Communication ports

[Greg 0]

Hi to all, i would like to know if there is an option to disable or to lock with password the communication ports on S7-300 and S7-400 PLC's? Thanks in advance for looking and helping. Best Regards, Greg.

[JesperMP 2]

Hi greg. You cannot lock a port specifically, apart from disabling it completely. You can password protect a complete CPU, which will block accessing the code blocks, but that does not block changing values of variables in the PLC. In the latest version STEP7 5.5 you can create encrypted individual blocks that cannot be accessed at all without the password. But it still does not block changing values of variables.

[Greg 0]

Thank you Jesper, you say there is a possibility to disable the port completely, how or where i do that? Thank's in advance for you help Greg.

[JesperMP 2]

On a CPU with a MPI and a DP port, you cannot disable the MPI port, but you can disable the DP port. Simply set the DP port to "not networked". On a CPU with a MPI and a PN port, you cannot disable the MPI port, but you can disable the PN port. Simply set the PN port to "not networked". The PN port is still reachable via its MAC address. But to use the port for online access would require a download of a modified HW configuration. The MPI port can also be set to "not networked", but it will still be accessible for online access.

[Greg 0]

Thank you very much Jesper. you helped me a lot. Thousand thanks!