dipen_95

NJ501 MODBUS TCP/IP COMMUNICATION ISSUE

7 posts in this topic

I am trying to get the communication going between EZ3 EZAutomation Panel HMI and Omron NJ501-1300 PLC. I am currently using Modbus TCP/IP as a protocol.

Has anybody figured out a way to do that?

Or is there a better way to do this communication between HMI and PLC ?

Right now I am using MTCP_Client_Connect function block to connect with HMI but it dont seem to be working. The IP address is correct along with Port no. I am still fuzzy about the Station address of NJ and the function code of the NJ for Modbus purposes.

If anybody could help me out I would really appreciate it.

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Never seen an NJ function for doing Modbus/TCP.  The NJ does EtherNet/IP by default.

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The EZ3 EZAutomation Panel HMI  specifications lists A-B EtherNet/IP protocol as an available communication-driver.

Since the NJ uses EtherNet/IP by default I suggest you use it vs. ModBusTCP/IP.

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BITS N BYTES Thanks for the reply.

I have tried using Ethernet IP but no luck.

I have communication between EZ and Omron using third party function blocks but I ran into a wall when the I can only do Hexadecimal value input/output.

Attached is the function block library. If anybody can figure a way out to transfer INT instead of WORD please let me know.

MTCP_NJ.zip

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@dipen_95 the said Function Block came from myomron website actually, which was developed by Omron themselves. No, you don't need to pass an INT value to that function block.

Just use an additional INT_TO_WORD instruction then pass the result to the Function Block.

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@innoaloe I totally agree with your statement of using INT_To_WORD fuction but that only works when I am using a tag as a Numerical display but when it comes to Read/Write function whichever function is call first takes president.

FOr example if INT_TO_WORD is use to get data from HMI to NJ then I cant use the same tag to transfer the data to the HMI as INT_TO_Word will overwrite it.

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Exactly, so you need to allocate two variables

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