Rockwell Automation 21G PowerFlex 750-Series AC Drives Reference Manual - Manual (Page 125)

Rockwell Automation Publication 750-RM001F-EN-P - February 2012 125
Safety Configuration and Verification Chapter 10
Specifying the Safety Configuration
You must create a specification for the system configuration that addresses the
safety requirements identified by a risk assessment of your application. Use the
specification to verify that the configuration is selected correctly and that it fully
addresses your application’s functional and safety control requirements. The
specification must be a detailed description that may include (if applicable):
• a sequence of operations.
• flow and timing diagrams.
• sequence charts.
• a configuration description of each parameter.
• documented descriptions of the steps with step conditions and actuators to
be controlled.
• input and output definitions.
• I/O wiring diagrams and references.
• a theory of operation.
• a matrix or table of stepped conditions and the actuators to be controlled,
including sequence and timing diagrams.
• a definition of marginal conditions, for example, operating modes.
The I/O portion of the specification must contain the analysis of field circuits,
that is, the type of sensors and actuators.
• Sensors (Digital or Analog)
– Signal in standard operation (dormant current principle for digital
sensors, sensors OFF means no signal)
– Determination of redundancies required for SIL levels
– Discrepancy monitoring and visualization, including your diagnostic
logic
• Actuators
– Position and activation in standard operation (normally OFF)
– Safe reaction/positioning when switching OFF or power failure.
– Discrepancy monitoring and visualization, including your diagnostic
logic.