1. You can check the port number of PLC through the "Equipment and Network" tab in Siemens 1200PLC configuration software.
2. In the software, select the PLC to be viewed, and then click the "Equipment and Network" tab to view the information such as the IP address, subnet mask, gateway and port number of the PLC. In the column of port number, you can see the port number used by PLC.
3. Different PLC models and configuration software versions may be different, and the specific operation methods may also be different. If you are not sure how to check the port number of PLC, you can refer to the relevant operation manual or consult Siemens technical support personnel.