Hello everyone, I am currently facing connectivity issues between my Modicon M241 PLC and Magelis HMIS5T HMI through Ethernet using SoMachine v4.1 programming environment. Although I have successfully programmed the PLC and configured the HMI, I am receiving an error message stating "Failed to open connection to PLC (PLC_SzennyKecsed)." PLC_SzennyKecsed is the assigned nodename for the PLC. Interestingly, when simulating the HMI on my PC, communication with the PLC works fine, allowing for tag read/write operations. It is worth noting that my programming PC is running on Windows 7 Ultimate 64bit. Can someone please suggest any troubleshooting steps or things I should double-check to resolve this issue? Thank you, Boti.
If you're experiencing connectivity issues between a PLC and an HMI, make sure the PLC's IP address matches the HMI's gateway. This simple fix can resolve the problem and ensure smooth communication between the devices. Sharing this troubleshooting tip in case it helps others. - Boti
It is recommended to keep the gateway as 0.0.0.0 unless your PLC is on a separate subnet. When you set a gateway, you are instructing the HMI to access the PLC by going through the gateway IP address. This setup only functions when the PLC matches the gateway IP address.
Hello CapinWinky, I understand your point. However, when the gateway is set to 0.0.0.0, it causes the Human-Machine Interface (HMI) to have communication issues.
Hello, I am experiencing the same issue as mentioned in a previous post. I am attempting to download a program via ethernet, but I keep encountering a connection error. When I try to "download all" in SoMachine, I am unable to download the HMI. Could this issue be related to the device address of the PLC? I have attempted using gateway 0.0.0.0, PLC IP, and router IP, but to no avail. Can anyone provide a helpful tip or solution for this problem?
To troubleshoot connectivity issues between a PLC and HMI, verify that the Nodename matches on both sides in the IO Manager. Additionally, disconnect all programming cables from the devices to prevent any potential interference from the PC instead of the PLC's ethernet or serial connections. Hopefully, these steps can resolve the issue. Thank you.
Hi Boti, it seems like there could be a few potential reasons for your connectivity issue. First, you might want to double-check your ethernet cable and its connections on both, the PLC and HMI side. Another common issue could be IP address settings. Make sure your HMI and PLC are on the same subnet and there aren't any IP clashes. Since you've mentioned the simulation on your PC runs without any problems, it's clear the programming logic is correct, so it's likely to be a hardware or network setup issue. Also, are there any other devices on the network that might be causing traffic congestion? I'd try to isolate the HMI-PLC communication to see if that makes any difference. Lastly, you may also want to consider updating your SoMachine to the latest version or checking with Schneider Electric support for specific software bugs that might exist with the v4.1 running on a Windows 7 platform. Good luck!
Hi Boti, it sounds like you've already run through some solid initial troubleshooting. Just to double-check a few things though, have you made sure all IP addresses are correctly set within the same subnet for your PLC, HMI, and PC? Sometimes connectivity issues can arise from minor discrepancies in setting IP addresses. Also, firewalls or antivirus software on your programming PC could interfere with the connection, you might want to check that. If everything is okay on this front, I'd suggest exploring the possibility of a cable or port issue. Try replacing the Ethernet cable or switch the port to rule out hardware issues. Let me know how it goes!
Hi Boti, I've faced similar issues in the past. An often overlooked aspect is the Ethernet link itself. Make sure your cables and Ethernet switch or hub are functioning properly and confirm your PLC is reachable from other devices on the same network. Another thing to check is your firewall settings on the PLC and/or the PC. Sometimes, certain communications can be blocked, even if the PLC and HMI are properly configured. Lastly, ensure you're using the same software versions that were used for programming on both your PLC and HMI, as version mismatches can cause unexpected issues at times. Hope this helps!
Hey Boti, it seems like you've done a great job with programming and configuring. Your mention of it working during simulation on your PC strongly suggests a communication problem between your HMI and PLC, likely not related to software. I recommend checking your Ethernet connection - i.e., cabling, switches, port settings. It would be smart to verify that you're using the correct type of cable (crossover or straight-through, depending on your setup). Also, ensure that the static IP addresses of PLC and HMI are correctly assigned and lie in the same subnet. Hopefully, with these suggestions, you'll manage to establish a connection! Good luck.
Hi Boti! It sounds like you're off to a good start with the programming, but connectivity issues can be tricky. Since you mentioned that the simulation works fine, I'd suggest double-checking the actual network settings on both the PLC and HMI to ensure they’re in the same subnet. Also, make sure that any firewalls on your Windows 7 system aren't blocking the Ethernet ports used for communication. Lastly, verify that the nodename and IP address are correctly configured in the HMI settings. Sometimes a fresh restart of both devices can also help reset any lingering connection issues. Good luck!
Hey Boti! It sounds frustrating to deal with those connectivity issues, especially since it works in simulation. Have you checked the IP addresses and subnet masks of both the PLC and HMI to ensure they're on the same network range? Sometimes it could be a simple IP conflict. Also, make sure that any firewalls or antivirus software on your Windows 7 machine aren’t blocking the communication ports used by SoMachine. Lastly, try restarting both devices to reset the connection, and if possible, check for any firmware updates for the HMI or PLC that might fix potential bugs. Good luck!
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Answer: Answer: The error message could be due to misconfigured network settings, incorrect nodename assignment, firewall issues, or communication protocol mismatch between the PLC and HMI.
Answer: Answer: The discrepancy in communication behavior could be related to network configurations specific to the physical HMI device, such as IP address settings, subnet masks, or firewall restrictions.
Answer: Answer: Ensuring compatibility between the hardware components (PLC, HMI) and software environment (SoMachine v4.1) is crucial for establishing a stable Ethernet connection. Checking the device compatibility matrix provided by the manufacturers can help address any compatibility issues.
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