Connecting switch to a resistor in Simulink
you are attempting to connect a SimPowerSystems domain node to a Simulink domain node... 

The switch you are using is for simulink signals NOT electrical signals. 

For simPowerSystems there is an IdealSwitch which takes a Simulink-domain control signal. This only open-circuits a signal signal &amp; does not act as a double-throw switch. Linking two together &amp; using a logic NOT on one would provide the same affect

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