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Entry type: FAQ Entry ID: 16622456, Entry date: 04/09/2019

What do the entries in the WinCC diagnostics file "SIMATIC_S7_PROTOCOL_SUITE_01.LOG" mean in the case of a connection fault?

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In the event of a fault in the connection for the "SIMATIC S7 PROTOCOL SUITE", error codes are created in hexadecimal format in the file "SIMATIC_S7_PROTOCOL_SUITE_xx.LOG".

The "SIMATIC_S7_PROTOCOL_SUITE_xx.LOG" file is located in the Installation path of WinCC, for example: "C:\Programs(x86)\Siemens\WinCC\Diagnostics".

An entry in this diagnostics file looks like this, for example:
2009-06-17 09:13:17,813 ERROR Cannot connect to "verb_S7MPI_2": Error code 0xFFDF 42C2

The hexadecimal number 42C2 is the actual error code. An explanation is available in the Help file "S7Chnerrrordeu.chm" for German and in the Help file "S7Chnerrorenu.chm" for English with the error codes directly in the WinCC installation path; for example: "C:\Programme(x86)\Siemens\WinCC\bin".
Use the search function in this help file to get the explanation of the corresponding error code.
More error codes with brief error descriptions are available in the section "s7chnerrorenu.doc".

The descriptions below relate to some error codes which cannot be found directly in the WinCC Online Help under the link indicated above.

Error code Description Remedy
Error 8304 The error code indicates connection problems between WinCC and the S7 controller. The effect can be, for example, that the picture currently in WinCC Runtime may no longer be refreshed. Disable the cyclic read services of the automation system (AS). Information about this is available in Entry ID 22558461 .
Error D801 There is at least one variable for this connection with invalid address details. Check the address details of all the variables. Make sure that the data blocks are stored in the S7 and are long enough.
Table 01

Additional Keywords
Communication fault, Error message, 22556102

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