To display signal units in your model, on the Debug tab, select Information Overlays > Port Units. To select this option programmatically, use the command-line property
With this option selected, the model dynamically updates port and signal labels to show any changes that you make to units. You do not need to press Ctrl+D to update the model. When you simulate your model, the Scope block displays units for connected signals as y-axis labels.
When you explicitly specify units on input or output blocks, block port labels and signal lines display those units. If a port is set to inherit units or has empty units, port labels and signal lines do not show labels.
With the option to display units cleared, you do not see port and signal labels, even when you press Ctrl+D to update your model. However, you do see warning or error badges for any unit inconsistency problems that exist in the model.
You can also see units in the interface view of your model. On the Modeling tab, under Design, click Model Interface.