Introduction to Simulink with Engineering Applications

The Terminator block can be used to cap blocks whose output ports are not connected to other blocks. If we run a simulation with blocks having unconnected output ports, Simulink issues warning messages. We use Terminator blocks to cap those blocks to avoid warning messages.
Let us consider the unconnected output of the Sum block in Figure 2.7.
Figure 2.8 shows the Sum block output connected to a Terminator block.