12/19/2018 1:44 PM | |
Posts: 4 Rating: (0) |
Thanks for answer, but I searched through that and it didn't helped me. First of all, how I need to connect two PLC-c? |
12/19/2018 2:22 PM | |
Joined: 9/27/2006 Last visit: 9/18/2024 Posts: 12282 Rating: (2684) |
Hello prga; What manuals have you been reading exactly? For programming, configuring and networking S7-200 PLCs, the first manual you should look at is the S7-200 System manual: https://support.industry.siemens.com/cs/ww/en/view/1109582 Chapter 7 is dedicated to networking the S7-200s, and give a lot of information on connecting the CPUs over PPI and using the NETR and NETW instructions. There is also a networking wizard available in MicroWin to make your life even easier. The connection cable between the PPI programming ports is RS-485, so you an easily build your own if needed, straight connection of pins 8-8, 3-3 and 5-5 (+ shield grounding) with a shielded twisted-pair cable and Sub-D 9-pin connectors. But if you want to add another unit connected to the CPUs (a programming PC for example)at the same time as your network, you should think of Profibus cable, with Profibus connectors having a piggy-back connector allowing the programming cable to connect. See page 223 of the suggested manual for an example. The attachment below shows the networking insructions available in MicroWin to exchange data between CPUs over a PPI network. Hope this helps, Daniel Chartier |
Last edited by: dchartier at: 1/17/2019 6:27:36 PM |
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1/18/2019 8:44 AM | |
Posts: 4 Rating: (0) |
Hello, Main question -> communication between two S7-200 Cpu-s with Modems EM241. |
1/18/2019 4:22 PM | |
Joined: 9/27/2006 Last visit: 9/18/2024 Posts: 12282 Rating: (2684) |
Hello prga; Siemens has discotntinued the S7-200 CPUs and EM 241 since 2017: https://support.industry.siemens.com/cs/ww/en/view/109749165 Siemens generated very interesting documents named Micro Automation Sets (MAS) that showed application projects and sample code for different projects. MAS 13 was dedicated to EM 241 configuration and programming. Unfortunately, they have been removed from the Siemens archives, and the central site for these libraries (www.siemens.com/microsets) is no longer reachable. There are still some presentations available on the web for MAS 13, such as this one from Siemens Belgium, in French. No code attached, though... Mybe someone here has the MAS 13 on his computer and could send you a copy? https://www.siemens.be/eit/microautomation/fr/set13.asp In the meantime, the best source of information on the configuration and connection of EM 241 modems to a telephone network would be chapter 10 of the S7-200 System manual. Data Transfers The Modem module allows your program to transfer data to another CPU or to a Modbus device over the telephone line. The data transfers and telephone numbers are configured with the Modem Expansion wizard, and are stored in the Modem module configuration block. The configuration block is then downloaded to the data block in the S7-200 CPU. The Modem Expansion wizard also creates program code to allow your program to initiate the data transfers. A data transfer can be either a request to read data from a remote device, or a request to write data to a remote device. A data transfer can read or write between 1 and 100 words of data. Data transfers move data to or from the V memory of the attached CPU. The Modem Expansion wizard allows you to create a data transfer consisting of a single read from the remote device, a single write to the remote device, or both a read from and a write to the remote device. Data transfers use the configured protocol of the Modem module. If the Modem module is configured to support PPI protocol (where it responds to STEP 7--Micro/WIN), the Modem module uses the PPI protocol to transfer data. If the Modem module is configured to support the Modbus RTU protocol, data transfers are transmitted using the Modbus protocol. The telephone number of the remote device, the data transfer request and the data being transferred are read from the CPU over multiple CPU scan cycles. Your program should not modify telephone numbers or messages while a message is being sent. Also, you should not modify the data being transferred while a message is being sent. If the remote device is another Modem module, the password function can be used by the data transfers by entering the password of the remote Modem module in the telephone number configuration. The callback function cannot be used with data transfers. Hope this helps, Daniel Chartier AttachmentS7_200_SysMan_ EM 241.pdf (303 Downloads) |
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