Siemens Industry Online Support
Siemens AG
Entry type: Application example Entry ID: 24000238, Entry date: 12/01/2011

PROFINET IO – Diagnostics Processing in the User Program

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The distribution of distributed automation systems with PROFINET also increases the significance of monitoring and diagnosing such systems. STEP 7 offers a number of internal system functions for diagnosing PROFINET IO devices. This application uses two different approaches to show the implementation of this task within the STEP 7 user program and the display on a SIMATIC HMI system.

The figure below shows the hardware configuration used for the solutions:

The following two solution principles were realized as examples:

  • Sample solution with SFC 51 (RDSYSST reading out an SSL partial list) and SFB 54 (RALARM) - receiving an interrupt

  • Sample solution with the diagnostics expansion (FB_126_Dataset) based on "Report System Error".

The sample solution with SFC 51 and SFB 54 describes a status or diagnostics evaluation in the startup OB (OB100/101) or in the diagnostic organization blocks (OB82/83/85/86). The sample solution shows you the respectively required STEP 7 program. The static diagnostic information is visualized on a SIMATIC HMI panel on an individual diagnostics user interface with WinCC flexible.

In contrast, the sample solution with the diagnostics expansion (FB_126_Dataset) based on "Report System Error" only requires a minimum of its own user program. The diagnostic functions are generated by the configuration in STEP 7 and can be applied with minimum programming effort. The sample solution shows you how to query the diagnostic data using the "Report System Error" functions in the control program. The diagnostic information is again visualized on the SIMATIC HMI panel.


Content of Downloads


PROFINET IO – Diagnostics Processing in the User Program
24000238_PROFINET_IO_Diag_V10_e.pdf ( 2479 KB )
24000238_SZL-Listen_Extract_V10_en.pdf ( 547 KB )
Code (Software)
The ZIP file contains the archives of the described sample solutions.
24000238_PROFINET_IO_Diag_CODE_V10.zip ( 5455 KB )

Additional Information
In connection with this application, an additional document dealing with PROFINET IO diagnostics in STEP 7 is available.



PROFINET IO - Configuration & Diagnostics Entry-ID: 22981197

Security Notice
The functions and solutions described in this article confine themselves to the realization of the automation task predominantly. Please take into account furthermore that corresponding protective measures have to be taken up in the context of Industrial Security when connecting your equipment to other parts of the plant, the enterprise network or the Internet. Further information can be found under the Entry-ID 50203404.

Last Changes
Implementation of the document "SSL-Lists with PROFINET/ PROFIBUS"


Security information
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