Patent ID: 8363371

Claim:
A safety switching device ( 900 ) for setting at least one safety-related device into a safe state, the device comprising: a first connection device ( 910 ) for connecting the safety switching device to a single-phase or multiple-phase power supply device; at least one second connection device ( 920 ) for connecting a safety-related device; a third connection device ( 940 , 945 ) for connecting at least one safety-related input stage ( 760 ); a power amplifier ( 200 ) that is single-phase or multiple-phase connected between the first and second connection devices ( 910 , 920 ) with at least one controllable switch contact; a measurement device ( 610 ); and a safety device ( 820 , 840 ) for multiple-channel driving of the power amplifier ( 200 ); wherein the safety device ( 820 , 840 ) comprises a first control device ( 820 ), which has a programmable control unit ( 822 ) and which has a device for generating a monitoring signal, and a second control device ( 840 ), wherein the input stage ( 760 ) is connected to the first control device ( 820 ) and to the second control device ( 840 ) and is constructed for modulating an input signal with the monitoring signal coming from the first control device ( 820 ), wherein the first control device ( 820 ) and/or the second control device ( 840 ) set the safety-related device into a predetermined safe state in response to the modulated input signal, if a fault occurs, and wherein the first control device ( 820 ) is allocated to the measurement device ( 610 ) and is constructed such that it sets the safety-related device into a predetermined safe state via the power amplifier ( 200 ) as a response to a measured analog signal, if a predetermined parameter of the measured analog signal lies outside a predetermined operating range.