samuraipanda

Thank you very much i copied the program from the examples in the manual. I should have done more research beforehand. I do think i got what you mean but is there any example code that i can study from? And other then that is there any other probable cause? And what is triggering those warnings in the log?

Here are the error log in csv and a screen shot of the fw version. It would seem that the udp communication between the fx5u and the q series plc is to blame. As if we would stop the q series plc the error will stop. But if we put the q series plc back in run mode the fx5u plc will revert back to its error state. That is as far as what i observed  PLC Error Log.csv

Hallo kaare_t You are right i am using mc protocol sorry for my mistake. Let me explain the whole system the fx5u plc is communicating to 2 keyence sr 1000 using mc protocol, 1 q-series plc using udp and a scada application using modbus tcp. We have issues where the fx5u plc will suddenly disconnect its ip would be missing and gx works cannot connect. We then have to put the plc in stop mode to be able to connect using gx works. When we put the plc on run the error happens again. This has happen several times in random occasions witch makes it hard to troubleshoot. Sometimes stopping the plc and re writing the program will fix the problem temporarily. Attach is the program. In the program block scanner is where we did the program for the 2 keyence sr 1000 In the program block coms is where we did the program for the udp communication settings. I am using gx works 3 version 1.0472.  As the plc firmware i dont know. pc 20180121 sore.gx3

I have a fx5u plc connected to 2 keyence sr 1000 qr code scanners using plc link. On random times the plc error light will light up and all ethernet connection will be disconnected and i cannot connect to the plc with gx works 3. If i put the plc in stop mode tho i can connect to the plc. I do not know what error code is causing this because each time i connect the error code is missing. The problem starts when the plc is in run mode. Can anyone help me with this as this is a persistent bug that keeps on happening in my system?