A switching device includes: a triggering unit; an actuator coupled to the triggering unit; a switching mechanism coupled to the actuator; and an interface module. The interface module includes: a signal processing unit coupled to the triggering unit; an interface circuit coupled to a transmitting and receiving circuit of the signal processing unit; a power supply input for feeding a first supply voltage; and a voltage converter connected on an input side to the power supply input and a power outlet for issuing a second supply voltage. The power outlet is coupled to the signal processing unit and to the triggering unit.