Posted 8 Aug 2017 (edited) I have got a FX3U-16M and -32M PLC and trying to connect with Moxa NPort 5130A serial device server to work with a scada. It seems that i dont get the modbus to communicate. I have tried the 110 ohm, 330 ohm and open setting on the device. I am making use of a 2 wire system. I have configured both the channel 1 and channel 2 of the PLC to work with MODBUS 485. i have written a program like follow M8411 ----------- Move H1087 D8400 ----------- Move H1 D8401 ----------- Move K2000 D8409 ----------- Move K400 D8410 ----------- Move K10 D8411 ----------- Move K3 D8412 ----------- Move H1 D8415 ----------- Move K100 D8416 I just need to test if there is communication from these cards. i have got 15 cards to test. Any other help will also be appreciated. Edited 8 Aug 2017 by Michielvh1 Updated the description Share this post Link to post Share on other sites
Posted 8 Aug 2017 (edited) I see D8401 is set to 1 modbus master RTU. Wouldn't SCADA be the master/Client in this case ? If so set D8401 to H11 You than should also set u the slave number in D8414 Edited 8 Aug 2017 by Gambit Share this post Link to post Share on other sites
Posted 8 Aug 2017 i have changed it as you proposed. i am testing the communication with Baseblock Com test and still it gives me an error: No Response received. I can see that the RD light flickers red but nothing on the SD light. Share this post Link to post Share on other sites
Posted 8 Aug 2017 (edited) ok but who is sending the requests SCADA or the FX3U? Baseblock comtest is that scada or the moxa? How is the serial comm parameters setup in the MOXA. Did you reset the FX3U after implementing the change? Edited 8 Aug 2017 by Gambit Share this post Link to post Share on other sites
Posted 8 Aug 2017 (edited) the request is coming from the PC. The Scada will do the sending and requesting. baseblock is just a modbus testing software that work with moxa. The settings of the comms on the moxa is the same as i configured in the PLC. I did clear the FX memory and reloaded the program Edited 8 Aug 2017 by Michielvh1 Share this post Link to post Share on other sites
Posted 8 Aug 2017 ok than the FX3U is the slave and should be H11. Can you post the settings of the moxa serial port and slave number Share this post Link to post Share on other sites
Posted 29 Nov 2019 i have same problem, i write this program in my fx3u M8411 ----------- Move H00A1 D8400 (38400, None, 8 Bit, 1 Bit, Rs232c) ----------- Move H11 D8401 (slave, Rtu) ----------- Move K10 D8411 (delay 10ms) ----------- Move H1 D8414 (Slave ID = 1) and then im try to read coil with Qmodbus, but still no respon from slave, Setting port in Q modbus and serial port at pc same 38400, None, 8Bit, 1 Bit thanks so much for yout help Share this post Link to post Share on other sites