Acqusition cycle of 100 ms Tag Logging WinCC 7.5

Good day everyone,

I have some data that I need to log every 100 ms, but the minimum Acquisition Cycle and Archiving/Display Cycle is 500 ms in WinCC 7.5. Is there any way to store these tags every 100 ms?

I read about AR_SEND block, but that's only for CPU 400 (mine is 1517), and I have not seen that function in this CPU.

In case it's not possible, I could make a function in the PLC to store that data every 100 ms with a Cyclic Interrupt OB and store that data in a SQL table using a global script in WinCC. However, could I later see that data in a WinCC Trend somehow, or would that not be possible, since it would not be stored as raw data (or the same encrypted format as Tag Logging does) nor in the same exact table as the "normal" tags stored with Tag Logging?

Thanks,

Mikel

Hi MikeApp

The is no possibility to modify the cycle in your wincc to 100 ms. 

Best regards

schufri

Hello Georg,

Thanks for your answer. I'll take a look at this function to make it work. I have some questions, though:

- Do I need a special license to use ODK functions? In case it's affirmative, could you tell me, please, which one?

- The system can convert internally the timestamp to the date format it uses so it can be correctly displayed in a WinCC Online Trend Control? Or should I do some other function to convert it to some other format as well?

- Do I need to indicate the exact DataBase to write the data? I ask this because I know WinCC creates different DataBases to archive Tag Logging and Alarm Logging data and I am not sure how could I know the exact DataBase to write (since the internal tag @DatasourceNameRT only indicates the Runtime Database).

 Regards,

Mikel

Good day,

I have a question regarding the parameter dwFlags. I have read that setting its value to 0x00000001 (TLG_API_FLG_FAST_INSERT) really improves the speed of introducing data, but it can "destroy" already stored values in case that some previous data is stored later (for example, you store something from today at 10 AM but there's data already stored from 11 AM). In my case, I will do it with a FIFO system in the PLC so this should not be a problem. However, I am not sure if the tag that I want to store in the Tag Logging should have something in "Acquisition type" column (for example Cyclical, continuous with 1 minute, for example). I understand that, should something happen, data could be lost. I meanm if there could be problems because data will be saved from the PLC and from SCADA with the Tag Logging, depending on the Acquisition type.

So, is it TLG_API_FLG_FAST_INSERT worth using it? And if that's the case, what securities could be implemented in the Tag Logging for that signal?

Regards,

Mikel

Hello Georg,

Thanks for your answer.

What do you mean is not relevant? I asked that thinking that (having in mind that I would have the timestamp of the data stored in the FIFO in the PLC), if there was some kind of error at some point that makes the code be executed later, but there's some kind of Acquisition type (for example, every minute) and WinCC Tag Logging registers newer data before the code stores the older data in the FIFO, that could be a problem if dwflags =  0x00000001. That's why I asked that (I don't know if it's possible to have an Acqusition type as acyclic without an Start tag defined, so it can be assured that that signal will only be stored with the function "TLGInsertArchivData", for example).

Also, if I understood correctly, "CCWriteArchiveServer.exe" is only necessary to be executed if dwflags =  0x00000000, am I right? I guess that this program should be executed from the same C-script after calling the function "TLGInsertArchivData", right?

Regards,

Mikel

After some days, I have made the FIFO and the C-Script in WinCC. The FIFO is working nicely, but I have a problem with the script. When I call the function TLGInsertArchiveData I get an error, but when I comment that function, the rest of the code works correctly.

My guess is that some parameters that I pass to that function are not correct, but I'm not sure about that.

I have attached the code I used (code.txt), an image of the output I get (output.jpg) with an example without TLGInsertArchiveData (so there's no error) and another calling that function (with the error). In the output can be seen the parameters I pass to the function, too.

I have also attached ArchivName.jpg and VarName.jpg where my Tag Logging configuration can be found with the signal I am trying to save (for VarName, I have tried both "Process Tag" and "Tag Name", but with the same result). Also, I have attached SQL_Archive.jpg, where it can be seen the signal I want to save in the SQL Table "Archive", where its "ValueName" can be seen.

Does anybody have any idea where the error could be?

PS: In the end I pass the date and time from the PLC as separated parameters, since I lost the milliseconds as TimeStamp (which is crucial to have in this case).

Thanks,

Mikel