I am trying to do the exact same thing, but I can't get it to work and not sure why or what's not happening or what's happening that won't let it work.  I have a comfort panel and just want to log values when I trigger a bit.

I've done the following:

1. Set up your data logs in historical data with logging method "trigger event".

2. Still in historical data, set up your logging modes with your acquisition mode "On Demand"

3. Go to the HMI tags and look for the tag you want to use to trigger logging. Click on it and go to properties -> Events. With event "Value change" add the function "startlogging" and point it to the log that you entered in step 1

4. Now add a "logTag" function and select the tag you want to log (should correspond to the log tag in step 2.

5. add the function "stoplogging" and point it to the log that you entered in step 1.

But nothing happens.  On my trigger tag, I made the events, and then after the stoplogging event I put a reset bit to reset the trigger so the PLC knows it's done, but that bit doesn't get reset, and no data log is created.  Any suggestions?  Does anyone know how I can troubleshoot this since it just does nothing for me?  

Also what is the point of having the log setup in multiple locations?  so I can make logging tags in the tag editor, and they get transferred to the historical data log portion?  Or do i have to enter it there?  why is it in multiple spots its very confusing.  

I would like to simply pick 5 tags that I want logged, and a trigger tag to log it.  I want it to log the 5 tags when the trigger tag goes high then reset the trigger tag.  Extremely simple in my experience, but this is not simple on Siemens.  

Any help or resources is appreciated. 

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Split from Trigger Data Logging from PLC on HMI.

Hi,

Attached is quick setup of trigger logging.

It is not indetail, but point is that you do not usually need to stop logging during operation unless your trigger tag value changes when you do not want to log values. So do not start and stop on every value logging. (I do not know if you do that, just a point)

Or you are creating a batch report and need the log file of that cycle. Then you probably would use OpenAllLogs and CloseAllLogs too.

EDIT: If you do have a need to start and stop logging. Wait a while or use system events after starting before looging values.

What I want to do is create a log file like the picture shown (and attached).

I want it to be a .csv file, and I really want comas, not semi-colons.

I want to trigger a bit, have one line of data appended to the file, and I want that bit reset - or another bit turned on so the PLC knows it's done.  I don't even care about the handshake, even if it just turns off the trigger bit that is enough.  And there has to be some way to turn that bit off without triggering another changed event.    

Is that possible in comfort panel?  

In the past, I would tell the device the trigger bit, the data to log, the header names for the log, and a handshake bit.  Is there a way to make that happen with WinCC and comfort panel?

I don't do siemens much so it's not worth my time to figure out how to do it in a VB script and all of the other things that could be done to make this work. 

Went through the PDF and I don't understand what's different about what I'm doing than what it says on there. 

Can anyone explain why I would "start logging" and leave it started when I only want one line of data every 30 seconds or so?  What does it mean when it says "you can leave it open if the log is not needed elsewhere"  What does that mean needed elsewhere?  I want to have other logs that do basically the same thing, so does that mean it is needed elsewhere?  

Log has always the same structure. One tag on line below is the header. If you log five tags there are lines.

VarName "TimeString" "VarValue" "Validity" "Time_ms"

You will have commas if Comfort panel regional settings is set to use comma as list separator. 

I think that if you want to know when logging is done you have to stop logging after each line and use the system function i mentioned to reset that bit.

I would really consider using VB script for logging. It is only few lines of code and setting or resetting some bit after script has executed s really simple. Also you will get the file structure you want.

Logging with WinCC keeping the file open is simpler than opening and closing it every time(with cyclic logging this is also necessary). Logging with trigger tag and programming with e.g. C# I would open and close file every time. And if logging with VB script in WinCC this would also be the case.

But I think that winCC opens the log asynchronously, so you cannot log with same tag without delay or handshake of some kind.

I mentioned use of system events, but just noticed that Start of log event does not have events of its own, so you cannot use that for logging.

When you start logging system just opens the file and  is ready to log. Like opening any document with any tool.

If you need it elsewhere means that if you e.g. open and edit it with some tool. You can open it in read only because it is open I WinCC. 

No it does not mean that it is needed elsewhere, it is different document.

MikeD43

Went through the PDF and I don't understand what's different about what I'm doing than what it says on there. 

Can anyone explain why I would "start logging" and leave it started when I only want one line of data every 30 seconds or so?  What does it mean when it says "you can leave it open if the log is not needed elsewhere"  What does that mean needed elsewhere?  I want to have other logs that do basically the same thing, so does that mean it is needed elsewhere?  

3 times the cost for the HMI, and 3 times the work?  That doesn't quite make sense...

I tried the code you posted and it doesn't get past the first  CreateObject("FileCtl.FileSystem").

Wish there was some reference material for VB scripting in here or a debug feature, at this point, it doesn't work at all.  Sweet. 

 What is? And what does not?

MikeD43

3 times the cost for the HMI, and 3 times the work?  That doesn't quite make sense...

Tried the stuff you posted for the VB script and it just does nothing.  I put some integers in to see where the error was stopping the script, and it didn't get past the first Set fs = createobject("filectl.filesystem")   

No idea why or what it is supposed to be.  After triggering this, the vbScriptStep goes from 0 to 1.  And yes I'm assuming since I'm simulating on my laptop that it can find the C drive and the path to the desktop.