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Entry type: Application example Entry ID: 81304594, Entry date: 10/21/2013

SINUMERIK 840D sl Safety functions: Calculation examples for safety functions at horizontal axes

  • Entry
  • Associated product(s)

This application example explains how to calculate the Performance Level for safety functions based on the EN ISO 13849-1 standard.

The following cases are taken into consideration:

  • Stopping a horizontal axis for an Emergency Stop (safe standstill)
  • Preventing a horizontal axis from unexpectedly starting when the protective doors are open (safe operating stop)
  • Traversing a horizontal axis with acknowledgment button and safe velocity
  • Safely shutting down modules for an Emergency Stop, open protective doors and actuating the acknowledgment button
  • Operating mode selection
  • Start and restart function after an interruption (e.g. NC start)
  • Re-establishing the power feed after an interruption (e.g. machine "on")
  • Evaluation of safety-relevant feedback signals (e.g. safe output cams)
  • Evaluation of "non-safety relevant (standard) signals

For all of the examples, it is assumed that a SINUMERIK 840D sl is used with Safety Integrated.
Only one drive is assumed when calculating the safety functions.
If more than one drive is involved in the safety function, then these additional drives must also be appropriately incorporated in the calculation.
You can find detailed calculations for the individual safety functions in the SET and SISTEMA files.

You can find calculations for safety functions for axes subject to the force of gravity under entry id: 72850017


Content of Downloads


Documentation 81304594_Safety_functions_for_horizontal_axes_DOKU_V10.pdf ( 342 KB )
Calculation example (SET and SISTEMA files) 81304594_en.zip ( 247 KB )

Last Changes
10/2013, first publication

Additional Keywords
motioncontrol_cnc_applications, SI-Funktionen, SI Functions

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