Patent ID: 7948391

Claim:
A safety switching device for use in a safety circuit having a safety controller configured to interrupt the supply of power to an installation in a failsafe manner in response to receipt of an output signal from the safety switching device, the safety switching device comprising: a device housing having a plurality of terminals accessible on the outside of said housing including a first input terminal for receiving a fixed operating voltage and first and second output terminals for redundantly producing said output signal, the device housing accommodating: an input part for monitoring a current state of an actuator or a signaling device having at least two different states and for generating a first signal in response to a change in the current state of the actuator or signaling device, first and second switching elements each having an input and an output, wherein the outputs of the first and second switching elements are connected respectively to said first and second output terminals, and a control part connected to the input part and the first and second switching elements for controlling said first and second switching elements to redundantly generate said output signal in response to said first signal from said input part; wherein the input of each of said first and second switching elements is connected internally within the device housing to said first input terminal for receiving the fixed operating voltage; and further wherein said safety switching device further comprises a third output terminal connected internally within said device housing directly to said first input terminal for supplying said fixed operating voltage in an unswitched manner directly to said third output terminal.