Creating .txt files in PLC and FTP-server access

[Gimbel]

I'm currently looking into the possibilities for using a PLC as a counter module (production counters) and to afterwards create a .csv/.txt file which has to be send to an FTP server. The file only needs to be uploaded to the FTP server once a day and will only contain very limit amounts of data.

I figured that a PLC could be of interest as the counted values should be shown on a big LCD display. The max. counting frequency would be approx 600pcs/min.

Does anybody have experience with such task and would it be something which is durable in an AB PLC (as this is the preferred brand of the customer) or must I simply go in another direction using other kinds of hardware

Kind regards

/Gimbel

 

[JesperMP]

Hej Gimbel.

I think that many SCADAs can do what you want. Might take some scripting to get it done.

Sending files to an FTP server directly from the PLC is another matter. There are a few PLCs that can do it.

Beckhoff:
http://beckhoff.de/english/twincat/twincat_ftp_client.htm?id=51106840184

Siemens:
http://www.automation.siemens.com/n...pdf/ethernet/qscd_08_cp343-1_fb40_usage_g.pdf

Dont know about other PLC brands.

Disclaimer - I have zero experience with the above mentioned FTP methods.

 

[JesperMP]

Maybe using FTP is a too crude method for what you really have to achieve.
If you need to log production data, then there are many ways to log the values to either databases or into simple CSV files.

Try to describe what you actually need to achieve.

 

[Gimbel]

Hi JesperMP,

What I have to do is to apply this new counting functionality to a existing production line, but i'm not allowed to integrate it with the existing control system at all. The new counting system is to be totally separated.

The requirement to have the data delivered to an FTP server could be to provide these data to a production management system, maybe for SAP, production databases etc via the FTP-server. This means that by delivering the data in a textfile the data will be easily modified into another required format for the subsequent processes to be able to utilize the data.

I am for now looking at the modules webport 2001 and Webport 4001 from Spectrum Controls (spectrumcontrols.com) in order to see whether they could provide the required interface to the FTP server.

/Gimbel

 

[JesperMP]

If the requirement is that the data must arrive in a text file, then I think that to have the data sent to an FTP server may be unnecessary cumbersome.
Is it because the data has to be sent somewhere out of house wia the internet ?

How do these webport devices get the data to send ?

 

[hd_coop]

We installed a Webport several years ago. It was replaced in less than 6 months by a Red Lion Data Station Plus. The Red Lion is much easier to program. It creates log files which are stored on its internal compact flash card accessible via web browser. These log files can be automatically copied to an FTP server, or via a program running on a PC be copied to a hard drive.

 

[Gimbel]

If the requirement is that the data must arrive in a text file, then I think that to have the data sent to an FTP server may be unnecessary cumbersome.
Is it because the data has to be sent somewhere out of house wia the internet ?

How do these webport devices get the data to send ?

The requirement for the moment is that the data arrive in a text file named from time/date/unit etc. to make it unique the content of the textfile must also have a certain format. As I have understood the task the textfile must be accessible from multiple sites and thus the customer has specified that they want to have the file on a ftp-server.

How the webport acquires the data I do not know yet as I actually do not know whether it can solve the task at all. I'm currently investigating it.

 

[Gimbel]

We installed a Webport several years ago. It was replaced in less than 6 months by a Red Lion Data Station Plus. The Red Lion is much easier to program. It creates log files which are stored on its internal compact flash card accessible via web browser. These log files can be automatically copied to an FTP server, or via a program running on a PC be copied to a hard drive.

Sounds like a nice module.

For the logfiles created by the module, will it be possible to decide the exact content of these I mean ex. time/date/unit.no/variables from a PLC etc. and is it possible to name the logfiles with custom filenames?

 

[JesperMP]

You are focussing on 10% of the project.
The biggest expense and work is to get the data physically from the proces into some kind of i/o system.
To get the data into logfiles or databases will probably be selfevident, as soon as you know the physical i/o system.

So, have you figured out where and how the data must be physically retrieved from the proces ?
Shall it be a completely autonomous system ?
Or can you tap the data from some of the existing controls ?

 

[OkiePC]

Sounds like a nice module.

For the logfiles created by the module, will it be possible to decide the exact content of these I mean ex. time/date/unit.no/variables from a PLC etc. and is it possible to name the logfiles with custom filenames?

Yes, you can create custom log files and write code in the Red Lion unit to make them contain whatever you want and name them however you like. Writing that code is not too difficult. The Crimson software is quite powerful and pretty easy to learn.

The drawback to doing this (at least with the G3 HMI, not sure about the data station) is that you may end up with more frequent writes to the memory card where this data is stored. I have a G306 logging data (about 10,000 to 12,000 items per day), and at first I used custom logging, but later switched to their built in logging features to take advantage of its built in ability to cache the writes and hopefully extend the life of the memory card. The built in data logging system saves the writes to memory and only executes writes to the memory card once every 2 minutes. After 4 months, I have had no issues. Last month, I set up the FTP connection, so now all that data is automatically sent to a server every hour.

 

[Gimbel]

Hi again,
Sorry I haven't responded earlier, but just wanted to thank all for the answers I got.

I have now finalized the system and actually the RedLion hint started me out in the direction I chose. I ended up using the G303 panel from RedLion along with a AB PLC and an AB Inview panel, having all components communicating via ethernet.

All systems have been integrated and the customer seems to be very happy.

Thanks again for your help

/Gimbel