Secure Operation of the PLC
To increase security when operating the PLC with the loaded application, you need to encrypt communication with the PLC with a certificate (device security settings).
You also need to use the device user management. This also includes a password policy and login lock, as well as the activation of an interactive login mode.
The use of various PLC operating modes and the audit log function are additional security-relevant tools.
You could also use a library to define at runtime when specific critical operations must not be executed.