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Entry type: Application example Entry ID: 109482621, Entry date: 05/23/2016

Efficient engineering of interlocking with PCS 7 Logic Matrix

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The application example describes the creation and visualization of interlocking using the PCS 7 Logic Matrix. It provides step-by-step instructions and an example project to demonstrate the visualization and the functionalities.

The basic automation tasks in process automation involve the creation of logic operations. The main tasks of the logic operations are:

  • Permission
  • Protect
  • Interlocking 

Typical interlocking functions include stopping a pump with a closed valve or preventing a mixer from starting if the minimum fill level is not reached. Other reasons for interlocking can be, for example, high temperature or pressure.
Using the example of a stirred tank reactor the typical interlocking functions should be created. A fundamental requirment is to create the interlocking function in such a way that in case of interlocking, the operator can find and resolve the cause quickly.

You can use the PCS 7 Logic Matrix to implement the automation task.

The PCS 7 Logic Matrix is a tool for creating and visualizing interlocking with up to 125 causes and up to 125 effects. A cause reprecents a logical with up to six inputs (three analog abd three digital), whose results is good or bad, and whose effect can be transmitted via so-called nodes (intersections) to effects with one or more outputs. This allows each cause to act on each effect or even on just a part of the effects.

The application example describes the creating of the interlocking function with the Logic Matrix Editor as well as the operation and the function of the Logic Matrix Viewer on the OS. The example project contains all described components and can be used for demonstration purposses or to the selfstudy. 

The creation of interlocking with PCS 7 Logic Matrix offers the following benefits:

  • Clear display of interlocking using the Logic Matrix Editor according to the causes and effects principle
  • Simple modification and optimization of interlocking
  • More efficiency compared to the "standard" interlock at CFC level
  • Cleare representation of interlocking in the OS runtime
  • Filter options for rapid location of the interlocking cause within the OS runtime
  • Time and cost savings in engineering and operation


Documentation and demo project
  Documentation "Efficient engineering of interlocking with PCS 7 Logic Matrix" (2,8 MB)
 Registrierung notwendig  Project "Efficient engineering of interlocking with PCS 7 Logic Matrix" (98,1 MB)

Further informationen
Manual "SIMATIC Process Control System PCS 7 Logic Matrix"

Additional keywords
Matrix, demo project, interlocking, interlocking funktions, logic operations

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