Ethernet/IP Explicit Messaging Using Unity Software

Transcription

1 Data Bulletin 8000DB /2010 Raleigh, NC, USA Ethernet/IP Explicit Messaging Using Unity Software Retain for future use. Overview Presumption Requirements This data bulletin illustrates how to setup Ethernet/IP (EIP) slaves and memory address assemblies for implicit messaging. NOTE: This document does not detail how to setup implicit messaging using Unity software. This bulletin is written for individuals familiar with Unity software and networked Altivar 71 variable speed drives (ATV71). If you are not familiar with this software or network operation, please consult your system administrator. The following hardware and software is required: Hardware Premium logic controller TSXETC100 Ethernet/IP module Ethernet switch (TCSESM083F23F0) Altivar 71 variable speed drive (VW3A3316 Ethernet/IP card installed) Software Unity version 4.1 Ethernet/IP configuration tool

2 Ethernet/IP Explicit Messaging 8000DB1025 Overview 07/2010 Table of Contents Overview... 1 Presumption... 1 Requirements... 1 Safety Information... 3 Notice... 3 Related Documents... 3 Product Related Information... 4 User Comments... 4 Introduction... 5 Background... 5 Application Example... 6 Overview... 6 Using the Ethernet/IP Config Tool... 7 Using Unity Software

3 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Safety Information Safety Information Notice Read 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 procedure. A lightning bolt or ANSI man symbol in a Danger or Warning safety label on the equipment indicates an electrical hazard which, as indicated below, can or will result in personal injury if the instructions are not followed. The exclamation point symbol in a safety message in a bulletin indicates potential personal injury hazards. Obey all safety messages introduced by this symbol to avoid possible injury or death. Symbol Name Lightning Bolt ANSI Man Exclamation Point DANGER DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury. WARNING WARNING indicates a potentially hazardous situation which, if not avoided, can result in death or serious injury. CAUTION CAUTION indicates a potentially hazardous situation which, if not avoided, can result in minor or moderate injury. Related Documents The following technical publications and other technical information can be downloaded from our website at Title of Documentation ATV71 Programming Manual Reference Number atv71_programming_manual_en_ ATV71 Communication Parameters Manual v Premium TSXETC 100 EtherNet/IP Communication Module User Manual 3

4 Ethernet/IP Explicit Messaging 8000DB1025 Safety Information 07/2010 Product Related Information WARNING LOSS OF CONTROL The designer of any control scheme must consider the potential failure modes of control paths and, for certain critical control functions, provide a means to achieve a safe state during and after a path failure. Examples of critical control functions are emergency stop and overtravel stop. Separate or redundant control paths must be provided for critical control functions. System control paths may include communication links. Consideration must be given to the implications of unanticipated transmission delays or failures of the link. 1 Each implementation of an Altivar 71 must be individually and thoroughly tested for proper operation before being placed into service. Failure to follow these instructions can result in death, serious injury, or equipment damage. 1. For additional information about anticipated transmissions delays or failures of the link, refer to NEMA ICS 1.1 (latest edition), Safety Guidelines for the Application, Installation, and Maintenance of Solid State Control and to NEMA ICS 7.1 (latest edition), Safety Standards for Construction and Guide for Selection, Installation and Operation of Adjustable-Speed Drive Systems or its equivalent in your specific country, language, and/or location. User Comments We welcome your comments about this bulletin. You can reach us by at oem.solutions@schneider-electric.com. 4

5 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Introduction Introduction Background Ethernet IP is based on the Common Industrial Protocol (CIP). For the programmer,there are two messaging systems that are of interest: Implicit Messaging: This is the most used and programmatically requires the least overhead. This form of messaging is an I/O scanner in which the master device repeatedly queries the slave devices. The rate of implicit messaging to a specific slave device is dictated by the Request Packet Interval value (RPI). Most devices handle the implicit messaging for the programmer so the internal details are completely abstract. Explicit Messaging: It involves a finite number of I/O variables. For example, a standard Ethernet/IP assembly for the Altivar 71 drive has eight inputs and eight outputs. The explicit messaging system provides a process to handle parameters that need to be processed occasionally or only once during the life of the program. Explicit messaging is a direct link to a device on an Ethernet/IP network similar to a traditional master-slave configuration used by Modbus. So why not always use explicit messaging? Programming overhead is high. Performance is compromised. As explained above, implicit messaging is normally handled automatically by the system. Explicit messaging needs to be manually performed and managed at the application level. Industrial fieldbus protocols are primarily for the control of external slave devices. That is, the majority of bandwidth consumption comes from the rapid, repetitive scanning of external slaves. Ethernet/IP has a predictable set of matrixes for the calculation of bandwidth and performance. The predictability, however, comes from Implicit messaging, combined RPIs, and assemblies for slave devices on a network to derive a bandwidth in packets per second. Adding in large quantities of Explicit messaging makes it much less predictable. The management is being handled by the application and is subject to scan times, program logic, and so forth. As a result, the overall performance of an Ethernet/IP network becomes less predictable. 5

6 Ethernet/IP Explicit Messaging 8000DB1025 Application Example 07/2010 Application Example Overview Figure 1 illustrates the test setup used for this example. The drive is interfaced to the TSX ETC 100 module using standard Ethernet cabling and is set to run using implicit messaging. This example does not go into the details of how to setup implicit messaging using the Unity software. NOTE: Explicit messaging details are occurring in conjunction with the implicit messaging. Figure 1: Overview of the Test Setup Ethernet Altivar 71 TSX ETC 100 Ethernet Switch 6

7 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Application Example Using the Ethernet/IP Configuration Tool The Ethernet/IP configuration tool is an add-on for Unity software that is primarily used to setup the EIP slaves and memory address assemblies for implicit messaging. See Figure 2. Placing the tool into online mode permits use for explicit messaging duties. Figure 2: The Ethernet/IP Configuration Tool screen For this example, the Acceleration (ACC) parameter is set remotely using explicit messaging. Figure 3 shows the ACC parameter from the ATV71 Communication Parameters User s Manual. Both the Ethernet/IP and DeviceNet share the same logical foundation Common Industrial Protocol (CIP). The DeviceNet address takes the form of CLASS/INSTANCE/ATTRIBUTE. Figure 3: The ACC Parameter 7

8 Ethernet/IP Explicit Messaging 8000DB1025 Application Example 07/2010 The Ethernet/IP configuration tool has an explicit messaging dialog box that is available when the tool is in online mode. The online button is part of the toolbar above the IP address information shown in Figure 2 on page 7. Once online, click on the Network Detection tab to access Online Action. See Figure 4. Figure 4: Accessing the Online Action Tool 8

9 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Application Example Click on Online Action to open the Explicit Messaging tool. See Figure 4 and 5. The Explicit Messaging tool contains the following information: The IP and DeviceNet addresses display in the IP Address and Class fields. The default for the IP Address, Class, Instance, and Attributes fields is a decimal number. Click on the button to the right of the field to toggle between decimal and hexidecimal. NOTE: The use of an IP Address implies that the device is a slave. On the Service pane the Name drop-down menu contains a selection of CIP messages to send. The selections include: Reset, Get Attribute Single, Set Attribute Single, and so forth. Click Send to Device to send the explicit message to the slave device. Figure 5: Results of Sending the Get Attributes Single CIP Figure 5 shows the results of sending the Get Attributes Single service message to the slave drive. The value (1E 00) is received back from the ATV71 for the ACC parameter. The Ethernet/IP actually swaps the lower byte with the higher byte so that the received value shown in Figure 5 is 30 or 3.0 since the ACC parameter is 0.1 seconds. The Status box indicates that the Explicit message was succesful. 9

10 Ethernet/IP Explicit Messaging 8000DB1025 Application Example 07/2010 It is also possible to set parameters using explicit messaging. Figure 6 demonstrates this using the Explicit Messaging tool. The Data section displays (hexadecimal). This implies a decimal value of 50, or a 5.0 second ACC parameter value. This CIP command is also successful and the ATV71 now has an ACC value of 5 seconds. Figure 6: Setting the ACC Value 10

11 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Application Example Using Unity Software While the Ethernet/IP configuration tool is good for demonstrating explicit messaging, it is not a programming solution to be used in an application. Explicit messaging via Ethernet/IP is accomplished in Unity through the SEND_REQ function block. Figure 7 shows the SEND_REQ function block in a very simple program. The documentation for explicit messaging using this block is found in the TSX ETC 100 manual. The I/O for this block includes the following: ADDR the address of the TSXETC100 Ethernet/IP module and its location within the processor rack. As an example, the address shown in Figure 7 is made up of: Rack = 0 Module = 6 Channel = 0 Destination Address = 1 (The target device as specified in the Ethernet/IP configuration tool. Figure 4 on page 8 shows the example drive having an IP address of and is referred to as device 001.) Code a static hexadecimal (E) which signifies a CIP request. EMIS the data to send array. The array can be variable in length based on the type of message being sent and amount of data. For this example, it is a 6-integer array to contain the CIP message data. GEST the management parameter array which is handled by Unity. The information in this array is setup by the program prior to a send request and then the logic controller populates it based on the results of the transmission. RECP the data array that stores received response message information from the slave device. Figure 7: SEND_REQ Function Block 11

12 Ethernet/IP Explicit Messaging 8000DB1025 Application Example 07/2010 Most of the setup to do an explicit message occurs in the EMIS and GEST arrays. Figure 8 on page 13 shows the contents of the three I/O arrays prior to a Get Attribute Single CIP command. The arrdatain array is fed by the RECP output array of the SEND_REQ function block. It is zeroed out prior to a transmission attempt. The arrdataout feeds the EMIS input of the SEND_REQ function block and is where the CIP message is actually constructed. It has the following elements: arrdataout[0] is set to hexadecimal 0 to imply that the Ethernet/IP message is unconnected. arrdataout[1] is set to hexadecimal 030E with the high byte implying the CIP Request Path Size and the low byte being the CIP message type. So the low byte (0E hex) is the Get Attribute Single CIP service request. arrdataout[2] is set to hexadecimal 8E20. The low byte (20 hex) is static to imply the CIP Class Segment. The high byte (8E hex) is the class element of the DeviceNet address. See Using the Ethernet/IP Configuration Tool on page 7. arrdataout[3] is set to hexadecimal Similar to arrdataout[2], the low byte (24 hex) is static to imply the CIP Instance Segment. The high byte represents the Instance element of the DeviceNet address. See Using the Ethernet/IP Configuration Tool on page 7. arrdataout[4] is set to hexadecimal Similar to arrdataout[2] and arrdataout[3], the low byte (30 hex) is static to imply the CIP Attribute Segment. The high byte represents the Attribute element of the DeviceNet address. See Using the Ethernet/IP Configuration Tool on page 7. arrdataout[5] is the data payload word and is not used for the Get Attribute Single CIP command, but will be in the following example. 12

13 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Application Example The arrmgmnt array is fed input and output to GEST. It has the following elements: arrmgmnt[0] has a high byte that is the exchange number which is managed by Unity. It shows 1C hexadecimal because other data exchanges have been performed with this program. The low byte, which is the Activity Bit, is also managed by Unity. This parameter can be monitored to determine when the transmission response back from the slave device has been received. arrmgmnt[1] has the Operation Report occupying the high byte and the Communication Report in the low byte. These values are populated by the SEND_REQ function block to convey the success or failure of a transmission down to the hardware level. These bytes are populated when the activity bit (see above) transitions from 1 to 0. The encoded SEND_REQ function block values for these bytes are available in the Unity online help. Figures 8 and 9 show the value of 3E00 hex. The lower byte is the Communication Report and implies that a Correct Exchange has occurred. Since this is a successful transmission, the 3E hex value for the Operation Report is the Request Code for the positive reply. arrmgmnt[2] represents the time-out value in milliseconds. As shown in Figure 8, it is set to 0 which indicates an infinite time-out period with the slave. This should be set to 250 milliseconds so the time-out occurs if the slave does not respond within the specified time period and the Communication Report will notify the caller. arrmgmnt[3] represents the total number of bytes that make up the transmission packet. In Figure 8, the number of bytes in the transmission packet is A hex or a 10 byte packet request. Figure 8: State of the I/O Arrays Feeding the SEND_REQ Function Block Prior to Transmission 13

14 Ethernet/IP Explicit Messaging 8000DB1025 Application Example 07/2010 Figure 9: State of the I/O Arrays Feeding the SEND_REQ Function Block Post Transmission Figure 9 shows the results of the Get Attribute Single request sent to the ATV71 slave. The following bulleted lists details some of the results. Based on the Communication Report the transmission was succesful. The number of bytes in the management array shows a total of 6 responses from the drive. The exchange number in the management report increments by 1. The data input array contains the 6 bytes received; the value 32 hex is populating it. This corresponds to the 5 seconds ACC value set in Using the Ethernet/IP Configuration Tool on page 7. The Get Attribute Single request was successful and valid based on the value set in Using the Ethernet/IP Configuration Tool. Figures 10 and 11 demonstrate the Set Attribute Single performed in a similar manner to the example above. The drive ACC parameter is set to 1 second. The second element in the data output array is 0310 hex instead of 030E in the previous example. The lower byte is set to 10 hex, which is the CIP code for Set Attribute Single. The sixth element of the data output array is set to 000A hex (the value of the parameter to set). The ACC parameter is set to 1 second, which is decimal 10 (in 100ths of a second). The fourth element of the management array is set to 000C hex (the transmission packet is 12 bytes long including the parameter value). 14

15 8000DB1025 Ethernet/IP Explicit Messaging 07/2010 Application Example Figure 10: State of the I/O Arrays Feeding the SEND_REQ Function Block Prior to Transmission Figure 11: State of the I/O Arrays Feeding the SEND_REQ Function Block Post Transmission 15

16 Ethernet/IP Explicit Messaging 8000DB1025 Data Bulletin 07/2010 The outcome of the Get Attribute Single command is that the drive ACC parameter is set to 1 second. These values are being set appropriately in the drive in real-time. However, they are not stored to EEPROM memory and a reboot will force the previous parameter values to be returned. NOTE: The current state of the parameters can be saved to EEPROM by writing the extended command word. See page 61 of the ATV71 Communication Parameters Manual. Schneider Electric USA, Inc Knightdale Blvd Knightdale, NC USA Altivar and Premium are registered trademarks of Schneider Electric. Other trademarks used herein are the property of their respective owners. Electrical equipment should be installed, operated, serviced, and maintained only by qualified personnel. No responsibility is assumed by Schneider Electric for any consequences arising out of the use of this material.