Technical Paper
A Reliable Potentiometric NOx Sensor
2000-03-06
2000-01-1202
The NOx/O2 sensor has been developed based on a simple tubular design. It is a potentiometric sensor that gives out two sensor voltages: one for the O2 concentration, the other for the NOx concentration. The NOx sensor has been extensively tested in synthetic gases and in real exhaust gases. It gives a good response towards NOx and NO2 for O2 concentrations between 0.5 and 20.8%. The sensor can be used to detect NOx in the range from 10-1500 ppm. Typical gas lab measurements to check the sensitivity and cross-sensitivity are shown. Succesfull sensor testings before and after a lean NOx trap (LNT) on a GDI engine are performed. The sensors are also tested on an exhaust gas simulator to check their sensitivity towards NO in more realistic circumstances.
