RS 485 and labview (for use with Brooks 5850s mass flow controllers)

[stu22]

Hi, i'm currently going to be writing a piece of software to control RS 485, brooks 5850s mass flow controllers. First question is does anybody have any drivers for these mfc'. If not i would appreciate any examples(PROGRAMS ETC.), advise on RS 485, addressing RS 485 as i will be using 24 mfc's, any advise on the using the hart protocol to communicate with these mfc's. Also, even if its not relevant to what i'm doing any examples will do. Any advise greatly appreciated.

Thanks Stuart

[Khalid]

Hello Staurt,

I found the following on the Net:

http://www.engineeringtalk.com/news/flb/flb104.html

So you could use the "Brooks Smart DDE software" with LabVIEW. The DDE VIs in LabVIEW are not on the palette anymor. You can get to them by going to vi.lib\Platform\dde.llb. You may want to first take a look at the DDE example VIs at: examples >> comm >> ddeexamp.llb.

I am guessing the "Brooks Smart DDE software" will take care of talking to the controllers via the 485 port and all you would need to do is get the data from it using DDE.

Not sure why they're (still) using DDE.. it's not very reliable and a dying technology. You may want to ask the vendor if they have an OPC Server. That would be a better solution. Also, the article say
s the controllers now support the Profibus protocol. This is another option. You would have to use a Profibus interface card in your PC and it should support OPC. NI sells (used to sell?) one such Profibus card:

http://zone.ni.com/devzone/conceptd.nsf/webmain/5913E03F551DE3F786256A32005B4586?opendocument

You can then use either DataSocket or the Datalogging and Supervisory Control Module for LabVIEW as the OPC Client.

Finally, if you know the protocol for the controller, you can write your own driver-VIs. This would be some work on your part. A starting point would be the Serial examples at: examples >> instr >> smplserl.llb.

Hope this gives you a few options to consider.

Regards,

Khalid

[Ben]

I did an app that used these a couple of years ago.

Brooks had a LV example that used the DDE interface to the their dirver.

I used that as a guide and was able to figure out what I needed.

Brooks support fro their example was pretty limited. I remember getting a phone call back (a day latter) from their "LV expert" (uh- hem) who said that I had to have LV installed if I wanted the get the example to work!

The DDE interface required having the Brooks interface running if I remeber correctly. There was also some confusion over which version of their driver actually worked.

Since then I think I may have read something that made me think that Modbus OPC may handle these devices. I never followed up that idea so do not waste to much time on that.

B
en

[Ravid]

Hi Stuart,

Not that this is much help, but I had a look at doing the same thing. The other answers are correct - Brooks do offer a DDE based solution to communicate to their controllers. Unfortunately I wanted to use Labview RT (not Windows based), and therefore the DDE solution was not feasible.

I had a look at writing my own drivers using RS 485 and the Hart based protocol, but this seemed like too much work for our time frames.

I ended up ordering the controllers with DeviceNet communications option. The Brooks manual for this seems pretty good, and I am busy developing the application.

good luck with the drivers,
Regards,
Ravid

[stu22]

Hi, thanks for your help. i've just been told by my supplier of mfc's that there is no labview example for these mfc's. If u still have it could i have a look at it. be much appreciated.

Thanks Stuart

[Ben]

Hi Stuart,

I tried 3 times to post my files and it would not work!

They must be to big.

E-mail me at

bar@dsautomation.com

and I will reply with my collcetion of files from Brooks.

Now forgive the following;
In my 1000 or so answers I have posted to date, I have carefully avoided any answer that involved making money. Well, I am about to break that rule.

The app I mentioned earlier was designed such that the interface to Brooks could be easily broken out and re-used. If you are interested in purchasing my source code "AS IS", I could also forward a design document that explains how the original app worked.

Otherewise, I will reply with the Brooks files and pray for your success.

Trying to help,

Ben

[Ben]

One more thing;

I used these devices in another project.

In that case we used Brooks 154E's that were controlled and monitored using AI and AO from FP.

So there are other options.

The Brooks Smart DDE software let users manage the calibration and other settings of the MFC's. I would be very suprised if they discontinued support.

Trying hard to help,

Ben

[stu22]

Hi, thanks for your response, sorry i'm so late in replying(been on holiday). if u could send the brokes vi's to this address liversj@matthey.com it would be much appreciated.And i would be interested in purchasing the source code.

Thanks Stuart

[Ben]

I will send the files you requested as a reply to your e-mail.

Ben

[Benoit_PF]

Hello

Very interesting...
Could you send me the basics for this MFC ?
I'll send you an e-mail.

Thanks