Rockwell Automation 1756-SYNCH User Manual
ControlLogix
SynchLink Module
1756-SYNCH
User Manual
Important User Information
Solid state equipment has operational characteristics differing from those of
electromechanical equipment. Safety Guidelines for the Application,
Installation and Maintenance of Solid State Controls (Publication SGI-1.1
available from your local Rockwell Automation sales office or online at
http://www.ab.com/manuals/gi) 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 Rockwell Automation, Inc. 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, Rockwell Automation, Inc. cannot assume
responsibility or liability for actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. 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 Rockwell Automation, Inc. is prohibited.
Throughout this manual, when necessary we use notes to make you aware of
safety considerations.
WARNING
IMPORTANT
ATTENTION
SHOCK HAZARD
BURN HAZARD
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.
Identifies information that is critical for successful
application and understanding of the product.
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 a hazard
• recognize the consequence
Labels may be located on or inside the equipment (e.g.,
drive or motor) to alert people that dangerous voltage may
be present.
Labels may be located on or inside the equipment (e.g.,
drive or motor) to alert people that surfaces may be
dangerous temperatures.
Summary of Changes
Introduction
New and Revised Information
This release of this publication contains updated information. Change
bars, as shown in the right margin of this page, designate locations in
the publication that contain changed information.
Table Summary of Changes.1 lists the new and revised information included in
this publication.
Table Summary of Changes.1
In this section: This information was changed or added:
Chapter 2 The brief description of Configuring Time Mastership
Functionality was changed to reflect changes on the module.
For more information, see page 2-5.
Chapter 3 For 1756-SYNCH modules using firmware revision 2.18 or
greater, the module can now use its last configuration when
its connection to the owner-controller closes.
For more information, see page 3-5.
The electronic keying description has been revised.
For more information, see page 3-11.
The Multiplier description has been revised to describe how
the module may truncate values beyond the decimal point.
For more information, see page 3-17.
The CST and SynchLink Mastership description has
changed significantly.
For more information, see page 3-18.
Chapter 5 New configuration screens are included to reflect the
1756-SYNCH module’s new role in Coordinated System Time
(CST) Mastership.
For more information, see page 5-7.
Chapter 6 The behavior of the 1756-SYNCH module’s status indicators
has changed slightly.
For more information, see page 6-2.
Appendix A Updated specifications are available.
Appendix E A full description of the 1756-SYNCH module’s newly
incorporated Configuration Data Tags is available.
For more information, see page E-3.
Other changes have been made throughout this manual and, although
not significant enough to warrant mention in the table above, they are
marked by change bars.
1 Publication 1756-UM521C-EN-P - July 2004
Summary of Changes 2
Publication 1756-UM521C-EN-P - July 2004
Preface
About This Preface
This preface describes how to use this manual. The following table
describes what this preface contains and its location.
Table Preface.1
For information about: See page:
Who Should Use This Manual Preface-1
Purpose of This Manual Preface-1
Using the Latest Module Firmware Preface-2
What This Manual Contains Preface-4
Related Products and Documentation Preface-5
Who Should Use This Manual
Purpose of This Manual
You must be able to program and operate an Allen-Bradley
ControlLogix™ controller and ControlLogix I/O modules to efficiently
use your SynchLink™ module.
We assume that you know how to do this in this manual. If you do
not, refer to Related Documentation, before you attempt to use this module.
IMPORTANT
This manual describes how to install, configure, and troubleshoot
your ControlLogix SynchLink module.
SynchLink should be used in conjunction with a
standard control network, such as ControlNet or
Ethernet. A standard network is used for general
control interlocking and transfer of diagnostic data
across the system.
SynchLink does not function as a standard control
network (e.g. it broadcasts data in a unidirectional
manner).
1 Publication 1756-UM521C-EN-P - July 2004
Preface 2
Using the Latest Module Firmware
This manual describes changes to the 1756-SYNCH module when the
module uses firmware revision 2.18. Some of the features described in
this publication may not be available on modules using previous
firmware revisions.
We recommend that you upgrade your 1756-SYNCH module to
firmware revision 2.18 or greater when possible to use fully the
module’s functionality.
FLASH Upgrade the Module’s Firmware Revision
To update a 1756-SYNCH module’s firmware of a controller, first
install a firmware upgrade kit.
• An upgrade kit ships on a supplemental CD along with RSLogix
5000 software.
• To download an upgrade kit:
1. Go to www.ab.com.
2. Choose Product Support.
3. Choose Firmware Updates.
Update the Module
1. Connect the 1756-SYNCH module to the same network as
your workstation.
2. Start ControlFLASH software.
3. Choose N
4. Select the 1756-SYNCH catalog number and choose N
ext >.
ext >.
Publication 1756-UM521C-EN-P - July 2004
5. Expand the network until you see the module. If the required
network is not shown, first configure a driver for the network in
RSLinx software.
6. Select the controller and choose OK.
7. Select the revision level to which you want to update the
1756-SYNCH module and choose N
ext >.
Preface 3
IMPORTANT
If the Revision list is empty, download a new
upgrade kit. Some older upgrade kits do not work
with new modules.
8. To start the update of the module, choose Finish and then Ye s.
After the module is updated, the status box displays
Update complete.
9. Choose OK.
10. To close ControlFLASH software, choose Cancel and then Yes
Publication 1756-UM521C-EN-P - July 2004
Preface 4
What This Manual Contains
This user manual contains the following sections:
Table Preface.2
Section: Title: Description:
Chapter 1 What is the 1756-SYNCH
module?
Chapter 2 Time Synchronization in the
ControlLogix System
Chapter 3 SynchLink Module Features Listing and description of the
Chapter 4 Installing the SynchLink
Module
Chapter 5 Configuring the SynchLink
Module
Chapter 6 Troubleshooting the
SynchLink Module
Appendix A Specifications Listing of the ControlLogix SynchLink
Overview of the ControlLogix SynchLink
module
Description of how the ControlLogix
SynchLink module fits in the
ControlLogix system
ControlLogix SynchLink module’s
features
Description of how to install the
ControlLogix SynchLink module
Description of how to use RSLogix 5000
to configure the ControlLogix
SynchLink module
Description of how to use module
indicators and RSLogix 5000 to
diagnose and correct problems with the
ControlLogix SynchLink module
module’s specifications
Appendix B Configuring the Star
Configuration
Appendix C Configuring the Daisy Chain
Configuration
Appendix D Configuring the Ring
Configuration
Appendix E Software Configuration Tags Description of the module-defined data
Description of how to set up a star
configuration with the ControlLogix
SynchLink module
Description of how to set up a daisy
chain configuration with the
ControlLogix SynchLink module
Description of how to set up a ring
configuration with the ControlLogix
SynchLink module
types and tags created in RSLogix 5000
for the ControlLogix SynchLink module
Publication 1756-UM521C-EN-P - July 2004
Preface 5
Related Products and Documentation
The following table lists related ControlLogix products and
documentation:
Table Preface.3 Related Documentation
Catalog
number:
1756-SYNCH ControlLogix SynchLink Module Installation
1756-A4, -A7,
-A10, -A13, -A17
1756-PA72,
-PB72
1756-PA75,
-PB75
1756-PA75R,
-PB75R
1756-Series ControlLogix Module Installation Instructions
1756-Series ControlLogix System User Manual 1756-UM001
Multiple numbers SynchLink Design Guide 1756-TD008
1751-SLBA SynchLink Base Block Installation Instructions 1751-IN001
Document title: Publication
number:
1756-IN575
Instructions
ControlLogix Chassis Installation Instructions 1756-IN080
ControlLogix Power Supply Installation Instructions 1756-5.67
ControlLogix Power Supply Installation Instructions 1756-5.78
ControlLogix Redundant Power Supply Installation
Instructions
(Each module has separate installation document.)
1756-IN573
Multiple
1756-IN
numbers
1751-SL4SP SynchLink 4-port Splitter Block Installation
Instructions
1751-SLBP SynchLink Bypass Switch Block Installation
Instructions
1756-DM ControlLogix Drive Module Installation Instructions 1756-IN577
1756-DM ControlLogix Drive Module User Manual 1756-UM522
PowerFlex 700S User Manual 20D-UM001
1756-IB16ISOE,
-IH16ISOE
ControlLogix Sequence of Events Module User
Manual
1751-IN002
1751-IN003
1756-UM528
For more information on these products, contact your local Rockwell
Automation distributor or sales office. The documentation listed in
Table Preface.3 is available at:
• http://www.ab.com/manuals
• http://www.theautomationbookstore.com
Publication 1756-UM521C-EN-P - July 2004
Preface 6
Notes:
Publication 1756-UM521C-EN-P - July 2004
What is the 1756-SYNCH module?
Time Synchronization in the
ControlLogix System
Table of Contents
Chapter 1
What is the ControlLogix SynchLink Module?. . . . . . . . . . . . . . . . . . 1-1
What Data Does the SynchLink Module Transfer?. . . . . . . . . . . 1-1
Why Synchronize Time Between Chassis? . . . . . . . . . . . . . . . . . . 1-2
What Are Some of the Features Available On the
ControlLogix SynchLink Module? . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Connecting a SynchLink Module to a SynchLink System . . . . . . . . . 1-3
Physical Features of the ControlLogix SynchLink Module . . . . . 1-4
Using Module Identification and Status Information. . . . . . . . . . . . . 1-5
Preventing Electrostatic Discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Removal and Insertion Under Power . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Chapter 2
Using the Coordinated System Time (CST) . . . . . . . . . . . . . . . . . . . . 2-2
Time Synchronization in a Distributed Control System . . . . . . . . . . 2-2
Time Synchronization in the SynchLink System . . . . . . . . . . . . . . . . 2-2
SynchLink Node Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
How Do the CST Clock and SynchLink Node Clock
Work Together? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Configuring Time Mastership Functionality. . . . . . . . . . . . . . . . . . . . 2-5
What are the SynchLink Configurations? . . . . . . . . . . . . . . . . . . . . . . 2-6
Star Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Daisy Chain Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Ring Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Cable Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Chapter 3
SynchLink Module Features
1 Publication 1756-UM521C-EN-P - July 2004
Module Features That Cannot Be Configured . . . . . . . . . . . . . . . . . . 3-2
Removal and Insertion Under Power (RIUP) . . . . . . . . . . . . . . . 3-2
Module Fault Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Full RSLogix 5000 Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Status Indicator (LED) Information. . . . . . . . . . . . . . . . . . . . . . . 3-4
Class I Division 2 Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Agency Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Use Last Configuration When Connection Closes . . . . . . . . . . . 3-5
Module Features That Can Be Configured. . . . . . . . . . . . . . . . . . . . . 3-5
Communications Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Electronic Keying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
Requested Packet Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
SynchLink Transmitted Axes . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Transmitted Direct Words . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
CST and SynchLink Mastership . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . 3-20
Table of Contents 2
Installing the SynchLink Module
Configuring the SynchLink Module
Chapter 4
Noting the Power Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Installing the Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Connecting the Fiber Optic Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Removing the Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Chapter 5
RSLogix 5000 Configuration Software . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Overview of the Configuration Process . . . . . . . . . . . . . . . . . . . . . . . 5-2
Choose a SynchLink Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Star Configuration.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Daisy Chain Configuration.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Ring Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Creating a New Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Downloading New Configuration Data . . . . . . . . . . . . . . . . . . . . . . . 5-8
Changing Configuration After Module Operation Has Begun . . . . . 5-9
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Troubleshooting the
SynchLink Module
Specifications
Chapter 6
Using the Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Using RSLogix 5000 to Troubleshoot the Module. . . . . . . . . . . . . . . 6-3
Determining Fault Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Using Diagnostic Counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Message Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Enter Message Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Chapter Summary and What’s Next . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Appendix A
Publication 1756-UM521C-EN-P - July 2004
Configuring the Star Configuration
Configuring the Daisy Chain
Configuration
Configuring the Ring Configuration
Software Configuration Tags
Glossary
Index
Table of Contents 3
Appendix B
Using Remote Axis Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Configure Time Master Chassis - Master Node. . . . . . . . . . . . . . B-2
Configure Time Slave Chassis - End Node . . . . . . . . . . . . . . . . . B-8
Configure Time Slave Chassis - End Node . . . . . . . . . . . . . . . . B-13
Appendix C
Configure Time Master Chassis - Master Node. . . . . . . . . . . . . . C-2
Configure Time Slave Chassis - Center Node . . . . . . . . . . . . . . . C-7
Configure Time Slave Chassis - End Node . . . . . . . . . . . . . . . . C-12
Appendix D
Configure Time Master Chassis - Master Node. . . . . . . . . . . . . D-2
Configure Time Slave Chassis - Center Node . . . . . . . . . . . . . . D-7
Configure Time Slave Chassis - End Node . . . . . . . . . . . . . . . D-12
Appendix E
Accessing the Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2
Configuration Data Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-3
Input Data Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-3
Output Data Tags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-5
Rockwell Automation Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Installation Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
New Product Satisfaction Return . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
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Table of Contents 4
Publication 1756-UM521C-EN-P - July 2004
Chapter
1
What is the 1756-SYNCH module?
This chapter describes the ControlLogix SynchLink module. It also describes
what you must know and do before using the SynchLink module.
Table 1.1
For information on: See page:
What is the ControlLogix SynchLink Module? 1-1
Connecting a SynchLink Module to a SynchLink System 1-3
Using Module Identification and Status Information 1-5
Preventing Electrostatic Discharge 1-6
Removal and Insertion Under Power 1-6
What is the ControlLogix SynchLink Module?
A ControlLogix SynchLink module, through the use of fiber optic
communication technology, allows you to implement:
• time synchronization
• distributed motion control
• coordinated drive control
based on the ControlLogix and PowerFlex 700S platforms. In distributed
control system, the SynchLink module broadcasts reference data and
synchronizes time from a single ControlLogix chassis to multiple other chassis
at a high speed.
What Data Does the SynchLink Module Transfer?
The SynchLink module transfers multiple types of reference data between
chassis, including:
• Produced axis data for chassis to chassis remote axis control
• High speed drive reference data for chassis to drive control
• General control information that requires transfer at a high speed and in
a synchronized manner
1 Publication 1756-UM521C-EN-P - July 2004
1-2 What is the 1756-SYNCH module?
Why Synchronize Time Between Chassis?
In synchronizing time between chassis, the SynchLink module allows you to:
• share motion data from chassis to chassis because a consistent time
reference is available among chassis for interpolation of velocity and
position data.
• timestamp I/O in multiple chassis and have a common time reference
with which to compare the timestamps.
For more information on how the SynchLink module impacts the time
references between ControlLogix chassis, see Chapter 2, Time
Synchronization in the ControlLogix System.
What Are Some of the Features Available On the ControlLogix
SynchLink Module?
The following are some of the features available on the ControlLogix
SynchLink module:
• Support of multiple SynchLink system configurations - Star, daisy chain
and ring
For more information on these functions, see Chapter 2, Time
Synchronization in the ControlLogix System.
For more information on how to configure the module with RSLogix
5000, see Chapter 5, Configuring the SynchLink Module.
• Removal and insertion under power (RIUP) - This system feature allows
you to remove and insert the module while power is applied. For more
information on RIUP, see page 1-6.
• Communication of remote axis data in a timely and
deterministic manner
• Communication of direct and buffered data
• Class I Division 2, UL, CSA, and CE Agency Certification
Publication 1756-UM521C-EN-P - July 2004
What is the 1756-SYNCH module? 1-3
Connecting a SynchLink Module to a SynchLink System
ControlLogix SynchLink modules mount in a ControlLogix chassis and
connects to other SynchLink node through a fiber optic cable system.
For more information on the available fiber optic cables, see Table 1.2.
Table 1.2 Fiber Optic Cables Available with the 1756-SYNCH Module
Catalog number: Cable length Cables per box:
1403-CF001 1m (3.28ft) 2
1403-CF003 3m (9.84ft)
1403-CF005 5m (16.4ft)
1403-CF010 10m (32.8ft) 1
1403-CF020 20m (65.6ft)
1403-CF050 50m (164ft)
1403-CF100 100m (328ft)
1403-CF250 250m (820ft)
When you install the SynchLink module in a Star Configuration, you need to
use hubs as well as fiber optic cables. A hub is a combination of one base block
with up to four splitter blocks. A bypass switch block is also available for use in
the daisy chain configuration. For more information on the Star
Configuration, see 2-6.
For more information the hub components available for use with the
SynchLink module, see Table 1.3
Table 1.3 Hub Components Available with the 1756-SYNCH Module
Catalog Number: Hub Type:
1751-SLBA SynchLink Fiber Base Block
1751-SL4SP SynchLink Fiber 4-Port Splitter Block
1751-SLBP SynchLink Fiber Bypass Switch Block
For more information on SynchLink fiber optic cable systems, see The
SynchLink Design Guide, publication 1756-TD008.
Publication 1756-UM521C-EN-P - July 2004
1-4 What is the 1756-SYNCH module?
Physical Features of the ControlLogix SynchLink Module
Figure 1.1
Module side view Module front view
Backplane
Connector- Interface
to the ControlLogix
system backplane
Tr an sm it
Fiber Port
Receive
Fiber Port
LINK
COMM
LINK
SYNC
OK
Status
Indicators
42744
Publication 1756-UM521C-EN-P - July 2004
Table 1.4 lists descriptions of the physical features shown in Figure 1.1.
Table 1.4
Physical Feature: Description:
Backplane connector The backplane connector connects the
module to the ControlLogix chassis
backplane.
Status indicators The status indicators display the module’s
communications and SynchLink system
status.
Transmit fiber port The transmit fiber port allows connection
(via fiber optic cables) to other SynchLink
modules so the module can send data.
Receive fiber port The receive fiber port allows connection (via
fiber optic cables) to other SynchLink
modules so the module can receive data.
What is the 1756-SYNCH module? 1-5
Using Module Identification and Status Information
Each ControlLogix SynchLink module maintains specific identification
information that separates it from all other modules. This information assists
you in tracking all the components of your system.
For example, you can track module identification information to be aware of
exactly what modules are located in any ControlLogix rack at any time. While
retrieving module identity, you can also retrieve the module’s status.
Each module maintains the following information:
Table 1.5 Module Identification and Status Information
Module Identification: Description:
Product Type Module’s product type, such as Digital I/O or Analog I/O
module
Product Code Module’s catalog number
Major Revision Module’s major revision number
Minor Revision Module’s minor revision number
Status Module’s status. Returns the following information:
• Controller ownership (if any)
• Whether module has been configured
• Device Specific Status, such as:
– Self-Test
– Flash update in progress
– Communications fault
– Not owned (outputs in program mode)
– Internal fault (need flash update)
– Run mode
• Minor recoverable fault
• Minor unrecoverable fault
• Major recoverable fault
• Major unrecoverable fault
Vendor ID Module manufacturer vendor, for example Allen-Bradley
Serial Number Module serial number
Length of ASCII Text String Number of characters in module’s text string
ASCII Text String Module name
IMPORTANT
To retrieve this information, you can use the WHO service
in RSLinx. For more information on how to retrieve
module identification information, see the RSLinx online
help.
Publication 1756-UM521C-EN-P - July 2004
1-6 What is the 1756-SYNCH module?
Preventing Electrostatic Discharge
Removal and Insertion Under Power
This module is sensitive to electrostatic discharge.
ATTENTION
These modules are designed to be installed or removed while chassis power is
applied.
WARNING
This equipment is sensitive to electrostatic discharge, which
can cause internal damage and affect normal operation.
Follow these guidelines when you handle this equipment:
• Touch a grounded object to discharge potential static.
• Wear an approved grounding wriststrap.
• Do not touch connectors or pins on component
boards.
• Do not touch circuit components inside the equipment.
• If available, use a static-safe workstation.
• When not in use, store the equipment in appropriate
static-safe packaging.
When you insert or remove the module while backplane
power is on, an electrical arc can occur. This could cause an
explosion in hazardous location installations. Be sure that
power is removed or the area is nonhazardous before
proceeding.
Chapter Summary and What’s Next
Repeated electrical arcing causes excessive wear to contacts on both the
module and its mating connector. Worn contacts may create electrical
resistance that can affect module operation.
In this chapter, you read about the ControlLogix SynchLink module. For
information about Time Synchronization in the ControlLogix System, see
Chapter 2.
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Chapter
Time Synchronization in the
ControlLogix System
This chapter describes how the ControlLogix SynchLink module fits in
the ControlLogix system.
Table 2.1
For information on: See page:
Using the Coordinated System Time (CST) 2-2
Time Synchronization in a Distributed Control System 2-2
Time Synchronization in the SynchLink System 2-2
How Do the CST Clock and SynchLink Node Clock Work Together? 2-5
2
What are the SynchLink Configurations? 2-6
Before you can fully understand how the SynchLink module can be
used in a distributed ControlLogix system, you should understand
how a ControlLogix application works without SynchLink. See the
ControlLogix System User Manual, publication 1756-UM001 for a
detailed description of the ControlLogix system.
IMPORTANT
In RSLogix 5000, v13 or greater, you can use a
1756-SYNCH module in a remote chassis without a
ControlLogix controller and still provide a CST value
for the chassis. I/O modules (e.g., 1756-IH16ISOE)
can use the CST value when generating timestamps.
For SynchLink systems that use RSLogix 5000, v12 or
earlier, you cannot use a 1756-SYNCH module to
synchronize I/O timestamps in a remote chassis
without first installing a ControlLogix controller in
that chassis.
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2-2 Time Synchronization in the ControlLogix System
Using the Coordinated System Time (CST)
Time Synchronization in a Distributed Control System
The Coordinated System Time (CST) is the clocking mechanism used
to achieve time synchronization in a ControlLogix chassis. The
ControlLogix Coordinated System Time (CST) clock is a 64-bit clock
on the backplane of the ControlLogix chassis. It has a 1μS resolution
and is used as the main time reference for all modules plugged into a
chassis backplane.
For more information on how the ControlLogix CST affects the
operation of other ControlLogix products, see the ControlLogix System
User Manual, publication 1756-UM001.
The same CST mechanism described above is also used to
synchronize ControlLogix chassis in a distributed control system. In
such a system, SynchLink transfers the CST value from the CST Master
chassis to CST Slave chassis.
Each chassis must be equipped with a SynchLink module and,
depending on what version of RSLogix 5000 the system is using, each
chassis may or may not require that a controller reside in remote
chassis. This distributed control system is identified as a SynchLink
system.
Time Synchronization in the SynchLink System
The 1756-SYNCH module provides synchronization of CSTs between
ControlLogix chassis provides with no more than +/-5µs drift
between chassis.
Time synchronization within a SynchLink system is required to:
• transfer a CST value from the CST Master chassis to CST Slave
chassis.
• transfer motion and drive control data.
• support time synchronization between ControlLogix chassis and
non-ControlLogix products (e.g. PowerFlex 700S products).
The SynchLink Node Clock is integral to all devices that contain the
SynchLink circuitry. It is the clocking mechanism on the fiber optic
side of the SynchLink system. This clock has a resolution of 1μS.
During system configuration, you establish one SynchLink node clock
as the master system clock on the SynchLink fiber. By design, the
ControlLogix chassis that is configured as the SynchLink master also
acts as the CST master of the system. In this manner, one SynchLink
node acts as a Time Master for the entire system. This chapter gives
more detail on how this functionality is accomplished.
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Time Synchronization in the ControlLogix System 2-3
Multiple Rockwell Automation products can be synchronized with
SynchLink. In addition to the SynchLink module, the PowerFlex 700S
and the 1756-DMxxx series products (both used for drive control) also
use SynchLink to achieve drive to drive synchronization. While all of
these products maintain interoperability, not all SynchLink features are
incorporated into every product that uses SynchLink; the 1756-SYNCH
module, however, uses all of the SynchLink features.
SynchLink Node Clock
The SynchLink node clock is integral to the SynchLink circuit design.
Any product incorporating SynchLink incorporates the SynchLink
node clock as a base-line requirement. The SynchLink node clock has
a 1μS resolution and is synchronized from node to node when the
SynchLink system is configured.
SynchLink uses a Time Master-Slave mechanism to achieve time
synchronization. During system configuration, you configure one
SynchLink node as the Time Master and all other nodes as Time
Slaves. The SynchLink node that is configured as Time Master
becomes the system clock for the entire SynchLink system. As such,
the SynchLink Time Master broadcasts its time reference to the
SynchLink Time Slaves which adjust their node clocks to be in phase
with the master clock.
Because SynchLink is a unidirectional, broadcasting mechanism, the
master is always placed at the beginning of SynchLink systems using
the star or daisy chain configurations.
Figure 2.1
Star Configuration
SynchLink
Time Master
S.L.N.C.
Hub
S.L.N.C. S.L.N.C. S.L.N.C. S.L.N.C.
SynchLink
Time Slave
SynchLink
Time Slave
SynchLink
Time Slave
SynchLink
Time Slave
S.L.N.C. = SynchLink Node Clock
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Daisy Chain Configuration
S.L.N.C. S.L.N.C. S.L.N.C.
SynchLink
Time Master
SynchLink
Time Slave
SynchLink
Time Slave
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2-4 Time Synchronization in the ControlLogix System
System Synchronization
When a SynchLink system is initialized, the individual SynchLink
nodes power-up at separate times and the individual SynchLink node
clocks begin to count at arbitrary points in time. When this occurs, the
system is not yet synchronized. As the master node clock counts, it
reaches a point where it rolls over and goes back to zero.
When the rollover occurs, the SynchLink Time Master transmits a
beacon signal to the SynchLink Time Slaves; the beacon is included in
the control field of the transmitted message. When the SynchLink
Time Slave receives the first message with the beacon signal, it begins
to adjust the 1μs time base of its node clock to synchronize with the
master clock. This process can be gradual or immediate, depending
on the product implementation.
Figure 2.2
Initial Start-Up
Master
Time adjustment
Slave
Beacon Beacon Beacon
Synchronized Operation
Master
Slave
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42983
After a SynchLink Time Slave is synchronized with the Time Master,
each SynchLink frame that is transmitted serves as a 50μS “tick” (or
mark) used for the periodic adjustment of its clock’s 1μS time base.
This process provides highly accurate results.
Figure 2.3
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Beacon signal
synchronizes
SynchLink node
clocks
SynchLink 50 microsecond message frame
serves as a “tick” to keep clocks synchronized
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Time Synchronization in the ControlLogix System 2-5
How Do the CST Clock and SynchLink Node Clock Work Together?
64-bit clock
As stated earlier, the ControlLogix Coordinated System Time clock
(CST) is a 64-bit clock on the ControlLogix backplane. It is used as the
main time reference for all modules plugged into a ControlLogix
chassis. The SynchLink node clock is used to establish the time
reference on the SynchLink fiber.
Figure 2.4 illustrates how the SynchLink node clock and the CST time
reference are coordinated in a system. In this example, the SynchLink modules
in chassis A & B synchronize the CST clock in chassis B with the CST
reference in chassis A.
Chassis A is the Time Master for the system. When the SynchLink
module strobes the beacon signal onto the fiber optic link, it also
transmits the CST time reference value that tells the downstream node
what time it is as the beacon occurs. The downstream chassis receives
the CST time reference and synchronizes its time with the CST
reference value on the beacon signal.
Figure 2.4
Chassis A Chassis B
Coordinated System Time Coordinated System Time
1756-SYNCH
SynchLink Node Clock
Configuring Time Mastership Functionality
1756-SYNCH
Clock
SynchLink beacon over the fiber optic link
You must configure each 1756-SYNCH module’s role in Coordinated
System Time (CST) Mastership. For any SynchLink system, there can
only be one SynchLink CST Time Master for the system; the Time
Master can be a 1756-SYNCH module or a ControlLogix controller. All
other devices connected to the SynchLink must be configured as Time
Slaves. However, the 1756-SYNCH modules that are Time Slaves are
Chassis CST Masters that receive the SynchLink time from the fiber
optic cable and relay it to all devices in their local chassis.
For example, the 1756-SYNCH modules in Figure 2.4 can be configured as
follows:
• 1756-SYNCH in Chassis A - MUST be SynchLink CST Master;
CAN also be Chassis CST Master
• 1756-SYNCH in Chassis B - MUST be Chassis CST Master;
CANNOT be SynchLink CST Master
For a full explanation on how to configure CST and SynchLink Mastership,
see page 3-18.
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2-6 Time Synchronization in the ControlLogix System
What are the SynchLink Configurations?
SynchLink communications are a unidirectional data transfer from one
SynchLink node to another. Each configuration starts with a single
Master Node. The SynchLink network can be configured in the
following ways.
• Star Configuration
• Daisy Chain Configuration
• Ring Configuration
Do not mix the configurations (i.e. begin in the star configuration and
change to the daisy chain configuration). Examples of these
configurations are shown in the following sections.
Star Configuration
The star configuration transfers data from a Master Node through
Hubs to End Nodes.
Figure 2.5
ControlNet
SynchLink
End Node End Node
End Node End NodeEnd NodeEnd Node
Hub Hub
IMPORTANT
Master Node
Hub
The star configuration supports 2 layers of hubs with
up to 16 end nodes connected to each hub.
A maximum of 257 SynchLink modules (including
the Master Node) can be connected in the star
configuration.
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For an example of how to configure a Star configuration, see Appendix B.
Time Synchronization in the ControlLogix System 2-7
Daisy Chain Configuration
In the daisy chain configuration, the SynchLink network starts at the
Master Node and ends at an End Node. You can include Center Nodes
(shown in Figure ) in the configuration as needed.
Figure 2.6
Master Node Center Node Center Node End Node
ControlNetSynchLink
42746
IMPORTANT
In the daisy chain configuration, you can use a
maximum of 10 nodes, including the master and
end nodes.
Also, the only difference between Center and End
Nodes is their physical location.
In the daisy chain configuration the time synchronization process is
more complicated than in the star. It’s based on the following rules.
• Each node enables its transmitter right after it has received the
first message from the upstream node.
• Each node can generate and transmit the beacon signal
regardless of whether it has received one or not.
• Each node is a Time Slave of its upstream node and will attempt
to synchronize with it.
The SynchLink Time Master node must be set as the SynchLink Time
Master. Its node clock is the SynchLink system clock. After power-up,
the Master node begins to transmit a message every 50μS. As soon as
the node connected to it receives the first of these messages, it begins
to send messages to its downstream node. Eventually, all center nodes
are transmitting messages.
As soon as a node receives the first message with the beacon signal, it
starts to synchronize its node clock with the upstream node clock. The
node connected to the Master, is the first to synchronize its clock with
the SynchLink system clock. This process then propagates down the
daisy chain until all nodes are synchronized with the Master.
For an example of how to configure a Daisy Chain configuration, see
Appendix C.
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2-8 Time Synchronization in the ControlLogix System
Ring Configuration
The ring configuration is a permutation of the daisy chain
configuration. In the ring chain configuration, the SynchLink network
starts and ends at the Master Node. You can include Center Nodes
(shown in Figure ) in the configuration as needed.
Master Node Center Node Center Node Center Node
ControlNetSynchLink
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Chapter Summary and What’s Next
IMPORTANT
For an example of how to configure a Ring configuration, see Appendix D.
In the ring chain configuration, you can use a
maximum of 10 nodes.
Cable Usage
You must use fiber optic cable to connect SynchLink modules in all
configurations. For more information on SynchLink fiber components,
see Table 1.2 and Table 1.3 on page 1-3.
For more information on choosing the correct cable lengths for your
application, see the SynchLink Design Guide, publication 1756-TD008.
In this chapter, you learned how the ControlLogix SynchLink module
fits into the ControlLogix system. For more information on SynchLink
Module Features, see Chapter 3.
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Chapter
SynchLink Module Features
This chapter describes the ControlLogix SynchLink module features.
Table 3.1
For information on: See page:
Module Features That Cannot Be Configured 3-2
Removal and Insertion Under Power (RIUP) 3-2
Module Fault Reporting 3-3
Full RSLogix 5000 Support 3-3
Status Indicator (LED) Information 3-4
Class I Division 2 Certification 3-4
Agency Certification 3-4
Use Last Configuration When Connection to Owner-Controller
Closes - For Module’s Using Firmware Revision 2.18 or Greater
Module Features That Can Be Configured 3-5
Communications Format 3-6
3-5
3
Electronic Keying 3-11
Requested Packet Interval 3-13
SynchLink Transmitted Axes 3-15
Transmitted Direct Words 3-16
CST and SynchLink Mastership 3-18
Configurable module features are features (e.g. Communications
Format) that can be configured to work differently in various
SynchLink applications.
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3-2 SynchLink Module Features
Module Features That Cannot Be Configured
These general module features (e.g. Removal and Insertion Under
Power) are supported on the module regardless of configuration and
application. The following general module features are available with
the ControlLogix SynchLink module:
• Removal and Insertion Under Power (RIUP)
• Module Fault Reporting
• Full RSLogix 5000 Support
• Status Indicator (LED) Information
• Class I Division 2 Certification
• Agency Certification
• Use Last Configuration When Connection to Owner-Controller Closes
- For Module’s Using Firmware Revision 2.18 or Greater
Removal and Insertion Under Power (RIUP)
All ControlLogix SynchLink modules may be removed and inserted
from the chassis while power is applied. This feature allows greater
availability of the overall control system because, while the module is
being removed or inserted, there is no additional disruption to the rest
of the controlled process.
Although there is no disruption to other devices when the SynchLink
module is removed and inserted from the chassis while power is
applied, the removal and insertion will break communications
between SynchLink modules and will impact the performance of the
SynchLink system.
Removing and reinserting the SynchLink module under power also
impacts overall system performance and operation because the
ControlLogix chassis are no longer synchronized. Depending on the
application, removing and reinserting the SynchLink module under
power may cause significant changes to an application, including the
possibility of a system E-Stop (emergency stop).
Because of its impact on other chassis, the removal of a SynchLink
module while under power may cause personal injury or property
damage.
WARNING
When you insert or remove the module while
backplane power is on, an electrical arc can occur.
This could cause an explosion in hazardous location
installations. Be sure that power is removed or the
area is nonhazardous before proceeding.
Publication 1756-UM521C-EN-P - July 2004
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