1756-RM001B-EN-P, Using ControlLogix in SIL2 ... - Tuv-fs.com

Technical SIL2 Requirements for the Application Program 9-3SpecificationThe specification must include a detailed description that includes (ifapplicable):• Sequence of operations• Flow and timing diagrams• Sequence charts• Program description• Program print out• Verbal descriptions of the steps with step conditions andactuators to be controlled, including:– input definitions– output definitions– I/O wiring diagrams and references– theory of operation• Matrix- or table form of stepped conditions and the actuators tobe controlled, including the sequence and timing diagrams• Definition of marginal conditions, for example, operatingmodes, EMERGENCY STOP etc.The I/O-portion of the specification must contain the analysis of fieldcircuits, that is, the type of sensors and actuators:Sensors (Digital or Analog)• Signal in standard operation (dormant current principle fordigital sensors, sensors OFF means no signal)• Determination of redundancies required for SIL levels• Discrepancy monitoring and visualization, including the user’sdiagnostic logicPublication 1756-RM001B-EN-P - October 2003