Allen-Bradley ControlLogix 1756-DHRIO User manual

ControlLogix Data
Highway
Plus-Remote I/O
Communication
Interface Module
1756-DHRIO
User Manual

Important User Information
Because of the variety of uses for the products described in this
publication, those responsible for the application and use of these
products must satisfy themselves that all necessary steps have been
taken to assure that each application and use meets all performance
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codes and standards. In no event will Rockwell Automation be
responsible or liable for indirect or consequential damage resulting
from the use or application of these products.
Any illustrations, charts, sample programs, and layout examples
shown in this publication are intended solely for purposes of
example. Since there are many variables and requirements associated
with any particular installation, Rockwell Automation does not assume
responsibility or liability (to include intellectual property liability) for
actual use based upon the examples shown in this publication.
Allen-Bradley publication SGI-1.1, Safety Guidelines for the
Application, Installation and Maintenance of Solid-State Control
(available from your local Rockwell Automation office), describes
some important differences between solid-state equipment and
electromechanical devices that should be taken into consideration
when applying products such as those described in this publication.
Reproduction of the contents of this copyrighted publication, in whole
or part, without written permission of Rockwell Automation, is
prohibited.
Throughout this publication, notes may be used to make you aware of
safety considerations. The following annotations and their
accompanying statements help you to identify a potential hazard,
avoid a potential hazard, and recognize the consequences of a
potential hazard:
Allen-Bradley is a trademark of Rockwell Automation
WARNING
!
Identifies information about practices or
circumstances that can cause an explosion in a
hazardous environment, which may lead to personal
injury or death, property damage, or economic loss.
ATTENTION
!
Identifies information about practices or
circumstances that can lead to personal injury or
death, property damage, or economic loss.
IMPORTANT Identifies information that is critical for successful
application and understanding of the product.

1Publication 1756-UM514B-EN-P - February 2003
Summary of Changes
Introduction
This release of this document contains new and updated information.
To find new and updated information, look for change bars, as shown
next to this paragraph.
Updated Information
The following changes were made in this release of the manual:
·The manual has been reorganized to keep specific
information together.
–DH+ information (e.g. description of DH+ operation, software
usage in DH+ applications, DH+ examples) is grouped
together in Chapters 2 through 8.
–Remote I/O and block transfer information is grouped
together in Chapters 9 through 13.
For a full description of the manual’s organization, see
Table Preface.1 on page Preface-2 or the Table of Contents.
·The description of how to use software with 1756-DHRIO
module is expanded, as follows:
–Chapter 3 explains Using Programming Software in
DH+ Applications.
–Chapter 9 explains Using RSLogix 5000 in Remote I/O and
Block Transfer Applications.
·Appendix C, Application Guidelines and Tips, has been
included in the manual to assist you in improving the
performance of your 1756-DHRIO module.

Publication 1756-UM514B-EN-P - February 2003
Summary of Changes 2
Notes:

1Publication 1756-UM514B-EN-P - February 2003
Preface
Purpose of This Manual
This manual describes how to understand, configure and troubleshoot
your ControlLogix Data Highway Plus/Remote I/O communication
interface module (1756-DHRIO module).
This manual also provides step-by-step procedures on how to:
·use the 1756-DHRIO module to send DH+ messages between
ControlLogix controllers, PLCs and SLCs in DH+ applications.
and
·connect ControlLogix controllers to remote I/O and send block
transfers via the 1756-DHRIO module.
Throughout this manual, we describe ControlLogix systems that use
the 1756-DHRIO module and ControlLogix controllers. Multiple
ControlLogix controllers are available. The examples contained in this
manual do not call out specific catalog numbers for ControlLogix
controllers. Whenever a controller is shown, any of the
controllers apply.
For a complete list of ControlLogix controllers, and a description of
each, see the ControlLogix Selection Guide, publication 1756-SG001.
Who Should Use This
Manual
This manual is intended for those individuals who program
applications that use 1756-DHRIO modules, such as:
·software engineers
·control engineers
·application engineers
·instrumentation technicians
We assume you have a good understanding of the Data Highway Plus
protocol and Remote I/O. This user manual contains a brief
description of Data Highway Plus in Chapter 2 and a brief description
of Remote I/O in Chapters 10 & 11.

Publication 1756-UM514B-EN-P - February 2003
Preface 2
Information Found in
This Manual
This manual is broken into three parts:
·General module information - Chapters 1 and 14, Appendices A
to C
·DH+ information - Chapters 2 to 8
·Remote I/O and Block Transfer Information - Chapters 9 to 13
Table Preface.1 lists the information that is available in each section of
this manual.
Table Preface.1
Section Title
General
Module
Information
Chapter 1 1756-DHRIO Module Description
DH+
Information
Chapter 2 Using the Data Highway Plus Network
Chapter 3 Using Programming Software in DH+ Applications
Chapter 4 Messaging Between PLC-5s and SLC-5/04s
Chapter 5 Messaging Between PLC-5s or SLC5/04s and
ControlLogix Controllers
Chapter 6 Messaging Between ControlLogix Controllers and
PLC-5s or SLC-5/04s
Chapter 7 Messaging Between ControlLogix Controllers
Remote I/O and
Block Transfer
Information
Chapter 8 Using the 1756-DHRIO Module in
Remote I/O Applications
Chapter 9 Using RSLogix 5000 in Remote I/O and Block
Transfer Applications
Chapter 10 Connecting a ControlLogix Controller to Remote
I/O
Chapter 11 Block Transfers with the 1756-DHRIO Module
General
Module
Information
Chapter 12 Troubleshooting the 1756-DHRIO Module
Appendix A Specifications
Appendix B PCCC Commands Supported by the Data Highway
Plus Module
Appendix C Application Guidelines and Tips

iPublication 1756-UM514B-EN-P - February 2003
Table of Contents
Chapter 1
1756-DHRIO Module Description What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 1-1
What the Module Does . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Routing Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
DH+ and CIP Messaging . . . . . . . . . . . . . . . . . . . . . . . 1-2
Remote I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Module Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Setting Switches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Alphanumeric Indicators . . . . . . . . . . . . . . . . . . . . . . 1-6
Preventing Electrostatic Discharge . . . . . . . . . . . . . . . . . . . 1-7
Removal and Insertion Under Power . . . . . . . . . . . . . . . . . 1-7
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 1-8
Chapter 2
Using the Data Highway
Plus Network
What is Data Highway Plus? . . . . . . . . . . . . . . . . . . . . . . . 2-1
Link Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Trunk Line/Drop Line Considerations . . . . . . . . . . . . . . 2-2
Programming Terminal Port . . . . . . . . . . . . . . . . . . . . . 2-3
Connecting Devices to the DH+ Network. . . . . . . . . . . . . . 2-4
Application Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Two Methods of Communication Over DH+ . . . . . . . . . . . 2-6
Using DH+ Messaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Local DH+ Messaging. . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Remote DH+ Messaging . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Configuration Information in DH+ Messaging. . . . . . . . . . . 2-14
Generating Configuration Faults . . . . . . . . . . . . . . . . . . 2-14
Application Timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Example DH+ Routing Configuration . . . . . . . . . . . . . . . . . 2-16
Using Control and Information Protocol (CIP) Messaging . . 2-17
Limitations of CIP Messaging . . . . . . . . . . . . . . . . . . . . 2-18
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 2-18
Chapter 3
Using Programming Software in
DH+ Applications
Using This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Choosing the Correct Software. . . . . . . . . . . . . . . . . . . . . . 3-1
Using RSLinx to Create a Routing Table . . . . . . . . . . . . . . . 3-2
What Is a Routing Table? . . . . . . . . . . . . . . . . . . . . . . . 3-2
Pyramid Integrator Emulation . . . . . . . . . . . . . . . . . . . . 3-3
ControlLogix Routing . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Creating the Routing Table . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Setting the Controller Slot. . . . . . . . . . . . . . . . . . . . . . . 3-7
Using RSLinx Software to Send Control and
Information Protocol Messages . . . . . . . . . . . . . . . . . . . . . 3-8
Using RSLogix 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Using RSLogix 500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

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Table of Contents ii
Using RSLogix 5000. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Defining Connection Paths . . . . . . . . . . . . . . . . . . . . . . . . 3-20
Connection path examples . . . . . . . . . . . . . . . . . . . . . . 3-21
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 3-24
Chapter 4
Messaging Between PLC-5s
and SLC-5/04s
DH+ Messaging: PLC-5s With One 1756-DHRIO . . . . . . . . . 4-2
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 4-3
Set-Up a Routing Table for the 1756-DHRIO Module . . . 4-3
Configure Message Instructions . . . . . . . . . . . . . . . . . . 4-4
DH+ Messaging: SLC-5/04s With Two 1756-DHRIOs in One
ControlLogix Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 4-6
Set-Up a Routing Table for the 1756-DHRIO Modules . . 4-6
Configure Message Instructions . . . . . . . . . . . . . . . . . . 4-7
DH+ Messaging: PLC-5s With Multiple ControlLogix Chassis 4-8
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 4-9
Set-Up Routing Tables for the 1756-DHRIO Modules . . . 4-10
Configure Message Instructions . . . . . . . . . . . . . . . . . . 4-11
DH+ Messaging: PLC-5 to PLC-5/C on ControlNet. . . . . . . . 4-12
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 4-13
Set-Up a Routing Table for the 1756-DHRIO Module . . . 4-13
Configure Message Instructions . . . . . . . . . . . . . . . . . . 4-14
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 4-14
Chapter 5
Messaging Between PLC-5s or
SLC5/04s and ControlLogix
Controllers
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 5-1
DH+ Messaging: PLC-5 to One ControlLogix Controller
With One ControlLogix Chassis . . . . . . . . . . . . . . . . . . . . . 5-2
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 5-3
Set-Up a Controller Slot for the 1756-DHRIO Module. . . 5-3
Configure Message Instructions . . . . . . . . . . . . . . . . . . 5-4
DH+ Messaging: PLC-5 to Multiple ControlLogix Controllers in
One ControlLogix Chassis . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 5-6
Set-Up a Controller Slot for the 1756-DHRIO Module. . . 5-6
Set-Up a Routing Table for the 1756-DHRIO Module . . . 5-7
Configure Local Message Instructions . . . . . . . . . . . . . . 5-7
Configure Remote Message Instructions . . . . . . . . . . . . 5-8
DH+ Messaging: SLC-5/04 to a ControlLogix Controller With
Multiple ControlLogix Chassis . . . . . . . . . . . . . . . . . . . . . . 5-9
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 5-10
Set-Up a Routing Table for the 1756-DHRIO Module . . . 5-10
Configure Message Instructions . . . . . . . . . . . . . . . . . . 5-11
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 5-11

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Table of Contents iii
Chapter 6
Messaging Between ControlLogix
Controllers and PLC-5s or
SLC-5/04s
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 6-1
Local DH+ Messaging: ControlLogix Controller in a
Single Chassis to a PLC-5. . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 6-3
Configure Message Instructions . . . . . . . . . . . . . . . . . . 6-3
DH+ Messaging: ControlLogix Controller to a SLC-5/04 Over
ControlNet and DH+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 6-5
Set-Up a Routing Table for the 1756-DHRIO Module . . . 6-5
Configure Message Instructions . . . . . . . . . . . . . . . . . . 6-6
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 6-6
Chapter 7
Messaging Between ControlLogix
Controllers
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 7-1
CIP Messaging Between ControlLogix Controllers
Over One Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 7-2
Configure Message Instructions . . . . . . . . . . . . . . . . . . 7-2
CIP Message Routing Between ControlLogix Controllers
Over Two Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Set the Module Switches. . . . . . . . . . . . . . . . . . . . . . . . 7-4
Configure Message Instructions . . . . . . . . . . . . . . . . . . 7-4
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 7-4
Chapter 8
Using the 1756-DHRIO Module in
Remote I/O Applications
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 8-1
Introduction to Remote I/O . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Selecting Devices That You Can Connect . . . . . . . . . . . . . . 8-3
Designing a Remote I/O Network . . . . . . . . . . . . . . . . . . . 8-4
Network Design Guidelines . . . . . . . . . . . . . . . . . . . . . 8-4
Cable Design Guidelines . . . . . . . . . . . . . . . . . . . . . . . 8-5
Trunk Line/Drop Line Considerations . . . . . . . . . . . . . . 8-5
1756-DHRIO Module Operation in a
Remote I/O Application . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Exchanging I/O Data Between the 1756-DHRIO Module
and Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Exchanging I/O Data Between the 1756-DHRIO Module and
the ControlLogix Controller . . . . . . . . . . . . . . . . . . . . . 8-8
I/O Configuration Tree in RSLogix 5000
Controller Organizer . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Remote I/O Scanner Status . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Adapter Module I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

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Table of Contents iv
Setting the Data Exchange Rate Between the
1756-DHRIO Module and a Controller . . . . . . . . . . . . . . . . 8-11
Requested Packet Interval (RPI) . . . . . . . . . . . . . . . . . . 8-11
RIO Scanner Status Update Rate With the 1756-DHRIO in a
Local Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
RIO Scanner Status Update Rate With the 1756-DHRIO
Module in a Remote Chassis. . . . . . . . . . . . . . . . . . . . . 8-11
Setting the Baud Rate. . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
Adapter Module I/O Update Rate with the 1756-DHRIO
Module in the Local Chassis . . . . . . . . . . . . . . . . . . . . . 8-14
Adapter Module I/O Update Rate with the 1756-DHRIO
Module in the Remote Chassis . . . . . . . . . . . . . . . . . . . 8-15
Remote I/O Scanner Fault Notification . . . . . . . . . . . . . . . . 8-16
Remote I/O Adapter Failure Notification . . . . . . . . . . . . . . 8-17
Inhibiting the 1756-DHRIO Module Connections . . . . . . . . 8-17
Inhibiting an Remote I/O Connector Adapter . . . . . . . . . . . 8-17
Increased Remote I/O System Throughput . . . . . . . . . . . . . 8-18
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 8-18
Chapter 9
Using RSLogix 5000 in Remote I/O
and Block Transfer Applications
Using This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Using RSLogix 5000 in 1756-DHRIO Module
Remote I/O Applications . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Adding the 1756-DHRIO Module . . . . . . . . . . . . . . . . . 9-2
Configuring the 1756-DHRIO Module . . . . . . . . . . . . . . 9-3
Adding the Remote I/O Adapter . . . . . . . . . . . . . . . . . . 9-5
Configuring the Remote I/O Adapter . . . . . . . . . . . . . . 9-6
Downloading the Project to the Controller . . . . . . . . . . 9-8
Editing Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Using RSLogix 5000 in 1756-DHRIO Module
Block Transfer Applications. . . . . . . . . . . . . . . . . . . . . . . . 9-9
Adding the 1756-DHRIO Module . . . . . . . . . . . . . . . . . 9-10
Configuring the 1756-DHRIO Module . . . . . . . . . . . . . . 9-11
Adding the Remote I/O Adapter . . . . . . . . . . . . . . . . . . 9-13
Configuring the Remote I/O Adapter . . . . . . . . . . . . . . 9-14
Adding the Remote I/O Modules . . . . . . . . . . . . . . . . . 9-16
Configuring the Remote I/O Modules . . . . . . . . . . . . . . 9-17
Creating a Block Transfer (Read or Write)
Message Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-18
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . 9-22