2/18/2016 4:16 PM | |
Posts: 14 Rating:
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Hi, I am currently performing data transfer between a PLC S-1500 and S-400 PLC (Profibus DP). For this I am using the PUT & GET functions (declared in the PLC S-1500). When I modify the state of a variable in the API S-1500 (using the function PUT), the PLC S-400 « is aware » after 2 seconds of that change (for now it is reasonable). But when I change the status of a variable in the PLC S-400, the S-1500 PLC « look » the change 49 seconds later (too much !!!) GET requests are made to « get » data from an DB (size of 2600 bytes) in the S-400. I tried to optimize my program using cyclic blocks and reducing the time clocks. However, the best I have achieved so far is to reduce the time to 9 seconds (even very large !!!) calling my FB from OB cyclic. Supervision will be a huge delay !!! In a first time, I called my block OB1, but.... doesn't work (huge time) After, using a OB cyclic, goes better but not enough. So: • As I could optimize my program? Please see attachement Thanks for you feedback
Attachmentoptimizing data transfert.pdf (433 Downloads) |
2/19/2016 8:18 AM | |
Joined: 3/5/2014 Last visit: 8/5/2022 Posts: 5521 Rating:
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Hi ICOMR, maybe the Data of 2600 Bytes are to much for PUT/GET. Better will be to use BSEND/BRCV-blocks. PUT/GET is in S7-400 for at least 400 byte and in S7-1500 at least 880 byte. BSEND/BRCV can handle up to 64 kbyte. See this manual, chapter 32.2 : CPU-CPU Communication with SIMATIC Controllershope this helps, regards, |
FCK WAR! |
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