Connect 2 controllers with EtherNet/IP through a router

[exopphase 0]

Dear All,

I'd like to ask whether it is possible to connect 2 PLCs (both have EtherNet/IP capability) through a router.

Here is the case :
- We have 3 machines each with Compact Logix AB PLC.
- We need to retrieve data from each Compact Logix AB PLC, to an Omron NX PLC via EtherNet/IP Protocol
- The problem is, currently each of the Compact Logix PLC has same IP addresses, since they are OEM machines installed with no integration in mind before.

- The OEM & customer, doesn't allow us to change the IP address of the PLC.
- The solution we could think of is to do NAT with router, the thing is we are not really sure whether EtherNet/IP could be translated by NAT.

Thank you 

[IO_Rack 178]

Allen Bradley makes a device specifically for this reason. 9300-ENA NAT device. I have successfully communicated Omron and AB via this type of connection.

[exopphase 0]

On 8/13/2020 at 0:48 AM, IO_Rack said:

Allen Bradley makes a device specifically for this reason. 9300-ENA NAT device. I have successfully communicated Omron and AB via this type of connection.

Hi IO_Rack, thank you for the answering reply, appreciate it !  We'll surely look at the mentioned NAT device.  Just out of curiosity, will a standard off the shelf router do the job as well?

[BobLfoot 301]

I believe the 9300-ENA is going obsolete in favor of the 1783-NATR and other Stratix NAT and routing devices.

To answer your question any Industrial Grade Router and most Consumer Grade Routers should be able to do NAT.

If you're at all Security conscious you'll want to Firewall the PLC and open / NAT only the ports needed for Ethernet/IP.

I've used the 9300-ENA and 1783-NATR with all our OEM for the past five years. 

Our machine build spec actually requires the OEM to leave a space on the DIN Rail for the NAT and a dedicated 24 VDC fuse to power it.