Allen Bradley Ethernet/IP tool kit


I have a stand alone system that has a PAC-R1 as the central processor. I need to connect this system with a ControlLogix PLC . I hope I can use the Ethernet/IP toolkit (or driver) and share some variables between these 2 controllers.

I need to keep the PAC-R1 running its control strategy and share some variables with the PLC.

Any one has tested this feature this way? Any Comments?



You are in luck. It is very common that users connect their A-B Logix PLCs to either our controllers or our I/O. Opto 22 controllers and Brains speak EtherNet/IP since about 2008. There is a lot of good materials on our site to help you. I’d suggest the “IO4AB User’s Guide” (Form 1909). Chapter 6 will cover your exact application. Also see at least Part 1 of this 4 part video:,KYvTRORAnx6LvLREyVV22bfaWGX9Q78Q&vid=oCIeDmM2Ovo&vidlist=true&ptitle=IO4AB Videos

One “tip” I’d like to offer as well: You’ll be doing “Implicit Messaging”, and thus your network should have a managed switch that has a setting for enabling “IGMP Snooping”. EitherNet/IP Implicit Messages are multicasts, and will turn into broadcasts and flood the network unless they are filtered (which is what IGMP does). I’ve heard in the most recent versions of RSLogix5000 (V20?) that this can be enabled in software, as opposed to having to do it in the managed Ethernet switch.

Have fun!


I am more interested on Explicit Messages, actually I have no need to expose the Opto 22 I/O rack. I only need to connect variables in the strategy with the PLC read/write both ways. Any suggestion to start with this will be highly appreciated.