2/7/2009 2:20 PM | |
Joined: 9/27/2006 Last visit: 2/6/2025 Posts: 12333 Rating:
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Hello patel; The CP 341 is a serial processor for the S7 CPU. You state you want to connect the MP 270 (an operator interface) to a DCS system over Modbus... am I correct? Then why are you considering PLC hardware? Open the following manual on WinCC Flexible communications to non-Siemens PLCs: http://support.automation.siemens.com/WW/view/en/11165960 Study the chapter on Modicon PLCs (over Modbus). You will see that the Modbus driver is included in the package of WinCC Flexible, without external software. The manualstates you can establish a point-to-point connection to any Modbus slave PLC (the MP 270 will be master on this connection). This should work with your DCS system, as Modbus is a generic format. You can probably use any Modicon PLC type for this, the 984 are the oldest CPUs, the Quantum the most recent. Just make sure that you have the correct cable, the correct slave setup on the DCS, and the right programming in the DCS, as per the instruction in the document provided. When you have studied this and tried this connection, tell us how it goes. Hope this helps, Daniel Chartier |
2/9/2009 7:38 AM | |||||
Joined: 9/27/2006 Last visit: 2/6/2025 Posts: 12333 Rating:
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Hello patel; As always, it is better if you define the parameters of your problem before looking for solutions. First, your S7 can be Modbus master or Modbus slave on this exchange. If the DCS is going to be master, then the S7 CP 341 must be a slave. If the CP 341 is master, the DCS must be programmed as a slave. This is the first information you need to clear up. The attached document will give you a basic understanding of Modbus exchanges, function codes.... so you can better phrase you problem. Depending on the master or slave configuration you decide upon, the CP 341 must recieve a "loadable driver" for Modbus (master or slave, they are different) and it will require a small dongle to be inserted in the CP itself in order to operate. Here is some information on that issue: CP 341, Modbus RTU master loadable driver manual: http://support.automation.siemens.com/WW/view/en/1220184 Part number of the Modbus master dongle:
CP 341, Modbus RTU slave loadable driver manual : http://support.automation.siemens.com/WW/view/en/1218007 Part number of the Modbus slave dongle:
You will also need to assign parameters to the CP 341; the software comes with the module, here you can find the manual: CP 341 parameter assignment manual: http://support.automation.siemens.com/WW/view/en/1117397 |
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2/11/2009 11:07 AM | |
Posts: 134 Rating:
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HI..... THANK YOU VERYMUCH for your detail help..... from all those manuals i have understood lot of things and checked my problem according to that....i have DCS as master and CP341 as slave..So, i have used modbus slave driver. but now the problem is, i have power-up my system. after few seconds SFLED of CP goes off. Means my configuration is ok...?am i right...? ifi am..then prob is my TXDor RXD any LEDis not coming....i have used serial interface card on DCS side..and connecting cable i have designed as per the drawing i have attached..i have also checked baud rate and etc on DCS side.. pls guide me in this problem its important and urgent... here i am attaching my PLC program and connecting cable wiring drawing for your reference.. AttachmentPLC Program.zip (207 Downloads) |
Last edited by: patel at: 2/11/2009 11:13 AM |
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2/11/2009 11:10 AM | |
Posts: 134 Rating:
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here i am attaching my PLC program and connecting cable wiring drawing for your reference..
Attachments7300_cp_341_manual_en-EN.pdf (188 Downloads) |
9/19/2012 12:24 PM | |
Posts: 19 Rating:
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i want to appriciate for your help, it work too me ...tanx |
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