Patent ID: 9405278
Filing Date: 2016-08-02
CPC Classification: G05B

Claim Text:
1. A method for operating a safety control device for safely controlling a hazardous installation having at least one actuator, the method comprising the steps of: providing a first calculation unit and providing a second calculation unit in the safety control device in order to form a redundant control unit, acquiring an input signal and feeding the input signal to the first and second calculation units, determining a floating point value depending on the input signal in each of the first and second calculation units, determining an input interval as a function of the floating point value in each of the first and second calculation units, determining a plurality of result intervals, wherein the first and second calculation units each determine a result interval as a function of the input interval by applying a first calculation algorithm to the input interval, the first calculation algorithm being based on interval arithmetic, comparing the result intervals from the first and second calculation units and determining an output value as a function of the result intervals, and outputting an output signal as a function of the output value, said output signal driving the at least one actuator.