Defining a Variant Subsystem - 2025.2 English - UG1483

You can create a variant subsystem by dragging a Variant Subsystem block from the Library Browser into your model. This block then contains underlying blocks to implement each variant. To create a variant subsystem, do the following:

1. Drag a Variant Subsystem block into your model. (You can find the Variant Subsystem block in the Simulink Library Browser. Navigate to Simulink > Ports & Subsystems > Variant Subsystem.)
   
   
2. Double-click the Variant Subsystem block.
   
   
3. Each variant choice is defined in a Subsystem or Model block within the Variant Subsystem. You can define each variant choice's implementation by populating the Subsystem blocks in the model, or by copying Subsystem or Model blocks from elsewhere. Rename each Subsystem block to describe which variant selection it represents.
   Note: Do not connect the Variant Subsystem block inputs and outputs; the port connectivity is determined at runtime based on which variant is active.