What is the PLC system you are using? If you are using Rockwell you should have RSLinx utility, which allows you to easily change the IP setting mode from BOOTP or DHCP into fixed IP settings. If you are not using Rockwell PLC you can still download the RSLinx Lite utilities free of charge, but you need to register in the Rockwell website.
There is also a freeware from Molex called the ODVA Tools utility. It is a little bit rough, after all it is free of charge, but it is extremely powerful. It has a tab for the TCP/IP Interface object and there you can change the Configuration Control instance attribute value.
Hello and thank you very much for the reply; I am using rockwell but unfortunately I can't change IP from RSLinx.. probably wrong pins setted on module?
You need to make sure that the IP settings for the PC's network interface card is in a subnet compatible with the IP settings of the EtherNet/IP device. You write that you managed to setup an IP address. What IP address did you set on the device and what is the IP address of the PC's NIC to which the device is connected?
Plc, beckoff and pc are under “192.168.1.xxx” and same subnet 255.255.255.0.
I can see all the module on RSLinx and open config for change IP on PLC, but not in beckhoff.