Ionic sensor calibration - incosistent been 8+ hours

libelium-dev
Posts: 27967
Joined: Mon Sep 28, 2009 1:06 pm

Re: Ionic sensor calibration - incosistent been 8+ hours

Post by libelium-dev » Mon Jun 04, 2018 8:48 am

Hi,

If the sensors aren't showing stable measurements, the problem could be on the reference probe. The measurements of the ions sensors depend on the reference probe.

According to the manufacturer of the sensors, the life expected for these sensors is around 6 months. The chemical reactions that take place in the sensors stop working although sensors had a low usage.

Yes, we have another customers with ions sensors developed successfully. Our experience tells us that sensors must be calibrated frequently and that their life expected is around 6 months if you want to obtain precise values.

Regards

JessieP
Posts: 90
Joined: Fri May 27, 2016 2:39 pm

Re: Ionic sensor calibration - incosistent been 8+ hours

Post by JessieP » Wed Jul 18, 2018 1:56 am

We went ahead and purchased a brand new reference probe and Cl- Ion selective probe - same results will not calibrate. We purchased brand new calibration medium and even used our pre-paid support hours to have Libelium review our code to confirm it was in order.

After two weeks of calibration, starting with calibration medium #3 letting it settle for over 24 hours, then repeating the process with calibration medium #2 for 24+ hours, then repeating the process with calibration medium #1 for 24+ hours. Then repeating the aforementioned process three times (so that is 72 hours of calibration in EACH concentration) we were still not able to obtain a consistent voltage. The same slow drift, it has consumed hours upon hours of our time.

If there is anyone that has these ion selective probes working please let me know: jpratt@post.harvard.edu

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest