IP Address Conflict on Ethernet Network between ControlLogix Controllers


Thread Starter


Two AB Control-Logix controllers in two different locations (different countries) have same IP address. They are on an Ethernet network.

They are not supposed to talk to each other. We just need to be able to monitor them both from either locations. We have data logging software that looks at tags from both systems. Is it possible to connect them together without having an IP address conflict?

IT says I have to change IP address on the PLC side. That is not going to be easy as there are so many sub parts in the machine that talk to each other on Ethernet including drives.

Please help!

David Wilson

Isolate these controllers from the Wide Area Network (WAN) with routers or other device that can be configured with Network Address Translation (NAT). I use the Siemens SCALANCE S6xx, it can be configured to limit connections to only the systems that you want to allow. It sounds like your IT Department has spread one subnet across their entire WAN; not wise.