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Entry type: FAQ Entry ID: 16532187, Entry date: 11/15/2006

Where can you find descriptions and examples of PID control with FB 41, FB 42 and FB 43, and SFB 41, SFB 42 and SFB 43?

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  • Associated product(s)

The PID Control control functions CONT_C, CONT_S and PULSEGEN are available in two versions but with identical functions:

  • FB 41, FB 42, FB 43
    The loadable controller FBs are regular user blocks that run in all CPUs (S7-300, S7-400).
  • SFB 41, SFB 42, SFB 43
    The controller SFBs that are integrated in the operating system are in all S7-300 CPUs of the types 313C and 314C and in the C7 devices.

Descriptions of the above controller functions are available in the following documentation:

  • Reference manual "System Software for S7-300/400 System and Standard Functions)", Volume 2, Chapter 27 (Entry ID: 1214574);

  • Manual "S7-300 Automation System CPU 31xC Technological Functions" (Entry ID: 12429336). Examples of the SFBs are available for downloading as a self-extracting file under the "Info" link of the entry.

  • Manual "SIMATIC Basic Software for S7-300/400 PID Control" (available by calling "STEP 7 - PID Control" in STEP 7 under "Start > SIMATIC > Documentation > ...").

  • Online Help of the block concerned.

1 ) The document can also be called as "STEP 7 - System Software for S7-300/400 System and Standard Functions" in STEP 7 under "Start > SIMATIC > Documentation > ...".

The controller blocks themselves are available in the STEP 7 Standard Library (SIMATIC Manager: "File > Open > Libraries > ...") in the "PID Control Blocks" (FBs) folder or "System Function Blocks" (SFBs) folder.

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