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Entry type: Application example Entry ID: 58793869, Entry date: 12/05/2017

Sequential Muting of a Light Curtain with S7-1500

  • Entry
  • Associated product(s)
Access to the assembly cell is to be protected with a safety light curtain. The objective is to detect in case of a violation of the detection zone (interruption of light curtain) if a workpiece is transported through the light curtain or if it was interrupted by another object.

So-called “muting” is used to distinguish if the protective field is violated by the transport of workpieces or by other reasons. Muting is the intentional suppression of the protective function of light curtains
- the light curtain is “muted” temporarily. For this purpose, muting sensors are installed on both sides of the light curtain which determine in which cases to activate muting. This allows transporting workpieces out of the work area without interrupting the production flow and at the same time monitoring access to the hazard area.

Figure 1

Figure 2 schematically shows the most important components of the application example:

  • SIMATIC F-CPU (IO controller)
  • Distributed I/O SIMATIC ET 200SP (IO device) with DI, DQ, F-DI, F-DQ
  • SICK safety light curtain
  • SICK photoelectric retro-reflective sensors as muting sensors

Figure 2

Sequential muting with 4 muting sensors (2 sensor pairs) is implemented in the application example. Photoelectric retro-reflective sensors are used as muting sensors.

Documentation and example project
  Documentation (1,3 MB)
 Registrierung notwendig  Example project for TIA Portal V13 SP1 (18,3 MB)
 Registrierung notwendig  Library "LMutS" V2.0.1 for TIA Portal V13 SP1 (1,4 MB)
 Registrierung notwendig  Evaluation of the safety functions as SET project (11,7 KB)

Last Changes
Bug fix on output "freeReq"

Additional Keywords
Safety Advanced, light curtain

Security information
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