Access Control System for Controlling Access of a User to One or More Operating Functions of a Technical Installation

An access control system for controlling access of a user to one or more operating functions of a technical installation, the access control system comprising:

• a receiving device configured to read access authorization data from a mobile data medium and
• an access control device configured to receive and validate the access authorization data from the receiving device,
• wherein the receiving device is further configured to (i) continuously add a dynamic portion to the access authorization data to create dynamic access authorization data and (ii) send the dynamic access authorization data to the access control device and
• wherein the access control device is further configured to, in response to the dynamic access authorization data corresponding to a defined expectation, generate a release signal for those operating functions for which the access authorization data is valid.