||--+--||--+------+ |

| | | |

| | 5 | |

| +--||--+ |

| |

First, instantiate two DI blocks and a DO block. Set the DO channel to 9. Set

the Auto DI channel to 2 and the Contactor DI channel to 5. Use appropriate

configuration for the other data in the blocks, such as Tag.

Rung T is equation 1. This is necessary because the Out1 equation has 70

characters, not because it is needed in two or more equations.

• The expression is TP(AND(RISE(DO(1)), NOT(IN(5))),30);

Rung Out1 is output equation 1. The first expression and the second are basic

motor control expressions with an additional selector contact.

• The expression is

OR(AND(IN(1),IN(3),OR(IN(4),IN(5))),AND(IN(2),DO(1),

OR(EQ(4),IN(5))));

To test this, use the usual buttons and relay along with a selector switch and

manual operation of the DO block.

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September 2004

Rosemount 848L

E-10

Intermediate Stop A reversible motor requires two contactors. One of them swaps two of the

motor wires so that it will run in the opposite direction. The contactors must

never be closed at the same time, because that would place a short circuit

across one of the three phases. Furthermore, motors with lots of attached or

internal inertia can be damaged if the shaft does not come to rest before

starting up in the other direction. Sometimes a brake is used to reduce the

stopping time. The Forward/Reverse selector switch has one contact that is

closed in the Forward position (input 1) and one contact that is closed in the

Reverse position (input 2). The center of the three position selector is Off. The

push button controls are Stop (input 3) and Start (input 4). These require the

auxiliary contact on each starter (input 5 and 6). A 30 second off delay timer is

used. The following ladder diagram shows one way of doing this:

| |

| 5 T |

+--||--+------------------------------( )--+ EQ1

| | |

| 6 | |

+--||--+ |

| |

| 1 3 4 T Out2 Out1 |

+--||-----| |--+--||---|/|--+--|/|----( )--+ OUT1_EQ

| | | |

| | 5 | |

| +--||--------+ |

| |

| 2 3 4 T Out1 Out2 |

+--||-----| |--+--||---|/|--+--|/|----( )--+ OUT2_EQ

| | | |

| | 6 | |

| +--||--------+ |

| |

Rung T is equation 1. It is necessary because it is needed in two equations

and because the equations would be 80 characters long without the

semicolon.

• The expression is TOF(OR(IN(5),IN(6)),300);

Rung Out1 is output equation 1. This is basic motor control with additional

contacts.

• The expression is

AND(IN(1),IN(3),OR(AND(IN(4),NOT(EQ(1)),IN(5)),NOT(OUT(2));

Rung Out2 is output equation 2. This is also basic motor control with

additional contacts.

• The expression is

AND(IN(2),IN(3),OR(AND(IN(4),NOT(EQ(1)),IN(6)),NOT(OUT(1));

If a brake was required, it could be controlled by output equation 3:

• The expression is AND(EQ(1), NOT(IN(5)),NOT(IN(6)));

This simulation requires two relays in addition to the switches.

Reference Manual

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September 2004

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Rosemount 848L

Redundant Motors -

Alternate Start

Two motors drive two pumps in a redundant configuration. The control valve

that follows the pumps will just waste the energy of the second pump, possibly

damaging the valve, if both pumps on at the same time. There are times when

neither pump is required. When a pump is required, the pump that was not in

use last time should be started to equalize the wear on the pumps. The push

button controls are Stop (input 1) and Start (input 2). An auxiliary contact is

required from each starter (inputs 3 and 4).

| |

| 3 4 2 P |

+--|/|----|/|-----|^|-----------------( )--+ EQ1

| |

| P L +-----+ L |

+--||-----|/|------------|Set |------( )--+ EQ2

| P L | | |

+--||-----| |------------|Reset| |

| +-----+ |

| |

| 1 2 L Out2 Out1 |

+---------| |--+--||--+--|/|---|/|----( )--+ OUT1_EQ

| | 3 | |

| +--||--+ |

| |

| 1 2 L Out1 Out2 |

+---------| |--+--||--+--| |---|/|----( )--+ OUT2_EQ

| | 4 | |

| +--||--+ |

| |

Rung P is equation 1. It generates the pulse that will toggle the latch. The

pulse comes from the RISE function.

• The expression is AND(NOT(IN(3)),NOT(IN(4)),RISE(IN(2)));

Rung L is equation 2. It latches on when L was false and unlatches when L

was true.

• The expression is RS(AND(EQ(1),NOT(EQ(2)),AND(EQ(1),EQ(2)));

Rung Out1 is output equation 1. This is basic motor control with additional

contacts.

• The expression is

AND(IN(1),OR(IN(2),IN(3)),NOT(EQ(2)),NOT(OUT(2)));

Rung Out2 is output equation 2. This is also basic motor control with

additional contacts.

• The expression is AND(IN(1),OR(IN(2),IN(4)),EQ(2),NOT(OUT(1)));

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September 2004

Rosemount 848L

E-12

Redundant Motors -

Timed Switch

Again, redundant pumps are used but only one pump runs at a time. The

process runs for years without being shut down. The switch between pumps

occurs at a time near the end of the useful life of the pump, usually several

thousand hours. Stopping the old pump is delayed by a TOF while the other

pump comes up to speed, which the control valve can handle. The push

button controls are Stop (input 1) and Start (input 2). An auxiliary contact is

required from each starter (inputs 3 and 4). The life time is measured in

thousands of hours, so an external retentive timer with a display is used.

Timing power comes from Out2, reset power from Out1 and the timed out

contact comes in at channel 5.

Actually, this scheme is not practical unless the latches are non-volatile.

| |

| 2 +-----+ L1 |

+--| |-------------------|Set |------( )--+ EQ1

| 1 | | |

+--|/|-------------------|Reset| |

| +-----+ |

| 5 P1 |

+--|^|--------------------------------( )--+ EQ2

| |

| P1 L2 +-----+ L2 |

+--| |----|/|------------|Set |------( )--+ EQ3

| P1 L2 | | |

+--| |----| |------------|Reset| |

| +-----+ |

| L1 Out1 |

+--|^|--+-----------------------------( )--+ OUT1_EQ

| | |

| P1 | |

+--| |--+ |

| |

| 3 Out1 Out2 |

+--| |--+--|/|------------------------( )--+ OUT2_EQ

| | |

| 4 | |

+--| |--+ |

| |

| L1 L2 Out1 Out3 |

+--| |----|/|--+--| |--+--------------( )--+ OUT3_EQ

| | | |

| | 3 | |

| +--| |--+ |

| |

| L1 L2 Out1 Out4 |

+--| |----| |--+--| |--+--------------( )--+ OUT4_EQ

| | | |

| | 4 | |

| +--| |--+ |

| |

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Rosemount 848L

Rung L1 is equation 1. It latches on when the start button is true and

unlatches when the NC stop button is pushed. The latch remembers start and

stop commands to simplify the logic.

• The expression is RS(IN(2),NOT(IN(1)));

Rung P1 is equation 2, which generates a pulse from one read of channel 5:

• The expression is TON(AND(OR(IN(3),IN(4)),NOT(EQ(2))),30000);

Rung L2 is equation 3. The latch determines which motor to start and run. It

toggles when the life time is reached. That stops the running motor (after its

off delay) and enables the other motor to be started.

• The expression is RS(AND(EQ(2),NOT(EQ(3)),AND(EQ(2),EQ(3)));

Rung Out1 is output equation 1. A timed start pulse is delivered to both motor

circuits when either the start button is pressed to set the Run latch or the end

of the hour count toggles the selector latch. Only the enabled circuit will start.

The output resets the external timer.

• The expression is TP(OR(RISE(EQ(1)),EQ(2)),20);

Rung Out2 is output equation 2. Power goes to the external timer while either

confirm is true, but not during reset.

• The expression is AND(OR(IN(3),IN(4)),NOT(OUT(1)));

Rung Out3 is output equation 3. This is basic motor control with an off delay of

5 seconds to maintain flow.

• The expression is

TOF(AND(EQ(1),NOT(EQ(3)),OR(OUT(1),IN(3)),50);

Rung Out4 is output equation 4. This is also basic motor control with an off

delay.

• The expression is TOF(AND(EQ(1),EQ(3),OR(OUT(1),IN(4)),50);

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September 2004

Rosemount 848L

E-14

Redundant Motors -

Switch on Failure

Again, there are redundant pumps. There is a pressure switch in the common

discharge line. If the pressure falls then the other pump is started. If the

pressure does not recover, possibly because a flammable liquid is pouring on

the ground from a broken pump housing, then the alternate pump is stopped.

The push button controls are Stop (input 1) and Start (input 2). An auxiliary

contact is required from each starter (inputs 3 and 4). The pressure switch is

linked into a DO that is true when the pressure is low.

| |

| 3 4 2 +-----+ L1 |

+--|/|-----|/|-----| |---|Set |------( )--+ EQ1

| 1 | | |

+--|/|--+----------------|Reset| |

| T | +-----+ |

+--| |--+ |

| |

| DO P |

+--|^|--+-----------------------------( )--+ EQ2

| L1 | |

+--|^|--+ |

| |

| DO L1 T |

+--| |-----| |------------------------( )--+ EQ4

| |

| P L2 +-----+ L2 |

+--|^|----|/|------------|Set |------( )--+ EQ4

| P L2 | | |

+--|^|----| |------------|Reset| |

| +-----+ |

| |

| L1 P L2 Out2 Out1 |

+---------| |--+--||--+--|/|---|/|----( )--+ OUT1_EQ

| | 3 | |

| +--||--+ |

| |

| L1 P L2 Out1 Out2 |

+---------| |--+--||--+--| |---|/|----( )--+ OUT2_EQ

| | 4 | |

| +--||--+ |

| |

Instantiate a DO block and set the channel number to 9.

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September 2004

E-15

Rosemount 848L

Rung L1 is equation 1. It latches on when the start button is true and neither

motor is running. It unlatches when the NC stop button is pushed or the

pressure stays low for too long.

• The expression is RS(AND(NOT(IN(3)),

NOT(IN(4)),IN(2)),OR(NOT(IN(1)),EQ(3));

Rung P is equation 2, which generates a 2 second start pulse from the rise of

the run latch or the rise of the low pressure condition. This pulse toggles the

latch and starts the selected motor.

• The expression is TP(OR(RISE(DO(1)),RISE(EQ(1))),20);

Rung T is equation 3, which is a TON that is run by the on state of the low

pressure and the run latch.

• The expression is TON(AND(DO(1),EQ(1)),100);

Rung L2 is equation 4. The latch determines which motor to start and run. It

toggles when equation 2 generates a pulse. The pulse duration is more than

one evaluation cycle, so rise functions are required.

• The expression is

RS(AND(RISE(EQ(2)),NOT(EQ(4))),AND(RISE(EQ(2)),EQ(4)));

Rung Out1 is output equation 1. This is basic alternate motor control.

• The expression is

AND(EQ(1),OR(EQ(2),IN(3)),NOT(EQ(4)),NOT(OUT(2)));

Rung Out2 is output equation 2. This is also basic alternate motor control.

• The expression is AND(EQ(1),OR(EQ(2),IN(4)),EQ(4),NOT(OUT(1)));

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September 2004

Rosemount 848L

E-16

Reference Manual

00809-0100-4696, Rev AA

September 2004 Rosemount 848L

www.rosemount.com

Appendix F Valve Control

Introduction to Valve Control . . . . . . . . . . . . . . . . . . . . . . page F-1

INTRODUCTION TO

VALVE CONTROL

Industrial valves have two general classifications, regulating and block. A

regulating valve is designed to be stable at any one of a nearly infinite set of

positions between open and closed. They are mostly used in control loops so

that nonlinearity and friction are corrected by feedback control. A block valve

is designed to be either tight shut or wide open. They are mostly used to

change the configuration of process equipment, such as a heat exchanger

that can be used to heat or cool, but not both at the same time. Block valves

configure steam in and condensate out for heating or chilled brine in and

return for cooling. Regulating valves are being used as block valves when the

actual position of the valve must be known, but analog outputs are used.

Block valves generally have some kind of switch that is closed in the open

position and another switch for the closed position. These are called confirm

contacts even if they are proximity switches. The valve position is unknown

when neither switch is closed. If the valve actuator has adequate power then it

is rare to find both switches open, except for a period of time known as the

travel time when the valve is moving from one position to the other. Actuators

can be hydraulic pistons, pneumatic pistons or diaphragms, or motor driven

screws, in order of increasing travel time. More than 80% of the actuators use

compressed, oil and water free air for power. Valves are referred to as air to

open or air to close.

A block valve may be controlled by push buttons or by a toggle switch. There

is no contactor as there is for a motor. Permissive and interlock circuits may

be applied. The actuator may require power to be applied to open it, with a

spring to return it to the closed position, or vice-versa. A block valve may be

required to stay in its last position on air or power failure, so there is one pilot

actuator to open it and another pilot actuator to close it. The pilot actuator is

not usually designed for continuous power, so a few second pulse may be all

that is required. The actuator is called a pilot because it just directs the flow of

fluid power, as by pushing a spool valve from one side to the other. The spool

valve directs the main flow to one side of the main actuator or the other, like

the pilot valve in a power steering system. Two pilot solenoid valves are

required if the spool latches in position, or one if the spool has a spring return.

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September 2004

Rosemount 848L

F-2

There are at least three permutations of any valve circuit:

1. Steady or pulse output to the pilot solenoid (or whatever, piezoelectric

bars are in use). Steady requires one output, pulse requires two.

2. Confirmed position switches for open, closed or both, using one or

two inputs.

3. Automatic control or a local selector for Open-Auto-Close using no or

two inputs (these are not common).

Interlock and permissive may be additional permutations.

Alarms If a valve has one or both position switches then it is possible to alert the

operator to the fact that the valve is not where it should be. This is not a

permuted choice because the main reason for having position switches is to

alarm this condition. It is not a simple alarm because time must be allowed for

the valve to complete its stroke after it receives a command. An On Delay

timer set for the travel time is required.

All numbers in 848L equations are examples. The user will want to change

them.

Variations on Valve

Control

Interlock

There may be a process condition where it is not safe to open the valve. If this

condition can be detected and transformed into the change of state of a

contact, then the normally closed contact may be inserted in series with the

control output. If the interlocked condition occurs then the valve will close if

open or stay closed. An example is the drain valve of a batch reactor, which

may have two interlocks. One prevents opening the drain if any feed valve is

open. The other will not let material in the reactor drain into a tank that isn’t

ready for it.

Permissive

There may be a process condition that is required to be present when a valve

is opened, but is not required once it has been opened. A contact that is

closed when the permissive condition is true is placed in series with the open

command. A latch is required because the permissive may go false after the

valve is opened. One application for a permissive involves a gas storage tank.

The pressure must be above a certain amount to allow the valve to be

opened, but once opened, the pressure will fall below the permissive level.

Open-Auto-Close

An operator may be required to perform some function near the valve, such

as unplugging a pipe or locally directing material flow. The valve is normally

controlled by the central system but must have a local station to allow the

local operator to control it. The local station has a three position switch for

Open-Auto-Close selection. The control room has control when the switch is

in the Auto position. If the switch is turned to Open then the valve will open,

possibly bypassing interlocks, and the same for Close. There is no bump

going through Auto because the command is either Open or Close.

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September 2004

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Rosemount 848L

Double Block and Bleed

If the valve absolutely must not leak into the process, then two valves are put

in series and the short pipe between them is vented (bled) to an appropriate

place. The bleed valve must be shut before the main valves can be opened,

and the main valves must both be closed before the bleed valve can be

opened.

Motorized Valve

The actuator is a reversible motor that turns a lead screw that moves the

valve stem. Two confirms are required because the motor is only free to turn

while the valve stem is travelling. Outputs are required for the Forward and

Reverse motor directions. If a big motor-driven valve takes a minute to

change position, that’s a long time to find out that it didn’t move. The crack

time is a period of time in which the previously closed contact must open, to

confirm that the actuator is moving and the valve is not stuck or powerless.

Heat Exchange Medium Selection

Batch heat exchangers have to use different media to heat and cool. If the

media are compatible, like steam and chilled water, then a simple four valve

manifold can handle the selection. The four valves are independent because

it is necessary to drain one medium from the exchanger before using the

other. There are many variations on this theme, for incompatible media or

more than two choices.

Boolean Expressions The motor control descriptions used ladder logic. Another method that takes

less room on the back of an envelope is the Boolean expression. The

following is a comparison of Boolean and ladder operators (math operators

are +,-,*,/). Only three operators are used in the examples:

Functions are the same as 848L functions. The examples use TON, TOF and

TP.

Basic Valve Control Since very few applications exist for local valve control that are more than a

simple toggle switch (electric or pneumatic), all examples use a DO block to

take a command from Fieldbus. The DO point is on for open and off for close

in all cases.

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September 2004

Rosemount 848L

F-4

Open-Auto-Close Those applications that use a local switch with automatic control have a three

position switch arranged as Open-Auto-Close. Inputs 1 and 2 are used for

confirms, so input 3 is used for Open and input 4 for Closed. No input is

required for Auto.

• The Boolean expression is:

• The 848L expression is:

• EQ1 contains OR(AND(NOT(IN(4)),DO(1)),IN(3));

Alarm Variations If there is just one close confirm on input 2, then the Boolean expression is:

ALARM = TON ( ( !DO1 & !IN2 ) | ( DO1 & IN2 ), TravelTime)

If there is just one open confirm on input 1, then the Boolean expression is:

ALARM = TON ( ( DO1 & !IN1 ) | ( !DO1 & IN1 ), TravelTime)

It both confirms are used, then the Boolean expression is:

ALARM = TON ( ( !DO1 & !IN2 ) | ( DO1 & !IN1 ) | ( IN1 & IN2 ),

TravelTime)

The equivalent 848L expressions are:

TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),IN(2))),100);

TON(OR(AND(DO(1),NOT(IN(1)),AND(NOT(DO(1)),IN(1))),110);

TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),NOT(IN(1)),AND(IN(

1),IN(2))),120);

The chosen expression goes in the last expression used, which must be

linked to a DI to generate an alarm.

Output Variations A valve actuator may be spring return, requiring one output, or bistable,

requiring two outputs. Output 1 is used for Open and output 2 for Close.

Bistable valves often require a short pulse instead of maintained power. The

848L expressions for spring return are:

OUT1 contains DO(1);

or bistable has:

OUT1 contains TP(DO(1),30);

OUT2 contains TP(NOT(DO(1)),30);

Output with Interlock The interlock may be wired, or internal, or from the bus.

The example uses a DO from the bus:

OUT1 contains TP(AND(DO(1),DO(3)),30); spring return is

AND(DO(1),DO(3));

OUT2 contains TP(OR(NOT(DO(1)),NOT(DO(3))),30);

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September 2004

F-5

Rosemount 848L

Simple Valve Variations A spring return valve with one close confirm:

EQ1 contains

TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),IN(2))),100);

OUT1 contains DO(1);

The fourth similar spring return valve in the same 848L:

EQ4 contains

TON(OR(AND(NOT(DO(4),NOT(IN(8))),AND(DO(4),IN(8))),100);

OUT4 contains DO(4);

A bistable valve with both confirms and a local station:

EQ1 contains OR(AND(NOT(IN(4)),DO(1)),IN(3));

EQ2 contains

TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),NOT(IN(1)),AND(IN(

1),IN(2))),120);

OUT1 contains TP(DO(1),30);

OUT2 contains TP(NOT(DO(1)),30);

The second similar bistable valve in the same 848L:

EQ3 contains OR(AND(NOT(IN(8)),DO(2)),IN(7));

EQ4 contains

TON(OR(AND(NOT(DO(2)),NOT(IN(6))),AND(DO(2),NOT(IN(5)),AND(IN(

5),IN(6))),120);

OUT3 contains TP(DO(2),30);

OUT4 contains TP(NOT(DO(2)),30);

Permissive The permissive may be wired, or internal, or from the bus. The example uses

DO3 from the bus. The confirmed open switch is used to hold the valve open

if the permissive goes away. If the valve is spring return:

OUT1 contains AND(DO(1),OR(DO(3),IN(1)));

A bistable valve does not need a latch:

OUT1 contains TP(AND(DO(1),DO(3)),30);

OUT2 contains TP(NOT(DO(1)),30);

Either way, the alarm equation for just the open confirm is:

TON(OR(AND(DO(1),NOT(IN(1)),AND(NOT(DO(1)),IN(1))),110);

The alarm equation for both confirms is:

TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),NOT(IN(1)),AND(IN(

1),IN(2))),120);

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September 2004

Rosemount 848L

F-6

Double Block and Bleed Certain materials must not leak through a valve that is supposed to be shut.

Three valves are arranged in a leak-proof configuration as shown:

All three valves are spring return. V1 and V2 return to closed, V3 returns to

open. All 3 valves must have closed confirm switches, which allows two

instances per 848L. If open confirms are also used, the alarm logic is different

and only one instance per 848L is possible. V1 and V2 must both confirm

closed in order to open the bleed valve by removing power to it. V3 must be

closed (powered) to allow V1 and V2 to open. Since V1 and V2 operate

together, they are both powered by the same output. The second output

operates V3. The close confirms take inputs of the same number as the valve.

A second instance takes inputs of the same number as the valve plus four.

Open confirms take inputs of the same number as the valve plus three. DO1

is still the open/close command.

The outputs are the same whether or not there are open confirms.

OUT1 contains AND(DO(1),IN(3));

OUT2 contains NOT(AND(NOT(DO(1)),IN(1),IN(2)));

For single closed confirms, the valve assembly is confirmed open if V1 and V2

do not confirm closed and V3 confirms closed. The assembly is confirmed

closed if V1 and V2 confirm closed and V3 does not confirm closed. The

alarm is true if any of these conditions is false after the travel time has

expired. The equation will not fit on one line, so two must be used:

EQ1 contains AND(NOT(DO(1)),OR(NOT(IN(1)),NOT(IN(2)),IN(3)));

EQ2 contains

TON(OR(AND(DO(1),OR(IN(1),IN(2),NOT(IN(3))),EQ(1)),110);

For both confirms, the valve assembly is confirmed closed if V1 and V2

confirm closed and V3 confirms open. The assembly is confirmed open if V1

and V2 confirm open and V3 confirms closed.

EQ1 contains AND(NOT(DO(1)),NOT(AND(IN(1),IN(2),IN(6))));

EQ2 contains

TON(OR(AND(DO(1),NOT(AND(IN(4),IN(5),IN(3)))),EQ(1)),140);

848L/DOUBLEBLOCK.TIF

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September 2004

F-7

Rosemount 848L

Motorized Valve The motor runs forward to open the valve and reverse to close it. When the

motor is off, the valve cannot move. Both confirms are required. Output 1

causes the motor to run forward, Output 2 is reverse. Only one output must be

active at a time. Input 1 confirms that the valve is open and input 2 confirms

closed.

OUT1 contains AND(DO(1),NOT(IN(1)),NOT(EQ(2)));

OUT2 contains AND(NOT(DO(1)),NOT(IN(2)),NOT(EQ(2)));

The alarm interacts with the motor drive so that power is not applied after the

travel time expires. This prevents burnout of small motors that do not have a

motor starter. A crack time alarm is also used in case the valve is stuck. Since

this works even for small motors, there is no point to making it optional. The

crack time is 5 seconds in this example and the travel time is 30 seconds.

EQ1 contains

TON(OR(AND(IN(1),IN(2)),AND(DO(1),IN(2)),AND(NOT(DO(1)),IN(2))),5

0);

EQ2 contains

OR(TON(OR(AND(NOT(DO(1)),NOT(IN(2))),AND(DO(1),NOT(IN(1))),300

),EQ(1));

Heat Exchange Medium

Selection

The media are steam and chilled water. DO1 is on to select heating with

steam and off to select cooling with water. All four valves have both confirms,

as follows:

Steam condensate must drain and both steam valves be closed before the

water valves are opened. The water must drain and both water valves be

closed before the steam valves are opened. There is a steam trap after the

steam outlet valve to prevent steam from blowing through the heat exchanger.

The opening of the steam outlet valve is delayed to allow some condensate to

form in the exchanger for proper operation of the trap.

OUT1 contains AND(DO(1),IN(7),IN(8));

OUT2 contains TOF(TON(OUT(1), 1200),1800);

OUT3 contains AND(NOT(DO(1)),IN(5),IN(6));

OUT4 contains TOF(OUT(3),1600);

Heating is confirmed if In1 and In2 and In7 and In8 are on. Travel time must

include the water drain delay time and the steam outlet opening delay.

Cooling is confirmed if In3 and In4 and In5 and In6 are on. Travel time must

include the steam drain delay time.

EQ1 contains

TON(AND(NOT(DO(1)),NOT(AND(IN(3),IN(4),IN(5),IN(6)))),1900);

EQ2 contains

OR(TON(AND(DO(1),NOT(AND(IN(1),IN(2),IN(7),IN(8))),2900),EQ(1));

Valve Output Opened Closed

Steam In Out1 In1 In5

Steam Out Out2 In2 In6

Water In Out3 In3 In7

Water Out Out4 In4 In8

Reference Manual

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September 2004

Rosemount 848L

F-8

Reference Manual

00809-0100-4696, Rev AA

9/17/04 Rosemount 848L

www.rosemount.com

Index

Numerics

2-Inch Pipe Stand

Mounting . . . . . . . . . . . . . . . . . . 2-3

ADVISE_ACTIVE . . . . . . . . . . . . . 3-8

ADVISE_ALM . . . . . . . . . . . . . . . . 3-8

ADVISE_ENABLED . . . . . . . . . . . 3-7

ADVISE_MASK . . . . . . . . . . . . . . 3-7

ADVISE_PRI . . . . . . . . . . . . . . . . 3-7

Advisory Alarms . . . . . . . . . . . . . . 3-7

ADVISE_ACTIVE . . . . . . . . . . . 3-8

ADVISE_ALM . . . . . . . . . . . . . . 3-8

ADVISE_MASK . . . . . . . . . . . . 3-7

ADVISE_PRI . . . . . . . . . . . . . . 3-7

Alarms

ADVISE_ACTIVE . . . . . . . . . . . 3-8

ADVISE_ALM . . . . . . . . . . . . . . 3-8

ADVISE_MASKParameter

ADVISE_MASK . . . . . . . . . 3-7

ADVISE_PRI . . . . . . . . . . . . . . 3-7

Advisory . . . . . . . . . . . . . . . . . . 3-7

Configuration . . . . . . . . . . . . . . 3-9

FAILED_ACTIVE . . . . . . . . . . . 3-6

FAILED_ALARMS . . . . . . . . . . 3-6

FAILED_ALM . . . . . . . . . . . . . . 3-6

FAILED_ENABLED . . . . . . . . . 3-6

FAILED_MASK . . . . . . . . . . . . . 3-6

FAILED_PRI . . . . . . . . . . . . . . . 3-6

MAINT_ACTIVE . . . . . . . . . . . . 3-7

MAINT_ALARMS . . . . . . . . . . . 3-7

MAINT_ALM . . . . . . . . . . . . . . . 3-7

MAINT_ENABLED . . . . . . . . . . 3-7

MAINT_MASK . . . . . . . . . . . . . 3-7

MAINT_PRI . . . . . . . . . . . . . . . 3-7

PlantWeb . . . . . . . . . . . . . 3-6, 3-8

Valve Control . . . . . . . . . . . . . . F-2

Analog Input

Ground . . . . . . . . . . . . . . . . . . . 2-5

Analog Input Function Block

Parameters . . . . . . . .C-1, C-5, C-8

Approvals

European . . . . . . . . . . . . . . . . . B-2

North American . . . . . . . . . . . . B-1

Approved Manufacturing Locations B-1

Boolean Expressions

Valve Control . . . . . . . . . . . . . . F-3

Cable Glands

Installation . . . . . . . . . . . . . . . . . 2-9

Capabilities . . . . . . . . . . . . . . . . . . 3-4

Block Execution Times . . . . . . . 3-4

Host Timer . . . . . . . . . . . . . . . . 3-4

VCRs . . . . . . . . . . . . . . . . . . . . 3-4

Changing Modes . . . . . . . . . . . . . . 3-2

Commissioning . . . . . . . . . . . . . . . 4-2

Tag . . . . . . . . . . . . . . . . . . . . . . 2-8

Conduit Entries . . . . . . . . . . . . . . 2-10

Configuration

Alarms . . . . . . . . . . . . . . . . . . . . 3-9

Reset . . . . . . . . . . . . . . . . . . . . 4-2

Restart Processor . . . . . . . . 4-2

Restart with Defaults . . . . . . 4-2

Resource Block . . . . . . . . . . . . . 3-4

DIN Rail

Mounting . . . . . . . . . . . . . . . . . . 2-2

Discrete Input Block . . . . . . . . . . .C-9

Parameters . . . . . . . . . . . . . . .C-10

Discrete Input Blocks

Multipule . . . . . . . . . . . . . . . . .C-12

Discrete Output Block . . . . . . . . . C-11

Parameters . . . . . . . . . . . . . . .C-12

Discrete Output Blocks

Multipule . . . . . . . . . . . . . . . . .C-13

Drawing

Switch Location . . . . . . . . . . . . . 2-5

Drawings

Block Diagram . . . . . . . . . . . . . 4-1

Cable Gland Installation . . . . . . 2-9

Commissioning Tag . . . . . . . . . 2-8

Conduit Entries Installation . . . 2-10

Dimensional . . . . . . . . . . . . . . . A-5

Error Handling

Logic Equation Syntax . . . . . . .D-4

European Directive . . . . . . . . . . . .B-1

Execution Times . . . . . . . . . . . . . . 3-4

FAILED_ACTIVE alarms . . . . . . . . 3-6

FAILED_ALARMS . . . . . . . . . . . . . 3-6

FAILED_ACTIVE . . . . . . . . . . . . 3-6

FAILED_ALM . . . . . . . . . . . . . . 3-6

FAILED_ENABLED . . . . . . . . . . 3-6

FAILED_MASK . . . . . . . . . . . . . 3-6

FAILED_PRI . . . . . . . . . . . . . . . 3-6

FAILED_ALM . . . . . . . . . . . . . . . . . 3-6

FAILED_ENABLED alarms . . . . . . 3-6

FAILED_MASK alarms . . . . . . . . . 3-6

FAILED_PRI alarms . . . . . . . . . . . 3-6

FEATURES

FEATURES_SEL . . . . . . . . . . . 3-5

Features . . . . . . . . . . . . . . . . . . . . 3-4

FEATURES, FEATURES_SEL . . . 3-4

Features . . . . . . . . . . . . . . . . . . 3-4

Reports . . . . . . . . . . . . . . . . . . . 3-4

Soft W Lock, Hard W Lock . . . . 3-5

Unicode . . . . . . . . . . . . . . . . . . . 3-4

Foundation Fieldbus . . . . . . . . . . . 4-1

Check . . . . . . . . . . . . . . . . . . . . 4-2

Troubleshooting . . . . . . . . . . . . 4-3

Function Block

Specifications . . . . . . . . . . . . . .A-4

Functional

Specifications . . . . . . . . . . . . . .A-1

General Block Information

Block Instantiation . . . . . . . . . . . 3-2

Capabilities . . . . . . . . . . . . . . . . 3-2

Link Active Scheduler . . . . . . . . 3-2

Modes . . . . . . . . . . . . . . . . . . . . 3-2

Grounding . . . . . . . . . . . . . . . . . . . 2-5

Analog Device . . . . . . . . . . . . . . 2-5

Grounded Thermocouple . . . . . 2-5

Transmitter Enclosure . . . . . . . . 2-5

Reference Manual

00809-0100-4696, Rev AA

9/17/04

Rosemount 848L

Index-2

Hardware

Maintenance . . . . . . . . . . . . . . . 4-2

Communication Check . . . . 4-2

Power Check . . . . . . . . . . . 4-2

Reset Configuration . . . . . . 4-2

Sensor Check . . . . . . . . . . . 4-2

I/O Transducer

Parameters . . . . . . . . . . . . . . . . C-5

Installation . . . . . . . . . . . . . . . . . . . 2-9

Using Cable Glands . . . . . . . . . 2-9

Using Conduit Entries . . . . . . . 2-10

Instantiation, Block . . . . . . . . . . . . 3-3

Junction Box

Mounting . . . . . . . . . . . . . . . . . . 2-2

LIM_NOTIFY . . . . . . . . . . . . . . . . 3-5

Link Active Scheduler . . . . . . . . . . 3-3

Logic Equation Syntax . . . . . . . . . D-1

Error Handling . . . . . . . . . . . . . D-4

Logic Transducer

Parameters . . . . . . . . . . . . . . . . C-8

MAINT_ACTIVE . . . . . . . . . . . . . . 3-7

MAINT_ALARMS . . . . . . . . . . . . . 3-7

MAINT_ACTIVE . . . . . . . . . . . . 3-7

MAINT_ALM . . . . . . . . . . . . . . . 3-7

MAINT_ENABLED . . . . . . . . . . 3-7

MAINT_MASK . . . . . . . . . . . . . 3-7

MAINT_PRI . . . . . . . . . . . . . . . 3-7

MAINT_ALM . . . . . . . . . . . . . . . . . 3-7

MAINT_ENABLED . . . . . . . . . . . . 3-7

MAINT_MASK . . . . . . . . . . . . . . . 3-7

MAINT_PRI . . . . . . . . . . . . . . . . . 3-7

Maintenance

Hardware . . . . . . . . . . . . . . . . . 4-2

Communication Check . . . . 4-2

Power Check . . . . . . . . . . . 4-2

Reset Configuration . . . . . . 4-2

Sensor Check . . . . . . . . . . . 4-2

Material Return . . . . . . . . . . . . . . . 1-3

MAX_NOTIFY . . . . . . . . . . . . . . . . 3-5

LIM_NOTIFY . . . . . . . . . . . . . . 3-5

MODE_BLK.TARGET . . . . . . . . . . 3-2

MODE_BLOCK.ACTUAL . . . . . . . 3-2

Modes

Changing Modes . . . . . . . . . . . . 3-2

Permitted Modes . . . . . . . . . . . . 3-2

Types of Modes . . . . . . . . . . . . 3-2

Auto . . . . . . . . . . . . . . . . . . . 3-2

Man . . . . . . . . . . . . . . . . . . . 3-2

Other . . . . . . . . . . . . . . . . . . 3-2

Out of Service . . . . . . . . . . . 3-2

Motor Control . . . . . . . . . . . . . . . . E-1

Mounting . . . . . . . . . . . . . . . . . . . . 2-1

2-Inch Pipe Stand . . . . . . . . . . . 2-3

DIN Rail Without an Enclosure . 2-2

Panel with a Junction Box . . . . . 2-2

Multiple Discrete Input Blocks . . C-12,

C-13

Multiple Discrete Output Blocks .C-13

Parameters . . . . . . . . . . . . . . .C-14

Network Parameters . . . . . . . . . . . 3-4

Operation . . . . . . . . . . . . . . . . . . . 3-1

Ordering Information . . . . . . . . . . . A-7

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

Manual . . . . . . . . . . . . . . . . . . . 1-2

Transmitter . . . . . . . . . . . . . . . . 1-2

Parameter

ADVISE_ACTIVE . . . . . . . . . . . 3-8

ADVISE_ALM . . . . . . . . . . . . . . 3-8

ADVISE_ENABLED . . . . . . . . . 3-7

ADVISE_PRI . . . . . . . . . . . . . . . 3-7

DEFINE_WRITE_LOCK . . . . . . 3-5

FAILED_ACTIVE . . . . . . . . . . . 3-6

FAILED_ALARMS . . . . . . . . . . . 3-6

FAILED_ALM . . . . . . . . . . . . . . 3-6

FAILED_ENABLED . . . . . . . . . . 3-6

FAILED_MASK . . . . . . . . . . . . . 3-6

FAILED_PRI . . . . . . . . . . . . . . . 3-6

FEATURES . . . . . . . . . . . . . . . . 3-4

FEATURES_SEL . . . . . . . . . . . 3-5

LIM_NOTIFY . . . . . . . . . . . . . . . 3-5

MAINT_ACTIVE . . . . . . . . . . . . 3-7

MAINT_ALARMS . . . . . . . . . . . 3-7

MAINT_ALM . . . . . . . . . . . . . . . 3-7

MAINT_ENABLED . . . . . . . . . . 3-7

MAINT_MASK . . . . . . . . . . . . . 3-7

MAINT_PRI . . . . . . . . . . . . . . . . 3-7

MAX_NOTIFY . . . . . . . . . . . . . . 3-5

MODE_BLK.TARGET . . . . . . . . 3-2

MODE_BLOCK_ACTUAL . . . . . 3-2

Network . . . . . . . . . . . . . . . . . . . 3-4

RECOMMENDED_ACTION . . . 3-8

REPORTS . . . . . . . . . . . . . . . . 3-4

UNICODE . . . . . . . . . . . . . . . . . 3-4

WRITE_LOCK . . . . . . . . . . . . . . 3-5

Parameters . . . . . . . . . . . . . . . . .C-13

Discrete Input . . . . . . . . . . . . .C-10

Discrete Output . . . . . . . . . . . .C-12

I/O Transducer . . . . . . . . C-1, C-5

Logic Transducer . . . . . . . . . . .C-8

Multiple Discrete Input . . . . . .C-13

Multiple Discrete Output . . . . .C-14

Permitted Modes . . . . . . . . . . . . . . 3-2

Physical

Specifications . . . . . . . . . . . . . .A-4

PlantWeb Alarms . . . . . . . . . . 3-6, 3-8

Advisory . . . . . . . . . . . . . . . . . . 3-7

FAILED_ALARMS . . . . . . . . . . . 3-6

MAINT_ALARMS . . . . . . . . . . . 3-7

Recommended Actions . . . . . . . . . 3-8

PlantWeb Alarms . . . . . . . . . . . 3-8

RECOMMENDED_ACTION . . . . . 3-8

Reports . . . . . . . . . . . . . . . . . . . . . 3-4

Resource Block . . . . . . . . . . . . . . . 3-4

Configuration . . . . . . . . . . . . . . . 3-4

FEATURES, FEATURES_SEL .3-4

Parameters . . . . . . . . . . . . . . . .C-1

Troubleshooting . . . . . . . . . . . . 4-3

Return of Materials . . . . . . . . . . . . 1-3

Security . . . . . . . . . . . . . . . . . . . . . 3-5

Security Switch . . . . . . . . . . . . . . . 2-6

Senor

Connection Check . . . . . . . . . . . 4-2

Sensor

Tag . . . . . . . . . . . . . . . . . . . . . . 2-8

Simulate Enable Switch . . . . . . . . . 2-6

Soft W Lock, Hard W Lock . . . . . . 3-5

Specifications

Function Block . . . . . . . . . . . . .A-4

Functional . . . . . . . . . . . . . . . . .A-1

Physical . . . . . . . . . . . . . . . . . . .A-4

Surges . . . . . . . . . . . . . . . . . . . . . . 2-5

Switches . . . . . . . . . . . . . . . . . . . . 2-5

Security . . . . . . . . . . . . . . . . . . . 2-6

Simulate Enable . . . . . . . . . . . . 2-6

Reference Manual

00809-0100-4696, Rev AA

9/17/04

Index-3

Rosemount 848L

Tagging . . . . . . . . . . . . . . . . . . . . . 2-8

Commissioning . . . . . . . . . . . . . 2-8

Sensor . . . . . . . . . . . . . . . . . . . 2-8

Transmitter . . . . . . . . . . . . . . . . 2-8

Timer Recommendations, Host . . 3-4

Transients . . . . . . . . . . . . . . . . . . . 2-5

Transmitter

Tag . . . . . . . . . . . . . . . . . . . . . . 2-8

Troubleshooting . . . . . . . . . . . . . . 4-3

Foundation Fieldbus . . . . . . . . . 4-3

Resource Block . . . . . . . . . . . . 4-3

Types of Modes

Auto . . . . . . . . . . . . . . . . . . . . . 3-2

Man . . . . . . . . . . . . . . . . . . . . . 3-2

Other Types of Modes . . . . . . . 3-2

Out of Service . . . . . . . . . . . . . . 3-2

Unicode . . . . . . . . . . . . . . . . . . . . 3-4

Valve Control . . . . . . . . . . . . . . . . F-1

Alarms . . . . . . . . . . . . . . . . . . . F-2

Boolean Expressions . . . . . . . . F-3

Virtual Communication Relationship

(VCRs) . . . . . . . . . . . . . . . . . . . . . 3-4

Network Parameters . . . . . . . . . 3-4

Wiring . . . . . . . . . . . . . . . . . . . . . . 2-4

Communication Check . . . . . . . 4-2

Diagram . . . . . . . . . . . . . . . . . . A-6

Power Check . . . . . . . . . . . . . . 4-2

Reference Manual

00809-0100-4696, Rev AA

9/17/04

Rosemount 848L

Index-4

Emerson Process Management

¢00809-0100-4697F¤

Rosemount and the Rosemount logotype are registered trademarks of Rosemount Inc.

PlantWeb is a registered trademark of one of the Emerson Process Management group of companies.

All other marks are the property of their respective owners.

Reference Manual

00809-0100-4696, Rev AA

September 2004

Rosemount Temperature GmbH

Frankenstrasse 21

63791 Karlstein

Germany

T 49 (6188) 992 0

F 49 (6188) 992 112

Emerson Process Management Asia

Pacific Private Limited

1 Pandan Crescent

Singapore 128461

T (65) 6777 8211

F (65) 6777 0947

AP.RMT-Specialist@emersonprocess.com

Rosemount Inc.

8200 Market Boulevard

Chanhassen, MN 55317 USA

T (U.S.) 1-800-999-9307

T (International) (952) 906-8888

F (952) 949-7001

www.rosemount.com

Emerson 848L Users Manual Logic Transmitter With FOUNDATION Fieldbus

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