06-28-2011 12:51 PM
Dunno if this is the proper place to post this, as it is my first time trying to contribute to the forums, so preemptive apologies to any admins having to move it!
Anyways- I came across these forums a while ago looking for a VI to run the PAR 263a potentiostat. I found one, but didn't really know how the heck it worked (and it seemed to contain a lot of redundancies), so I made my own anyways, and it seems to work for my applications, at least. So I thought I'd share it with all of you. I tried to include plenty of text boxes to help you understand what is going on and why- that way you can be spared the joy of having to figure out how it works on your own!
A few notes, though--
1.) The "future improvements" is more of a note to myself, not a plea for help. If I ever get around to/need to incorporate those adjustments, I'll be sure to share an updated VI. In the meantime, if you improve it, please share your work with the rest of us!
2.) There was an issue where even though the "WCD" (wait till curve is done) command was sent after initiating the scan, the program would continue, and, as a result, return an incomplete array for the current measurements. In order to get around this, I threw in a time delay that should give the potentiostat plenty of time to finish recording the curve before being asking it to be dumped. For slower scan rates this is necessary, but for faster scans (>100 mV/s) you can probably get rid of the delay and instead just run it with the lightbulb on.
3.) For whatever reason the potentiostat seems to hang up sometimes when running the program. If the TALK light stays on too long, stop the program and restart the 263a. This seems to be a hardware issue, as the other VIs I found online seem to suffer the same problem.
4.) IMPORTANT-- This assumes a GPIB Address of 13. The default for the device is 14, so either make sure to change it in the system settings on the front panel of the device, or change the 13 to a 14 in the VI.
Also, some credit goes out to roadchem for some ideas in the programming here. Thanks!
Any comments, complaints, suggestions, or pancakes are appreciated! Hope this helps some of you out!
Solved! Go to Solution.
06-28-2011 01:57 PM
I would suggest you dump the low level GPIB functions and use NI-VISA. You can then dump all of the GPIB Status functions. Make your resource selection (GPIB Address) a front panel control. You never want to have a user go to the block diagram. With a VISA Resource Control, you simply select the instrument from a pull-down menu that is automatically populated.
If you really are running with Highlight Execution Mode on, you really need to do some additional debug. That is not an acceptable way to run a VI. The problem needs to be fixed and not band-aided.
Get rid of the local variables. I would suggest using the Format Into String instead of those dedicated conversion functions and the Concantanate Into String.
06-28-2011 02:01 PM
Thanks! I realize it's a pretty shoddy patch job with the timing, but it's been doing the job. I had never tried using the NI-VISA, but I'll give it a try.
09-02-2011 10:35 AM
I am very interested in your application but unfortunatly I have the 8.5 version of Labview and I can't use it. Would you have a way to make it compatible with the 8.5?
Thank your for your help.
09-06-2011 02:49 PM
I have saved the mentioned VI for previous version (8.5) and attached it to this post. For future reference, there is also a dedicated downconvert thread that may be faster and more helpful. This thread seems a few months old and the original poster may not be checking any longer.
Downconvert VI Requests
07-04-2014 07:39 PM
I actually found a plece where you can buy cyclic voltammetry art 🙂
It's a like a store for metal art and they can take your data and make it into art that you hang on the wall 🙂