Connect Serial Cable from Terminal Blocks to Computer Comport for Bridge Configuration

Transcription

1 Tech Note 391 Configuring Modicon Modbus to Ethernet Bridge 170-CEV All Tech Notes and KBCD documents and software are provided "as is" without warranty of any kind. See the Terms of Use for more information. Topic#: Created: January 2005 Introduction This Tech Note describes how to configure the Modicon Modbus to Ethernet bridge 170-CEV , in order to use the bridge and Wonderware Ethernet servers (MBENET I/O server, MBTCP DAServer, or MBTCP DI object), acting as a master, to communicate with Modbus serial devices (also called end devices or slaves). The Tech Note also briefly describes cable configurations needed for the bridge's configuration and for the RS232 communications to the end devices. Note: Although the bridge is capable of either RS232, RS422, or RS485 serial communications to the end devices, we will only set up the RS232 serial interface in this Tech Note. Assumptions A basic working knowledge and understanding of Modicon bridge, TCP/IP and Modbus RTU/ASCII protocols Ethernet and serial communications Microsoft HyperTerminal For more information regarding configuration and connections to and from the bridge, please refer to Schneider Electric's Modicon Modbus to Ethernet bridge 170 CEV User's Guide, or contact Schneider Electric's technical support. Connect 174-CEV Bridge to Power Supply First of all, the bridge needs to be connected to a power source of 9 to 30 VDC. It is important to provide a protective fuse at the power source to protect the bridge from short circuit. The following figure (Figure 1 below) shows the power wiring and the earth ground connections to the bridge: FIGURE 1: POWER WIRING Connect Serial Cable from Terminal Blocks to Computer Comport for Bridge Configuration Next, we will connect a serial cable from the wiring terminal blocks to a computer Communication port (COM port) so that we can configure the bridge. Figure 2 (below) shows the connections from the terminals to a DB9 female connector: 1/5

2 FIGURE 2: SERIAL CABLE FROM TERMINAL BLOCKS TO DB9 FEMALE CONNECTOR FOR BRIDGE CONFIGURATIONS Configuring 174-CEV Bridge Using RS232 Port from Terminal Blocks Now, you should be ready to configure the bridge so that the Wonderware Ethernet servers (MBENET I/O server, MBTCP DAServer, or MBTCP DI object), acting as a master, can access Modbus slave device via Ethernet TCP/IP - Bridge - Modbus connections. Make sure the following configuration is in place before you start configuring the bridge: Obtain an Ethernet IP address for the bridge (from your network administrator). Obtain an Ethernet Gateway IP address if it is applicable to the network. Determine the serial interface type to the end device. Is it RS232, RS422, or RS485. This tech note demonstrates configuring the RS232 serial interface. If it is RS422 or RS485 serial communications to the end device, please refer to the 174-CEV User Guide for more information regarding RS422 and RS485 cable configurations. Note the Serial port communication parameters. These parameters must match with that of the end device. Determine the Modbus protocol type. Is it RTU or ASCII? If applicable, obtain modem control parameters for RTS and CTS timing values. If applicable, obtain Modbus timeout values for character and message timeouts. What is the address source? Is it from Unit_ID header or Fixed Address? With the RS232 cable from the Terminal Blocks (as shown in section 2 above) connected to a computer's COM port (COM1 is being used in this tech note), we are ready to use the Microsoft HyperTerminal program to configure the bridge. HyperTerminal 1. Launch the HyperTerminal by selecting Start/Programs/Accessories/Communications/HyperTerminal. 2. Enter a meaningful name for the new connection, then click OK. The Connect To dialog box appears. 3. Select COM1 from the Connect using drop-down list as shown in Figure 3 (below): 2/5

3 FIGURE 3: SELECT THE CONNECTION 4. Click OK to open the COM1 Properties dialog window (Figure 4, below). 5. Enter the following parameters for the bridge configuration: Bits per second 9600 Data bits 8 Parity None Stop bits 1 Flow control Hardware The dialog box is shown in Figure 4 (below): FIGURE 4: COMMUNICATION PARAMETERS FOR BRIDGE CONNECTIONS 6. Click OK to accept the communication parameters. We need to force the bridge to go into configuration mode: On the HyperTerminal window, first, hold down the X key on the keyboard, then press the Reset button on the bridge to initialize it. A window displaying Schneider Automation and the bridge information should now be visible. Please take a note about the firmware version. It is highly recommended that the firmware must be at version 1.6 or greater. Figure 5 (below) shows a typical bridge's configuration that is connected directly to a RS232 Modbus serial slave device: 3/5

4 FIGURE 5: 174-CEV FIRMWARE CONFIGURATION WINDOW Connect to Slave Device 1. Connect an Ethernet cable to the RJ45 Ethernet port on the bridge. Connect the other end of the cable to the application's network. 2. Set the Serial Port switch to up position for RS232 serial communication. 3. Insert one end of a Modicon serial cable, such as RJ45-RJ XCA cable, into the RJ45 Modbus port. 4. Connect the other end of the cable to a RJ45-DB9 Female adapter 110 XCA Connect DB9 (Male to Female) null modem connector. FIGURE 6: TCP/IP AND SERIAL CONNECTIONS B. Nguyen Tech Notes are published occasionally by Wonderware Technical Support. Publisher: Invensys Systems, Inc., Rancho Parkway South, Lake Forest, 4/5

5 CA There is also technical information on our software products at Wonderware Technical Support For technical support questions, send an to back to top 2013 Invensys Systems, Inc. All rights reserved. No part of the material protected by this copyright may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, broadcasting, or by anyinformation storage and retrieval system, without permission in writing from Invensys Systems, Inc. Terms of Use. 5/5