Patent ID: 6200443
Filing Date: 2001-03-13
Classification: G01N

Abstract:
A gas sensor comprising, in combination:a first electrode and a second electrode;an ion conducting, solid electrolyte membrane positioned between the first electrode and the second electrode, wherein ions migrate through the solid electrolyte membrane in response to the presence of a reactive gas at the first electrode; anda diagnostic device for diagnosing whether the sensor is operating properly, comprising:A) an applied voltage source coupled to the first electrode and the second electrode;B) a programmed processor, coupled to at least one of the electrodes and to the applied voltage source fori. applying a predetermined applied voltage across the electrodes during at least one charging portion of at least one test periodii. monitoring a monitored voltage across the electrodes in a discharge portion which occurs after the at least one charging portion of the test period and;iii. generating an output error signal if the monitored voltage corresponds to a faulty condition.