Digital, high resolution oxygen sensor
The technology of electrochemical cells (ECs) for gas sensing is well established and the ECs form the basis of an entire industry for safe monitoring of oxygen as well as safe monitoring of poisonous gases. However, safe monitoring of oxygen using ECs normally means coping with loss of signal sensitivity by frequent check-ups and replacement of the cells every 12-18 months. The reason why regular ECs so quickly loose sensitivity and has to be replaced quite often, is because the electrolyte is very strong and the activity wear out quickly. Recent developments of weak acid based ECs has overcome the problem of fast wear out and these cells are excellent choices for safety and process monitoring in various additive manufacturing applications.
The PO2ES-103D is an example of a rugged electrochemical cell with a weak acid electrolyte that can easily be adapted (screw-mounted) into the application. The lifetime of the cell exceeds 1.200.000 %Vol O2 hours and the End-Of-Life (EOL) is easy to detect. The sensor is lead free and is conform to recent RoHS/Reach directives. Most industrial requirements for oxygen sensors call for a low-drift baseline, signal stability and ease of calibration. The basic PO2ES-103D sensor has a build-in 16 bit AD converter that delivers a highly stable, temperature independent signal with a resolution < 100 ppm. The drift is less 1% per month, averaged over 12 month. The PO2ES-103D sensor has zero baseline lower than 1500 ppm O2 and very stable, making it very suitable for controlled atmosphere applications in a range from a few hundred ppm O2 and higher.