Modicon Modbus Plus Network Planning and …

1 Modbus plus Network Planning and installation Guide890 USE 100 00 Version 2890 USE 100 00 November 2004890 USE 100 00 November 20043 Table of ContentsSafety Information .. 7 About the Book .. 9 Chapter 1 Introducing the Modbus plus Network .. 11 Introducing the Modbus plus Network .. 12 Network Terminology .. 14 Overview of the Logical Network .. 16 Overview of the Physical Network .. 17 Major Components of the Network .. 20 How Nodes Access the Network .. 28 Error Checking and Recovery .. 30 Designing for Process Speed .. 31 Designing for Deterministic I/O Servicing.

2 32 Using Peer Cop .. 33 Expanding the Network .. 36 Joining Modbus plus Networks .. 39 Bridging Modbus plus and Serial Devices .. 42 Chapter 2 Elements of Network Planning .. 47An Overview of Network Planning .. 48 Defining the Network Components .. 50 Defining the Network Layout .. 52 Chapter 3 Estimating Network Performance .. 55 Estimating Network Performance .. 57 Factors for Planning .. 59 How Devices Interact on the Network .. 60 Factors That Affect Performance .. 61 Communication Paths and Queuing .. 63 Reading and Writing with the MSTR.

3 65A Sample MSTR Communication .. 67 Getting and Clearing Statistics .. 69 Reading and Writing Global Data .. 71 Loading Effects in Your Application.. 724890 USE 100 00 November 2004 Predicting Token Rotation Time.. 74 Formula for Calculating Rotation .. 75 Predicting MSTR Response Time .. 76 Estimating Throughput (With MSTR) .. 78 Estimating Throughput (With Peer Cop) .. 80 Predicting Node Dropout Latency Time .. 82 Estimating Latency for a Small Network .. 84 Estimating Latency for a Large Network .. 86 Planning for Ring Join Time.. 88 Precautions for Hot Standby Layouts.

4 90 Guidelines for a Single Network .. 91 Guidelines for Multiple Networks .. 95 Sample Communications Across Networks .. 98A Summary of Network Planning .. 100 Chapter 4 Documenting the Network Layout .. 101 Documenting Your Network Layout .. 102 Worksheets for Network Planning .. 103 Defining Your Node Requirements .. 104 Topology Planning Worksheet .. 106 Estimating Cable Lengths .. 108 Reviewing Your Topology Plan .. 109 Detailing the Network Layout .. 110 Network Planning Worksheet.. 112 Cable Routing Worksheet .. 115 Materials Summary Worksheet.

5 118 Chapter 5 Installing the Network Cable .. 121 Overview of the Cable installation .. 122 Tools and Test Equipment Required .. 123 Before You Start .. 124 Routing the Cables .. 125 Mounting the Taps .. 127 Connecting the Trunk Cables .. 128 Connecting the Drop Cables .. 131 Grounding .. 133 Labeling .. 134 Checking the Cable installation .. 135 Chapter 6 Connecting an RR85 Repeater .. 137 Mounting Methods .. 138 Mounting Dimensions .. 139 Installing the Repeater .. 140 Reading the Network Indicators.. 143RR85 Repeater Specifications.. 144890 USE 100 00 November 20045 Chapter 7 Connecting a BP85 Bridge plus .

6 145 Mounting Methods.. 146 Dimensions (Panel/Shelf Models) .. 147 Dimensions (Rack Mount Model) .. 148 Setting the Modbus plus Addresses .. 149 Connecting the Power Cables.. 150 Connecting the Network Cables .. 152 Applying Power .. 153 Reading the Network Indicators .. 154 Attaching Port Identification Labels .. 156BP85 Bridge plus Specifications .. 157 Appendices.. 159 Appendix A Modbus plus Transaction Elements .. 161 Transaction Timing Elements .. 162 The Message Format HDLC Level .. 166 The Message Format MAC Level .. 167 The Message Format LLC Level.

7 168 Appendix B Message Routing .. 171 The Modbus plus Message Routing Path .. 172 Modbus Address Conversion .. 174 Controller Bridge Mode Routing .. 175 Bridge Multiplexer Routing .. 177 Appendix C Planning Worksheets .. 183 Appendix D Installing Custom Cable Systems .. 195 Installing the Network Cable System.. 196 Tools and Test Equipment Required.. 197 Before You Start .. 198 Routing the Cable .. 199 Installing Connectors on Dual-Cable Runs .. 201 Installing Connectors with the Tool .. 202 Installing Connectors without the Tool.

8 209 Grounding .. 216 Labeling.. 217 Checking the Cable installation .. 218 Glossary.. 219 Index.. 2296890 USE 100 00 November 2004890 USE 100 00 November 20047 Safety InformationImportant InformationNOTICERead these instructions carefully, and look at the equipment to become familiar with the device before trying to install, operate, or maintain it. The following special messages may appear throughout this documentation or on the equipment to warn of potential hazards or to call attention to information that clarifies or simplifies a addition of this symbol to a Danger or Warning safety label indicatesthat an electrical hazard exists, which will result in personal injury if theinstructions are not is the safety alert symbol.

9 It is used to alert you to potential personalinjury hazards. Obey all safety messages that follow this symbol to avoidpossible injury or indicates an imminently hazardous situation, which, if not avoided, will result in death, serious injury, or equipment indicates a potentially hazardous situation, which, if not avoided, can result in death, serious injury, or equipment indicates a potentially hazardous situation, which, if not avoided, can result in injury or equipment Information8890 USE 100 00 November 2004 PLEASE NOTEE lectrical equipment should be serviced only by qualified personnel.

10 No responsi-bility is assumed by Schneider Electric for any consequences arising out of the use of this material. This document is not intended as an instruction manual for untrained persons. 2004 Schneider Electric. All Rights USE 100 00 November 20049 About the BookAt a GlanceDocument ScopeModbus plus is a local area Network system for industrial control applications. Networked devices can exchange messages for the control and monitoring of processes at remote locations in the industrial products supporting Modbus plus communication include programmable controllers and Network adapters.