Safety-related control unit and method for controlling an automated installation

摘要

A safety-related control unit for controlling an automated installation in accordance with an application program containing control instructions. The safety-related control unit has first and second processors for executing at least some of the control instructions by processing a plurality of first and second program variables, respectively. The first processor also determines a first test value for at least one of the first program variables in accordance with an instantaneous value present for this first program variable at a first defined instance of time. The second processor determines a second test value for the at least one of the first program variables. The second test value corresponds to the first test value. The safety-related control unit also has a data memory for storing the instantaneous value, the first test value and the second test value in order to facilitate a quick restart of the control unit after an unexpected interrupt.

主权项

1. A safety-related control unit for controlling an automated installation in accordance with an application program executed on the control unit, the installation comprising a plurality of sensors and a plurality of actuators, and the application program comprising a plurality of control instructions for controlling the actuators, the safety-related control unit comprising:
a first processor for executing at least some of the control instructions by processing a plurality of first program variables, the first processor also determining a first test value for at least one of the first program variables in accordance with an instantaneous value present for said at least one of the first program variables at a first defined instance of time, a second processor for executing at least some of the control instructions by processing a plurality of second program variables, the second processor further determining a second test value for the at least one of the first program variables, said second test value corresponding to the first test value, and a data memory designed for storing the instantaneous value, the first test value and the second test value; wherein the safety-related control unit is configured to perform a validity check of the instantaneous value at any restart by using the first processor and the second processor, wherein the first processor performs the validity check of the instantaneous value using the first test value, and wherein the second processor performs the validity check of the instantaneous value using the second test value.