A safety system for multi-channel monitoring of a safety-related device, the safety system comprising the following features: at least first and second logic devices (101, 102), wherein each of which is associated to a separate channel and to be protected against faulty logic voltages: - an input terminal for supplying an input voltage; - a controllable switching element for passing the input voltage to the first and second logic devices (101, 102) or blocking the input voltage from the first and second logic devices (101, 102); - a first DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the DC voltage converter, wherein the first DC voltage converter provides as an output voltage a first logic voltage to the first logic device; - at least one second DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the voltage converter, wherein the at least one second DC voltage converter provides as an output voltage a second logic voltage to the second logic device; and - a first monitoring device for redundantly monitoring the first and second logic voltages, wherein the first monitoring device comprises a comparator which is supplied with the first and second logic voltages and a reference voltage, so that the first monitoring device drives a holding means for opening and reliably holding the switching element in the open state, if at least one of the first and second logic voltages reaches or exceeds a predetermined threshold voltage value. at least first and second logic devices (101, 102), wherein each of which is associated to a separate channel and to be protected against faulty logic voltages: - an input terminal for supplying an input voltage; - a controllable switching element for passing the input voltage to the first and second logic devices (101, 102) or blocking the input voltage from the first and second logic devices (101, 102); - a first DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the DC voltage converter, wherein the first DC voltage converter provides as an output voltage a first logic voltage to the first logic device; - at least one second DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the voltage converter, wherein the at least one second DC voltage converter provides as an output voltage a second logic voltage to the second logic device; and - a first monitoring device for redundantly monitoring the first and second logic voltages, wherein the first monitoring device comprises a comparator which is supplied with the first and second logic voltages and a reference voltage, so that the first monitoring device drives a holding means for opening and reliably holding the switching element in the open state, if at least one of the first and second logic voltages reaches or exceeds a predetermined threshold voltage value. - an input terminal for supplying an input voltage; - a controllable switching element for passing the input voltage to the first and second logic devices (101, 102) or blocking the input voltage from the first and second logic devices (101, 102); - a first DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the DC voltage converter, wherein the first DC voltage converter provides as an output voltage a first logic voltage to the first logic device; - at least one second DC voltage converter having an integrated voltage monitoring device, which monitors the output voltage from the voltage converter, wherein the at least one second DC voltage converter provides as an output voltage a second logic voltage to the second logic device; and - a first monitoring device for redundantly monitoring the first and second logic voltages, wherein the first monitoring device comprises a comparator which is supplied with the first and second logic voltages and a reference voltage, so that the first monitoring device drives a holding means for opening and reliably holding the switching element in the open state, if at least one of the first and second logic voltages reaches or exceeds a predetermined threshold voltage value.