In this dialog, you can define units for time, mass, energy or volume and choose the display units.
Here, you can see already existing unit definitions. If necessary, new ones can be defined.
All entered or calculated values will be displayed in one unit (= display unit) within the system diagram. Because you can enter data with arbitrary units, you have to decide which unit you want to choose as display unit. This can be done independently for each layer (goods, substances, energy).