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Unable to connect PC to PLC Via Ethernet


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I recently started working with the built in Unitronics PLC US7-B5-B1 and I am unable to detect the PLC when connected via ethernet. It  works fine when connected via USB, I can detect and download a new software  just not via ethernet. 
Can anyone advise me on how to troubleshoot this? My end goal is to broadcast some tags using OPCUA and I installed an OPCUA client on my PC to test the connection but am not able to establish connection with the PLC. I figured troubleshooting the unilogic detection issue my help me resolve the OPCUA issue.


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Not sure how to make that determination but when I do IPconfig in CMD, I see my subnet listed as and that of the PLC listed as (not the same).
On the PLC IP panel settings in UniApps, I see the subnet mask listed as same as mine.

Screenshot 2023-12-05 163257BA.png


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  • MVP 2023
1 hour ago, S4TUX said:

I see my subnet listed as

That is your Subnet MASK, not your subnet. Your subnet is 192.168.0. You need to make the subnet match between the PC and PLC (the first 3 octets must be the same and the 4th octet different). The subnet of the PLC, as you show above is 10.2.5.

Also, are you certain that is the IP address of the PLC? Even so, go into UniApps and change it to 192.168.0.xxx (anything other than 71). Or, you can go into your PC network settings and change your PC IP address to 10.2.5.xxx (anything other than 83). Once you do that you should be able to communicate if you are plugged into the correct port with a crossover cable or through an ethernet hub.

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Also, don't get confused between your wired ethernet address and your wireless address on your PC. When you do IPConfig in a command window, confirm which address is which since they are usually on different subnets. You want to make sure you use your wired IP address subnet.

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