Allen-Bradley 1747 DCM Direct Communication Module User Manual

Allen-Bradley

Direct

Communication

Module

(Cat. No. 1747-DCM)

User

Manual

Important User Information

Solid state equipment has operational characteristics differing from those of electromechanical equipment. “Safety Guidelines for the Application,

Installation and Maintenance of Solid State Controls” (Publication SGI-1.1) describes some important differences between solid state equipment and hard-wired electromechanical devices. Because of this difference, and also because of the wide variety of uses for solid state equipment, all persons responsible for applying this equipment must satisfy themselves that each intended application of this equipment is acceptable.

In no event will the Allen-Bradley Company be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and requirements associated with any particular installation, the Allen-Bradley Company cannot assume responsibility or liability for actual use based on the examples and diagrams.

No patent liability is assumed by Allen-Bradley Company with respect to use of information, circuits, equipment, or software described in this manual.

Reproduction of the contents of this manual, in whole or in part, without written permission of the Allen-Bradley Company is prohibited.

Throughout this manual we use notes to make you aware of safety considerations.

!

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

Attentions help you:

• identify a hazard

• avoid the hazard

• recognize the consequences

Important: Identifies information that is especially important for successful application and understanding of the product.

PLC, PLC-2, PLC-3, and PLC-5 are registered trademarks of Allen-Bradley Company, Inc.

SLC, SLC 500, Dataliner, PanelView, RediPANEL, PLC-5/11, PLC-5/15, PLC-5/20, PLC-5/12,

PLC-5/25, PLC-5/30, PLC-5/40, PLC-5/60 are trademarks of Allen-Bradley Company, Inc.

IBM is a registered trademark of International Business Machines, Incorporated.

New Information

Summary of Changes

Summary of Changes

The information below summarizes the changes to this manual since the last printing as 1747-NM007–September 1993.

To help you find new information and updated information in this release of the manual, we have included change bars as shown to the right of this paragraph.

The table below lists sections that document new features and additional information about existing features, and shows where to find this new information.

For This New Information

Related documentation updated

Quick Start for Experienced Users

Default DIP switch settings

CE certification

DCM clear on fault DIP switch

See

preface chapter 2 chapter 4 chapter 5, appendix A chapter 6

Overview

Quick Start for Experienced Users

Addressing

Module Configuration

Table of Contents

Direct Communication Module

User Manual

Preface

Who Should Use this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Purpose of this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents of this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Terms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Common Techniques Used in this Manual . . . . . . . . . . . . . . . . . . . . . . . . . .

Allen-Bradley Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Local Product Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Technical Product Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your Questions or Comments on this Manual . . . . . . . . . . . . . . . . . . . . .

P–1

P–1

P–2

P–2

P–4

P–5

P–5

P–5

P–5

P–5

Chapter 1

Hardware Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

What Is a Remote I/O Adapter?

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Extended Node Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scanner Image Division . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scanner Image Division Configuration Example . . . . . . . . . . . . . . . . . . .

Data Exchange Between RIO Scanners and the DCM . . . . . . . . . . . . . . . . .

What Is the Status Word?

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1–4

1–5

1–6

1–6

1–1

1–2

1–2

1–4

Chapter

2

Required Tools and Equipment

Procedures

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2–1

2–2

Chapter 3

Addressing Ladder Logic Instructions

PLC/Scanner Addresses

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SLC Addresses

I/O Image Tables

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PLC to DCM/SLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DCM/SLC to PLC

Image Mapping

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–1

3–2

3–3

3–4

3–4

3–4

3–5

Chapter 4

DIP Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DIP Switch 1 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Starting I/O Group Number (SW1-7 and SW1-8) . . . . . . . . . . . . . . . . . . .

Rack Address (SW1-1 through SW1-6) . . . . . . . . . . . . . . . . . . . . . . . . .

DIP Switch 2 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Rack Size (SW2-5 and SW2-6))

Last Rack (SW2-4)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Clear On Fault (SW2-3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Data Rate (SW2-1 and SW2-2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4–6

4–6

4–7

4–7

i

4–1

4–2

4–2

4–3

4–6

ii

Table of Contents

Direct Communication Module

User Manual

Installation and Wiring

Programming

Troubleshooting

Application Examples

Chapter 5

Compliance to European Union Directives

EMC Directive

. . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DCM Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Installation

Removal

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Network Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5–1

5–1

5–1

5–2

5–2

5–3

Chapter 6

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Physical Input into PLC – Physical Output from SLC . . . . . . . . . . . . . . . .

Physical Input into SLC – Physical Output from PLC . . . . . . . . . . . . . . . .

Physical Input into Both PLC and SLC (Logical AND) –

Physical Output from SLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Physical Input into First SLC – Physical Output from Second SLC

Status Words

. . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RIO Scanner Input Status Word Examination (Decimal)

DCM/SLC Output Status Word Examination (Octal)

. . . . . . . . . . . . .

. . . . . . . . . . . . . . . .

Applications Using I/O Status Word Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RIO Scanner Status Word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the Program/Test/Fault Mode Bit . . . . . . . . . . . . . . . . . . . . . . .

DCM/SLC Output Status Word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the Data Invalid Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the User Status Flag Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RIO Scanner Input Status and DCM/SLC Output Status . . . . . . . . . . . . .

Using the Logical OR Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–7

6–7

6–7

6–7

6–8

6–10

6–10

6–3

6–4

6–5

6–5

6–6

6–7

6–1

6–2

6–2

6–3

Chapter 7

DCM Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting Using the FAULT LED (Red) . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting Using the COMM LED (Green) . . . . . . . . . . . . . . . . . . . . . .

7–1

7–1

7–2

Chapter 8

Basic Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1747-SN Module Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DIP Switch Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Configuration for Rack 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Configuration for Rack 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Image Table Configuration

Program Listing

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Supplementary Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Module Configuration

DIP Switch Settings

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Image Table Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–3

8–3

8–4

8–4

8–5

8–5

8–5

8–1

8–1

8–2

8–2

8–2

Specifications

DCM Addressing

Worksheet

Table of Contents

Direct Communication Module

User Manual

Program Listing for 5/01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Program Listing for PLC5/15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–6

8–9

Appendix A

Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Network Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Throughput Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1

A–1

A–1

A–2

Appendix B

Directions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Addressing Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PLC Addresses

SLC Addresses

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B–1

B–1

B–1

B–1

iii

Preface

Who Should Use this

Manual

Purpose of this Manual

Preface

Read this preface to familiarize yourself with the rest of the manual. This preface covers the following topics:

• who should use this manual

• the purpose of this manual

• terms and abbreviations

• conventions used in this manual

•

Allen–Bradley support

Use this manual if you are responsible for designing, installing, programming, or troubleshooting control systems that use Allen–Bradley small logic controllers.

You should have a basic understanding of SLC 500 t products. You should understand programmable controllers and be able to interpret the ladder logic instructions required to control your application. If you do not, contact your local Allen–Bradley representative for information on available training courses before using this product. If using Advanced Programming

Software (APS), we recommend that you review The APS Quick Start for

New Users, Publication 9399-APSQS.

This manual is a reference guide for the Direct Communication Module

(DCM). It describes the procedures you use to address, configure and program the DCM for application with PLCs and SLCs.

P–1

Preface

Contents of this Manual

Chapter

1

Title

Preface

Overview

Content

Describes the purpose, background, and scope of this manual. Also specifies the audience for whom this manual is intended.

Provides a hardware and system overview including physical features, system communication, scanner image division and communications flow.

2

3

4

5

6

7

8

Appendix A

Quick Start for Experienced Users

Addressing

Module Configuration

Installation and Wiring

Programming

Troubleshooting

Application Examples

Specifications

Appendix B

DCM Addressing Worksheet

Serves as a Quick Start Guide for using the DCM.

Explains slot numbering and image mapping.

Provides DIP switch setting information.

Provides installation procedures and a wiring diagram.

Shows how to program ladder logic in the PLC r and the SLC 500, including an examination of special programming instructions that affect system response. Also examines the status word and its applications.

Describes troubleshooting using front panel LEDs.

Provides and examines both basic and supplementary applications.

Provides module and system specifications and discusses throughput.

Helps you to work out the image table configuration for DCMs in your system.

P–2

Preface

Related Documentation

The following documents contain additional information concerning

Allen–Bradley SLC t and PLC products. To obtain a copy, contact your local Allen–Bradley office or distributor.

For

An overview of the SLC 500 family of products

A description on how to install and use your Fixed SLC 500 programmable controller

A description on how to install and use your Modular SLC 500 programmable controller

A reference manual that contains information regarding the use of the PLC–5 r programmable controller

A procedural manual for technical personnel who use APS to develop control applications

A reference manual that contains status file data, and instruction set information for the SLC 500 processors and MicroLogix 1000 controllers.

Information regarding the use of the 1747–SN SLC RIO scanner

An introduction to APS for first–time users, containing basic concepts but focusing on simple tasks and exercises, and allowing the reader to begin programming in the shortest time possible

Read This Document

SLC 500 System Overview

Installation & Operation Manual for Fixed Hardware

Style Programmable Controllers

Installation & Operation Manual for Modular

Hardware Style Programmable Controllers

PLC–5 Reference Instruction Set

Rockwell Software Advanced Programming

Software (APS) User Manual

SLC 500 t and MicroLogix 1000t Instruction Set

Reference Manual

Remote I/O Scanner User Manual

Quick Start for New Users

Document

Number

1747-2.30

1747-6.21

1747-6.2

1785-6.1

9399-APSUM

1747-6.15

1747-6.6

9399-APSQS

A training and quick reference guide to APS

A common procedures guide to APS.

A procedural and reference manual for technical personnel who use an HHT to develop control applications

An introduction to HHT for first–time users, containing basic concepts but focusing on simple tasks and exercises, and allowing the reader to begin programming in the shortest time possible

SLC 500 Software Programmer’s Quick Reference

Guide

 available on PASSPORT at a list price of

$50.00

SLC 500 Common Procedures Guide

 available on

PASSPORT at a list price of $50.00

Allen–Bradley Hand–Held Terminal User Manual

Getting Started Guide for HHT

ABT-1747-TSG001

ABT-1747-TSJ50

1747-NP002

1747-NM009

An article on wire sizes and types for grounding electrical equipment

National Electrical Code

Published by the

National Fire

Protection

Association of

Boston, MA.

A complete listing of current Allen–Bradley documentation, including ordering instructions. Also indicates whether the documents are available on CD–ROM or in multi–languages.

A glossary of industrial automation terms and abbreviations

Allen–Bradley Publication Index

Allen–Bradley Industrial Automation Glossary

SD499

AG-7.1

P–3

Preface

Terms and Abbreviations

The following terms and abbreviations are specific to this product. For a complete listing of Allen–Bradley terminology, refer to the Allen–Bradley

Industrial Automation Glossary, Publication Number ICCG–7.1.

Adapter – Any physical device that is a slave on the RIO link.

Adapter Image – The portion of scanner image assigned to an individual adapter. You configure the adapter image by assigning it a starting logical rack number, starting logical group number and the number of logical groups it uses. In the case of the DCM, this is referred to as the DCM image.

DCM – Refers to the Direct Communication Module.

Distributed Control/Controller – Refers to a control system that employs a number of different hardware controllers/processors, each designed to perform a different subtask on behalf of an overall program or process. In a single processor (non–distributed) system, each task would be done by the single processor controlling the process. In a distributed system, each task is targeted to the specific processor required to perform its needs. Since all processors run simultaneously and independently, the time required to perform each task of the overall process is reduced in comparison to a single processor system. Therefore, overall program or process performance is typically better.

Inhibit – A function by which the scanner stops communicating with a logical device. The logical device will consider itself inhibited if it does not receive communications from the scanner within a certain period of time.

Logical Device – Any portion of a logical rack assigned to a single adapter.

Logical Group – A logical group consists of one input and one output word within a logical rack. A word consists of 16 bits, each bit represents one terminal on a discrete I/O module. Also referred to as an I/O Group.

Logical Rack – A fixed section of the scanner image comprised of eight input words and eight output words. Also referred to as a rack.

Logical Slot – A logical slot consists of one input and one output byte within a logical group. A byte consists of 8 bits, each bit represents one terminal on a discrete I/O module.

Physical Device – The number of devices that the supervisory processor/ scanner will support.

PLC Chassis – A physical PLC (Programmable Logic Controller) rack that houses PLC processors and 1771 I/O modules.

P–4

Preface

Rack Size – The logical rack size of the DCM image.

RIO Link – (Remote Input/Output) Refers to an Allen–Bradley communication system supporting high–speed serial transfer of Remote I/O

(RIO) control information.

Scanner – The communication master on the RIO link.

Scanner Image – The data table area within the scanner, used to exchange

I/O information between the scanner and all the adapters on the RIO link.

The scanner image is a portion of the SLC or PLC processor image.

Slave – In a communication link, a station that cannot initiate communication.

SLC Chassis – A physical SLC (Small Logic Controller) rack that houses

SLC processors and 1746 and 1747 I/O modules.

Slot – The physical location in any chassis used to insert I/O (or specialty) modules.

Supervisory Control/Controller – A control system whereby a host

(supervisory) controller/processor monitors and intermittently adjusts control parameters, as necessary, of one or several lower level processors while the lower level processor(s) performs the control task continuously in real time.

Common Techniques Used in this Manual

The following conventions are used throughout this manual:

•

Bulleted lists such as this one provide information, not procedural steps.

•

Numbered lists provide sequential steps or hierarchical information.

•

Italic type is used for emphasis.

P–5

Preface

Allen–Bradley Support

Allen–Bradley offers support services worldwide, with over 75 Sales/Support

Offices, 512 authorized Distributors and 260 authorized Systems Integrators located throughout the United States alone, plus Allen–Bradley representatives in every major country in the world.

Local Product Support

Contact your local Allen–Bradley representative for:

• sales and order support

• product technical training

• warranty support

• support service agreements

Technical Product Assistance

If you need to contact Allen–Bradley for technical assistance, please review the information in the Troubleshooting chapter first. Then call your local

Allen–Bradley representative.

Your Questions or Comments on this Manual

If you find a problem with this manual, please notify us of it on the enclosed

Publication Problem Report.

If you have any suggestions for how this manual could be made more useful to you, please contact us at the address below:

Allen–Bradley Company, Inc.

Automation Group

Technical Communication, Dept. 602V, T122

P.O. Box 2086

Milwaukee, WI 53201–2086

P–6

Chapter

1

Overview

This chapter provides a hardware and system overview including physical features and connectivity illustrations. It also explains data exchange between processors and discusses rack size. Topics include:

• hardware overview

• system overview

• scanner image division

• communications flow

Hardware Overview

FAULT LED

(Red)

COMM LED

(Green)

Door Label

Front Label

RIO Link Connector

Cable Tie Slots

The Direct Communication Module, Catalog Number 1747–DCM, is used to connect an SLC 500 Fixed Programmable Controller with expansion chassis or any SLC 500 Modular Programmable Controller to a supervisory

Allen–Bradley Programmable Controller via the RIO Link, thereby providing a distributed processing system. The DCM occupies one slot in any SLC 500 chassis.

Self–Locking Tab

Side Label

DIP Switches

DCM

FAULT

COMM

CONFIGURATION

RACK ADDR

RACK SIZE

1/4 1/2 3/4 1

FIRST I/O GROUP

0 2 4 6

DATA RATE (K B/S)

57.6 115.2 230.4

LINE 1 _______

SHIELD ______

LINE 2 _______

I/O

GROUP

(LSB)

RACK

ADDRESS

(MSB)

X

X

RACK

SIZE

LAST RACK

CLR ON FLT

DATA

RATE

SW 1

(LSB)

RACK

ADDR

(MSB)

2

1

4

3

6

5

8

7

SW 2

X

X

LAST RACK

CLR ON FLT

DATA

RATE

2

1

4

3

6

5

8

7

1747–DCM

Self–Locking Tab

Hardware Features

Hardware

FAULT LED

COMM LED

Front, Side and Door Labels

RIO Link Connector

Cable Tie Slots

DIP Switches

Self–Locking Tabs

Displays operating status

Function

Displays communication status

Provide module configuration information

Provides physical connection to RIO network

Secure and route wiring from module

Establish configuration parameters for the module

Secure module in chassis slot

1–1

Chapter 1

Overview

System Overview

Supervisory PLC or SLC

The Direct Communication Module is an SLC 500 family Remote I/O (RIO) adapter. It allows supervisory processors, such as PLC–5s, and distributed

SLC–500 processors residing on an Allen–Bradley RIO Communication

Link to transfer data between each other. The DCM appears as an RIO adapter to:

• a PLC processor with integral RIO scanner on the RIO Communication

Link

• an RIO scanner, Catalog Number 1771–SN or 1747–SN, on the RIO

Communication Link

DCM 1

RIO Scanner Distributed SLCs with

DCMs (adapters)

PanelView t (adapter)

DCM 2

DCM 3

RIO Communication Link

DCM modules are connected in a daisy–chain configuration using Belden

9463 cable.

What Is a Remote I/O Adapter?

A remote I/O adapter (RIO adapter) is any module that acts as a slave to an

RIO scanner, the master on the RIO link. The DCM is an RIO adapter.

All RIO scanners have defined physical and logical specifications. Physical

specifications are the maximum number of adapters that can be connected to

the scanner. (See Extended Node Capability on page 1–4.) Logical

specifications are the maximum number of logical racks the scanner can address, the ways logical racks can be assigned, and the ability of the scanner to perform block transfers. Refer to the appropriate scanner manual for details concerning physical and logical specifications.

The DCM can physically reside on the RIO link with any other adapter. The following table lists the adapters available for use with an RIO link.

1–2

Chapter 1

Overview

1784-F30D

1771-RIO

1771-JAB

1771-DCM

1778-ASB

1747-ASB

2706-xxxx

2705-xxx

2711-xx

1336-RIO

Compatible Adapters

Catalog

Number

1785-LT/x

1785-LT2

1785-LT3

1785-L30x

1785-L40x

1785-L60x

1771-ASC

1771-ASB

Device

PLC-5/15

PLC-5/25

PLC-5/12

PLC-5/30

PLC-5/40

PLC-5/60

Remote I/O Adapter Module

Remote I/O Adapter Module

1771-AM1

1771-AM2

1395-NA

1747-ASB

1-Slot I/O Chassis with Integral

Power Supply and Adapter

2-Slot I/O Chassis with Integral

Power Supply and Adapter

Plant Floor Terminal Remote I/O

Expansion Module

Remote I/O Interface Module

Single Point I/O Adapter Module

Direct Communication Module

Remote I/O Adapter Module

Remote I/O Adapter Module

DL40 Dataliner t

RediPANEL t

PanelView Terminal

Remote I/O Adapter for 1336 AC

Industrial Drives

Remote I/O Adapter for 1395 DC

Industrial Drives

SLC 500 Remote I/O Adapter

Module

Yes

No

Yes

No

Yes

Yes

Yes

Yes

Yes

Yes

Extended

Node

Capability

Yes

Yes

Yes

Yes

Yes

Yes

No

Series B and

C only

Comments

In adapter mode

In adapter mode

In adapter mode

In adapter mode

In adapter mode

In adapter mode

Series A, B, and C

Yes

Yes

Yes

Yes

Must be catalog number

2706-ExxxxxB1.

1–3

Chapter 1

Overview

Scanner Image Division

Extended Node Capability

Both scanners and adapters can have extended node capability. Extended node capability allows you to have up to 32 adapters on the RIO link using an 82 Ohm termination resistor at both ends of the RIO link for all baud rates.

Extended node capability can only be used if the scanner and all adapters on the RIO link have extended node capability. The DCM has extended node

capability.

The scanner allows each adapter to use a fixed amount (user defined) of its input and output image.

The scanner image is divided into logical racks and further divided into logical groups. A full logical rack consists of eight input and eight output image words. A logical group consists of one input and one output word in a logical rack. Each logical group is assigned a number from 0–7. The number of racks available for data and I/O transfer depends on the scanner you are using.

Local I/O

Logical Rack 0

Logical Rack 1

Remote I/O

(Scanner Image)

Logical Rack 2

Logical Rack 3

Logical Group 0

Logical Group 7

Scanner I/O Image Processor I/O Image Adapter

Image

The scanner image also contains the image of each adapter on the RIO link.

The adapter is assigned a portion of the scanner image, which is referred to as the adapter image.

1–4

Chapter 1

Overview

Scanner Image Division Configuration Example

The example presented here can help you configure your RIO architecture.

Refer to it as necessary.

The following figure shows how a portion of a scanner’s input image table might be configured. An output image table would be identically configured.

Logical

Rack 0

Logical

Rack 1

Logical

Rack 2

Decimal Bit Number

Rack 0 Group 0

Rack 0 Group 1

Rack 0 Group 2

Rack 0 Group 3

Rack 0 Group 4

Rack 0 Group 5

Rack 0 Group 6

Rack 0 Group 7

Rack 1 Group 0

Rack 1 Group 1

Rack 1 Group 2

Rack 1 Group 3

Rack 1 Group 4

Rack 1 Group 5

Rack 1 Group 6

Rack 1 Group 7

Rack 2 Group 0

Rack 2 Group 1

Rack 2 Group 2

Rack 2 Group 3

Rack 2 Group 4

Rack 2 Group 5

Rack 2 Group 6

Rack 2 Group 7

Octal Bit Number

Word 11

Word 12

Word 13

Word 14

Word 15

Word 16

Word 17

Word 18

Word 19

Word 20

Word 21

Word 22

Word 23

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

Word 8

Word 9

Word 10

15

17

14

16

13

15

12

14

11

13

10

12

9

11

8

10

7

7

6

6

5

5

4

4

3

3

2

2

1

1

0

0

Device 1

(Full logical rack)

Device 2

(3/4 logical rack)

Device 3

(1/4 logical rack)

Device 4

(1/2 logical rack)

Device 5

(1/2 logical rack)

Important: The configured image size of a DCM cannot cross logical rack boundaries; it cannot use a portion of rack 0 and a portion of rack 1.

1–5

Chapter 1

Overview

Data Exchange Between RIO

Scanners and the DCM

Processor Scan

Supervisory PLC or SLC

Information is transferred between the RIO scanner and the DCM every RIO scan. RIO transmissions are asynchronous to the processor scans.

Important: The DCM provides word integrity on all words transferred via the SLC backplane.

The DCM communicates with supervisory PLC or SLC controllers through

RIO scanners, as if they were addressing a logical rack. However, the DCM does not scan the I/O in its local I/O chassis, rather it passes the supervisory data to the distributed SLC processor.

In the DCM, outputs from the SLC output image table are inputs to the supervisory processor input image table. Likewise, outputs from the supervisory processor output image table are inputs to the SLC input image table.

The diagram that follows depicts the communications flow between an RIO scanner and the DCM.

Distributed Processor Scan

SLC Distributed

Processor

DCM I/O Module I/O Module

Scanner

RIO Scan

Outputs from PLC,

Input Data to DCM

Inputs to PLC, Output

Data from DCM

SLC Chassis

Inputs to Modules

SLC Expansion

Chassis

Outputs from

Modules

Output Device

Input Device

What Is the Status Word?

The first word of the DCM input and output image is the status word. The status word indicates the status of communication and data between the RIO scanner and the DCM. For more information on status words and their

applications, see chapter 6, Programming.

1–6

Required Tools and

Equipment

Chapter

2

Quick Start for Experienced Users

This chapter helps you to get started using the Direct Communication

Module (DCM). We base the procedures here on the assumption that you have a basic understanding of SLC 500 products.

You must:

• understand electronic process control

• be able to interpret the ladder logic instructions for generating the electronic signals that control your application

Because it is a start-up guide for experienced users, this chapter does not contain detailed explanations about the procedures listed. It does, however, reference other chapters in this book where you can get more detailed information. It also references other documentation that may be helpful if you are unfamiliar with programming techniques or system installation requirements.

If you have any questions, or are unfamiliar with the terms used or concepts presented in the procedural steps, always read the referenced chapters and other recommended documentation before trying to apply the information.

This chapter:

• tells you what tools and equipment you need

• lists preliminary considerations

• describes when to address, configure and program the module

• explains how to install and wire the module

• discusses system power-up procedures

Have the following tools and equipment ready:

• medium blade screwdriver

•

(2) 1/2 watt terminating resistors (See chapter 5, Installation and Wiring,

for correct size.)

• programming equipment (All programming examples shown in this manual demonstrate the use of Allen-Bradley’s Advanced Programming

Software [APS] for personal computers.)

2–1

Chapter 2

Quick Start for Experienced Users

Procedures

1.

Check the contents of the shipping box.

Unpack the module making sure that the contents include:

•

Direct Communication Module (Catalog Number 1747-DCM)

• removable connector (factory-installed on module)

• cable tie

• user manual (Catalog Number 1747-NM007)

If the contents are incomplete, call your local Allen-Bradley representative for assistance.

Reference

–

Select a scanner.

Reference

To begin configuration of your RIO system, you should know three things:

• which scanner is compatible with your PLC/SLC controller. Use the table below to select a scanner that is compatible with your processor. The DCM is compatible with all RIO scanners.

The manual for the scanner you select

1747-SN

➀

Catalog Number

1771-SN

➁

1772-SD, -SD2

➂➃

1775-S4A, -S4B, -S5

➀

1775-SR, -SR5

➀

1785-L11B

➀

1785-LT/x

➀➄

1785-L20B

➀

1785-LT2

➀➄

1785-L30x

➀

1785-L40x

➀

1785-L60x

➀

5250-RS

➀

6008-SI

➀

6008-SV

➀

6008-SQH1, -SQH2

Description

SLC Remote I/O Scanner

Sub I/O scanner for Mini–PLC-2 r

and PLC-5 families

Remote scanner/distribution panel for PLC-2 family

I/O scanner-programmer interface module for PLC-3 r

family

Remote scanner/distribution panel for PLC-3/10 family

PLC 5/11 t (in scanner mode)

PLC 5/15 (in scanner mode)

PLC 5/20 t (in scanner mode)

PLC 5/25 (in scanner mode)

PLC 5/30 t (in scanner mode)

PLC 5/40 t (in scanner mode)

PLC 5/60 t (in scanner mode)

Remote scanner for PLC 5/250

IBM r PC I/O Scanner Module

VMEbus I/O Scanner Module

Q-bus I/O Scanner Module

➀

Extended node capability.

➁

Revision D or later.

➂

Rev. 3 or later.

➃

Extended node capability not available with Series A.

➄

Rev. 3 or later.PLC 5/15 Series B Revision H or later have partial rack addressing. Earlier versions are limited to 3 devices.

PLC 5/25 Series A Revision D or later have partial rack addressing. Earlier versions are limited to 7 devices.

2–2

Chapter 2

Quick Start for Experienced Users

• the maximum number of physical devices and logical racks your scanner supports.

• the logical rack size of each DCM. This depends on how many I/O data words you need to transfer. The first word is always the status word. The table below shows the number of data words transferred relative to the rack size.

If you configure the DCM as:

1/4 Rack

1/2 Rack

3/4 Rack

Full Rack

Then:

1 data word (16 bits of I/O data) are transferred.

3 data words (48 bits of I/O data) are transferred.

5 data words (80 bits of I/O data) are transferred.

7 data words (112 bits of I/O data) are transferred.

Including the Status Word

Total transfer = 2 words

Total transfer = 4 words

Total transfer = 6 words

Total transfer = 8 words

3.

Choose the type of slot addressing you will use.

Select DCM addressing. (A configuration worksheet is included in appendix B to assist you in DCM

image table addressing.)

4.

Configure your system by setting the DIP switches.

5.

Configure the module using the DIP switches.

Insert the 1747-DCM module into the chassis.

Reference

Chapter 3

(Addressing)

Appendix B

(DCM Worksheet)

Reference

Chapter 4

(Module

Configuration)

Reference

!

ATTENTION: Never install, remove, or wire modules with power applied to the chassis or devices wired to the module.

Review SLC/DCM power requirements to ensure your SLC power supply has adequate reserve power.

Make sure system power is off; then insert the DCM into your 1746 chassis. In this example procedure, local slot 1 is selected.

Chapter 5

(Installation and

Wiring)

Card Guide

Cable Tie

...

Module Release

2–3

Chapter 2

Quick Start for Experienced Users

To wire the network, a 1/2 watt terminating resistor must be attached across line 1 and line 2 of the connectors at each end (scanner and last physical device) of the network. The size of the resistor depends on the baud rate and extended node capability, as shown below:

Us n xten e xten e

Capability o e

Baud Rate

57.6K baud

115.2K baud

230.4K baud

57.6K baud

115.2K baud

230.4K baud

Maximum Cable Distance

(Belden 9463)

3048 meters (10,000 feet)

1524 meters (5,000 feet)

762 meters (2,500 feet)

3048 meters (10,000 feet)

1524 meters (5,000 feet)

762 meters (2,500 feet)

Resistor Size

8

W 1

Gr r G

150

W 1/2 Watt

Brown–Green–Brown–Gold

82

W 1/2 Watt

Gray–Red–Black–Gold

6.

Enter your ladder program.

Define the application requirements. Write and enter the ladder logic program.

7.

Go through the system start-up procedure.

Power up your system by performing standard start-up procedures as indicated in your processor manual. No special start-up procedures are required when using the DCM module.

Reference

Chapter 6

(Programming)

Chapter 8

(Application

Examples)

Reference

–

2–4

Addressing Ladder Logic

Instructions

Chapter

3

Addressing

This chapter provides general information about how to address supervisory

PLC and distributed SLC ladder logic instructions. It also illustrates image mapping and provides an example of how a PLC output image is mapped into an SLC input image.

All PLC and SLC processors use 3-part addresses. These three parts include:

• logical rack or physical slot address

• logical group or word address

• bit address

PLC processors use the octal number system for bit addressing. SLC processors use the decimal number system for bit addressing.

PLC Processors/Scanners Address By:

Logical Rack: PLC/scanner input and output images are organized in logical racks, which consist of eight groups.

The rack address does not need to match the SLC slot address.

Logical Group: There are eight logical groups per logical rack, numbered 0–7. One group consists of one input and one output word. Each word is made up of 16 bits.

SLC Processors Address By:

Physical Slot: The slot address is determined by what slot number you place your DCM. SLC slots are numbered 0–30.

The slot address does not need to match the PLC rack address.

Word: One word is 16 bits in size. The number of words used in input and output images varies according to how many you specify in your setup. Words are numbered consecutively beginning with 0.

Logical

Rack

#x

The group number does not need to match the SLC word address.

Bit: PLC bits are numbered octally, from

0 to 7 and 10 to 17.

The bit number does not need to match the SLC bit number

(because SLCs use decimal); however, the position of the bit in the word must be the same.

Octal

Bit Number 17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0

Group 0

Group 1

Group 2

Group 3

Group 4

Group 5

Group 6

Group 7

The word number does not need to match the PLC group number.

Bit: SLC bits are numbered decimally, from 0–15.

The bit number does not need to match the PLC bit number

(because PLCs use octal); however, the position of the bit in the word must be the same.

Decimal

Bit Number 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

Physical

Slot

#x

3–1

Chapter 3

Addressing

PLC/Scanner Addresses

The three parts of the PLC address include the:

• logical rack

• logical group (I/O group)

• bit

PLC Input Address PLC Output Address

I:023/10 O:017/10

I = Input

02 = Logical Rack

3 = I/O Group

10 = Bit (octal)

O = Output

01 = Logical Rack

7 = I/O Group

10 = Bit (octal)

The rack address refers to the logical rack assigned to the DCM in the PLC/ scanner I/O image table. It is selected using switches 1 through 6 of SW1 on the DCM. This address does not need to match the physical slot address of

the DCM. Complete information about DIP switch selection is in chapter 4,

Module Configuration.

The I/O group address refers to the word in the PLC/scanner image table that contains the referenced I/O data bit. The I/O group address does not need to match the word address of the SLC I/O instruction.

The bit address is the bit within the word being addressed. Bits are numbered 0–17 (octal) for the PLC and 0–15 (decimal) for the SLC. The physical position of the bit in the PLC word must match the position of the bit in the SLC word to address the correct bit.

3–2

Chapter 3

Addressing

SLC Addresses

The three parts of the SLC address include the:

• physical slot

• word

• bit

SLC Input Address

I:2.3/8

SLC Output Address

O:1.7/8

I = Input

2 = Physical Slot

3 = Word

8 = Bit (decimal)

O = Output

1 = Physical Slot

7 = Word

8 = Bit (decimal)

The slot address refers to the physical slot (1–30) in the modular SLC chassis or fixed SLC expansion chassis where the DCM is installed. This address does not need to match the logical rack address of the PLC I/O instruction.

The word address refers to the word number (0–7) of the slot being addressed. The maximum number of SLC I/O words that a DCM can be assigned is 8.

The bit address is the bit within the word being addressed. Bits are numbered 0–15 (decimal) for the SLC and 0–17 (octal) for the PLC. Outputs from the SLC output image are inputs to the supervisory processor input image table. Likewise, outputs from the supervisory processor output image table are inputs to the SLC image table.

As noted, if the supervisory processor is a PLC the I/O image bits are octal and SLC bits are decimal. While the addresses are different, the position of the bit in the SLC word must match the position of the bit in the PLC word.

The following diagrams show this relationship.

3–3

Chapter 3

Addressing

I/O Image Tables

PLC to DCM/SLC

DCM/SLC configuration: Logical Rack Address = 1

Physical Slot Number = 1

Logical I/O Group = 0

Full Logical Rack

Decimal

Octal

PLC Output Image Table

15 14 13 12 11 10

17 16 15 14 13 12

9 8

11 10

7 6 5 4 3 2 1 0

7 6 5 4 3 2 1 0

DCM Input Image Table SLC Input Image Table

Decimal

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

Decimal

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

O:011/10 I:1.1/8

O = Output

01 = Logical Rack

1 = Logical I/O Group

10 = Bit (octal)

I = Input

1 = Physical DCM Slot

1 = Word

8 = Bit (decimal)

DCM/SLC to PLC

DCM/SLC configuration: Logical Rack Address = 1

Physical Slot Number = 1

Logical I/O Group = 0

Full Logical Rack

Decimal

Octal

PLC Input Image Table

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0

DCM Output Image Table

Decimal

15 14 13 12 11 10 9 8

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

SLC Output Image Table

7 6 5 4 3 2 1 0

Decimal

15 14 13 12 11 10 9 8

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

7 6 5 4 3 2 1 0

I:016/2 O:1.6/2

I = Input

01 = Logical Rack

6 = Logical I/O Group

2 = Bit (octal)

O = Output

1 = Physical DCM Slot

6 = Word

2 = Bit (decimal)

3–4

Image Mapping

Chapter 3

Addressing

An image map is a diagram showing how the scanner image is mapped into the image of multiple adapters. The following table and illustration show how an example PLC output image is mapped into the image of multiple

SLC processors through the DCM.

PLC Scanner Output Image

O:011/10 Starting Group 0

(Rack 01, Group 1, Bit 10 octal)

O:021/3

Starting Group 0

(Rack 02, Group 1, Bit 3 octal)

O:025/13 Starting Group 2

(Rack 02, Group 5, Bit 13 octal)

To: DCM

→

1

→

→

2

3

SLC Input Image

I:1.1/8

(Slot 1, Word 1, Bit 8 decimal)

I:1.1/3

(Slot 1, Word 1, Bit 3 decimal)

I:2.3/11

(Slot 2, Word 3, Bit 11 decimal)

Each row in the table represents the address of a data bit being transferred from the PLC scanner output image to the SLC input image via three different DCMs. The figure on the next page illustrates this data transfer.

Appendix B contains a worksheet designed to help you work out your DCM

system addressing. Use it if necessary to record I/O addresses.

3–5

Chapter 3

Addressing

Scanner Output Image

Bit Number:

Decimal

Octal

Group 0

Group 1

15 14

17 16

13 12 11 10 9 8 7 6 5 4

15 14 13 12 11 10 7 6 5 4

3

3

2

2

1

1

0

0

Reserved for Status Word

DCM 1

DCM 2

DCM 3

Group 2

Group 3

Group 4

Group 5

Group 6

Group 7

Group 0

Group 1

Group 2

Group 3

Group 4

Group 5

Group 6

Group 7

Reserved for Status Word

Reserved for Status Word

Supervisory SLC or

PLC Processor

O:011/10

(Rack 1, Group 1, Bit 10 Octal)

O:021/2

(Rack 2, Group 1, Bit 3 Octal)

O:025/13

(Rack 2, Group 5, Bit 13 Octal)

RIO Link

Supervisory SLC or PLC

Remote I/O Scanner

SLC 1 Input Image for DCM 1

Bit Number: Decimal

15 14 13 12 11 10 9 8

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

7 6 5 4 3 2 1 0

I:1.1/8

(Slot 1, Word 1, Bit 8 Decimal)

Distributed SLC

Processor 1

DCM 1

Module 1 Configured As:

Rack Address 1

I/O Group 0

Slot Number 1

Rack Size Full

SLC 2 Input Image for DCM 2

15 14 13 12 11 10 9 8

Bit Number: Decimal

7 6 5 4

Reserved for Status Word

Word 0

Word 1

3 2 1 0

I:1.1/3

(Slot 1, Word 1, Bit 3 Decimal)

Distributed SLC

Processor 2

DCM 2

Module 2 Configured As:

Rack Address 2

I/O Group 0

Slot Number 1

Rack Size 1/4

SLC 3 Input Image for DCM 3

Bit Number: Decimal

15 14 13 12 11 10

Word 0

9 8 7 6 5 4

Reserved for Status Word

3 2 1

Word 1

Word 2

Word 3

0

I:1.3/11

(Slot 2, Word 3, Bit 11 Decimal)

Distributed SLC

Processor 3

DCM 3

Module 3 Configured As:

Rack Address 2

I/O Group 2

Slot Number 2

Rack Size 1/2

3–6

DIP Switches

Chapter

4

Module Configuration

This chapter provides DIP switch setting information for the DCM. Topics include:

•

DIP switches

•

DIP switch 1 settings

•

DIP switch 2 settings

To configure the DCM for your application, you must set the DIP switches.

These switches enable the DCM to properly interpret the RIO system addressing. The DCM has two banks of DIP switches mounted on its circuit board. Each bank contains eight switches. The default settings are shown below.

Starting I/O Group Number

Rack Address

SW1

Reserved

Rack Size

Last Rack

Clear On Fault

Data Rate

SW2

DIP Switch 1

(SW1)

DIP Switch 2

(SW2)

4–1

Chapter 4

Module Configuration

DIP Switch 1 Settings

Starting I/O Group Number (SW1-7 and SW1-8)

The starting I/O group number is the first word assigned to the DCM from the scanner’s image table. The starting I/O group number must be an even number from 0 to 6 and is dependent upon whether the DCM has been configured as a full, 3/4, 1/2, or 1/4 rack. The first word transferred is always the status word for the DCM.

Rack Size

1/4 Logical Rack

1/2 Logical Rack

3/4 Logical Rack

Full Logical Rack

Number of RIO Words Transferred

1 Status and 1 Data

1 Status and 3 Data

1 Status and 5 Data

1 Status and 7 Data

Total Words

2

4

6

8

Reference the table below to set the starting I/O group number.

Starting I/O Group Number

0

2

4

6

SW1-7

ON

ON

OFF

OFF

SW1-8

ON

OFF

ON

OFF

Valid Rack Configuration

All

3/4, 1/2, 1/4

1/2, 1/4

1/4

Starting Group 0

Starting Group 2

Starting Group 6

Example of different starting groups:

Bit Number:

Octal

17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0

Decimal

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Group 0, Word 0

Group 1, Word 1

R R S T A T U S W O R D

S T A T U S W O R D

Group 2, Word 2

Group 3, Word 3

Group 4, Word 4

Group 5, Word 5

Group 6, Word 6

Group 7, Word 7

S T A T U S W O R D

DCM 1 Rack Size

= 1/4 Rack

DCM 2 Rack Size

= 1/2 Rack

DCM 3 Rack Size

= 1/4 Rack

In the above image map example, selecting I/O Group Number 2 instructs the scanner to address Word 2 as the beginning of DCM 2 image. In this example, a half rack is selected for DCM 2 (using SW2 switches 5 and 6). Since Word 2 is the first word assigned, it becomes the Status Word.

4–2

Chapter 4

Module Configuration

Rack Address (SW1-1 through SW1-6)

The rack address refers to the logical rack number from the scanner image that contains a particular DCMs image.

The table on page 4–4 gives the switch settings that define possible rack

address choices for all scanners. To use this table, first determine which of the following categories applies to your scanner:

•

PLC-2, mini PLCs, PLC-2/30 with 1772-SD, SD2 remote scanner

•

PLC-3 and PLC-5/250 processors. (This category includes those with built-in scanners, as well as the following without built-in scanners: catalog numbers 1775-54A, -54B, -S5, -SR, -SR5 and 5250-RS.)

•

PLC-5/11, PLC-5/15, PLC-5/20, PLC-5/25, PLC-5/30, PLC-5/40, or

PLC-5/60 and 1771-SN. (This category includes all smaller in-rack processors and standalone scanners that have local and remote I/O and begin rack addressing at rack 1.)

•

SLC-5/02 (or above) with 1747-SN scanner

After determining which category applies to your DCM application:

1. Find the column for the scanner used in your application.

2. Go down the column to the rack address that you assigned to the DCM.

3. Use the switch settings in the right-most columns of the table that correspond to your rack address.

4–3

Chapter 4

Module Configuration

33

34

31

32

26

27

30

23

24

25

20

21

22

40

41

42

43

44

35

36

37

11

12

13

6

7

10

16

17

14

15

3

4

5

1

2

Use this table to set SW1 – switches 1 through 6.

1747-

SN

0

PLC-

2

1

PLC-

3

Logical Rack Number (Octal)

PLC-

5/15

PLC-

5/25

PLC-

5/40

0 – – –

PLC-

5/60

–

PLC-

5/250

0

1

ON

1

2

3

2

3

4

5

6

7

1

2

3 3

4

5

6

7

1

2

11

12

13

6

7

10

16

17

14

15

3

4

5

1

2

11

12

13

6

7

10

16

17

14

15

3

4

5

1

2

23

24

25

26

27

20

21

22

33

34

31

32

26

27

30

35

36

37

23

24

25

20

21

22

11

12

13

6

7

10

16

17

14

15

3

4

5

1

2

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

OFF

OFF

OFF

ON

ON

ON

OFF

OFF

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

2

Switch Number (SW1)

3 4 5

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

ON

ON

ON

OFF

OFF

OFF

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

ON

OFF

OFF

OFF

OFF

ON

ON

OFF

ON

ON

ON

ON

ON

ON

ON

ON

ON

OFF

OFF

OFF

ON

ON

OFF

OFF

OFF

ON

ON

OFF

OFF

OFF

OFF

OFF

ON

ON

ON

ON

ON

ON

ON

ON

ON

OFF

OFF

OFF

ON

ON

OFF

OFF

ON

ON

ON

ON

ON

ON

OFF

OFF

OFF

ON

OFF

ON

ON

ON

OFF

OFF

ON

OFF

OFF

OFF

OFF

ON

ON

ON

ON

OFF

OFF

ON

OFF

OFF

ON

OFF

OFF

ON

OFF

ON

ON

ON

ON

OFF

ON

ON

OFF

ON

OFF

OFF

OFF

ON

ON

OFF

OFF

OFF

OFF

ON

ON

ON

OFF

OFF

ON

ON

OFF

OFF

ON

ON

Continued on next page.

6

OFF

ON

OFF

ON

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

ON

OFF

ON

OFF

ON

OFF

OFF

ON

OFF

ON

OFF

ON

OFF

ON

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

4–4

Chapter 4

Module Configuration

1747-

SN

PLC-

2

77 77

71

72

67

70

64

65

66

61

62

63

56

57

60

73

74

75

76

77

47

50

51

PLC-

3

45

46

54

55

52

53

PLC-

5/15

77

PLC-

5/25

PLC-

5/40

77 77

PLC-

5/60

PLC-

5/250

77 77

5

OFF

ON

ON

OFF

OFF

ON

ON

ON

OFF

ON

OFF

ON

OFF

OFF

OFF

OFF

ON

ON

OFF

OFF

ON

ON

OFF

OFF

ON

ON

3 4

ON

OFF

OFF

OFF

ON

ON

ON

ON

ON

ON

OFF

OFF

ON

OFF

OFF

OFF

OFF OFF

Reserved

ON

OFF

OFF

ON

ON

ON

OFF

OFF

ON

OFF

ON

ON

ON

OFF

OFF

OFF

ON

ON

ON

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

ON

ON

ON

ON

OFF

OFF

2

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

ON

ON

OFF

ON

ON

ON

ON

ON

ON

ON

ON

ON

1

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

OFF

6

OFF

ON

OFF

ON

OFF

ON

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

4–5

Chapter 4

Module Configuration

DIP Switch 2 Settings

Rack Size (SW2-5 and SW2-6)

The logical rack size allocates image space in the scanner for each DCMs I/O data. The DCM allows 1/4, 1/2, 3/4, and full rack addressing. SW2 switches

5 and 6 define the rack size.

Rack Size

1/4 Logical Rack

1/2 Logical Rack

3/4 Logical Rack

Full Logical Rack

SW2-5

ON

ON

OFF

OFF

SW2-6

ON

OFF

ON

OFF

Important: The DCM image cannot cross logical rack boundaries.

Therefore, as an example, configuring the module for 1/2 logical rack with starting group 6 will cause a configuration

error. Refer to Starting I/O Group Number on page 4–2.

Last Rack (SW2-4)

Switch 4 of SW2 must be set to the OFF position if the DCM shares its logical rack with at least one other adapter and has been assigned the highest

I/O group number in that logical rack.

Last Rack

Yes

SW2-4

OFF

No ON

Remote I/O Scanner

Direct Communications Module 1

Module 1 Configured As:

Logical Rack Address 1

I/O Group 0

Module Rack Size 1/4

Logical

Rack 1

Decimal

Bit Number:

Octal

Group 0, Word 0

Module 1

Group 1, Word 1

Module 2

Module 3

Module 4

Group 2, Word 2

Group 3, Word 3

Group 4, Word 4

Group 5, Word 5

Group 6, Word 6

Group 7, Word 7

SLC Output Image (to the PLC)

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0

Module 4 is the last device in the logical rack.

Because Module 4 is the last RIO adapter in a logical rack shared by other adapter(s),

SW2 switch 4 must be in the OFF position.

4–6

Module 2 Configured As:

Logical Rack Address 1

I/O Group 2

Module Rack Size 1/4

Module 3 Configured As:

Logical Rack Address 1

I/O Group 4

Module Rack Size 1/4

Module 4 Configured As:

Logical Rack Address 1

I/O Group 6

Module Rack Size 1/4

Chapter 4

Module Configuration

Clear On Fault (SW2-3)

!

ATTENTION: Before setting SW2-3 to ON, make sure that holding all DCM input bits in their last state, in the event a communication error occurs, does not create an unsafe condition in the distributed SLC processor.

Clear On Fault

Yes

No

SW2-3

OFF

ON

Turn switch to OFF position if you want the DCM to clear and hold clear all data bits in its input image table, in the event of an RIO communication failure or when the supervisory processor enters Program/Test/Fault Mode.

Status bits will not be cleared.

Turn switch to ON position if you want the DCM to hold all input data bits in their last state when an RIO communication failure occurs or when the supervisory processor enters Program/Test/Fault Mode.

Data Rate (SW2-1 and SW2-2)

Data Rate

57.6K baud

115.2K baud b

SW2-1

ON

ON

OFF

OFF

SW2-2

ON

OFF

ON

OFF

Cable Length (Belden 9463)

3048 meters (10,000 feet)

1524 meters (5,000 feet) r f

4–7

Compliance to European

Union Directives

DCM Installation

Chapter

5

Installation and Wiring

This chapter explains how to install the DCM into the SLC chassis and provides information about terminal wiring. Topics include:

•

DCM installation

• network wiring

If this product has the CE mark it is approved for installation within the

European Union and EEA regions. It has been designed and tested to meet the following directives.

EMC Directive

This product is tested to meet Council Directive 89/336/EEC

Electromagnetic Compatibility (EMC) and the following standards, in whole or in part, documented in a technical construction file:

•

EN 50081-2

EMC – Generic Emission Standard, Part 2 – Industrial Environment

•

EN 50082-2

EMC – Generic Immunity Standard, Part 2 – Industrial Environment

This product is intended for use in an industrial environment.

Installation procedures for this module are the same as for any other discrete

I/O or specialty module. Refer to the illustration on page 5–2 to identify

chassis and module components listed in the procedures below.

!

ATTENTION: Disconnect power before attempting to install, remove, or wire the DCM.

Important: Make sure you have set the DIP switches properly before installing the DCM.

Before installation make sure your modular SLC power supply has adequate reserve current capacity. The DCM requires

360mA @ 5 volts. Each Fixed SLC 500 controller can support up to one DCM in a 2-slot expansion chassis, depending on which I/O module is in the second slot. Refer to the Discrete

I/O Modules Product Data, Publication Number 1746-2.35.

5–1

Chapter 5

Installation and Wiring

Installation

1. Disconnect power.

2. Align the full-sized circuit board with the chassis card guides. The first slot (slot 0) of the first rack is reserved for the CPU.

3. Slide the module into the chassis until the top and bottom latches are latched.

4. Attach the RIO link cable to the connector on the front of the module behind the door.

5. Insert the cable tie in the slots.

6. Route the cable down and away from module, securing it with the cable tie.

7. Cover all unused slots with the Card Slot Filler, Catalog Number 1746-N2.

Module Release

Card Guide

...

19627

Cable Tie

Removal

1. Disconnect power.

2. Press the releases at the top and bottom of the module and slide the module out of the chassis slot.

3. Cover all unused slots with the Card Slot Filler, Catalog Number

1746-N2.

5–2

Chapter 5

Installation and Wiring

Network Wiring

Using Extended

Node Capability

A 1/2 watt terminating resistor must be attached across line 1 and line 2 of the connectors at each end (scanner and last physical device) of the network.

The size of the resistor depends upon the baud rate and extended node capability, as shown below:

Baud Rate

All Baud Rates

57.6K baud

115.2K baud

230.4K baud

Terminating Resistor Size

82

W 1/2 Watt

150

W 1/2 Watt

150

W 1/2 Watt

82

W 1/2 Watt

Maximum Cable Distance

(Belden 9463)

10,000 feet at 57.6K baud

5,000 feet at 115.2K baud

2,500 feet at 230.4K baud

3048 meters (10,000 feet)

1524 meters (5,000 feet)

762 meters (2,500 feet)

Terminating

Resistor

RIO Scanner

Line 1 – Blue

Shield – Shield

Line 2 – Clear

DCM

FAULT

COMM

RIO Link

Connector

CONFIGURATION

RACK ADDR

RACK SIZE

1/4 1/2 3/4 1

FIRST I/O GROUP

0 2 4 6

DATA RATE (K B/S)

57.6 115.2 230.4

LINE 1 _______

SHIELD ______

LINE 2 _______

I/O

GROUP

(LSB)

RACK

ADDRESS

(MSB)

X

X

RACK

SIZE

LAST RACK

CLR ON FLT

DATA

RATE

1747-DCM

Direct Communication Module

Line 1 – Blue

Shield – Shield

Line 2 – Clear

1747–DCM

1747-DCM

Direct Communication Module

Line 1 – Blue

Shield – Shield

Line 2 – Clear

Terminating

Resistor

5–3

Overview

Chapter

6

Programming

This chapter shows you how to program ladder logic in the supervisory processor/scanner and the distributed SLC to transfer data via the DCM.

Topics include:

• overview

• programming examples

• status words

• applications using status word bits

Both the supervisory processor/scanner and the distributed SLC transfer data to and from the DCM automatically via their I/O and the RIO scan. The

DCM, as a common memory site for both supervisory and distributed processors, has two addresses; one for the supervisory processor/ scanner and one for the SLC. The supervisory processor/scanner address is the DCM logical rack address as set by DCM SW-1 switches 1 through 6.

The distributed SLC address is determined by the slot where the DCM is physically installed.

The supervisory processor/scanner and distributed SLC addresses can be different; however, the bit position part in each word must be the same.

In the programming examples on the following page, an Examine If Open contact similar to the one shown below is used in each output rung:

I:4.0

]/[

08

This instruction checks that the Logical OR bit of the status word is false.

Whenever any of the status word bits (except the User Status Flag bit) is set, it is indication that a condition has occurred in your logic program that may require inspection. If this happens you would normally want to inhibit some outputs by using a ladder logic instruction. Using an Examine If Open (XIO) instruction examining the Logical OR bit (word 0, bit 8 for SLC; word 0, bit

10 for PLC) is the easiest way of doing this.

6–1

Chapter 6

Programming

Programming Examples

The following programming examples are typical of applications using the

DCM. In each example the portion of the scanner image assigned to the

DCM is logical rack 2, starting group 0, 1 full rack, and is located in SLC physical slot 3.

6–2

PLC

SLC

Input

Physical Slot # 0 1 2 3 4 5 6

PLC

Processor

Physical Input into PLC – Physical Output from SLC

RIO

Scanner

RIO

DCM

SLC

Processor Output

IN

I:000

] [

00

O:021

( )

00

I:3.1

] [

00

I:3.0

]/[

08

Logical Or Status Bit

O:1.0

( )

00

OUT

In the example above, PLC output O:021/00 controls the (on/off) status of

DCM input I:3.1/00.

I:3.1/00 is used as a conditional ladder logic along with the Logical OR input status bit to control SLC output O:1.0/00.

Chapter 6

Programming

Input

SLC

Processor

Physical Input into SLC – Physical Output from PLC

DCM

RIO

RIO

Scanner

PLC

Processor

Output

ÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇ

SLC

IN ] [

( )

ÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇ 00

00

ÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇ

ÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇÇ

I:021

I:020

O:001

PLC ] [ ]/[

( ) OUT

00 10

00

Logical Or Status Bit

PLC

SLC

Input

PLC

Processor

Physical Input into Both PLC and SLC (Logical AND) – Physical Output from SLC

RIO

Scanner

RIO

DCM

SLC

Processor

Input

Output

IN

I:000

] [

00

IN

I:2.0

] [

00

O:021

( )

00

I:3.1

] [

00

I:3.0

]/[

08

Logical Or Status Bit

O:1.0

( )

00

OUT

6–3

Chapter 6

Programming

Input

First

SLC

Processor

Physical Input into First SLC – Physical Output from Second SLC

For this example the second SLC has a logical PLC rack address of 3 and an

SLC slot address of 4.

PLC with

RIO scanner

DCM

RIO

DCM

Second

SLC

Processor

Output

SLC

PLC

IN

I:2.0

] [

00

(No physical input into the PLC)

O:3.1

( )

00

I:4.1

] [

00

I:4.0

]/[

08

Logical Or Status Bit

O:1.0

( )

00

I:021

] [

00

I:020

]/[

10

Logical Or Status Bit

O:031

( )

00

OUT

When transmitting data from a PLC to an SLC, if the Clear On Fault (CLR

ON FLT) is active (switch is OFF), the instruction to examine the Logical

OR bit of the status word can be omitted as long as clearing the DCM input image table puts SLC outputs into a safe state for the specific application.

6–4

Chapter 6

Programming

Status Words

The first word of the DCM I/O image is the status word. The status word indicates the status of communication and data between the RIO scanner and the DCM. Depending on what logical rack size the DCM is configured for, it will transfer the following number of I/O words:

Rack Size

1/4 Logical Rack

1/2 Logical Rack

3/4 Logical Rack

Full Logical Rack

Number of RIO Words Transferred

One (plus one Status Word)

Three (plus one Status Word)

Five (plus one Status Word)

Seven (plus one Status Word)

Total Words

2

4

6

8

The figure below shows how I/O bits are transferred from the scanner to two

DCMs, each configured as a 1/2 logical rack device.

Bit Number: Decimal

Status Word:

Word 0

Word 1

Data Words:

Word 2

Word 3

Status Word:

Word 4

Word 5

Data Words:

Word 6

Word 7

15 14 13 12 11 10 9 8

ÍÍ ÍÍ ÍÍ Í

R

R

R

R R R

ÍÍ ÍÍ ÍÍ Í

7 6

R R

R

R

ÍÍ ÍÍ ÍÍ Í

R

R R R R R

ÍÍ ÍÍ ÍÍ Í

5 4

R R

3 2 1

R R R R

0

R R R R R R

DCM 1

1/2 Rack Device

DCM 2

1/2 Rack Device

R = Reserved for future use

RIO Scanner Input Status Word Examination (Decimal)

This is the input status word sent in a data transfer from a supervisory processor/RIO scanner to a DCM. These bits can be used as conditional logic in your SLC program to flag DCM, RIO, or supervisory processor system errors and/or status. Scanner status bits not defined below are reserved for future use.

DCM

ÉÉ ÉÉÉ ÉÉ ÉÉ É ÉÉ ÉÉ É ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÍÍ ÉÉ ÉÉ ÉÉ ÉÉ É ÉÉ ÉÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

ÉÉ ÉÉÉ ÉÉ ÉÉ É ÉÉ ÉÉ É ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÍÍ ÉÉ ÉÉ ÉÉ ÉÉ É ÉÉ ÉÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ

ÉÉ

Reserved Bits

ÉÉ

Status Bits

Logical OR of other Status Word bits. It is set when any other bit is set. It is cleared when all other bits are cleared.

Program/Test/Fault Mode bit. This bit is set whenever the supervisory processor is in the Program, Test, or Fault Mode.

DCM Initialization bit. This bit is set when the DCM is in its power-up initialization.

It will be cleared when valid data is received from the supervisory processor output image table.

Communication Error bit. This bit is set whenever the DCM detects an RIO communication error. It is cleared when the Communication error is cleared.

6–5

Chapter 6

Programming

DCM/SLC Output Status Word Examination (Octal)

This is the output image status word sent in a data transfer from a DCM to a supervisory processor/scanner. These bits can be used as conditional logic in your supervisory processor program to flag DCM or SLC system errors and/or status. DCM/SLC status bits not defined below are reserved for future use.

Both the decimal and octal bit addresses are shown below to assist you in programming your supervisory (PLC) processor and distributed SLC processor.

SLC 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

ÉÉ ÉÉÉ ÉÉ É ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ É ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ É É ÉÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉÉ

PLC

ÉÉ ÉÉ ÉÉÉ ÉÉ ÍÍ ÍÍ ÍÍ ÍÍ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ É ÉÉ ÉÉ É ÉÉ É ÉÉÉ ÉÉ

17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0

ÉÉ ÉÉ ÉÉÉ ÉÉ ÍÍ ÍÍ ÍÍ ÍÍ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ ÉÉ ÉÉÉ ÉÉ ÉÉ É ÉÉ ÉÉ É ÉÉ É ÉÉÉ ÉÉ

ÉÉ

Reserved Bits

ÉÉ

Status Bits

Logical OR of Status Word bits 11 and 12 (9 and 10 for

SLC). It is set when either 11 or 12 (9 or 10) is set. It is cleared when 11 or 12 (9 or 10) is cleared.

Program/Test/Fault Mode bit. This bit is set whenever the SLC controlling the DCM is in the Program, Test, or

Fault Mode.

DCM Output Data Invalid bit.

➀

This bit is set when DCM output image data could be invalid.

User Status Flag bit. This status bit is available for you to use in your application.

➀

Always use the DCM Output Data Invalid bit to determine the validity of SLC data sent from the DCM to the scanner. If you use the Program/Test/Fault Mode bit you may incorrectly receive an indication that the SLC data being sent from the DCM to the scanner is valid. This occurs because for a brief period after the

Program/Test/Fault mode bit is cleared the data sent from the DCM to the scanner will not be valid.

6–6

Chapter 6

Programming

Applications Using I/O Status

Word Bits

You can use the status bits in your ladder logic to monitor various conditions of the remote processor and the RIO network. Some examples for using the status word bits are given here. Each of the examples shows how ladder logic rungs could be programmed in the SLC processor to respond to the condition of a status bit from the RIO scanner.

Important: The application examples assume the portion of the scanner image assigned to the DCM is logical rack 2, starting group 0, 1 full rack, and is located in SLC physical slot 3.

RIO Scanner Status Word

Using the Program/Test/Fault Mode Bit

When the RIO scanner’s supervisory processor is in Program, Test, or Fault

Mode, its outputs are automatically inhibited (reset off) unless Hold Last

State is used. However, outputs sent to the DCM (DCM inputs) are not automatically inhibited. If you want to inhibit any one SLC output controlled by a DCM input, you can use an Examine If Open (XIO) instruction addressed to the Program/Test/Fault Mode bit (I:3.0/9 in the example below). This assumes an SLC output is being driven by an input

(I:3.1/0) from the scanner to the DCM, as shown below.

SLC Rung to Monitor

RIO Scanner Status Bit 09

DCM Conditional Program/Test/Fault SLC

I:3.1

] [

00

Input

I:3.0

]/[

09

Status Bit

O:1.0

( )

00

Output

If you want to clear the DCM’s entire input image (data from the RIO scanner when the RIO scanner’s supervisory processor is in Program/Test/

Fault Mode), you can set the DCM Clear On Fault DIP switch to the OFF

position. Please refer to chapter 4, Module Configuration, for more

information on this DIP switch.

DCM/SLC Output Status Word

Using the Data Invalid Bit

Whenever the distributed SLC leaves Program/Test/Fault Mode and enters

Run Mode, there is a time period after the Program/Test/Fault Mode bit is cleared when the data sent from the DCM/SLC to the RIO scanner is invalid.

For this reason, the Program/Test/Fault Mode bit should not be used by the

RIO scanner’s supervisory processor to determine the validity of data sent from the DCM. Instead, both processors’ programs should use the DCM output Data Invalid bit (12 octal).

6–7

6–8

Chapter 6

Programming

To ensure that the DCM output Data Invalid bit is cleared (signifying to the

RIO scanner’s supervisory processor that data is valid), the SLC ladder logic rung shown below must be included as the last rung in your SLC ladder logic program.

SLC Rung addresses bit 10 (decimal);

RIO Scanner ’s supervisory processor receives bit 12 (octal).

O:3.0

(U)

10

The RIO scanner’s supervisory processor ladder logic program should use the DCM output Data Invalid bit to condition any supervisory processor outputs whose state is dependent upon valid data from the DCM/distributed

SLC. An example of a PLC-5 processor rung that requires this conditioning is shown below.

PLC-5 Rung

SLC addresses bit 10 (decimal);

PLC receives bit 12 (octal).

I:021

] [

00

I:020

]/[

12

O:000

( )

00

This rung uses data from the DCM (word 1, bit 0 PLC address I:021/00) to energize a PLC-5 output: bit 0, of rack 0, module group 0. It is conditioned with the Data Invalid bit. By using the DCM output Data Invalid bit in this example, the PLC-5 will not energize the output shown above unless the data received from the SLC/DCM is valid.

Using the User Status Flag Bit

This status bit (13) is available for your particular application. It is cleared on powerup and thereafter is never operated on by the DCM. After powerup this bit is only set (1) or cleared (0) by your SLC ladder logic program.

A typical application using this bit would be to inform the RIO scanner’s supervisory processor that the SLC is disabling the slot where the DCM is located. If the DCM slot is disabled while the SLC is in the Run Mode, data sent to the RIO scanner will be last state data (invalid). Without using the

User Status Flag bit, no indication that data is not being updated would be sent to the RIO scanner (that is, neither the Program/Test/Fault Mode bit nor the Invalid Data bit would be set). If your SLC ladder logic program sets the

User Status Flag bit prior to disabling the DCM slot, the supervisory processor can use this bit in its ladder logic where appropriate.

!

ATTENTION: Make certain that you have thoroughly examined the effects of disabling the DCM slot before doing so in your application.

An example of how rungs might be programmed in the two processors to indicate disabling of the DCM slot is shown on the next page.

Chapter 6

Programming

SLC Rungs

Set User Status Flag Bit

Condition(s)

➀

Disable DCM

Enable DCM

Clear User Status Flag Bit

➀

Condition(s)

Condition(s)

➁

Condition(s)

➁

User Status Flag Bit

O:13.0

(L)

11

➂

IOM

IMMEDIATE OUT w MASK

Slot 0:3.0

Mask 0800

S2:11

(U)

➃

03

S2:11

➃

(L)

03

O:3.0

(U)

11

➂

➀

Condition(s) to set User Status Flag bit is the same condition(s) to disable the DCM slot. When setting the

User Status Flag bit, an Immediate I/O (IOM) instruction must be used.

➁

Condition(s) to clear User Status Flag bit is the same condition(s) to enable the DCM slot.

➂

The SLC addresses this bit as bit 11 (decimal); the PLC-5 receives this bit as bit 13 (octal).

➃

S2:11-S2:12 – These two words are bit mapped to represent the 30 possible I/O slots in an SLC system.

S2:11/0 represents I/O slot 0 up through S2:12/14 which represents slot 30. S2:12/15 is unused.

After programming the SLC to set and clear the User Status Flag bit, this bit can be used to condition any PLC-5 output in this example whose state is dependent upon the data from the distributed SLC being valid.

PLC-5 Rung

I:021

] [

00

I:020

]/[

13

O:000

( )

00

The PLC-5 rung uses data from the DCM (word 1, bit 0) to energize PLC-5 output 0. It is conditioned on the User Status Flag bit being cleared. If the

SLC is programmed to set the User Status Flag bit prior to disabling the

DCM slot, the PLC-5 will never energize output 0 when data from the SLC is invalid. For more information on how to enter PLC ladder logic, see your

PLC-5 programming manual.

6–9

Chapter 6

Programming

RIO Scanner Input Status and DCM/SLC Output Status

Using the Logical OR Bit

Whenever any of the status word bits (except the User Status Flag bit) are set, the Logical OR bit is set. Using an Examine If Open (XIO) instruction examining the Logical OR bit (word 0, bit 8 for SLC; word 0, bit 10 for

PLC-5) in your ladder logic, you could inhibit any outputs or processors when this bit is set.

SLC Rung to Monitor

PLC-5 Status Bit 08

I:3.1

] [

00

I:3.0

]/[

08

O:1.0

( )

00

6–10

DCM Status Indicators

Chapter

7

Troubleshooting

This chapter shows you how to identify and correct errors that you may encounter using LEDs. The topics include:

•

DCM status indicators

• troubleshooting using the FAULT LED (red)

• troubleshooting using the COMM LED (green)

Two LEDs indicate the status of the DCM.

DCM

FAULT

COMM

Red

Green

Troubleshooting Using the

FAULT LED (Red)

If LED is:

On

Blinking

Cause:

Internal Fault

Configuration Error

Corrective action:

Cycle power to the I/O chassis containing the DCM.

Replace DCM if red LED remains lit after powerup.

Check that the DIP switch settings are correct. Make sure that I/O group and rack size settings are compatible.

➀

Also see that the setting for rack address is correct. Refer

to chapter 4, Module Configuration, for help with DIP

switches.

No action required.

Off

Normal State

➀

The DCM cannot cross logical rack boundaries. Therefore, as an example, configuring the module for 1/2 logical rack with starting group 6 will cause a configuration error.

7–1

Chapter 7

Troubleshooting

Troubleshooting Using the

COMM LED (Green)

If LED is:

On

Blinking

Off

Cause:

Normal State

RIO scanner’s processor in Program/Test Fault

Mode

RIO scanner’s processor not connected to scanner

RIO scanner’s processor rack inhibited between RIO scanner’s

No action required.

Corrective action:

Check for RIO scanner’s processor error, correct condition, and cycle power to DCM.

Check that the scanner is properly installed in rack (RIO scanner’s processor–2, #3).

Check RIO scanner’s processor rack integrity, correct any problem, and cycle power to DCM.

Check that the baud rate of the DCM matches the baud rate of the scanner.

Check cable connections from the RIO scanner’s processor or scanner to the DCM.

Check that the DCM connector is properly installed.

7–2

Chapter

8

Application Examples

This chapter provides and examines two applications of the DCM.

• basic example

• supplementary example

Basic Example

Rack 1

Input Switch

In the following application, the 1747-DCM in the remote rack 2 will monitor the 1747-SN data from the local rack 1. The program examples in both local and remote rack CPUs consist of 1 rung each. When input I:1/0 is enabled in the local rack, the output O:3.1/0 condition is transferred to the

1747-DCM input image via the 1747-SN output image. This condition enables O:2/0 in the remote rack output card.

Rack 2

ÉÉ

É É ÉÉ

É É ÉÉ

É É ÉÉ

É É ÉÉ

É É ÉÉ

É É ÉÉ

ÉÉ

= slot not used

ÉÉ

RIO

(Belden 9463)

1747-SN Module Configuration

➀

Baud Rate =

G-file Size =

57.6K baud

3 words

G-File

Word 0

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Reserved

Word 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

= Starting Address 0

Word 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

= 1/4 Rack Size

➀

See SN manual for further details on configuration.

8–1

Chapter 8

Application Examples

DCM configuration:

Rack Address = 1

I/O Group =

Baud Rate =

0

57.6K baud

Clear On Fault = no

Last Rack =

Rack Size = no

1/4

DIP Switch Settings

Switch 1

1 2 3 4 5 6

ON X X X X X

OFF X

Switch 2

7 8 1 2 3 4 5 6

X X X X X X X X

7 8

= Not used

System Configuration for Rack 1

Amount

1

1

1

1

1

1

Device

Power Supply

SLC 5/02 Processor

4-Slot Rack

AC Input, 16 Inputs

Relay Output, 16 Outputs

Scanner

Catalog Number

1746-P2

1747-L524

1746-A4

1746-IA16

1746-OW16

1747-SN

System Configuration for Rack 2

Amount

1

1

1

1

1

Device

Power Supply

SLC 5/01 Processor

4-Slot Rack

Relay Output, 16 Outputs

DCM

Catalog Number

1746-P2

1747-L511

1746-A4

1746-OW16

1747-DCM

8–2

Chapter 8

Application Examples

Image Table Configuration

Output Image

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

SN

O:3.1/0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

Input Image

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

DCM

I:1.1/0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

Program Listing

When I:1/0 is set, enabling O:3.1/0 in the SN output image, the data is sent to the input image of the DCM I:1.1/0. The output in rack 2 is then set to output module O:2/0.

Rack 1, Program 1

I:1

] [

0

From Input Switch

O:3.1

( )

0

To SN Output

Word 1, Bit 0

Rack 2, Program 2

I:1.1

] [

0

From DCM Input

Word 1, Bit 0

O:2

( )

0

8–3

Chapter 8

Application Examples

Supplementary Example

In the following application, the PLC-5/15, via its integrated RIO scanner and the DCM, will monitor the analog data from an SLC 500. This case is unique in that the data to be monitored is twice what the DCM can transfer.

The program in the SLC 500 will multiplex the data into four, 4-word packets with a start and end of data word attached. The start and end of data word is also used to designate which module the data is coming from. This is also used by the PLC-5/15 to indicate that the data was transferred successfully.

RIO

(Belden 9463)

Module Configuration

PLC-5 configuration for scanner I/O status, inhibit bits:

S:27/0 =

*

S:27/1 =

S:27/2 =

S:27/3 =

* = Don’t care

0

1

1

DCM configuration:

Rack Address = 1

I/O Group = 0

Baud Rate = 57.6K baud

Clear on Faults = No

Last Rack =

Rack Size =

No

Full Rack

É

É

É

É

É

É

É

ÉÉ

= slot not used

ÉÉ

8–4

Chapter 8

Application Examples

DIP Switch Settings

ON

OFF

1 2 3

Switch 1

4 5

X X X X X

6

X

7 8 1 2 3

Switch 2

4

X X X X X X

5 6

X X

7 8

= Not used

System Configuration

Amount

1

1

1

2

2

1

Device

Power Supply

SLC 5/01 Processor

7-Slot Rack

Analog Input, 4 point

Analog Output, 4 point

DCM

Catalog Number

1746-P2

1747-L511

1746-A7

1746-NI4

1746-NO4I

1747-DCM

Image Table Configuration

DCM

O:1.7

O:4.0

O:4.1

O:4.2

O:4.3

O:5.0

O:5.1

O:5.2

O:5.3

O:1.0

O:1.1

O:1.2

O:1.3

O:1.4

O:1.5

O:1.6

Output Image

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Status Word to PLC-5 from SLC

Counter ACC word denotes module being read

Word 0 of analog module being read

Word 1 of analog module being read

Word 2 of analog module being read

Word 3 of analog module being read

Counter ACC word denotes module being read

Not used

NO4I word 0

NO4I word 1

NO4I word 2

NO4I word 3

NO4I word 0

NO4I word 1

NO4I word 2

NO4I word 3

8–5

Chapter 8

Application Examples

DCM

NI4

NI4

I:1.0

I:1.1

I:1.2

I:1.3

I:1.4

I:1.5

I:1.6

I:1.7

I:2.0

I:2.1

I:2.2

I:2.3

I:3.0

I:3.1

I:3.2

I:3.3

Input Image

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Status Word to SLC from PLC-5

Not used

Not used

Not used

Not used

Not used

Not used

Not used

NI4 word 0

NI4 word 1

NI4 word 2

NI4 word 3

NI4 word 0

NI4 word 1

NI4 word 2

NI4 word 3

Program Listing for 5/01

Processor File: MULTPLX1.ACH

Rung 0 sets the starting point of the C5:0 counter. This is done on the first scan of the program S:1/15

(first scan bit) and C5:0/DN (done bit 0) of the counter, ensuring that only the analog modules in slots 2 through 5 are read.

RUNG

2.0

C5:0

] [

DN

MOV

MOVE

Source

Dest

2

C5:0.ACC

S:1

] [

15

Rung 1 increments the C5:0 every 5.12 seconds. The value in the ACC is referenced to the slot that the

DCM will send the data from, starting at slot 2.

RUNG

2.1

S:4

] [

8

5.12 Seconds Time Bit

CTU

Countup

Counter

Preset

Accum

C5:0

6

0

8–6

Chapter 8

Application Examples

For rungs 2.2 through 2.5 the module number being monitored is shown above each example. For each rung, when SOURCE A = C5:0.ACC equals the value in SOURCE B = MODULE #, the rung moves the module number to word 1 of the DCM output file. This verifies the start of the data and the module number it’s coming from. Then it copies the four words of analog data to the DCM output words 2 through 5, followed by the module number at word 6 to indicate the end of data.

Module Number Monitored = 2

RUNG

2.2

EQU

EQUAL

Source A C5:0.ACC

Source B

0

2

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.1

0

COP

COPY FILE

Source

Dest

Length

#I:2.0

#0:1.2

4

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.6

0

RUNG

2.3

Module Number Monitored = 3

EQU

EQUAL

Source A C5:0.ACC

0

Source B 3

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.1

0

COP

COPY FILE

Source

Dest

Length

#I:3.0

#0:1.2

4

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.6

0

8–7

Chapter 8

Application Examples

RUNG

2.4

Module Number Monitored = 4

EQU

EQUAL

Source A C5:0.ACC

0

Source B 4

RUNG

2.5

Module Number Monitored = 5

EQU

EQUAL

Source A C5:0.ACC

Source B

0

5

<END>

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.1

0

COP

COPY FILE

Source

Dest

Length

#I:4.0

#0:1.2

4

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.6

0

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.1

0

COP

COPY FILE

Source

Dest

Length

#I:5.0

#0:1.2

4

MOV

MOVE

Source

Dest

C5:0.ACC

0

0:1.6

0

8–8

Chapter 8

Application Examples

RUNG

2.0

Module Number Monitored = 2

Program Listing for PLC5/15

The following examples are for rungs 2.0 through 2.3. The module number being monitored is shown above the examples. For each rung, the first EQU monitors the module number and the start of the data transfer, while the second EQU monitors the module number and the end of the data transfer.

The COP then moves the four words of analog data to an integer file.

EQU

EQUAL

Source A

Source B

I:011

0

2

EQU

EQUAL

Source A

Source B

I:016

0

2

COP

COPY FILE

Source

Dest

Length

#I:012

#N7:0

4

RUNG

2.1

Module Number Monitored = 3

EQU

EQUAL

Source A

Source B

I:011

0

3

EQU

EQUAL

Source A

Source B

I:016

0

3

RUNG

2.2

Module Number Monitored = 4

EQU

EQUAL

Source A

Source B

I:011

0

4

EQU

EQUAL

Source A

Source B

I:016

0

4

COP

COPY FILE

Source

Dest

Length

#I:012

#N7:4

4

COP

COPY FILE

Source

Dest

Length

#I:012

#N7:8

4

RUNG

2.3

Module Number Monitored = 5

EQU

EQUAL

Source A

Source B

I:011

0

5

EQU

EQUAL

Source A

Source B

I:016

0

5

COP

COPY FILE

Source

Dest

Length

#I:012

#N7:12

4

<END>

8–9

Appendix

A

Specifications

This appendix provides the following module and system specifications.

• electrical specifications

• environmental specifications

• network specifications

It also discusses throughput time for the DCM.

Electrical Specifications

Backplane Current Consumption

Environmental Specifications

Operating Temperature

Storage Temperature

Humidity Rating

Agency Certification

(when product or packaging is marked)

360mA at 5V

0

°

C to 60

°

C (32

°

F to 140

°

F)

−

40

°

C to

+

85

°

C (

−

40

°

F to

+

185

°

F)

5% to 95% noncondensing

•

CSA certified

•

CSA Class I, Division 2

Groups A, B, C, D certified

•

UL listed

•

CE marked for all applicable directives

Network Specifications

Us n xten e

Baud Rate

57.6K baud

115.2K baud

230.4K baud

57.6K baud

115.2K baud

230.4K baud

Maximum Cable Distance

(Belden 9463)

10,000 feet at 57.6K baud

5,000 feet at 115.2K baud

2,500 feet at 230.4K baud

3048 meters (10,000 feet)

1524 meters (5,000 feet)

762 meters (2,500 feet)

82

W 1/2 Watt

1

82

Resistor Size

W 1

W 1/2 Watt

A–1

Appendix A

Specifications

Throughput Timing

Use the following steps to determine the maximum throughput time in your application.

1. Determine and record the PLC and SLC delay by following these instructions:

PLC

SLC

I/O circuit delay:

I/O scan time:

Program scan time:

+

+

+

+

PLC Delay:

=

SLC Delay:

=

2. Record the remote I/O delay:

Remote I/O delay:

3. Record the DCM delay. This should be <10 msec.:

DCM delay:

4. Using your recorded values above, determine the maximum throughput time for your application as shown below:

PLC Delay:

Remote I/O delay:

+

DCM delay:

+

SLC Delay:

+

Maximum throughput time:

=

A–2

Directions

Addressing Review

Appendix

B

DCM Addressing Worksheet

This appendix provides a worksheet for keeping track of the elements of each

I/O address for your system’s DCMs. Topics include:

• directions

• addressing review

In the table on the next page, enter the elements of each I/O address for each

DCM in your system. All DCM inputs and outputs are addressed with respect to the SLC.

Make sufficient copies of this worksheet to cover all DCMs in your system.

PLC Addresses

PLC Input Address

I:023/10

I = Input

02 = Logical Rack

3 = I/O Group

10 = Bit (octal)

PLC Output Address

O:017/10

O = Output

01 = Logical Rack

7 = I/O Group

10 = Bit (octal)

SLC Addresses

SLC Input Address

I:2.3/8

I = Input

2 = Physical Slot

3 = Word

8 = Bit (decimal)

SLC Output Address

O = Output

1 = Physical Slot

7 = Word

8 = Bit (decimal)

If you configure the DCM as:

1/4 Rack

1/2 Rack

3/4 Rack

Full Rack

Then:

1 data word (16 bits of I/O data) is transferred.

3 data words (48 bits of I/O data) are transferred.

5 data words (80 bits of I/O data) are transferred.

7 data words (112 bits of I/O data) are transferred.

O:1.7/8

Including the Status Word

Total transfer = 2 words

Total transfer = 4 words

Total transfer = 6 words

Total transfer = 8 words

B–1

Appendix B

DCM Addressing Worksheet

1/4

Logical

Rack

1/2

Logical

Rack

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

PLC Output

O:

O:

O:

O:

O:

O:

Rack #

DCM Input Image Table

I/O Group Bit (octal) SLC Input

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

Slot # Word Bit (decimal)

Continued on next page.

B–2

Appendix B

DCM Addressing Worksheet

3/4

Logical

Rack

Full

Logical

Rack

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

PLC Output

O:

O:

O:

O:

O:

O:

Rack #

DCM Input Image Table (continued)

I/O Group Bit (octal) SLC Input Slot #

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

Word Bit (decimal)

B–3

Appendix B

DCM Addressing Worksheet

1/4

Logical

Rack

1/2

Logical

Rack

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

PLC Input

I:

I:

I:

I:

I:

I:

Rack #

DCM Output Image Table

I/O Group Bit (octal) SLC Output

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

Slot # Word Bit (decimal)

Continued on next page.

B–4

Appendix B

DCM Addressing Worksheet

3/4

Logical

Rack

Full

Logical

Rack

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

I:

PLC Input

I:

I:

I:

I:

I:

I:

Rack #

DCM Output Image Table (continued)

I/O Group Bit (octal) SLC Output Slot #

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

O:

Word Bit (decimal)

B–5

Index

Direct Communication Module

User Manual

Numbers

1/2 rack, 2–3, 4–6

1/4 rack, 2–3, 4–6

3/4 rack, 2–3, 4–6

A

adapter, 1–4 extended node capability, 1–4

interaction with scanners, 1–2 on RIO link as slave device, 1–2

adapter image, 1–4

addressing ladder logic instructions, 3–1

PLC addresses, 3–2

SLC addresses, 3–3

addressing worksheet directions, B–1

Allen-Bradley, P–4 contacting for assistance, P–4

application examples

basic DCM, 8–1

programming, 6–2

supplementary DCM, 8–4

using status word bits, 6–7 applications using status word bits, 6–7

Data Invalid bit in the SLC Status Word,

6–7

Logical OR bit, 6–10

Program/Test/Fault Mode bit in the RIO

scanner status word, 6–7

User Status Flag bit in the SLC Status

Word, 6–8

available scanners, 2–2

B

backplane current consumption, A–1

basic DCM application example, 8–1

baud rate

resistor, 2–4 specifications, 2–4, 5–3, A–1

Belden 9463 cable, maximum distance, 2–4,

5–3, A–1

bit address, 3–2, 3–3

CE certification, 5–1

chassis slot

card guides, 5–2

Card Slot Filler, 5–2

Clear On Fault (SW2-3), 4–7

COMM LED, 1–1

Communication Error bit, 6–5

configuring the module, 4–1

contacting Allen-Bradley for assistance, P–4

contents of manual, P–2

D

Data Invalid bit, 6–7

Data Rate (SW2-1 and SW2-2), 4–7

DCM features, 1–1 hardware, 1–1 cable tie slots, 1–1

COMM LED, 1–1

DIP switches, 1–1

FAULT LED, 1–1 front, side and door labels, 1–1 self-locking tabs, 1–1

DCM Initialization bit, 6–5

DCM installation and wiring, 5–1

DCM Output Data Invalid bit, 6–6

DCM overview, 1–1

DCM status word bit examination (decimal)

DCM output data invalid bit, 6–6

User Status Flag, 6–6

definitions, P–3

determining maximum throughput time, A–2

DIP switches, 1–1, 4–1

switch 1 settings, 4–2

I/O Group (SW1-7 and SW1-8), 4–2

Rack Addresses (SW1-1 through

SW1-6), 4–3

switch 2 settings, 4–6

Clear On Fault (SW2-3), 4–7

Data Rate (SW2-1 and SW2-2), 4–7

Last Rack (SW2-4), 4–6

Module Rack Size (SW2-5 and SW2-6),

4–6

door label, 1–1

C

cable distance, maximum, 2–4, 5–3, A–1

cable tie slots, 1–1, 5–2

I–1

I–2

Index

Direct Communication Module

User Manual

E

electrical specifications, A–1

EMC Directive, 5–1

environmental specifications, A–1

equipment needed, 2–1

errors, troubleshooting, 7–2

European Union Directives Compliance, 5–1

Examine If Open instruction (XIO), 6–7, 6–10

examples

basic DCM application, 8–1

programming, 6–2

status word bit application, 6–7

supplementary DCM application, 8–4

extended node capability, 1–4 of scanners and adapters, 1–4 of the DCM, 1–4

specifications, 2–4, 5–3, A–1

F

FAULT LED, 1–1

flashing LED, 7–2

front label, 1–1

full rack, 2–3, 4–6

I

I/O Group (SW1-7 and SW1-8), 4–2

I/O group address, 3–2

I/O image tables, 3–4

image division configuration, scanner, 1–5

image mapping, 3–5

inserting the cable tie, 5–2

installation, getting started, 2–1

installing the module, 5–1

L

labels, front, side and door, 1–1

ladder logic instructions, addressing, 3–1

Last Rack (SW2-4), 4–6

LEDs, 7–1 blinking, 7–1

COMM (green), 7–2

FAULT (red), 7–1 steady state, 7–1 troubleshooting using, 7–1

link wiring, 5–2

logical group, 1–4

Logical OR bit, 6–5, 6–6, 6–10

logical rack, 1–4

logical specifications, 1–2

G

getting started, 2–1

procedure, 2–2

glossary terms, P–3

green LED, troubleshooting using, 7–2

M

manuals, related, P–2

Module Rack Size (SW2-5 and SW2-6), 4–6

module release, 5–2

H

hardware features, 1–1 cable tie slots, 1–1

COMM LED, 1–1

DIP switches, 1–1

FAULT LED, 1–1 front, side and door labels, 1–1

RIO link connector, 1–1 self-locking tabs, 1–1 hardware overview, 1–1 hardware features, 1–1

Hold Last State, in status word applications,

6–7

humidity rating, A–1

N

network specifications, A–1

network wiring, 5–3

P

physical specifications, 1–2

PLC addresses, 3–2 bit address, 3–2

I/O group address, 3–2 rack address, 3–2

Index

Direct Communication Module

User Manual

PLC scanner output image, 3–5, 3–6

power up, system, 2–4

Program/Test/Fault Mode bit, 6–5, 6–6, 6–7

programming examples, 6–2

physical input into both PLC and SLC –

physical output from SLC, 6–3

physical input into first SLC – physical

output from second SLC, 6–4

physical input into PLC – physical output

from SLC, 6–2

physical input into SLC – physical output

from PLC, 6–3

programming overview, 6–1

publications, related, P–2

R

rack address, 3–2

Rack Address (SW1-1 through SW1-6), 4–3

rack size

1/2 rack, 2–3, 4–6

1/4 rack, 2–3, 4–6

3/4 rack, 2–3, 4–6 full rack, 2–3, 4–6

number of data words transferred

according to, 2–3

recording I/O addresses, B–1

red LED, troubleshooting using, 7–1

remote I/O

adapter, 1–2 communications link, 1–2

link connector, 1–1

removing the module, 5–2

required tools and equipment, 2–1

resistor baud rate, 2–4

RIO adapter, 1–2

RIO communications link, 1–2

RIO link connector, 1–1

RIO scanner status word bit examination

(decimal), 6–5

Communications Error bit, 6–5

DCM initialization bit, 6–5

Logical OR of other status word bits, 6–5

Program/Test/Fault Mode bit, 6–5

RIO scanners, 2–2

S

scanner, image division, 1–4 logical groups, 1–4 logical racks, 1–4 scanner image division, 1–4

configuration example, 1–5

scanners number of physical and logical devices

supported by, 2–3

selection, 2–2

self-locking tabs, 1–1

setting the DIP switches, 4–1

side label, 1–1

SLC addresses, 3–3 bit address, 3–3 slot address, 3–3 word address, 3–3

SLC input image, 3–5, 3–6

slot address, 3–3

specifications, A–1

cable distance, 2–4, 5–3, A–1

electrical, A–1 environmental, A–1 network, A–1

resistor size, 2–4, 5–3, A–1

temperature and humidity, A–1

start-up instructions, 2–1

status words, 1–6, 6–5 about the, 1–6

DCM status word bit examination (octal),

6–6

RIO scanner status word bit examination

(decimal), 6–5

supplementary DCM application example,

8–4

SW1-1 through SW1-6, DIP switch, Rack

Address, 4–3

SW1-7 and SW1-8, DIP switch, I/O Group,

4–2

SW2-1 and SW2-2, DIP switch, Data Rate,

4–7

SW2-3, DIP switch, Clear On Fault, 4–7

SW2-4, DIP switch, Last Rack, 4–6

I–3

I–4

Index

Direct Communication Module

User Manual

SW2-5 and SW2-6, DIP switch, Module Rack

Size, 4–6

system overview, 1–2

data exchange between a PLC and SLC,

1–2 logical rack, 1–2 remote I/O analysis, 1–2

system configuration restriction factors,

1–2

system powerup, 2–4

throughput timing, A–2

tools needed, 2–1

troubleshooting, 7–1

contacting Allen-Bradley, P–4

using the COMM LED (green), 7–2

using the FAULT LED (red), 7–1

U

User Status Flag bit, 6–6, 6–8

T

temperature specifications, A–1 operating, A–1 storage, A–1

terminating resistor, size of, 5–3

terms, P–3

W

wiring the network, 5–3

word address, 3–3

worksheets, B–1

Allen-Bradley, a Rockwell Automation Business, has been helping its customers improve productivity and quality for more than 90 years. We design, manufacture and support a broad range of automation products worldwide. They include logic processors, power and motion control devices, operator interfaces, sensors and a variety of software. Rockwell is one of the world’s leading technology companies.

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Allen-Bradley Headquarters, 1201 South Second Street, Milwaukee, WI 53204 USA, Tel: (1) 414 382-2000 Fax: (1) 414 382-4444

Publication 1747-6.8 – June 1996

Supersedes Publication 1747-NM007 – September 1993

40072-032-01(A)