Those of a diagram’s nodes that are not connected via edges but are functionally or declaratively related, for example a graphical object and a label, are configured as master and slave in such a way that the slave appears together with the master in the diagram as a unit.
The slave is typically positioned on the outer contour of the master (outside-edged).
The following screenshot illustrates as master a roller conveyor (1.) from the Bodyshell work planning diagram, and as slave the label (2.), which displays a small icon, the designation and the parameter for processing time.
Another example is a damper (1.) from a thermodynamic diagram, whose slaves (2.) indicate the direction of the current.