fersra

Hello, Has anyone tried Modbus TCP Toolkit? http://www.modbus.org/toolkit.php We are stating to implement Modbus for communicate several PLCs and it costs round 500$ and I don't know if it worth. The content of the toolkit: Modbus Application Protocol Specification, V 1.0 and Modbus Messaging on TCP Implementation Guide, Rev. 1.0 Tools (easy to find on internet) Modbus/TCP Client Diagnostic Tool and Modbus/TCP Server Diagnostic Too (I don't know what it is) Sample Source Code Modbus/TCP Sample Client and Server Code for several languages and OS (I have some example that I got on other sites, such as http://libmodbus.org/ ) Modbus/TCP Conformance Test Software (I suppose that are some test software to prepare for Modbus conformance certification, but does anyone exactly on what consists those test? ) I have tried to send an e-mail to modbus.org but I have no response so far. Thanks.

I don't know how RTU works and maybe I am wrong but, can a master connect to more than one slave at the same time? Slave opens 502 port for listening request of Masters and if the slave is a Multithreaded server, it could manage a lot of clients or masters. The system architecture is Redundant Slave PLCs with dual NIC's connection to a layer 3 switch to the redundant Schneider Masters PLCs. The PLC servers or slaves have dual redundant communication 2 x NICs for the primary server and 2 x NICs for the secondary server. Each server is connected to redundant switches. On the other hand, The PLC clients or masters have dual redundant communication 2 x NICs for the primary client and 2 x NICs for the secondary client. Each client is connected to the respective redundant switches that are connected the servers. If the any primary PLC fails, the second PLC would take over operation. But I don't know yet how I should manage the commands in order to detect duplicate messages or commands or how I should keep refreshed every couple of PLCs (primary and secondary) Can you think of anything? Thanks

Hi, Does anyone know if Modbus is able to work properly with redundant networks? I am new on this area. I want to communicate several slaves and masters PLC devices each other and every device will have 2 ethernet ports. I am concerned about detecting duplicate commands or detect disconnections of my devices. What do you suggest about it? Thanks.

Hello, I am new in Modbus and in this forum so sorry if I am posting this in the wrong place. I would like to create an scenario (first simulate and then with real PLCs) with several masters connected to a several slaves where I am able to test the communication each other with Modbus TCP. It should be necessary work with redundant networks where every device should have 2 ethernet ports (with differents IP's) in order to get availability. I have seen a lot of programs on internet but I don't know if there is a useful tool with client and server functions to test communication, with ability of communicating with multiple master and slaves and work with redundant networks (I don't know if this is possible). I don't mind if the program is not freeware. Do you suggest anything? If you don't know any with the ability of work with redundant networks, could you recommend me the best simulator in your opinion? I have tried SimplyModbus and Modbus Poll from modbustools.com so far. By now, I prefer the last one. Thanks.

Hello, I am a beginner in Modbus and I need a Modbus TCP Client. The programs you said before don't fit what i need. I want a useful tool with client and server functions to test communication and develop without hardware (at the moment), Modbus traffic monitoring. Moreover, it should be able to communicate with multiple master and slaves and work with redundant networks (I don't know if this is possible).I have found a lot of free and shareware programs on internet but none of them can work with redundant networks. Do you know of a program that would fit the purpose? or even if it is possible to do something like this? I don't mind if the program is not freeware. More details, I would like to create an scenario with several masters connected to several slaves where I am able to test the communication each other with Modbus TCP. It should be necessary work with redundant networks where every device should have 2 ethernet ports (with differents IP's) in order to availability. Do you suggest anything? Thanks.