Patent ID: 6404205
Filing Date: 2002-06-11
Classification: G01N

Abstract:
A method for testing an electrochemical gas sensor, wherein the electrochemical gas sensor includes a working electrode which electrochemically oxidizes or reduces a first gas component to be detected, a counter electrode which causes an electrochemical reduction reaction or oxidation reaction corresponding to an oxidized or reduced amount of the first gas component, and an electrolyte, and wherein a sensor output, which is a value of an oxidation current or reduction current of the first gas component, is calculated and a concentration of the first gas component is detected, comprising the steps of:applying a voltage in which the current flows in the reverse direction to the oxidation current or reduction current of the first gas component, between the working electrode and the counter electrode from an outside of the electrochemical gas sensor, so that the working electrode operates as a negative electrode and the counter electrode operates as a positive electrode; and after a second gas component is generated on the working electrode so as to be a predetermined concentration by the electrolysis of the electrolyte, measuring the sensor output which is a value of the oxidation current or reduction current on the working electrode of the second gas component, wherein a normal operation of the electrochemical gas sensor is determined if the second gas component has a sensor output substantially proportional to the sensor output of the first gas component in a concentration corresponding to the concentration of the first gas component.