as it seams we can change it using the ladder
but it is solved by
Originally Posted by Wasan View Post
You can use many PLC with Modbus TCP on same network. You should config them with seperate IP with same port no. 502 such as
PC: 192.168.1.1
PLC1: 192.168.1.2
PLC2 : 192.168.1.3
[edit] I see your problem maybe you should use VPN for connect data from network or change port to forward with other PLC such as
502 to PLC1 port 502
503 to PLC2 port 502
this what some one in plctalk site talled me to do
so i did as he said and it worked
what i did is when i opened the router to forward the port
i entered 502 for the internal port
and 503 for the external port as in the attached photo
and when i tested it to connect the plc using another internet connection
i used the port 503 and it connected normally