Method for operating a safety control device

摘要

A safety control device for safely controlling a hazardous installation has a first and a second calculation unit and an output unit for driving at least one actuator. The control device acquires an input signal and determines a floating point value depending on the input signal. The first and second calculation units each determine an input interval as a function of the floating point value. The first and second calculation units each further 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 is based on interval arithmetic. The result intervals from the first and second calculation units are compared and an output value is determined as a function of the result intervals. An output signal is determined as a function of the output value. The output signal drives the at least one actuator.

主权项

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.