2/7/2014 1:51 PM | |
Posts: 6 Rating: (0) |
Dear Sirs, Appreciate if you can kindly help me to solve the problem that I encounter. First of all, I'd like to admit that this is the first time I do the Modbus TCP communication programing with Siemens PLC. I am currently set up the communication with S7-315 2PN/DP plc (as client) and Wartsila engine controller called as UNIC-C2. UNIC-C2 is acting as modbus slave device (slave number is 5) and TCP port is 502. All data available from UNIC C2 is holding registers (FC3). The total information that I shall read from UNIC C2 to my Siemens PLC are more than 400 bytes. Modbus Addresses of UNIC-C2 is started from 410001 to 48105 as last address. The address are not sequence. Here is the configuration of both PLC & UNIC C2. IP address of S7-315 2PN/DP : 192.168.0.2 IP address of UNIC C2 : 192.168.0.3 Modbus Slave No of UNIC C2 : 5 Port No : 502 I tried to use the Modbus_PN_CPU_Example program from sample projects and configured Modbus parameters with Modbus TCP Wizard. I attach herewith the procedure and my observation from step by step. In short, I got communication but the data is only 125 bytes that I can read. It looks like I only managed to send/receive ONE telegram and not going to next telegram. Hence, please kindly guide me where and how I shall program in OB1 to get the next data telegram to read all data from my slave device, UNIC C2. Thank you in advance for your kind guidence and correction on my program. AttachmentModbus TCP Data Mapping.pdf (689 Downloads) |
2/10/2014 10:49 AM | |
Posts: 6 Rating: (0) |
Thanks Sakura, I think I managed to get the communication (tested with a few address). Attached herewith the program that I had tried to create. It looks pretty OK now. Kindly let me know if there are any abnormal in my attached program. Thank you all in once again. Best Regards Traung AttachmentModbus Logic.pdf (585 Downloads) |
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