METHOD FOR DIAGNOSING AN ELECTRICAL LEAD TO AN ELECTRODE OF A SENSOR ELEMENT FOR SENSING AT LEAST ONE PROPERTY OF A MEASURED GAS IN A MEASURED GAS SPACE

摘要

A method for diagnosing an electrical lead to an electrode of a sensor element, for sensing at least one property of a measured gas in a measured gas space, in particular for sensing a proportion of a gas component in the measured gas or a temperature of the measured gas, is described. A measured signal indicating an internal resistance of a pump cell of the sensor element is investigated for regularity upon switching on of the control unit. Upon identification of at least one irregularity of the measured signal, a suspected fault in the lead is identified and at least one substitute action is taken. The substitute action is selected from: an application of control to the heating element which is provided for a fault situation, a check of the validity of the measured signal, and a monitoring of the heating element. A sensor apparatus is also described.

主权项

1. A method for diagnosing an electrical lead to an electrode of a sensor element to sense at least one property of a measured gas in a measured gas space, the sensor element including a layered structure having at least one solid electrolyte layer, at least two electrodes, and a heating element, the electrodes being interconnected by the solid electrolyte layer to form an electrochemical pump cell, the heating element being embodied to heat the electrochemical pump cell, the electrodes being connected via an electrical connection to a control unit, the electrical connection encompassing the electrical lead, the method comprising:
checking for regularity a measured signal indicating an internal resistance of the pump cell upon switching on of the control unit; and identifying a suspected fault in the lead, and taking at least one substitute action upon identification of at least one irregularity of the measured signal, the substitute action being selected from: an application of control to the heating element which is provided for a fault situation, a check of the validity of the measured signal, and a monitoring of the heating element.