Labview Drivers for Neslab chillers, Agilent 34970A, and Digikrom Monochromator

[bill_gilbert]

I know it's been a long time since anybody inquired about this, but a few months ago I rewrote the Neslab drivers that were available from the Instrument Driver Network for 10+ years, and in my experience really never worked right. I tested them with 3 different models that I have access to, and they now work fine. There were mistakes in the checksum calculation and some numeric parsing for the I and D parameters of the PID settings. Also the comm port selections didn't make sense, these are now VISA. They work for RS232, and RS485 for point to point comms with single chillers. A multidrop would require some work on traffic control.

I submitted then to IDN in LLB format for both LV 2008 and LV 2016. After a long delay they reposted them, having made them project style and combined them with some of the old stuff, in LV 2018, which I don't happen to have running.

Not sure whether the ones posted on IDN still work, since I'm pretty sure they can't test them on a chiller, and frankly I wouldn't bother, since I already spent enough time on this. The idea that they would modify code they are in no position to test is pretty discouraging.

For what it's worth, I posted them on Google drive with  drivers for the Agilent 34970A, which I've debugged over the years, and some for the Digikrom Monochromator:

https://drive.google.com/drive/folders/1BL4Kd6aWSk4RJE_-ip3OtyVlXdANtFzM?usp=sharing

Bill Gilbert

[SybQ]

I want to thank you for posting this. I was having difficulties running the driver uploaded in 2003-04 with LV 2020, and started my attempt to build my own VI from scratch. I received the checksum error message that you mentioned in your original post.

I can confirm that the VI works with the in Neslab RTE-740 using RS-232. My next steps are use your VI and create a ramp over time system around it.

Thanks again, you saved me a lot of time!

[bill_gilbert]

SybQ,

Thanks so much for the props! I wondered if anybody would ever find them useful. Of course I didn't create it from scratch, started with the old driver and worked from there, so whoever wrote the original did some heavy lifting. Glad to pay it forward, others have given me advice and code snippets over the years that saved my butt.

BG

[bill_gilbert]

As a footnote, when I was testing the driver, I connected to one of our chillers that we thought needed rebuilding. I was testing the PID reads, and it turned out someone had corrupted the PID settings (maybe by trying to write to them with old driver?). I restored the factory defaults, and bada bing, it started working just fine.

Apparently NESLAB knew something about tuning their chillers 😉

BG

[SybQ]

Thank you for the heads up. I did read the part in your demo cautioning users about bricking their controller by changing the PID settings. Really helpful!