WinCC Flex Panel (MP277) to database?

[cjd1965]

Hi I have a requirment to track barcodes and date stamps of said barcodes.

It is unclear how many need to be logged but I would say 2000 rows would cover it. As I see it this would be better in some kind of database but the SQL for the Panel weems non existent

I could use a long DB but I think I would be oversize

Any suggestions welcome

 

[JesperMP]

I was thinking maybe recipes could do it, but the MP277 is limited to 300 recipes, and a PC RT is limited to 999 recipes.

Maybe you should ignore the MP277 and establish a more direct connection between the PLC and the database.

 

[cjd1965]

OK thanks Jesper

 

[uptown47]

I would have thought that 2000 would be fine in a couple of DBs. One to track the code and another to track the timestamp. I know it would be a bit unwieldy but I think it should work.

 

[JesperMP]

It depends on how long the barcode is.
Also depends on if it is purely a number, or of there are characters as well.
If it can fit in a DINT, then no problem.
If it is 20 characters for example, then it will cost 44kB, which may or may not be a problem.

 

[cjd1965]

Hi
I am going off the DB idea... as I understand a power cycle will default the data values. I am trying to persuade my client to use their existing SCADA to log my data. This would be some much a better solution but they dont have a budget in place for third party to revise the SCADA.

Alternatively I am considering text files on the HMI. One per barcode/date. I will simply create a file name of barcode_ddmmyy_hhmmss.txt and if i detect a matching barcode, delete then save the new one.

 

[uptown47]

A power cycle won't default the data values of the DB's. They are retentive.

Using SCADA and maybe saving them to an Excel file or text file would probably be better though ;-)

 

[cjd1965]

A power cycle won't default the data values of the DB's. They are retentive.

I thought that was the purpose of Ram to Rom on the MMC PLCs?

 

[uptown47]

I thought that was the purpose of Ram to Rom on the MMC PLCs?

Not 100% sure what you mean by that. But, if you have values in your DBs they will still be there after you turn the PLC off and on again.

If you were to copy from ROM to RAM then you may re-initialise the DB's. (I'm not sure).

Also, if you chose to re-initialise the DBs via Simatic Manager it would over-write them with the initial values.

;-))

 

[JesperMP]

Copy-RAM-to-ROM copies the actual values to the flash card. This is the way to make certain that the actual values stay even after a longer shut-down period.
There is also a possibility to use SFC84 to write the DB content to the flashcard during runtime. You can trigger this by a button on the HMI for example.

Anyway, I am thinking, that if all this is merely about logging of scanned barcodes, then it would be fairly easy with a VBS script to write the barcodes to a .txt or .csv file on a memory card. That will cost next to nothing, only the logfile will be on the memory card, not in the database.

 

[cjd1965]

Thanks for clearing that up Jesper.

Is the vbs script valid for panels too? I guess it is because that is in the title of the thread.

I agree this will be easiest and need to read into it. I am thinking about reading in a csv file, amending the relevant row, and writing it back again.

 

[JesperMP]

Yes, you can write VBS scripts that writes to files on CE panels.
The code that accesses the file system is slightly different to the same code on a regular Windows system.

 

[cjd1965]

Hi Jesper
I have looked into this a little with Siemens 16502685 but it seems that i cannot use this on my laptop pc runtime due to vbs vs vb. Is there a solution other than buying a MP277?

Seems a bit **** for development if you cannot simulate a panel...

Thanks

 

[JesperMP]

Well you have to buy the panel anyway. Get it now and do your testing. Then install it in the control panel when you are done.

 

[cjd1965]

Well you have to buy the panel anyway

While I agree it is dissapointing to not be able to develop and test within the simulation facilities.

Thanks for your time on this thread