eWon Flexy 101 reach different subnet

I am trying to read values from two Rockwell PLCs on different but similar subnets using a Flexy 101.
I have looked at the following discussions but I am still not succeeding:

My configuration is as follows:
The main PLC is configured to use two IPs, for the main control network and for a diagnostic network. The main network is on 192.168.119.xx and the diagnostic network is on 192.168.120.xx. The HMI, eWon Cosy and eWon Flexy are on the diagnostic network. The second PLC, that I am unable to read, is on the main network.

I set the Cosy’s IP to I set the IP of the Flexy to, default gateway (Cosy), and subnet mask In the Flexy I configured two ABLogix servers: (PLC1) and (PLC 2). I receive data for the PLC 1 but get errors for PLC 2.

When I connect to the network from my computer using the Talk2M VPN of the Cosy, I can reach PLC 1 and PLC 2. This tells me the routing between the two subnets must be possible.

Am I misconfiguring the subnet of the Flexy? What should I change to allow the Flexy to reach the PLC on the 192.168.119 network?

Hi Stephan,

It is difficult to follow the network layout here. Could you provide a diagram of the layout?

What i suspect might be an option here would be to use the cosy’s NAT 1:1 feature to add/map the device from the main network on to the diagnostic network.


Hi Deryck,

Please see the network layout in the image.

In this network, the Flexy can read values from PLC 1 but not from PLC 2.

When connecting remotely through the Cosy via Talk2M VPN, it is possible to connect to both PLC 1 and PLC 2 from the desktop.

I had a quick look at NAT on the Cosy but understood that the NAT is to route traffic from the remote desktop to the Cosy’s LAN. IS that correct? Or can the Cosy also route traffic between the 192.168.119.xx and 192.168.120.xx subnets?


It seems like there is some misunderstanding on how subnets work. If this photo is accurate I am not sure how the cosy has access to the network and PLC.
If the networks are connected together, this would really mean you are setting up a 192.168.x.x network bridging the two. I don’t think this is what you want. This combines both networks as one. If this is the case you could try change the MASK on the Flexy to .

I don’t know you full network layout and use case so I can’t say for sure, you may want to discuss this with a Network engineer. What I would recommend NAT1:1 maps a LAN device to a static ip on the WAN side of the ewon.

You would have the LAN network of the cosy connected on the 192.168.119.x subnet and map the two PLC to the WAN network adapter in the 192.168.120.x range. the Flexy would then be connected on the 192.168.120.x subnetwork Mapped to Mapped to