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| 6/5/2023 7:37 AM | |
Joined: 3/30/2020 Last visit: 1/20/2026 Posts: 5667 Rating:
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Have a look at the following application example: It may not be the drive you work with, but it sure has many pieces of general information that is very helpful. For your drive you need to find out how to set the Modbus RTU related settings. It will be of the same kind as mentioned in the example. |
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| 6/5/2023 6:27 PM | |
Joined: 4/26/2017 Last visit: 10/13/2025 Posts: 78 Rating:
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hello sir 1- exact model: 6ES7-241-1CH32-0XB0 using RS485 as the protocol 2- i already checked the CFW500 and can't find something useful about it. I found a video were the expert shows how to read parameters from the CFW500 but i have no idea how to do things like manage the speed, run/stop, read errors, etc.
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Last edited by: Jen_Moderator at: 06/06/2023 05:15:38Video embedded. |
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| 6/5/2023 6:38 PM | |
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Joined: 4/26/2017 Last visit: 10/13/2025 Posts: 78 Rating:
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thanks! i will check this guide, but since i am not familiar with s7 1200 and modbus, i might find it difficult.
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| 6/5/2023 7:30 PM | |
Joined: 9/27/2006 Last visit: 1/16/2026 Posts: 12481 Rating:
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Hello Walther; In that case, I would suggest you start by getting a basic understading of Modbus RTU exchanges, as it is independant of the platform you want to use, in this case Step 7 and S7-1200. Our good friend smiffy is considered an expert on Modbus RTU, he has studied it diligently over his working career, up to the point of programmng his own Modbus driver on a PLC in one of his projects. He has prepared an introductury article on Modbus RTU that you will find in the first post here: https://support.industry.siemens.com/forum/ca/en/posts/modbus-general-description/66876 The rest of the discussion can also be helpful , since it deals with questions members here had on working with Modbus and the S7 platform they want to use. Once you have a bit more familiarity with the Modbus communication structure, you will understand what you must look for in your CFW500 manual: the Modbus register mapping and their associated Modbus addresses, the Modbus functions you must use to read/wite to different Modbus datatypes (input registers, holding regiters...). Then you can search for the Step 7 manual for the version you are working with, and lstudy the Modbus instructions your S7-1200 supports and how they are designed to work. You will find it easier to start your programming with that basic knowledge. and you can use the Modbus RTU application examples from the SIOS (like the one provided by quazee) with more clarity. Hope this helps, Daniel Chartier |
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