HMI interface

The communication between PLC and HMI is conceptually considered in the Plastic Application. This ensures that controlled access of the HMI to the PLC is possible. In addition, it is also quickly apparent in PLC programming that the respective sections are input and/or output values of the HMI.

The concept is for each class with information exchange to be given a second class, which assumes precisely this function. This results in the parallel-class model. In addition to the main class (FB_Xyz), there is a parallel class of type FB_XyzHmi for each added class. The parallel class is linked to the main class via an interface. In the instantiation, the instance of the parallel class must be passed to the instance of the main class for this purpose. Depending on the use case, the main class of the parallel class can also be passed in this step.

This arrangement results in a division of control data and user input/display values. In addition, controls from the T8550 Plastic TC HMI Controls are implicitly supported, greatly improving the integrity of the project. In the same way, recipe management can be optimally linked to and used with the PLC.