OPC server connection to the PLC via Cosy131

Ewon Support eWON Cosy
#1

Hi there,

I do have a lot of eWON cosy 131 installed on site on various different machines connected to the various different brand PLCs. The primary purpose for them is a remote OEM support.
I would like to utilise the NAT1:1 functionality of these units to access the PLC from the factory LAN to collect the production data by means of the OPC server.

I am testing this with Omron PLC and I am encountering the problems reaching the tags from WAN side of the eWON.

Kepserver configuration has been tested on the LAN side of the eWON and is working fine. I would expect the OPC server to be able to read the tags through the NAT routing in the same way.
I can ping the PLC and go online with CX-Programmer from eWON WAN side with no problems.

As I can access the PLC through the eWON NAT with programming software, but not with the OPC server, problem seems to be on the OPC server side. The strange thing is that the configuration has been tested on the LAN side of the eWON.

Any help in this matter will be much appreciated.

#2

Yes, I would also expect this to work. We may have to do a packet capture to determine what the problem is.

Another possible solution is to use a Proxy (Port Forwarding) if you know which ports are being used.

I would recommend creating case at support.hms-networks.com so your local support team can take a closer look at this. Please send a backup of the Ewon with the Support files. You can download one from the web interface under ‘Diagnostics > Files Transfer > Support Files’ or use eBuddy to create one.

Thank you!