WKla

Modbus TCP/IP Multimaster

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Hi everybody, Hardware: Q03UDE CPU with Ethernet interface. Software: GX Works 2. I use the library for the Modbus TCP/IP (server-slave) for built-in Ethernet (article id on beijer site: DSSE-8QDHC7(GX Works) or DSSE-8RHGF5(GX IEC)). Can I use two modbus TCP Clients (Master) for getting data from the PLC? Thank you.

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Yes, but you must use 2 connections, one for each "Master" (Client)

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I went to the location and indeed only one master can connect to the PLC. The problem is that the library supports only one connection: "ConnectionNo" is "the Socket communication connection number to be used." So the only possibility would be to use two functions.

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Correct, you can use two functions (FBs)

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Hello WKLA , FB you have shown uses Q06 CPU , but you are using "Hardware: Q03UDE CPU with Ethernet interface. Software: GX Works 2." Does it function OK ? In my project I have Q03UDE CPU with Ethernet interface , is it possible to make built in Eth as ModTCP server , so that my Modbus SCADA can read/write ? Regards, Shriram Pendse

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I once had some issues when using 2 Modbus server blocks in a FX3U Project. Made some Changes to the system at the same time I changed Connection 2 to use port 1025 instead of 502. It's been working for quite some time now, but I really don't know if the port change was the solution to the issues.

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It is working fine. I use 2 FB's but I only one TCP Client. There is no one to connect to the other function. Edited by WKla

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Hello WKLA , Yes , it works , I could make Q03UDE CPU with Ethernet interface as " ModTCP client " and it talks to AdvancedHMI VB.net application successfully. Thanks for the inputs you provided .

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On 6/14/2013 at 11:27 PM, WKla said:

Hi everybody, Hardware: Q03UDE CPU with Ethernet interface. Software: GX Works 2. I use the library for the Modbus TCP/IP (server-slave) for built-in Ethernet (article id on beijer site: DSSE-8QDHC7(GX Works) or DSSE-8RHGF5(GX IEC)). Can I use two modbus TCP Clients (Master) for getting data from the PLC? Thank you.

Hi WKla,

Could you please share the library Modbus TCP/IP (server-slave) for built-in Ethernet (DSSE-8QDHC7(GX Works)), I checked your code on beijer but I could not download  it.

Email: du.pham.ab@gmail.com

Thank you.

BR.

 

Edited by du.pham.ab

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Good Day All

can one use Q03UDE CPU to talk Modbus TCP to external devices?

Thank you

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