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How to Communicate with Schneider Modicon M580 PLC Using Python over Ethernet

Question:

I am seeking assistance in developing a Python script to communicate with a Schneider Modicon M580 PLC using an Ethernet connection. Any insight or guidance on this matter would be greatly appreciated.

Top Replies

Are you wondering if the Modicon M580 is compatible with Modbus protocol? If that's the case, you may find a solution in using the pymodbus library. I have explored its capabilities for gathering data from electrical meters, and I am impressed by its robust features and functionalities. You can find more information about pymodbus at https://github.com/riptideio/pymodbus.

The M580 PLC system natively supports Modbus TCP/IP integration, with a built-in client feature. However, it does not have native support for free TCP socket use. To enable socket communication, one can opt to utilize Modbus TCP or consider utilizing a third-party module. When inquiring about standard TCP communication possibilities with M580, Schneider recommended using Modbus TCP/IP or exploring third-party solutions. Implementing a Modbus server in your Python application is necessary for utilizing Modbus TCP/IP, either through programming or utilizing existing libraries compliant with the protocol. Modbus TCP operates as a client/server protocol, where the client sends a request with a function code, and the server processes the request and provides a response.

Yes, it is possible to communicate with it using Ethernet TCP/IP without relying on Modbus. Python will act as a server, making the script with sockets straightforward. However, configuring it on Unity Pro can be a bit complex.

While Modbus may not be the most advanced protocol available, having a protocol in place for communication is essential. Utilizing Modbus, a widely supported protocol, is generally more dependable and less complex than creating a custom protocol from the ground up. Of course, this is just my personal perspective.

In his specific scenario, utilizing a raw socket may prove to be a simpler solution compared to incorporating a Modbus library or creating a custom Modbus server. Unfortunately, native support for this feature is not available on the M580 PLC, unlike Siemens, Rockwell, and some Schneider PLC models (such as Premium and possibly M251). This limitation could be seen as a significant drawback of the M580/M340 system. For more information on the M580 module, refer to the documentation available at http://www.niobrara.com/apps/pmeucm/tcpopen/PMEUCM_TCPOPEN.pdf. Pricing and performance of this module remain uncertain at this time.

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Hey guys! I'm looking for guidance on writing Python scripts for Modbus TCP server to transmit data to my PLC. Additionally, I'm seeking advice on how to configure Unity Pro to receive this data. Can you help me out with this?

According to Iner, utilizing a raw socket would be a more straightforward solution in his situation compared to incorporating a Modbus library or developing his own Modbus server. I initially believed that the CPU inherently supports ModbusTCP. In my experience, the Python library I referenced effectively fulfills the role of a Modbus server, handling data type conversions and endianness smoothly.

Othmane expressed his gratitude and inquired about writing Python scripts for a Modbus TCP server to communicate with a PLC using Unity Pro. Creating a Modbus server can be time-consuming as you would need to implement the protocol yourself. You can refer to the GitHub link provided by cardosocea for assistance. To configure the M580 side, open your Unity project and navigate to the tools tab to access the "open DTM navigator" for network configuration. The M580 supports EIP and Modbus/TCP natively. Add devices you wish to communicate with using the "Generic Modbus device" option, assigning an IP address and defining communication parameters. Ensure to understand how to utilize the DTM tool effectively.

Cardosocea mentioned that they initially thought the CPU had built-in support for ModbusTCP. However, the Python library they shared has effectively served as a Modbus server, handling data type conversions and endianness. The M580 does have strong native support for Modbus TCP. Yet, integrating Modbus into a Python application can be more challenging compared to using a standard raw socket for a PC application. Modbus operates on top of the TCP stack, which Schneider doesn't provide direct access to. If the user only needs to display values on their PC or send characters for printing, they may not require full Modbus functionality with its registers, acknowledgments, handshakes, and communication timeouts. However, if they require IO exchanges for control, using Modbus is a more suitable choice over raw sockets.

In this guide, we provide two visual examples to demonstrate the process of configuring modbus requests on the M580 platform.

Iner pointed out that integrating Modbus into a Python application can be more challenging compared to using a raw socket, which is a common practice for PC applications. It is worth noting that there is already a Python module available for Modbus communication. The original poster (OP) seems to be focused on sending characters for printing or displaying values on their PC. However, if data exchange beyond a single value is required, a protocol is necessary. Developing and implementing a protocol through sockets may be more time-consuming than utilizing an existing solution like Modbus, which could offer a more efficient alternative.

Uncertain of its usefulness, pycomm is a comprehensive package consisting of modules specifically designed for interacting with PLCs. The primary module within pycomm, ab_comm, is currently available for use. Explore more about pycomm at https://pypi.org/project/pycomm/ to enhance your PLC communication capabilities.

Hey everyone, I am trying to establish communication between a Schneider Electric M580 PLC and a printer using Ethernet IP. I am looking to send data from the PLC to the printer for printing, but I am unsure of how to go about it. Can anyone provide assistance on this matter? Thank you!

Hello everyone, I am looking for assistance in establishing a connection between an M580 and a printer using Ethernet IP. My goal is to transmit information from the PLC for printing purposes, but I am unsure of how to proceed. Can anyone provide guidance on this matter? Feel free to start a new thread for better visibility and assistance.

Frequently Asked Questions (FAQ)

FAQ: FAQs:

Answer: 1. How can I communicate with a Schneider Modicon M580 PLC using Python over Ethernet? Answer: To communicate with a Schneider Modicon M580 PLC using Python over Ethernet, you can use libraries like Modbus TCP or libraries specific to Schneider PLCs. You will need to establish an Ethernet connection and use the appropriate protocol for communication.

FAQ: 2. Are there any specific Python libraries recommended for communicating with a Schneider Modicon M580 PLC?

Answer: Answer: Yes, you can use libraries such as pymodbus for Modbus TCP communication or libraries provided by Schneider Electric for interacting with their PLCs. These libraries provide functions to read and write data registers on the PLC.

FAQ: 3. What steps are involved in developing a Python script for communication with a Schneider Modicon M580 PLC?

Answer: Answer: The steps involved include establishing an Ethernet connection with the PLC, selecting the appropriate communication protocol (e.g., Modbus TCP), writing Python code to send and receive data from the PLC, and handling any errors that may arise during the communication process.

FAQ: 4. Are there any specific considerations or settings to keep in mind when communicating with a Schneider Modicon M580 PLC over Ethernet?

Answer: Answer: Yes, you need to ensure that the PLC is configured to allow communication over Ethernet and that the IP address and port settings match those in your Python script. Additionally, consider the data types and formats supported by the PLC for proper data exchange.

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