Rockwell Automation 1785-CHBM User Manual
ControlNet PLC-5
Hot Backup System
Cat. No. 1785-CHBM
User Manual
Important User Information
Because of the variety of uses for the products described in this
publication, those responsible for the application and use of these
products must satisfy themselves that all necessary steps have been taken
to assure that each application and use meets all performance and safety
requirements, including any applicable laws, regulations, codes and
standards. In no event will 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.
TM
Allen-Bradley
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.
publication SGI-1.1, Safety Guidelines for the
Throughout this publication, notes may be used to make you aware of
safety considerations. The following annotations and their accompanying
statements help you to identify a potential hazard, avoid a potential
hazard, and recognize the consequences of a potential hazard
WARNING
Identifies information about practices or circumstances
that can cause an explosion in a hazardous
environment, which may lead to personal injury or
death, property damage, or economic loss.
:
!
ATTENTION
Identifies information about practices or circumstances
that can lead to personal injury or death, property
damage, or economic loss.
!
IMPORTANT
Identifies information that is critical for successful
application and understanding of the product.
PLC-5 is a registered trademark of Rockwell Automati on, Inc.
Allen-Bradley, ControlLogix, ControlBus, Data Highway Plus, FLEX I/O, RSLinx, RSLogix , RSNetWorx, PLC-5/40 and PLC-5/80 are trademarks of
Rockwell Automation, Inc.
ControlNet is a trademark of ControlNet International , Ltd.
DeviceNet is a trademark of the Open DeviceNet Vendor Ass ociation.
Ethernet is a registered trademark of Digital Equipment Company, Intel and Xerox Corporation.
Rockwell Automation Support
Before you contact Rockwell Automation for technical assistance, we
suggest you please review the troubleshooting information contained
in this publication first.
If the problem persists, call your local Rockwell Automation
representative or contact Rockwell Automation in one of the
following ways:
Phone United
States/Canada
Outside United
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Your Questions or Comments on this Manual
If you find a problem with or have a comment on this manual, please
notify us of it on the enclosed How Are We Doing form.
Notes
Preface
Manual Objectives
This manual shows you how to set up and apply a ControlNetTM
®
PLC-5
standard PLC-5/40
Hot Backup system. A backup system requires a pair of
TM
or PLC-5/80TM ControlNet programmable
controllers (Series F, Revision A or higher), with I/O remotely
connected to both PLC-5s via ControlNet.
IMPORTANT
For the ControlNet PLC-5 programmable controllers
to operate in backup mode, each PLC-5 must have a
new ControlNet Backup Cartridge (Cat. No.
1785-CHBM) inserted into its EEPROM memory
module slot.
Using ControlNet, the PLC-5s communicate with each other and with
ControlNet remote I/O to create a PLC-5 backup system that provides
high availability of control applications, where it is essential for
process continuity.
In this manual, we describe the following details of the ControlNet
Hot Backup system:
• system concepts
• required hardware and software components
• installation and configuration procedures
• system operation
• troubleshooting and diagnostics procedures
• system design considerations
Who Should Use This
Before you read this manual or attempt to use the ControlNet PLC-5
backup system, you should be familiar with the use and operation of
Manual
the ControlNet PLC-5 programmable controller. You should also be
familiar with:
• Remote I/O
• the ControlNet network
• RSLogix 5
• RSNetWorx
• RSLinx
1 Publication 1785-UM024B-EN-P - January 2003
TM
programming software
TM
for ControlNet software
TM
communications software
Preface 2
What This Manual Contains
Refer to the following table to guide you through the information
contained in this manual.
For information on: Refer to chapter/appendix:
concepts for using a backup system in a
ControlNet system; basic system
architecture
the hardware and software components
required for a backup system
installing backup system components;
configuring the backup system
how to use I/O in your hot backup system 4 - Using I/O In Your ControlNet Hot Backup
the diagnostic capabilities of the backup
system; troubleshooting tips for the backup
system
specifications for the 1785-CHBM module A - Specifications
backup states and backup state transitions B - Backup States
the data table crossloading feature C - Data Table Crossloading
the program synchronization feature D - Program Synchronization
1 - Backup Concepts for the ControlNet PLC-5
Backup System
2 - Understanding the ControlNet PLC-5
Backup System Components
3 - Installing and Configuring Your ControlNet
PLC-5 Backup System
System
5 - Monitoring and Troubleshooting Your
ControlNet PLC-5 Backup System
Terms and Conventions
application examples; items to consider
before designing the backup system
reference information on the ControlNet
backup module for users familiar with the
Allen-Bradley 1785-BCM systems
ControlNet Hot Backup terminology Glossary
E - Application Guidelines
F - Comparison to the 1785-BCM System
In this document, when we refer to the PLC-5s, we mean the
programmable controllers you are using in your ControlNet Hot
Backup system. We also refer to the PLC-5 as the "controller" or
"processor."
The screen captures and other examples that appear in this document
represent the current version of software at the time of publishing. A
later or earlier version of the same screen capture or example may be
slightly different but the purpose remains the same. Use the screen
captures and examples for reference only.
Publication 1785-UM024B-EN-P - January 2003
Preface 3
Related PLC-5 Publications
Related documentation for ControlNet and other PLC-5 programmable
controllers is available:
Publication Publication
Number
Enhanced PLC-5 Processor System Overview 1785-2.36
Enhanced and Ethernet PLC-5 Programmable Controllers User
Manual
ControlNet PLC-5 Programmable Controllers User Manual 1785-UM022
ControlNet PLC-5 Programmable Controllers Quick Start 1785-QS006
1785-PLC-5 Programmable Controllers Quick Reference 1785-7.1
1785-6.5.12
For more information about 1785 PLC-5 programmable controllers,
contact your local Rockwell Automation sales office or distributor.
To view or order these publications online, visit:
www.theautomationbookstore.com
Related ControlNet Publications
For detailed information about different aspects of planning and
installing your ControlNet network, see the following publications:
Publication Publication
Number
ControlNet Cable System Component List AG-2.2
ControlNet Coax Cable System Planning and Installation Manual 1786-6.2.1
ControlNet Network Access Cable Installation Instructions 1786-2.6
ControlNet System Overview 1786-SO001
ControlNet PLC-5 Hot Backup System User Manual 1785-6.5.24
ControlNet Fiber Planning Installation Guide CNET-IN001
Industrial Automation Wiring and Grounding Guidelines 1770-4.1
System Design for Control of Electrical Noise GMC-RM001
To view or order these publications online, visit:
www.theautomationbookstore.com
or contact your local Rockwell Automation sales office or distributor.
Publication 1785-UM024B-EN-P - January 2003
Preface 4
For more information on any of the software components of the
ControlNet PLC-5 backup system (e.g., RSLogix 5, RSLinx, and
RSNetWorx), refer to the software documentation and online help for
the individual software packages.
Publication 1785-UM024B-EN-P - January 2003
Summary of Changes
Summary of Changes
The information below summarizes the changes to the ControlNet
PLC-5 Hot Backup System User Manual.
New Features and Information
The following table highlights new features and information for the
Hot Backup system and its location in this manual.
For This New Information See Page(s)
Required Hardware, Software and Firmware Components Chapter 2 1 thru 4
Updated Installation and Configuration Procedures in
RSNetWorx
Advanced Configuration Options
User Program Control for Completion of Qualification
Configuring Optional Parameters in a ControlNet Hot
Backup System
Crossloading Data over Data Highway Plus
Requalification Option of Dual Primary Programmable
Controllers
Using I/O in Your ControlNet Hot Backup System Chapter 4 Chapter 4
Additional Hot Backup Major Fault Codes Chapter 5 5-2
Additional Invalid Backup State Codes 5-4
Troubleshooting with Output Ownership Verification 5-7
Chapter 3 1 thru 17
3-18
3-19
3-19
3-24
3-26
Additions to the ControlNet Backup and Configuration
Status Files
Specifications and Certifications Appendix A Appendix A
Considerations When Crossloading MG, BT or CT File Types Appendix C C-4
Appendix E E-4
Inhibiting ControlNet I/O Appendix E E-5
Sequential Process Application Considerations E-5
ControlNet Hot Backup Terminology Glossary Glossary
Index Index Index
1 Publication 1785-UM024B-EN-P - January 2003
5-8
Summary of Changes 2
Notes
Publication 1785-UM024B-EN-P - January 2003
Preface
Summary of Changes
Table of Contents
Manual Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-1
Who Should Use This Manual . . . . . . . . . . . . . . . . . . . . . . P-1
What This Manual Contains . . . . . . . . . . . . . . . . . . . . . . . . P-2
Terms and Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . P-2
Related PLC-5 Publications . . . . . . . . . . . . . . . . . . . . . . . . P-3
Related ControlNet Publications. . . . . . . . . . . . . . . . . . . . . P-3
New Features and Information. . . . . . . . . . . . . . . . . . . . . . S-1
Backup Concepts for the
ControlNet PLC-5 Hot Backup
System
Understanding the ControlNet
PLC-5 Hot Backup System
Components
Chapter 1
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Why Use a Backup System? . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Basic System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
How the Backup System Works. . . . . . . . . . . . . . . . . . . . . 1-2
Qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Equivalence Checking . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Bumpless Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Switchover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Chapter 2
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Hardware Components . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Software Components . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Firmware Components . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Summary of Required Hardware, Firmware and Software . . 2-4
ControlNet Backup Cartridge . . . . . . . . . . . . . . . . . . . . . . . 2-5
Installing and Configuring Your
ControlNet PLC-5 Backup
System
iii Publication 1785-UM024B-EN-P - January 2003
Chapter 3
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Installing the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Configuring Your Backup System . . . . . . . . . . . . . . . . . . . 3-2
Configuring With a Single Control Application . . . . . . . 3-3
Configuring With Differing Applications . . . . . . . . . . . . 3-11
Table of Contents iv
Advanced Configuration Options . . . . . . . . . . . . . . . . . . . . 3-18
Configuring Optional Parameters in a Backup System . . 3-19
Synchronous and Asynchronous Program Scanning. . . . 3-20
Equivalence Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21
Crossloading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
System Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23
Crossloading Over Data Highway Plus . . . . . . . . . . . . . 3-24
Requalification of Dual Primary Processors. . . . . . . . . . . . . 3-26
PLC-5 Editing Considerations . . . . . . . . . . . . . . . . . . . . . . . 3-26
Downloading Editing Changes . . . . . . . . . . . . . . . . . . . 3-27
Testing Data Table Edits. . . . . . . . . . . . . . . . . . . . . . . . 3-27
Using I/O in Your ControlNet Hot
Backup System
Monitoring and
Troubleshooting Your
ControlNet PLC-5 Hot Backup
System
Specifications
Chapter 4
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Considerations when Using I/O. . . . . . . . . . . . . . . . . . . . . 4-1
Redundant Connections . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Chapter 5
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
ControlNet PLC-5 Backup-Specific Major Fault Error Codes . 5-2
Using the 1785-CHBM Cartridge Status Indicators . . . . . . . . 5-3
Troubleshooting the Invalid Backup State . . . . . . . . . . . . . 5-4
Troubleshooting Qualification Major Faults . . . . . . . . . . . . 5-6
Troubleshooting Qualification Crossloads. . . . . . . . . . . . . . 5-7
Troubleshooting with Output Ownership Verification. . . . . 5-8
ControlNet Backup Configuration and Status File . . . . . . . . 5-8
Appendix A
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Backup States
Publication 1785-UM024B-EN-P - January 2003
Appendix B
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Invalid Backup State . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
No Control Backup State . . . . . . . . . . . . . . . . . . . . . . . B-3
Primary Backup State . . . . . . . . . . . . . . . . . . . . . . . . . . B-4
Lonely Primary Backup State . . . . . . . . . . . . . . . . . . . . B-5
Secondary Backup State . . . . . . . . . . . . . . . . . . . . . . . . B-5
Backup State Transitions . . . . . . . . . . . . . . . . . . . . . . . . . . B-6
Qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-6
Table of Contents v
Qualification: From No Control State to Primary State . . B-6
Qualification: From No Control State to Secondary State B-7
Reasons for Qualification Major Fault . . . . . . . . . . . . . B-14
Switchover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-14
Qualified Switchovers . . . . . . . . . . . . . . . . . . . . . . . . B-15
Unqualified Switchovers. . . . . . . . . . . . . . . . . . . . . . . B-16
Switchover Considerations . . . . . . . . . . . . . . . . . . . . . B-16
Data Table Crossloading
Program Synchronization
Appendix C
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Data Table Crossloading . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
On-Demand Data Table Crossloads . . . . . . . . . . . . . . . C-2
Optimizing On-Demand Crossloads . . . . . . . . . . . . . . . C-5
Triggering an On-Demand Data Table Crossload. . . . . . C-5
Qualification Crossloads. . . . . . . . . . . . . . . . . . . . . . . . C-6
Qualification Data Table Crossload . . . . . . . . . . . . . . . . C-7
Qualification State Data Table Crossload . . . . . . . . . . . . C-7
Data Table Crossload Time. . . . . . . . . . . . . . . . . . . . . . C-8
Data Table Crossload Data Latency. . . . . . . . . . . . . . . . C-8
Data Table Crossloading on ControlNet Channel . . . . . . C-9
Inhibiting Data Table Crossloads . . . . . . . . . . . . . . . . . C-9
Data Table Crossload Diagnostics . . . . . . . . . . . . . . . . . C-9
Data Table Crossloads Via Your Applications . . . . . . . C-10
Appendix D
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
Program Synchronization. . . . . . . . . . . . . . . . . . . . . . . . . . D-1
Determining Which Mode to Use . . . . . . . . . . . . . . . . . D-2
Using Synchronous Mode. . . . . . . . . . . . . . . . . . . . . . . D-2
Determining the Maximum Program Scan Time. . . . . . . D-2
Adjusted Maximum Program Scan Time . . . . . . . . . . . . D-3
Program Scan Overrun. . . . . . . . . . . . . . . . . . . . . . . . . D-3
Application Guidelines
Appendix E
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-1
Redundancy Considerations. . . . . . . . . . . . . . . . . . . . . . . . E-1
Switchover Considerations. . . . . . . . . . . . . . . . . . . . . . . . . E-2
Why Transfer Information? . . . . . . . . . . . . . . . . . . . . . . E-2
What Information Should Be Transferred? . . . . . . . . . . . E-3
When Should the Information Be Transferred? . . . . . . . E-4
How Often Should the Information Be Transferred?. . . . E-4
Performance Considerations . . . . . . . . . . . . . . . . . . . . . E-4
Inhibiting or Resetting ControlNet I/O . . . . . . . . . . . . . . . . E-5
Publication 1785-UM024B-EN-P - January 2003
Table of Contents vi
Sequential Process Application Considerations . . . . . . . . . . E-5
What Causes a PLC-5 to Get Into an Incorrect State. . . . E-6
How to Keep the Controllers in the Same Process State. E-7
When the Controllers are in Different States . . . . . . . . . E-8
Complete Qualification in the Same Process State . . . . . E-9
Comparison to the 1785-BCM
System
Glossary
Appendix F
Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-1
Comparison to the BCM System. . . . . . . . . . . . . . . . . . . . . F-1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-1
Publication 1785-UM024B-EN-P - January 2003
Chapter
Backup Concepts for the ControlNet PLC-5
Hot Backup System
1
Chapter Objectives
Why Use a Backup System?
This chapter describes why and how to use the ControlNet PLC-5
backup system and its basic system architecture.
The objective of any redundant system (i.e., backup system) is to
improve the amount of up-time of a machine or process by ensuring
consistent availability of that machine. This also reduces costs
associated with equipment failure. By using the ControlNet PLC-5 hot
backup system, you can help guard your application against
shutdowns caused by the programmable controller.
ATTENTION
!
The backup option is used where you must transfer the control of the
process to a secondary system without interrupting the
machine/process operation.
When using identical programs in both PLC-5
programmable controllers, using a backup system
does not necessarily protect you from faults
caused by programming errors or system timeouts.
Such errors or timeouts can also occur in the
secondary programmable controller. Be certain to
carefully check your programming, and to
thoroughly check redundant operations before
implementing the backup system.
To guard against system shutdown, a backup system must provide:
• equipment with exceptional reliability
• automatic fault isolation
• minimal disturbance of the process when switching from the
primary to the secondary system
1 Publication 1785-UM024B-EN-P - January 2003
1-2 Backup Concepts for the ControlNet PLC-5 Backup System
Basic System Architecture
How the Backup System Works
The following illustration describes the various components of the
basic ControlNet PLC-5 hot backup system:
TM
TM
In a ControlNet PLC-5 hot backup system, one PLC-5 programmable
controller, referred to as the primary programmable controller,
controls the operation of the ControlNet I/O. The other programmable
controller, referred to as secondary programmable controller, is set up
to take control of the ControlNet I/O in the event of a fault in the
primary programmable controller.
The ControlNet network is wired to both PLC-5 programmable
controllers, as well as to all ControlNet I/O in your system. Using
ControlNet, the programmable controllers communicate (or
“handshake”) with each other and exchange status information on
their operational states. If the primary programmable controller faults,
or is otherwise unable to continue control of the outputs, the
secondary programmable controller assumes control and becomes the
primary programmable controller.
Both PLC-5 programmable controllers are actively connected to the
ControlNet I/O, receive all input data sent by the I/O adapters, and
use that data as they execute their program scans. Output data is sent
via ControlNet from both programmable controllers. However, only
data from the primary programmable controller is used by the I/O
adapter(s).
With the ControlNet PLC-5 backup system there are several features to
consider that, though common to many backup systems, are uniquely
implemented in this particular system. Understanding these features
and their functions will help you design and implement your backup
applications.
Publication 1785-UM024B-EN-P - January 2003
Backup Concepts for the ControlNet PLC-5 Backup System 1-3
Qualification
When bringing the secondary programmable controller of a backup
system online, it is important to ensure that it is in a state that will
enable it to take over the control of the system in the event of a
primary failure. This process of verifying and conditioning the state of
the secondary programmable controller is known as qualification.
Switchover will not occur without a qualified secondary
programmable controller. Additionally, the system is not truly
considered a backup system until the secondary programmable
controller has successfully completed qualification.
The qualification phase includes several tests and verifications
between the primary and secondary programmable controllers, as
well as data table file crossloading. You can tailor these tests,
verifications, and data table file crossloads to ensure the level of
system integrity required for your application. These tests and
verifications may cover:
• configuration file validity and integrity checking
• application program and data file structure equivalence
checking
• I/O map connection comparison
• force table comparison
• status file comparison
Data table file crossloading from the primary to the secondary
programmable controller may include the transfer of integer values,
floating point values, timers, counters, PID values, and others you
select.
Publication 1785-UM024B-EN-P - January 2003
1-4 Backup Concepts for the ControlNet PLC-5 Backup System
Equivalence Checking
Backup systems are traditionally designed in a way such that both the
primary and secondary programmable controllers are programmed
with identical applications. This allows for the controlled process to
continue with normal production operation in the event of a primary
programmable controller failure. Equivalence checks ensure that the
primary and secondary programmable controllers have identical
ladder programs, data file structures, I/O map connection, etc. You, as
the designer of the backup system, require the ability to enforce
equivalence checks between the primary and secondary
programmable controllers during the qualification process, and
periodically during normal production operation.
In some cases, you may want the secondary programmable controller
to have a completely different application than the primary
programmable controller (e.g., “safe shutdown,” limited production,
clean and wash, etc.). In that case, equivalence checking may not be
required. With the ControlNet PLC-5 hot backup system, you can
enable or disable equivalence checking as required by your
application. You must have a thorough understanding of your
application in order to make this determination.
Bumpless Transfer
Ideally, when a programmable controller switchover takes place in the
backup system, there should be no adverse effect on system
operation, and the controlled process should continue to run as
though it were still being controlled by the original primary
programmable controller. This is generally referred to as a bumpless
transfer of control.
Bumpless transfer is not required for many backup applications, but it
is highly desirable. Divergence in program scanning, I/O tables, data
tables, and long switchover times can all cause bumps when
transferring control from a primary to a secondary programmable
controller. The ControlNet PLC-5 hot backup system allows you to
choose synchronous program scan operation, as well as on-demand
crossloading of data table files you select. These options can greatly
reduce the possibility of bumps during a programmable controller
switchover.
Publication 1785-UM024B-EN-P - January 2003
Backup Concepts for the ControlNet PLC-5 Backup System 1-5
Switchover
Switchover is what occurs when the secondary programmable
controller assumes control of the process, thus becoming the primary
programmable controller. Several conditions can cause this to happen:
• critical failures in the primary programmable controller (e.g.,
hardware faults)
• internal conditions within the primary programmable controller
(e.g., a major fault), causing it to relinquish control of the
process to the secondary programmable controller
• external conditions recognized by the secondary programmable
controller (e.g., loss of communications with the primary
programmable controller), causing it to assume control of the
process
• a manual switchover (i.e., a forced switchover, where you cause
the secondary programmable controller to become primary, and
vice versa; you may choose to do this when testing your system
for backup performance and integrity, or as part of a system
maintenance program).
The ideal switchover time from the primary programmable controller
to the secondary programmable controller would be instantaneous.
The ControlNet PLC-5 hot backup system typically provides a
switchover time of 30-50 ms. This time is adequate to avoid a bump in
most systems, but you should determine the maximum allowable
switchover time for your applications.
Publication 1785-UM024B-EN-P - January 2003
1-6 Backup Concepts for the ControlNet PLC-5 Backup System
Notes
Publication 1785-UM024B-EN-P - January 2003
Chapter
Understanding the ControlNet PLC-5 Hot
Backup System Components
2
Chapter Objectives
This chapter describes the components that make up the ControlNet
PLC-5 hot backup system.
Hardware Components
• two PLC-5 ControlNet programmable controllers (either
1785-L40C15 or 1785-L80C15, Series F, Revision A or later)
Each programmable controller must be in a separate 1771
chassis, and each chassis must have its own power supply.
Various chassis and power supplies are available; choose them
based upon standard 1771 and 1785 selection and installation
criteria.
TIP
Though we do not recommend it, it is possible for
you to use a mixed set of programmable controllers
as a backup pair (e.g., one PLC-5/40 and one
PLC-5/80).
• two 1785-CHBM/A ControlNet backup cartridges (one for each
PLC-5 programmable controller)
• two 1771 chassis (one for each PLC-5 programmable controller)
• two 1771 power supplies (one for each chassis)
You can elect to use redundant power supplies within a chassis
if you wish. We do not recommend the use of I/O within the
chassis, since provisions for backing up the local I/O are not
provided.
• one or more ControlNet I/O adapters
1 Publication 1785-UM024B-EN-P - January 2003
2-2 Understanding the ControlNet PLC-5 Hot Backup System Components
• ControlNet network cables, taps, and terminators for making
connections between the PLC-5 programmable controllers and
the I/O adapters
• a PC with a 1784-KTCX15 card, or a laptop computer with a
1784-PCC card
• other ControlNet devices, including HMI (optional)
Software Components
The basic ControlNet PLC-5 backup system includes the following
software components:
• RSLogix 5 programming software (Release 3.21 or later)
• RSNetWorx for ControlNet software (Release 1.80 or later)
• RSLinx communication software (Release 2.00.97.30 or later)
Firmware Components
IMPORTANT
If your version of RSNetWorx does not recognize a newer ControlNet
PLC-5, you may need to update your RSNetworx software or the
Electronic Data Sheet (EDS) for the programmable controller. To
update your EDS file, use the Hot Backup CD that was shipped with
your ControlNet PLC-5 programmable controller. If you don’t have the
CD, contact Rockwell Automation Technical Support at 440-646-5800
to update your EDS file.
This Series, Revision of Firmware: Is only compatible with:
Series F/Revisions C, C.1 and C.2 Series F/Revisions C, C.1 and C.2
Series F/Revisions B and B.1 Series F/Revisions B and B.1
Series F/Revisions A, A.1, A.2 and A.3 Series F/Revisions A, A.1, A.2 and A.3
ControlNet PLC-5 programmable controllers in a
backup system must have compatible firmware
revisions. This insures proper operation if a
switchover occurs. Subrevision releases (such as A.1,
A.2 and so on) are compatible with other subrevision
releases of the same series and revision. Refer to the
table below to determine compatibility.
Publication 1785-UM024B-EN-P - January 2003
Additionally, be sure that all spare ControlNet PLC-5 hot backup
processors contain compatible firmware.
Understanding the ControlNet PLC-5 Hot Backup System Components 2-3
Compatibility Considerations
If the firmware series or revision do not match between the two
programmable controllers in a backup system, one or both
programmable controllers will detect an incompatibility and indicate a
Major Fault code 238. If the fault is cleared without correcting the
compatibility issue, the fault will continue to occur. However, the fault
will not occur in a programmable controller if it is in Run mode and is
controlling outputs.
IMPORTANT
The firmware revision in programmable controllers
in an operational backup system cannot be revised
during operation. The backup system and the
application must be powered down to revise the
firmware in one or both programmable controllers.
Firmware Update Considerations
You can change the firmware in a programmable controller for two
reasons. You can either:
• upgrade an older version of firmware to a new version, or
• backflash a newer version of firmware to an older version
For example, in an operational backup system, both programmable
controller’s firmware are at Series F, Revision A. If one programmable
controller fails and needs replacing, it must be replaced with an
identical series and firmware revision (Series F/Revision A). If a spare
part programmable controller is available, but it contains Series F/
Revision C firmware, it must be backflashed to Series F/Revision A.3.
IMPORTANT
PLC-5 programmable controllers Series F/Revision C
contain new flash devices and do not allow
Revisions A, A.1 A.2 and B to be backflashed into
them. They can only be backflashed with Revisions
A.3 and B.1 firmware, respectively.
Likewise, if you want to upgrade firmware in a backup system from
Series F/Revision A to Series F/Revision C, you would perform a flash
upgrade to both programmable controllers to ensure compatibility in
the backup system.
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2-4 Understanding the ControlNet PLC-5 Hot Backup System Components
Summary of Required
The following table summarizes hardware, firmware and software
requirements. Additionally, the table describes major enhancements
Hardware, Firmware and
and in what revision of firmware they were made.
Software
Hardware
Required PLC-5 Programmable
Controllers:
1785-L40C15 or -L80C15, Series F 1794-ACN15 or -ACNR15
Firmware for:
PLC-5 Programmable Controllers FLEX I/O Adapter 1771 Adapter SLC Adapter
Series/Revision firmware must match for
ControlNet Hot Backup
Series F, Revision A.1 minimum for
ControlNet Hot Backup
Series F, Revision B firmware added
DataHighway Plus cross loading, fault code
for incompatible firmware revisions,
requalification of dual primary PLC-5
programmable controllers and user program
control for completion of qualification
enhancements
If you are using a FLEX
I/O adapter:
Series B, Revision A or later
Series C, Revisions E and F
added noisy network
tolerance.
Series D, Revision A is
required for IB32P module
support
If you are using a 1771
adapter:
1771-ACNR15 Series B,
Revision E or later
Series B, Revision H added
scheduled data update
latency enhancement
Series B, Revision J is
adding ControlNet Hot
Backup capability and
performance enhancements
to the 1771-ACN15 adapter
If you are using an SLC
adapter:
1747-ACN, -ACNR Series A,
Revision B or later
Series F, Revision C added SLC I/O, multicast
outputs, additional ControlNet I/O status bits
and expanded ControlNet I/O instruction
capability enhancements
Series F, Revision C.2 added noisy network
tolerance and performance enhancements
Software for:
PLC-5 Programmable Controllers FLEX I/O Adapter 1771 Adapter SLC Adapter
Windows 95 or Windows NT operating
system
RSLogix 5 ver. 3.21 or later RSLogix 5 ver. 3.21 or later RSLogix 5 ver. 3.21 or later RSLogix 5 ver. 5.0
RSNetWorx for ControlNet ver. 1.80 or later RSNetWorx for ControlNet
Windows 98 or Windows
NT operating system
ver. 1.80 or later
Windows 98 or Windows
NT operating system
RSNetWorx for ControlNet
ver. 1.80 or later
Windows 98 or Windows
NT operating system
RSNetWorx for ControlNet
3.0
Publication 1785-UM024B-EN-P - January 2003
Understanding the ControlNet PLC-5 Hot Backup System Components 2-5
ControlNet Backup Cartridge
Each ControlNet PLC-5 programmable controller requires a
1785-CHBM/A ControlNet backup cartridge, inserted into the PLC-5
EEPROM memory cartridge slot, to enable backup functionality.
The ControlNet backup cartridge contains EEPROM memory cartridge
functionality (i.e., the cartridge can also be used as a standard PLC-5
EEPROM memory storage cartridge for the PLC-5 programmable
controller, with up to 100K of memory).
IMPORTANT
The 1785-CHBM ControlNet backup cartridge cannot
be used with non-backup PLC-5 programmable
controllers.
Publication 1785-UM024B-EN-P - January 2003
2-6 Understanding the ControlNet PLC-5 Hot Backup System Components
Notes
Publication 1785-UM024B-EN-P - January 2003
Chapter
Installing and Configuring Your ControlNet
PLC-5 Backup System
3
Chapter Objectives
Installing the Hardware
This chapter outlines the steps you must perform to install the backup
system components, and to subsequently configure them to create a
functioning backup system.
Before you begin, be sure that you have all of the required hardware
components, as listed in Chapter 2.
Follow these steps to install the required hardware for your backup
system.
1. Set the ControlNet node address number for each of the PLC-5
processors.
IMPORTANT
The node addresses must be consecutive, with the
lower number being odd. For example, a valid node
address pair is 1 and 2. You set the ControlNet node
address via the rotary switches on the top of each
processor. You may need to change the ControlNet
node address of other devices so that you have two
consecutive addresses available on your ControlNet
network.
2. Install each PLC-5 processor into a separate 1771 chassis.
3. Make certain that power is removed from each PLC-5.
4. Insert the 1785-CHBM ControlNet backup cartridge into the
EEPROM slot of each PLC-5 processor.
IMPORTANT
5. Install a power supply for each chassis, and connect to ac
power.
1 Publication 1785-UM024B-EN-P - January 2003
If the ControlNet backup cartridge is not inserted
into the PLC-5 processor, that processor will operate
as a normal, standalone processor, and will not
exhibit any of the necessary backup functions.
3-2 Installing and Configuring Your ControlNet PLC-5 Backup System
6. Wire the ControlNet network to the PLC-5 processors and to the
ControlNet I/O adapters being used for the backup system.
IMPORTANT
The network cabling may consist of single or redundant
channels.
IMPORTANT
Basic installation is now complete.
7. Set the keyswitch to Program mode on each processor and
apply power to the processors.
Make certain that both ControlNet Hot Backup
PLC-5s and the Hot Backup I/O are on the same
ControlNet network. Bridging to another ControlNet
network is not allowed.
In non-redundant media applications, place your two
PLC-5 processors as the 2 nodes closest to a
terminator on a ControlNet segment. This eliminates
the possibility for a malfunctioning cable between
the processors to allow each processor to control a
subset of the I/O.
Configuring Your Backup System
Before you begin, make sure that you have installed RSLinx, RSLogix5,
and RSNetWorx for ControlNet software. For assistance with installing
any of these packages, refer to their respective installation
documentation.
There are two basic configuration paths. Select the appropriate path
based upon the type of backup system you are creating.
• If you are creating a backup system with identical (or nearly
identical) control applications in the primary and secondary
controllers, complete the steps in the section of this chapter
entitled “Configuring With a Single Control Application.”
• If you are creating a backup system where the secondary
controller is running a different application than the primary,
complete the steps in the section of this chapter entitled
“Configuring With Different Applications.”
Publication 1785-UM024B-EN-P - January 2003
Installing and Configuring Your ControlNet PLC-5 Backup System 3-3
Configuring With a Single Control Application
This section assumes that you have already developed your control
application and have loaded it onto a single ControlNet PLC-5
processor (i.e., a non-backup system). Throughout this section, we
will refer to this processor as the first processor. Furthermore, we
assume that you have a second processor installed, powered on, and
in its default state. Both processors must be in Program mode and
must be physically connected to your ControlNet network.
To create and configure your backup system under these
circumstances, complete the following steps:
1. Reconfigure ControlNet I/O on the first PLC-5.
2. Configure handshaking messages between both PLC-5s.
3. Configure ControlNet I/O on the second PLC-5.
4. Save the ControlNet configuration.
5. Configure the hot backup parameters on the first PLC-5and save
the project.
6. Create and download the project for the second PLC-5 and save
the project.
Reconfigure ControlNet I/O on the First PLC-5
Reconfigure all ControlNet I/O adapters and modules that will be in
your ControlNet PLC-5 backup system by changing their ControlNet
connection from Exclusive Owner (default) to Redundant Owner.
1. Launch RSNetWorx for ControlNet.
2. Check the Edits Enabled checkbox on the toolbar.
3. Right click on the first PLC-5 processor (the odd-numbered
node) and choose Scanlist Configuration.
Publication 1785-UM024B-EN-P - January 2003
3-4 Installing and Configuring Your ControlNet PLC-5 Backup System
The Scanlist Configuration screen appears.
4. For each entry under the Connection Name column, double
click on Exclusive Owner, choose Redundant Owner from
the pull-down menu, and press Enter.
Configure Handshaking Messages With RSNetWorx
Within your backup system, you must use RSNetWorx to set up the
send and receive scheduled messages that allow handshaking to occur
between the two ControlNet PLC-5s that comprise your backup
system.
For each of the PLC-5s comprising a backup system, you must create
two scheduled peer-to-peer messages: one Produce Buffer ID (send)
and one Consume Buffer ID (receive). These messages must be
exactly five words in length
From the Scanlist Configuration screen for the first PLC-5, follow
these steps:
1. Right click on the even-numbered node (Node 2 in this
example) and choose Insert Connection.
Publication 1785-UM024B-EN-P - January 2003
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