I’ve got a situation where i need to keep one network seperate from another. But i also need to get modbus TCP data from both. I’m using the build in modbus TCP library.
I wanted to use the AXC F XT ETH 1TX in combination with an AXC F 2152 for this aplication. I can get the card to connect to a sepperate network and use the profinet. but i cant get it to work for modbus.
To make it more clear i want to use the AXC F XT ETH 1TX connection for a profinet and 9 modbus TCP connections, which i got to work. And then i want to setup another modbus TCP connection on the ethernet port of the PLC, this network also needs to stay sepperated. this didn’t work and this is where the problem is at the moment. i can’t use modbus TCP on 2 diffent IP’s.
At the moment we are using 1 PLC and then send the values we need over analoge ports to a second PLC. And the thing is we only need 2 values from the seperated network. so the current solution is a bit expensive.
Forgot to add: i’m using plcnext engineer 2025.6 with frimware 2024.6.1
Dear Gerard,
The situation is not 100% clear to me but maybe a NAT switch could be a solution. Is it possible for you to draw a diagram with the network, PLC’s and Modbus connections? Maybe there are also other solutions possible.
Met vriendelijke groet / Mit freundlichen Grüßen / Best regards,
Henk Welgraven
Technical Support Engineer
Industrial Electronics
PHOENIX CONTACT B.V.
ZEVENAAR
Tel. +31 (0)316 59 17 20
mailto:support@phoenixcontact.nlwww.phoenixcontact.nl
So the problem lays in the modbus connection on network B. I tested everything with network A only on single PLC and that works. but i wanted a second network which is compleetly sepparated. so we bought a AXC F XT ETH 1TX. then i read that the extention will be the new profnet card. So i built network A and tested that and that work. then i added the modbus connectoin on network B but then it gave an error that the modbus connection was out of range.
Dear Gerard,
As a test I have made an application with an Axioline ETH station and an Inline Modbus TCP station and used the build in Modbus TCP Client. The AXC has IP 192.168.1.38 and is connected to the PLCnext Controller AXC F 2152 with IP 192.168.1.10. The Inline station has IP 192.168.2.5 and is connected to the AXC F EXT 1TX with IP 192.168.2.10.
As you can see below I can read the registers of both stations.
Is it possible that you use a Function Code or Modbus address that is not supported by the Modbus station? Can you read the Modbus registers from the device with a program like Modscan32 or Modbuspoll?