callizehra Posted January 9, 2021 Report Share Posted January 9, 2021 Hello, I want to read data from the engine with modbus rtu but I read zero data from the engine and also see data 5 and 4 in the error message of the rir block. i am using unitronics v700. modbus.vlp Quote Link to comment Share on other sites More sharing options...
MVP 2022 kratmel Posted January 9, 2021 MVP 2022 Report Share Posted January 9, 2021 It looks like you use panel as master and engine as slave. Master named ID1 and you try to read data from slave ID1 --- it is not correct. Please change this nodes to different ID and try to read needed data. You can change ID on engine to 2 or if it imposible - change master PLC ID to another one. Quote Link to comment Share on other sites More sharing options...
callizehra Posted January 14, 2021 Author Report Share Posted January 14, 2021 Thanks for your reply, I have made the necessary changes but it still gives a communication error. Quote Link to comment Share on other sites More sharing options...
MVP 2022 kratmel Posted January 14, 2021 MVP 2022 Report Share Posted January 14, 2021 Please post your modbus setup. Motor and drive nameplate and how modbus wires is connected to V700. Sometimes A & B RS485 wire is swaped. If you use USB connection to V700 - com port 1 is not work with modbus - it is connected to USB and Visilogic. If it possible please use PC Modbus software and USB to R485 connection for test drive communication. Please note - In drive parameter - you must configure communication settings drive ID and enable Modbus communication. Quote Link to comment Share on other sites More sharing options...
stembera Posted January 14, 2021 Report Share Posted January 14, 2021 Just a two suggestions: 1. Your software communicates via COM1. If you connect your PC via USB port of the PLC, COM1 will be suspended so the Modbus comm will not work. 2. You configure COM1 port as RS485. You must do the same on DIP switch on the PLC. Factory default is RS232. Quote Link to comment Share on other sites More sharing options...
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