Hello, I am having trouble establishing communication with my SLC 5/05 PLC, which has both RS-232 and Ethernet ports. Despite trying to monitor traffic with Wireshark in promiscuous mode, I did not observe any activity from the PLC's Ethernet port. The ENET LED on the PLC is on, but the RJ45 port LEDs show no activity. I also attempted to connect using DF-1 through RSLinx, trying various configurations such as CRC and BCC error checking, as well as adjusting the station number, but was unsuccessful. Is there a simple way to connect to the PLC if I am unsure of the communication settings? If a factory reset is possible to clear any existing program, that would be ideal. Thank you.
If you're struggling to connect online due to unknown communication settings, there is a simple solution. By removing the memory backup battery and shorting the GND and VBB terminals on the controller board for 60 seconds, you can reset the device to its factory default settings. This process will erase the memory and restore the communication settings to their original configuration. No need to worry about the program inside the device – this method will do the trick. Thanks for the question!
Thank you so much, Bit_Bucket! Wishing you all the best with your coffee and coding endeavors. Good luck!
Hi there! That sure sounds frustrating. A possible reason for your difficulties could be that the PLC's communication settings don't match with those you're using. Before resorting to a factory reset, I'd suggest you try using a null-modem cable with your RS-232 port, if you haven't already, and an Auto-configure feature in RSLinx if it's available. Sometimes this method can successfully establish a connection if the protocols, data bits, and stop bits align correctly. Do remember to also check the baud rate and parity too. Lastly, don't forget to check your IP address if you're connecting via Ethernet - you might need to ensure that your computer is in the same subnet as your PLC.
Hi there! Sounds like quite the communication quandary you're dealing with. Have you checked if there's a possible hardware issue with your Ethernet cable or RS-232 port? Sometimes it's the simplest things that cause headaches! Regarding factory reset, many PLCs do have this option, but be aware that it could wipe out all settings, which may or not be what you want. You didn't mention which software you're using for programming, but typically there's an "Auto-Configure" function to automatically detect your PLC's settings. This could save you the trouble of manually trying different configurations. Remember, direct communication is often the simplest and most reliable.
Hey there! Troubleshooting connection issues like this can be quite a headache, I feel you. Given your scenario, a factory reset could be a possible solution- however, you might want to ensure there isn't important unduplicated logic in the PLC first, as a reset would wipe that out. If the PLC is in a remote location, you might also consider potential network/firewall issues. If you can, try to connect a laptop directly to the PLC via an Ethernet cross cable and see if that helps. In situations like this, simplifying the setup as much as possible can help you isolate the problem. Good luck!
Hey there! Ethernet communication issues with PLCs can be quite tricky. You mentioned the ENET LED is on, but no activity from the RJ45 port. It's possible that the Ethernet port may have a static IP address different from your subnet. Try scanning the network with an IP scanner to see if you could find the device. Regarding RS-232 communication, you might want to verify the correct cable is being used. Presence of a null modem or gender changer can cause issues. For a factory reset, you generally need a physical access to the device. You would typically have to cycle the key switch on the PLC from RUN to PROG, and then back to RUN. I highly recommend thoroughly documenting your current program before executing this if possible. Hope this helps. Good luck!
It sounds like you’ve already tried a lot of troubleshooting steps! Since the ENET LED is on but you're not seeing any RJ45 activity, I’d recommend double-checking your cable – make sure it’s not a crossover issue if you’re connecting to a switch. As for communication settings in RSLinx, don’t forget that the SLC 5/05 typically uses specific settings for baud rate, data bits, and stop bits, which can vary if the PLC was configured previously. If you can gain access to the RS-232 port, it might be worth connecting there to see if you can communicate via DF-1 and check the existing settings. As for a factory reset, just keep in mind that it will erase everything on the PLC; unless you're okay with that, it's best to explore all other options first. Good luck!
It sounds like you're dealing with a frustrating situation! Have you checked the Ethernet cable and ensured it’s properly connected? Sometimes, the cable itself can be the issue. For communication settings, if you're not sure what they are, a physical reset of the PLC might be tricky because it can erase your program, depending on the model. If a reset is possible, make sure to back up any critical data first. As a temporary solution, you could also try using the RS-232 port with a direct connection and minimal settings—sometimes less complicated setups help isolate the problem. Good luck!
It sounds like you've covered a lot of ground already, but to simplify things, I'd recommend double-checking that the Ethernet settings on the PLC match those on your PC—sometimes a mismatch in IP addresses or subnet masks can cause communication issues. If you're not sure what settings are currently configured, you could try connecting via the RS-232 port, as it might be more stable for initial setup. Regarding the factory reset, while there isn't a standard way to reset the SLC 5/05 like you might find on other PLCs, you can usually load a default program from a known working backup if you have access to one. Just ensure you have backups of any existing programs before doing anything drastic!
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Answer: Answer: One approach is to attempt a factory reset on the PLC to clear any existing settings and programs. This can help in establishing a new connection without the need for specific communication settings.
Answer: Answer: You can try using tools like Wireshark to monitor network traffic and observe any activity from the PLC's Ethernet port. Additionally, attempting to connect through RSLinx using DF-1 protocol with different configurations such as CRC and BCC error checking, and adjusting the station number, may help establish a connection.
Answer: Answer: If the ENET LED is on but there is no activity on the RJ45 port LEDs, it indicates that the PLC is powered and Ethernet is enabled, but there may be issues with the network configuration or communication settings that need to be addressed to establish a successful connection.
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