Rockwell Automation 1747-DCM, D17476.8 User Manual

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Allen-Bradley

Direct Communication

User

Module

(Cat. No. 1747-DCM)

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.

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.

New Information

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 See

Related documentation updated preface Quick Start for Experienced Users chapter 2 Default DIP switch settings chapter 4 CE certification chapter 5, appendix A DCM clear on fault DIP switch chapter 6

able of Contents

Direct Communication Module User Manual

Preface

Who

Should Use this Manual

Purpose

Terms Common Allen-Bradley

of this Manual Contents Related

Local

Technical Product Assistance P–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your Questions or Comments on this Manual P–5. . . . . . . . . . . . . . . . . . . . .

of this Manual

Documentation

and Abbreviations

Techniques Used in this Manual

Support

Product Support

P–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P–5. . . . . . . . . . . . . . . . . . . . . . . . . .

P–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Overview

Quick Start for Experienced Users

Addressing

Chapter 1

Hardware Overview 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Overview 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

What

Is a Remote I/O Adapter?

Extended

Scanner Image Division 1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scanner

Data Exchange Between RIO Scanners and the DCM 1–6. . . . . . . . . . . . . . . . .

What

Node Capability

Image Division Configuration Example

Is the Status W

ord? 1–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter 2

Required Tools and Equipment

Procedures 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter 3

Addressing

PLC/Scanner Addresses 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SLC Addresses 3–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

I/O

Image

Ladder Logic Instructions

Image T

PLC to DCM/SLC 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DCM/SLC

Mapping

ables 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

to PLC

1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1–5. . . . . . . . . . . . . . . . . . .

2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Module Configuration

Chapter 4

DIP Switches 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DIP

Switch 1 Settings Starting Rack

DIP

Rack

Last Rack (SW2-4) 4–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Clear Data

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

Address (SW1-1 through SW1-6)

Switch 2 Settings

Size (SW2-5 and SW2-6))

On Fault (SW2-3)

Rate (SW2-1 and SW2-2)

4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4–2. . . . . . . . . . . . . . . . . . .

4–3. . . . . . . . . . . . . . . . . . . . . . . . .

4–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

able of Contents

Direct Communication Module User Manual

Installation and Wiring

Programming

Chapter 5

Compliance

EMC Directive 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DCM

Installation 5–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Removal 5–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Network

to European Union Directives

Installation

Wiring

Chapter 6

Overview 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming Examples 6–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Physical Physical Physical

Physical

Status Words 6–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RIO DCM/SLC

Applications Using I/O Status W

RIO

DCM/SLC

RIO

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

Physical Output from SLC 6–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input into First SLC – Physical Output from Second SLC

Scanner Input Status W

Output Status W

Scanner Status W

Using

the Program/T

Output Status W

Using

the Data Invalid Bit

Using

the User Status Flag Bit

Scanner Input Status and DCM/SLC Output Status

Using

the Logical OR Bit

ord Examination (Decimal) 6–5. . . . . . . . . . . . .

ord Examination (Octal) 6–6. . . . . . . . . . . . . . . .

ord Bits

ord 6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

est/Fault Mode Bit

ord 6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5–1. . . . . . . . . . . . . . . . . . . . . . . . . .

5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–2. . . . . . . . . . . . . . . .

6–3. . . . . . . . . . . . . . . .

6–4. . . . . .

6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–7. . . . . . . . . . . . . . . . . . . . . . .

6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6–10. . . . . . . . . . . . .

6–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting

Application Examples

Chapter 7

DCM

Status Indicators Troubleshooting

Troubleshooting Using the COMM LED (Green) 7–2. . . . . . . . . . . . . . . . . . . . . .

Using the F

AULT LED (Red) 7–1. . . . . . . . . . . . . . . . . . . . . . . .

Chapter 8

Basic Example 8–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1747-SN DIP System System Image Program

Supplementary Example 8–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Module DIP System Image

Module Configuration

Switch Settings

Configuration for Rack 1 Configuration for Rack 2

able Configuration

Listing

Configuration

Switch Settings

Configuration

able Configuration

7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

able of Contents

Direct Communication Module User Manual

Specifications

DCM Addressing Worksheet

Program Program

Listing for 5/01 Listing for PLC5/15

Appendix A

Electrical Environmental Network Throughput

Specifications

iming A–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Appendix B

Directions B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Addressing Review B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PLC Addresses B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SLC Addresses B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

iii

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

Who Should Use this Manual

Purpose of this Manual

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 500t 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 Title Content

Describes the purpose, background, and scope of

Preface

1 Overview

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 Addressing Explains slot numbering and image mapping.

4 Module Configuration Provides DIP switch setting information. 5 Installation and Wiring

6 Programming

7 Troubleshooting Describes troubleshooting using front panel LEDs. 8 Application Examples

Appendix A Specifications

Appendix B DCM Addressing Worksheet

Quick Start

for Experienced Users

Serves as a Quick Start Guide for using the DCM.

Provides installation procedures and a wiring

diagram.

Shows how to program ladder logic in the PLCr

and the SLC 500, including an examination of

special programming instructions that affect system

response. Also examines the status word and its

applications.

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

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 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.

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

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.

Common Techniques Used in this Manual

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.

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

are Overvie

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

Hardw

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 _______

SW1

SW2

1747–DCM

I/O

GROUP

(LSB)

RACK

ADDRESS

2345678

(MSB)

X X

RACK

SIZE

LAST

RACK

CLR ON FL

2345678

DATA RATE

2345678 1

SW1 SW2

SERIAL NO.

SW 1

I/O

GROUP

(LSB)

RACK ADDR

(MSB)

SW 2

RACK SIZE

LAST

CLR ON FL

MADE IN USA

DATA RATE

CAT

MODULE

X X

RACK

DIRECT COMMUNICATION

SLC 500

8 7 6 5 4 3 2 1

Self–Locking Tab

Hardware Features

Hardware

Function

FAULT LED Displays operating status COMM LED Displays communication status Front, Side and Door Labels Provide module configuration information RIO Link Connector Provides physical connection to RIO network Cable Tie Slots Secure and route wiring from module DIP Switches Establish configuration parameters for the module Self–Locking Tabs Secure module in chassis slot

1–1

Chapter 1

stem Overvie

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

RIO

Scanner

PanelViewt

(adapter)

Distributed SLCs with DCMs (adapters)

RIO Communication Link

DCM 1

DCM 2

DCM 3

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

Compatible

Number

1785-LT/x PLC-5/15 Yes In adapter mode 1785-LT2 PLC-5/25 Yes In adapter mode 1785-LT3 PLC-5/12 Yes In adapter mode 1785-L30x PLC-5/30 Yes In adapter mode 1785-L40x PLC-5/40 Yes In adapter mode 1785-L60x PLC-5/60 Yes In adapter mode 1771-ASC Remote I/O Adapter Module No

1771-ASB Remote I/O Adapter Module

1771-AM1

1771-AM2

1784-F30D 1771-RIO Remote I/O Interface Module No

Catalog

Adapters

Device

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

Extended

Node

Capability

Series B and

C only

Yes

Comments

Series A, B, and C

1771-JAB Single Point I/O Adapter Module Yes 1771-DCM Direct Communication Module No 1778-ASB Remote I/O Adapter Module Yes 1747-ASB Remote I/O Adapter Module Yes

2706-xxxx 2705-xxx

2711-xx PanelView Terminal Yes 1336-RIO

1395-NA

1747-ASB

DL40 Datalinert RediPANELt

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 Yes

Yes

Must be catalog number 2706-ExxxxxB1.

1–3

Chapter 1

canner Image

Overview

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.

Divisi

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

Remote I/O

(Scanner

Image)

Processor I/O Image Scanner I/O Image Adapter

Logical Rack 1

Logical

Rack 2

Logical Rack 3

Logical Group 0

Logical

Group 7

Image

1–4

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.

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

Logical

Rack

Logical

Rack 2

Decimal Bit Number

Octal 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

Word 0

Word 1

Word 2

Word 3

Word 4

Word 5

Word 6

Word 7

Word 8

Word 9

Word 10

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

0123456789101112131415 012345671011121314151617

Device

(Full logical rack)

Device 2

(3/4 logical rack)

Device 3

(1/4 logical rack)

Device

(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

Scanner

RIO Scan

Processor

DCM

I/O Module

Outputs from PLC, Input Data to DCM

SLC Expansion

Chassis

Outputs from Modules

Output Device

Inputs to PLC, Output Data from DCM

SLC Chassis

Inputs to Modules

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

Chapter

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.

Required Tools and Equipment

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

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.

Select

a scanner

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.

Catalog Number

➀

1747-SN

➁

1771-SN 1772-SD, -SD2

➂➃

1775-S4A, -S4B, -S5 1775-SR, -SR5 1785-L11B 1785-LT/x 1785-L20B 1785-LT2 1785-L30x 1785-L40x 1785-L60x 5250-RS 6008-SI 6008-SV

➀

➀➄

➀

➀➄

➀ ➀ ➀

➀

SLC Remote I/O Scanner Sub I/O scanner for Mini–PLC-2r and PLC-5 families Remote scanner/distribution panel for PLC-2 family I/O scanner-programmer interface module for PLC-3r family Remote scanner/distribution panel for PLC-3/10 family PLC 5/11t (in scanner mode)

PLC 5/15 (in scanner mode) PLC 5/20t (in scanner mode) PLC 5/25 (in scanner mode) PLC 5/30t (in scanner mode) PLC 5/40t (in scanner mode) PLC 5/60t (in scanner mode) Remote scanner for PLC 5/250 IBMr PC I/O Scanner Module VMEbus I/O Scanner Module

6008-SQH1, -SQH2 Q-bus I/O Scanner Module

Description

Reference

–

Reference

The manual for

the scanner you

select

2–2

➀

Extended

➁

Revision D or later

➂

Rev

➃

Extended node capability not available with Series A.

➄

node capability

. 3 or later

Rev.

3 or later

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

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

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

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

Choose

Configure your system by setting the DIP switches.

the type of slot addressing you will use.

Configure

Insert

the 1747-DCM module into the chassis.

1 data word (16 bits of I/O

3 data words (48 bits of I/O

5 data words (80 bits of I/O

7 data words (112 bits of I/O

the module using the DIP switches.

Then: Including the Status Word

data) are transferred.

Total transfer = 2 words

Total transfer = 4 words

Total transfer = 6 words

Total transfer = 8 words

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.

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

Review Make sure system power is off; then insert the DCM into your 1746 chassis. In this example

procedure, local slot 1 is selected.

Module Release

Card Guide

. . .

Cable Tie

Chapter 5

(Installation and

Wiring)

2–3

Chapter 2

Usin

xtende

apabilit

xtende

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:

Baud Rate

g E

Node C

Not Using E

d Nod

Capability

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

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.

57.6K baud 3048 meters (10,000 feet)

115.2K baud 1524 meters (5,000 feet)

230.4K baud

57.6K baud 3048 meters (10,000 feet)

115.2K baud 1524 meters (5,000 feet)

230.4K baud 762 meters (2,500 feet)

Enter

through the system start-up procedure.

Maximum Cable Distance

(Belden 9463)

762 meters (2,500 feet)

your ladder program.

Resistor Size

2W 1/2 Watt

Brown–Green–Brown–Gold

50W 1/2 Watt

Brown–Green–Brown–Gold 82W 1/2 Watt

Gray–Red–Black–Gold

Reference

Chapter 6

(Programming)

Chapter 8

(Application

Examples)

Reference

–

2–4

Chapter

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.

Addressing Ladder Logic Instructions

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: SLC Processors 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.

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.

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.

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

Octal

171615141312111076543210

Bit Number

Group 0 Group 1 Group 2

Rack

Group 3 Group 4 Group 5 Group 6 Group 7

Logical

Decimal

Bit Number

Word 0 Word 1 Word 2 Word 3 Word 4 Word 5 Word 6 Word 7

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.

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

Physica

Slot

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

O:017/10I:023/10

I = Input

02 = Logical Rack

3 = 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.

O = Output

01 = Logical Rack

7 = I/O Group

10 = Bit (octal)

3–2

Chapter 3

Addressing

SLC Addresses

The three parts of the SLC address include the:

• physical slot

• word

• bit

SLC Input

Address

SLC Output

Address

O:1.7/8I:2.3/8

I = Input

2 = Physical Slot 3 = 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.

O = Output

1 = Physical Slot

7 = Word

8 = Bit (decimal)

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

15 14 13 12 11 10 7 6 5 4 3 2 1 098 17 16 15 14 13 12 7 6 5 4 3 2 1 011 10Octal

PLC Output Image T

Reserved for Status W

O:011/10

O = Output

01 = Logical Rack

1 = Logical I/O Group

10 = Bit (octal)

able

ord

DCM Input Image T

Decimal 15 14 13 12 11 10 7 6 5 4 3 2 1 098 Decimal 15 14 13 12 11 10 7 6 5 4 3 2 1 098

Status W

Word 0

Word 1

Word

Word 3

Word 4

Word 5

Word 6

Word 7

Reserved for Status W

ord

able

ord

Word 0 Word 1 Word 2 Word 3 Word 4 Word 5 Word 6 Word 7

SLC Input Image T

Status W

Reserved for Status W

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

ord

able

ord

I:1.1/8

Decimal

15 14 13 12 11 10 7 6 5 4 3 2 1 098 17 16 15 14 13 12 7 6 5 4 3 2 1 011 10Octal

3–4

PLC Input Image T

Status W

Reserved for Status W

I = Input

01 = Logical Rack

6 = Logical I/O Group

2 = Bit (octal)

ord

able

ord

I:016/2

DCM Output Image T

Decimal 15 14 13 12 11 10 7 6 5 4 3 2 1 098 Decimal 15 14 13 12 11 10 7 6 5 4 3 2 1 098

Status W

Word 0

Word 1

Word

Word 3

Word 4

Word 5

Word 6

Word 7

Reserved for Status W

ord

able

ord

Word 0 Word 1 Word 2 Word 3 Word 4 Word 5 Word 6 Word 7

SLC Output Image T

Reserved Status W

Reserved for Status W

O = Output

1 = Physical DCM Slot 6 = Word

2 = Bit (decimal)

able

ord

O:1.6/2

Chapter 3

Addressing

Image Mapping

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 To: DCM SLC Input 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)

→

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:

DCM

DCM 2

DCM 3

Octal 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

Group 0 Group 1

Group 2 Group 3

Group 4 Group 5 Group

Group 7

17 16

10 9

13 12 11 8 7 6 5 4 3 2 1 015 14Decimal

Reserved for Status W

ord

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 7 6 5 4 3 2 1 098

Word 0

Word 1

Word

Word 3

Word 4

Word 5

Word 6

Word 7

Reserved for Status W

SLC 2 Input Image for DCM 2

Bit

Number: Decimal

15 14 13 12 11 10 7 6 5 4 3 2 1 098

Word

Word 1

Reserved for Status W

SLC 3 Input Image for DCM 3

Bit

Number: Decimal

15 14 13 12 11 10 7 6 5 4 3 2 1 098

Word 0

Word 1 Word 2

Word 3

Reserved for Status W

ord

I:1.1/8 (Slot

1, Word 1, Bit 8 Decimal)

I:1.1/3 (Slot 1, Word 1, Bit 3 Decimal)

I:1.3/11 (Slot 2, W

ord 3, Bit 1

1 Decimal)

Distributed SLC Processor 1

Distributed SLC Processor 2

Distributed SLC Processor 3

DCM 1

Module 1 Configured As:

Rack Address 1

Slot Number 1

DCM 2

Module 2 Configured As:

Rack Address 2

Slot Number 1

DCM 3

Module 3 Configured As:

Rack Address 2

Slot Number 2

I/O Group

Rack Size Full

I/O Group

Rack Size 1/4

I/O Group

Rack Size 1/2

3–6

Chapter

Module Configuration

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

• DIP switches

• DIP switch 1 settings

• DIP switch 2 settings

DIP Switches

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.

DIP

Starting I/O Group Number

Rack Address

Reserved

Rack

Size

Last Rack

Clear On Fault

Data Rate

1234567

SW1

1234567

SW2

Switch 1

(SW1)

DIP Switch 2

(SW2)

SW1

2345678 1

234567 8 1

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 Number of RIO Words Transferred Total Words

1/4 Logical Rack 1 Status and 1 Data 2 1/2 Logical Rack 1 Status and 3 Data 4 3/4 Logical Rack 1 Status and 5 Data 6

Full Logical Rack 1 Status and 7 Data 8

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

Starting I/O Group Number SW1-7 SW1-8 Valid Rack Configuration

0 ON ON All 2 ON OFF 3/4, 1/2, 1/4 4 OFF ON 1/2, 1/4 6 OFF OFF 1/4

Starting Group 0 Starting Group 2

Starting Group 6

Example of different starting groups:

Octal

Bit Number:

Group Group 1, Word 1 Group 2, Word 2 Group 3, Word 3 Group 4, Word 4 Group 5, Word 5 Group 6, Word 6 Group 7, Word 7

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

0, W

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

ord 0

A SS T T U W O R D

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.

DCM 1 Rack Size = 1/4 Rack

DCM 2 Rack Size = 1/2 Rack

DCM 3 Rack Size = 1/4 Rack

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

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

1747-SNPLC-2PLC-3PLC-

0 1 0 – – – – 0 ON ON ON ON ON ON

1 2 1 1 1 1 1 1 ON ON ON ON ON OFF

2 3 2 2 2 2 2 2 ON ON ON ON OFF ON

3 4 3 3 3 3 3 3 ON ON ON ON OFF OFF

5 4 4 4 4 4 ON ON ON OFF ON ON

6 5 5 5 5 5 ON ON ON OFF ON OFF

7 6 6 6 6 6 ON ON ON OFF OFF ON

Logical Rack Number (Octal) Switch Number (SW1)

7 7 7 7 7 ON ON ON OFF OFF OFF

10 10 10 10 ON ON OFF ON ON ON

11 11 11 11 ON ON OFF ON ON OFF

12 12 12 12 ON ON OFF ON OFF ON

13 13 13 13 ON ON OFF ON OFF OFF

14 14 14 14 ON ON OFF OFF ON ON

15 15 15 15 ON ON OFF OFF ON OFF

16 16 16 16 ON ON OFF OFF OFF ON

17 17 17 17 ON ON OFF OFF OFF OFF

20 20 20 ON OFF ON ON ON ON

21 21 21 ON OFF ON ON ON OFF

22 22 22 ON OFF ON ON OFF ON

23 23 23 ON OFF ON ON OFF OFF

24 24 24 ON OFF ON OFF ON ON

25 25 25 ON OFF ON OFF ON OFF

26 26 26 ON OFF ON OFF OFF ON

27 27 27 ON OFF ON OFF OFF OFF

30 30 ON OFF OFF ON ON ON

31 31 ON OFF OFF ON ON OFF

32 32 ON OFF OFF ON OFF ON

33 33 ON OFF OFF ON OFF OFF

34 34 ON OFF OFF OFF ON ON

35 35 ON OFF OFF OFF ON OFF

36 36 ON OFF OFF OFF OFF ON

37 37 ON OFF OFF OFF OFF OFF

40 OFF ON ON ON ON ON

41 OFF ON ON ON ON OFF

42 OFF ON ON ON OFF ON

43 OFF ON ON ON OFF OFF

44 OFF ON ON OFF ON ON

5/15

PLC-

5/25

PLC-

5/40

PLC-

5/60

PLC-

1 2 3 4 5 6

5/250

4–4

Continued on next page.

Chapter 4

Module Configuration

1747-SNPLC-2PLC-3PLC-

45 OFF ON ON OFF ON OFF

46 OFF ON ON OFF OFF ON

47 OFF ON ON OFF OFF OFF

50 OFF ON OFF ON ON ON

51 OFF ON OFF ON ON OFF

52 OFF ON OFF ON OFF ON

53 OFF ON OFF ON OFF OFF

54 OFF ON OFF OFF ON ON

55 OFF ON OFF OFF ON OFF

56 OFF ON OFF OFF OFF ON

57 OFF ON OFF OFF OFF OFF

60 OFF OFF ON ON ON ON

61 OFF OFF ON ON ON OFF

62 OFF OFF ON ON OFF ON

63 OFF OFF ON ON OFF OFF

64 OFF OFF ON OFF ON ON

65 OFF OFF ON OFF ON OFF

66 OFF OFF ON OFF OFF ON

67 OFF OFF ON OFF OFF OFF

70 OFF OFF OFF ON ON ON

71 OFF OFF OFF ON ON OFF

72 OFF OFF OFF ON OFF ON

73 OFF OFF OFF ON OFF OFF

74 OFF OFF OFF OFF ON ON

75 OFF OFF OFF OFF ON OFF

76 OFF OFF OFF OFF OFF ON

77 77 77 77 77 77 77 77 Reserved

5/15

PLC-

5/25

PLC-

5/40

PLC-

5/60

PLC-

1 2 3 4 5 6

5/250

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 SW2-5 SW2-6

1/4 Logical Rack ON ON 1/2 Logical Rack ON OFF 3/4 Logical Rack OFF ON Full Logical Rack OFF 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 SW2-4

Yes OFF

Logical Rack

SLC

Bit Number:

Module Module 2

Module 3 Module 4

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

Group

0, W

Group 1, Word 1 Group 2, Word 2 Group 3, Word 3 Group 4, Word 4 Group 5, Word 5 Group 6, Word 6 Group 7, Word 7

ord 0

Module 4 is the last device in the logical rack.

13 12 11 10 9 8 7 6 5 4 3 2 1 015 14Decimal

17 16

No ON

Remote I/O Scanner

Output Image (to the PLC)

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.

Direct Communications Module 1

Module 1 Configured As:

Logical Rack Address 1 I/O Group 0 Module Rack Size 1/4

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

4–6

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 SW2-3

Yes OFF

No 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 SW2-1 SW2-2 Cable Length (Belden 9463)

57.6K baud ON ON 3048 meters (10,000 feet)

115.2K baud ON OFF 1524 meters (5,000 feet)

230.4K baud

OFF ON

62 meters (2,500 feet)

OFF OFF

4–7

Chapter

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

Compliance to European Union Directives

DCM Installation

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

Cable Tie

19627

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

xten e o e

Installation and Wiring

Network Wiring

CONFIGURATION

RACK ADDR

1/4 1/2 3/4 1

RIO Link Connector

LINE 1 _______ SHIELD ______ LINE 2 _______

Using Extended Node Capability

Not Using

Extended Node

Capability

DCM

FAULT

COMM

RACK SIZE

FIRST I/O GROUP 0 2 4 6

DATA RATE (K B/S)

57.6 115.2 230.4

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 Terminating Resistor Size

All Baud Rates

57.6K baud

115.2K baud

230.4K baud

RIO

I/O

GROUP

(LSB)

SW1

RACK

ADDRESS

2345678

(MSB)

X X

RACK SIZE

SW2

LAST

RACK

CLR ON FL

2345678

DATA RATE

1747-DCM Direct Communication Module

82W 1/2 Watt

150W 1/2 Watt 150W 1/2 Watt

82W 1/2 Watt

Scanner

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

Line 1 – Blue

Shield – Shield

Line 2 – Clear

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

Chapter

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

Overview

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

]/[

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.

Power Supply

Physical Slot #

Output

SLC Processor

0123456

Input

DCM 1

Physical Input into PLC – Physical Output from SLC

PLC

Input Output

PLC

Processor

SLC

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.

Scanner

I:000

] [

RIO

O:021

( )

I:3.1

] [

DCM

I:3.0

]/[

Logical Or Status Bit

SLC

Processor

O:1.0

( )

OUT

6–2

Chapter 6

Programming

Physical Input into SLC – Physical Output from PLC

RIO

Input Output

SLC

Processor

I:2.0

SLC

] [

DCM

O:3.1

( )

I:021

PLC

] [

Logical Or Status Bit

RIO

I:020

]/[

Scanner

O:001

( )

PLC

Processor

OUT

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

Input

PLC

Processor

RIO

Scanner

RIO

DCM

SLC

Processor

Input

Output

PLC

SLC

I:000

] [

I:2.0

] [

O:021

( )

I:3.1

] [

I:3.0

]/[

Logical Or Status Bit

O:1.0

( )

OUTIN

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

I:2.0

SLC

] [

PLC

(No physical input into the PLC)

O:3.1

( )

I:021

] [

I:020

]/[

Logical Or Status Bit

I:4.1

] [

O:031

( )

I:4.0

]/[

Logical Or Status Bit

O:1.0

( )

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

Bit Number: Decimal

Status Word:

Data Words:

Status Word:

Data 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 Number of RIO Words Transferred Total Words

1/4 Logical Rack One (plus one Status Word) 2 1/2 Logical Rack Three (plus one Status Word) 4 3/4 Logical Rack Five (plus one Status Word) 6 Full Logical Rack Seven (plus one Status Word) 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.

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

RRRRRRRR

DCM 1 1/2 Rack Device

RRRRRRRR

DCM 2 1/2 Rack Device

Word Word 1 Word 2 Word 3 Word 4 Word 5 Word 6 Word 7

DCM

Reserved Bits Status Bits

= 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.

897

342

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

SLC

PLC

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.

897

10117

342

Reserved Bits 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

scanner data being sent from the DCM to the scanner is valid. This occurs because for a brief period after the Program/T

DCM Output Data Invalid bit

. If you use the Program/T

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

est/Fault Mode bit you may incorrectly receive an indication that the SLC

to determine the validity of SLC data sent from the DCM to the

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.

DCM

SLC Rung to Monitor

RIO Scanner Status Bit 09

Conditional

I:3.1

] [

Input

Program/Test/Fault SLC

I:3.0

]/[

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

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)

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

] [

I:020

]/[

O:000

( )

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.

6–8

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.

SLC Rungs

Set User Status Flag Bit

Disable DCM

Enable DCM

Condition(s)

Chapter 6

Programming

➀

➁

User Status Flag Bit

O:13.0

(L)

➂

IOM

IMMEDIATE OUT w MASK Slot 0:3.0 Mask 0800

➃

S2:11

(U)

➃

S2:11

(L)

Clear User Status Flag Bit

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 1

➃

S2:11-S2:12

S2:1

1/0 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

Condition(s)

➁

O:3.0

(U)

➂

1 (decimal); the PLC-5 receives this bit as bit 13 (octal).

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

I:021

] [

I:020

]/[

O:000

( )

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

] [

I:3.0

]/[

O:1.0

( )

6–10

Chapter

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)

DCM Status Indicators

Troubleshooting Using the FAULT LED (Red)

Two LEDs indicate the status of the DCM.

DCM

FAULT

COMM

If LED is: Cause: Corrective action:

On Internal Fault

Blinking Configuration Error

Off Normal State No action required.

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

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. Also see that the setting for rack address is correct. Refer to chapter 4, Module Configuration, for help with DIP switches.

Red

Green

➀

7–1

Chapter 7

Troubleshooting

Troubleshooting Using the COMM LED (Green)

If LED is:

On Normal State No action required.

Blinking

Off

Cause: Corrective action:

RIO scanner’s processor

in Program/Test Fault

Mode

RIO scanner’s processor

not connected to scanner

RIO scanner’s processor

rack inhibited

No communication

between RIO scanner’s

processor and DCM

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

Application Examples

This chapter provides and examines two applications of the DCM.

• basic example

• supplementary example

Basic Example

Rack 1 Rack 2

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.

Output

Input

SLC 5/02

1747-SN Module Configuration

RIO

(Belden 9463)

➀

DCM

SLC 5/01

Output

= slot not used

Baud Rate = 57.6K baud G-file Size = 3 words

G-File

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

Word 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 = 0 Baud Rate = 57.6K baud Clear On Fault = no Last Rack = no Rack Size = 1/4

DIP Switch Settings

Switch 1 Switch 2

1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8

ON X X X X X X X X X X X X X

OFF X

System Configuration for Rack 1

Amount Device Catalog Number

1 Power Supply 1746-P2 1 SLC 5/02 Processor 1747-L524 1 4-Slot Rack 1746-A4 1 AC Input, 16 Inputs 1746-IA16 1 Relay Output, 16 Outputs 1746-OW16 1 Scanner 1747-SN

System Configuration for Rack 2

Amount Device Catalog Number

1 Power Supply 1746-P2 1 SLC 5/01 Processor 1747-L511 1 4-Slot Rack 1746-A4

= Not used

8–2

1 Relay Output, 16 Outputs 1746-OW16 1 DCM 1747-DCM

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

] [

From Input Switch To SN Output

O:3.1

Word 1, Bit 0

Rack 2, Program 2

I:1.1

] [

From DCM Input Word 1, Bit 0

()

O:2

()

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.

I/O

CPU

PLC–5

I/O

RIO

(Belden 9463)

DCM

SLC 5/01

NI4

NO4I

= slot not used

Module Configuration

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

S:27/0

= S:27/1 = 0 S:27/2 = 1 S:27/3 = 1 * = Don’t care

DCM configuration:

Rack Address = 1 I/O Group = 0 Baud Rate = 57.6K baud Clear on Faults = No Last Rack = No Rack Size = Full Rack

8–4

Chapter 8

Application Examples

DIP Switch Settings

Switch 1 Switch 2

1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8

ON X X X X X X X X X X X

OFF X X X

System Configuration

Amount Device Catalog Number

1 Power Supply 1746-P2 1 SLC 5/01 Processor 1747-L511

= Not used

1 7-Slot Rack 1746-A7 2 Analog Input, 4 point 1746-NI4 2 Analog Output, 4 point 1746-NO4I 1 DCM 1747-DCM

Image Table Configuration

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

O:1.0 Status Word to PLC-5 from SLC O:1.1 Counter ACC word denotes module being read O:1.2 Word 0 of analog module being read O:1.3 Word 1 of analog module being read

DCM

O:1.4 O:1.5 Word 3 of analog module being read O:1.6 Counter ACC word denotes module being read O:1.7 Not used O:4.0 NO4I word 0 O:4.1 NO4I word 1

NO4I

O:4.2 O:4.3 NO4I word 3 O:5.0 NO4I word 0 O:5.1 NO4I word 1

NO4I

O:5.2 O:5.3 NO4I word 3

Word 2 of analog module being read

Output Image

NO4I word 2

8–5

Chapter 8

Application Examples

Input Image

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

I:1.0 Status Word to SLC from PLC-5 I:1.1 Not used I:1.2 Not used I:1.3 Not used

DCM

I:1.4

Not used I:1.5 Not used I:1.6 Not used I:1.7 Not used I:2.0 NI4 word 0 I:2.1 NI4 word 1

NI4

I:2.2

NI4 word 2 I:2.3 NI4 word 3 I:3.0 NI4 word 0 I:3.1 NI4 word 1

NI4

I:3.2

NI4 word 2 I:3.3 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

] [

S:1

] [

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.

S:4

RUNG

2.1

] [

5.12 Seconds Time Bit

MOV

MOVE Source 2

Dest C5:0.ACC

CTU

Countup Counter C5:0 Preset 6 Accum 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

RUNG

2.3

EQU

EQUAL Source A C5:0.ACC

Source B 2

Module Number Monitored = 3

EQU

EQUAL Source A C5:0.ACC

Source B 3

MOV

MOVE Source C5:0.ACC

Dest 0:1.1

COP

COPY FILE Source #I:2.0 Dest #0:1.2 Length 4

MOV

MOVE Source C5:0.ACC

Dest 0:1.6

MOV

MOVE Source C5:0.ACC

Dest 0:1.1

COP

COPY FILE Source #I:3.0 Dest #0:1.2 Length 4

MOV

MOVE Source C5:0.ACC

Dest 0:1.6

8–7

Chapter 8

Application Examples

Module Number Monitored = 4

RUNG

2.4

RUNG

2.5

EQU

EQUAL Source A C5:0.ACC

Source B 4

Module Number Monitored = 5

EQU

EQUAL Source A C5:0.ACC

Source B 5

MOV

MOVE Source C5:0.ACC

Dest 0:1.1

COP

COPY FILE Source #I:4.0 Dest #0:1.2 Length 4

MOV

MOVE Source C5:0.ACC

Dest 0:1.6

MOV

MOVE Source C5:0.ACC

Dest 0:1.1

<END>

COP

COPY FILE Source #I:5.0 Dest #0:1.2 Length 4

MOV

MOVE Source C5:0.ACC

Dest 0:1.6

8–8

Module Number Monitored = 2

Chapter 8

Application Examples

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.

RUNG

2.0

RUNG

2.1

RUNG

2.2

EQU

EQUAL Source A I:011

Source B 2

Module Number Monitored = 3

EQU

EQUAL Source A I:011

Source B 3

Module Number Monitored = 4

EQU

EQUAL Source A I:011

Source B 4

EQU

EQUAL Source A I:016

Source B 2

EQU

EQUAL Source A I:016

Source B 3

EQU

EQUAL Source A I:016

Source B 4

COP

COPY FILE Source #I:012

Dest #N7:0 Length 4

COP

COPY FILE Source #I:012

Dest #N7:4 Length 4

COP

COPY FILE Source #I:012

Dest #N7:8 Length 4

RUNG

2.3

Module Number Monitored = 5

EQU

EQUAL Source A I:011

Source B 5

EQU

EQUAL Source A I:016

Source B 5

<END>

COP

COPY FILE Source #I:012

Dest #N7:12 Length 4

8–9

Usin

xtende

apabilit

8 1

xtende

Electrical Specifications

Appendix

Specifications

This appendix provides the following module and system specifications.

• electrical specifications

• environmental specifications

• network specifications

It also discusses throughput time for the DCM.

Backplane Current Consumption 360mA at 5V

Environmental Specifications

Network Specifications

Operating Temperature 0°C to 60°C (32°F to 140°F) Storage Temperature Humidity Rating 5% to 95% noncondensing Agency Certification

(when product or packaging is marked)

Baud Rate

g E

Node C

Not Using

Not Using Extended Node

d Nod

Capability

57.6K baud 10,000 feet at 57.6K baud

115.2K baud 5,000 feet at 115.2K baud

230.4K baud

57.6K baud 3048 meters (10,000 feet)

115.2K baud 1524 meters (5,000 feet)

230.4K baud 762 meters (2,500 feet)

−40°C to +85°

•CSA certified

•CSA Class I, Division 2

Groups A, B, C, D certified

•UL listed

•CE marked for all applicable directives

Maximum Cable Distance

(Belden 9463)

2,500 feet at 230.4K baud

C (

−40°F to +185°F)

82W 1/2 Watt

2W 1/2 Watt

50W 1/2 Watt

82W 1/2 Watt

Resistor Size

A–1

Appendix

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:

I/O circuit delay:

I/O scan time:

Program scan time:

PLC Delay:

SLC Delay:

SLC

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

Appendix

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

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

PLC Output

Address

O:017/10I:023/10

I = Input

02 = Logical Rack

3 = I/O Group

10 = Bit (octal)

O = Output

01 = Logical Rack

7 = I/O Group

10 = Bit (octal)

SLC Addresses

SLC Input

Address

SLC Output

Address

O:1.7/8I:2.3/8

I = Input

2 = Physical Slot 3 = Word

8 = Bit (decimal)

If you configure the DCM as: Then: Including the Status Word

1/4 Rack

1/2 Rack

3/4 Rack

Full Rack

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 = Output

1 = Physical Slot

7 = Word

8 = Bit (decimal)

Total transfer = 2 words

Total transfer = 4 words

Total transfer = 6 words

Total transfer = 8 words

B–1

Appendix B

DCM

Addressing W

1/4

Logical

Rack

1/2

Logical

Rack

orksheet

DCM Input Image Table

PLC Output Rack # SLC Input

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:

I/O Group Bit (octal) Slot # Word Bit (decimal)

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:

B–2

Continued

on next page.

3/4

Logical

Rack

Full

Logical

Rack

DCM Input Image Table (continued)

PLC Output Rack # SLC Input

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:

I/O Group Bit (octal) Slot # Word Bit (decimal)

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:

Appendix B

DCM

Addressing W

orksheet

B–3

Appendix B

DCM

Addressing W

1/4

Logical

Rack

1/2

Logical

Rack

orksheet

DCM Output Image Table

PLC Input Rack # SLC Output

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:

I/O Group Bit (octal) Slot # Word Bit (decimal)

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:

B–4

Continued

on next page.

3/4

Logical

Rack

Full

Logical

Rack

DCM Output Image Table (continued)

PLC Input Rack # SLC Output

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:

I/O Group Bit (octal) Slot # Word Bit (decimal)

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:

Appendix B

DCM

Addressing W

orksheet

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

adapter

, 1–4 extended node capability 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

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 W Logical OR bit, 6–10

Program/T User Status Flag bit in the SLC Status

available scanners, 2–2

, P–4

6–7

est/Fault Mode bit in the RIO

scanner status word, 6–7

ord, 6–8

, 1–4

ord,

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 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

, 5–2

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 FAUL

T 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 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

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),

door label, 1–1

, 1–1

SW1-6), 4–3

4–6

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

I–1

Index

Direct Communication Module User Manual

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

of scanners and adapters, 1–4 of the DCM, 1–4 specifications, 2–4, 5–3, A–1

, 1–4

FAUL

T LED, 1–1 flashing LED, 7–2 front label, 1–1 full rack, 2–3, 4–6

getting started, 2–1

procedure, 2–2 glossary terms, P–3 green LED, troubleshooting using, 7–2

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 image mapping, 3–5 inserting the cable tie, 5–2 installation, getting started, 2–1 installing the module, 5–1

, 1–5

labels, front, side and door ladder logic instructions, addressing, 3–1 Last Rack (SW2-4), 4–6 LEDs, 7–1

blinking, 7–1 COMM (green), 7–2 FAUL

T (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

, 1–1

manuals, related, P–2 Module Rack Size (SW2-5 and SW2-6), 4–6 module release, 5–2

I–2

hardware features, 1–1

cable tie slots, 1–1 COMM LED, 1–1 DIP switches, 1–1 FAUL

T LED, 1–1 front, side and door labels, 1–1 RIO link connector self-locking tabs, 1–1

hardware overview

hardware features, 1–1

Hold Last State, in status word applications,

6–7

humidity rating, A–1

, 1–1

network specifications, A–1 network wiring, 5–3

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/T programming examples, 6–2

programming overview publications, related, P–2

est/Fault Mode bit, 6–5, 6–6, 6–7

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

, 6–1

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

removing the module, 5–2 required tools and equipment, 2–1 resistor baud rate, 2–4 RIO adapter RIO communications link, 1–2 RIO link connector 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/T

RIO scanners, 2–2

, 1–1

, 1–2

, 1–1

est/Fault Mode bit, 6–5

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

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

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

, 2–3

, A–1

I–3

Index

Direct Communication Module User Manual

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

Size, 4–6

system overview

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

, 1–2

temperature specifications, A–1

operating, A–1 storage, A–1

terminating resistor terms, P–3

, size of, 5–3

throughput timing, A–2 tools needed, 2–1 troubleshooting, 7–1

contacting Allen-Bradley using the COMM LED (green), 7–2 using the F

AUL

T LED (red), 7–1

, P–4

User Status Flag bit, 6–6, 6–8

wiring the network, 5–3 word address, 3–3 worksheets, B–1

I–4

Worldwide representation.

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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ugoslavia

•Switzerland • Taiwan •

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

Publication

Supersedes

1747-6.8 – June 1996

Publication 1747-NM007 – September 1993

Publication

Ireland •

Israel • Italy •

Thailand • T

40072-032-01(A)

1747-6.8 – June 1996

, Inc. Printed in USA

urkey

•

Rockwell Automation 1747-DCM, D17476.8 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Important User Information

Summary of Changes

New Information

Preface

Who Should Use this Manual

Purpose of this Manual

Terms and Abbreviations

Common Techniques Used in this Manual

Allen–Bradley Support

• hardware overview

Data Exchange Between RIO Scanners and the DCM

Required Tools and Equipment

Procedures

Addressing Ladder Logic Instructions

Image Mapping

DIP Switches

DIP Switch 1 Settings

DIP Switch 2 Settings

Compliance to European Union Directives

DCM Installation

Network Wiring

Overview

Programming Examples

Status Words

Applications Using I/O Status Word Bits

DCM Status Indicators

Troubleshooting Using the FAULT LED (Red)

Troubleshooting Using the COMM LED (Green)

Basic Example

Supplementary Example

Electrical Specifications

Environmental Specifications

Network Specifications

Throughput Timing

Directions

Addressing Review

Index