Posted 8 Dec 2018 Hi Folks, I'm trying to establish communication with a CompactLogix L35E. I removed this processor from an used machine and I do not know the IP address. My Computer IP is 192.168.1.5. How can I establish communication? Any help will be highly appreciated. Thanks, Anthony Share this post Link to post Share on other sites
Posted 8 Dec 2018 (edited) Hello Anthony. Firstly welcome to the forum. There isnt a straight forward-answer to this i'm afraid but you do have several options. 1. If you have the correct serial cable you could connect intially via RSLinx then set a new IP Address using RSLogix5000. The cable you need would be a 1756-CP3. 2. If you know the subnet range in the PLC- if you make sure your PC is on the same and connect via ethernet- RSLinx may be able to check this way. Otherwise the BOOTP Utility could be used if the hardware address (MAC Address) is known. 3. If you have the original machine program that this PLC was removed from- the intial IP Address will be stored in here (assuming the memory card is sill intact). By all means you can send me the program (if you have it available) and I can check for you. Regards Daniel Edited 8 Dec 2018 by collinsd70 Share this post Link to post Share on other sites
Posted 8 Dec 2018 Hi Daniel, Thank you for the quick response. I was able to communicate using serial port USB-SR232 cable but I would like to communicate via Ethernet. The processor is blank, no original machine program and I do not know the subnet range on the processor. Best regards, Anthony Share this post Link to post Share on other sites
Posted 8 Dec 2018 (edited) Okay, in this case I would create a new Project in RSLogix5000. You need to match your project revision to the firmware revision on the CPU (lets say for example 15.1). This info will be on the CPU itself or check via the RSLinx window Once the project is built- download to the controller, whilst online go to your controller properties and go to Internet Protocol, here it will give you the option to manually set an IP Address and a Subnet Mask, once complete apply via 'Set' and your good to go... The other option is to click your ethernet module properties in the RSLinx tree and apply the same setting there- but Enivitabiy you will have to create a project at some point regardless. Edited 8 Dec 2018 by collinsd70 1 person likes this Share this post Link to post Share on other sites
Posted 8 Dec 2018 There are a number of free pieces of software out there that will let you scan a network and tell you what device has what IP. address. If your laptop and the PLC are the only devices on the network it’s pretty easy to figure out what the PLC IP is. Angry IP Scanner (I know, weird name but it works) is simple but you would need to know the subnet mask and subnet of the PLC. So that’s no help Wireshark is the better option in this case. Connect your laptop and PLC to a switch, let Wireshark run for a bit, there should be two IP addresses in the list of data Share this post Link to post Share on other sites
Posted 14 Dec 2018 You can set the IP once you're online with the processor. Share this post Link to post Share on other sites