Method for operating a sensor for detecting at least one property of a measurement gas in a measurement gas chamber

A method for operating a sensor for detecting at least one property of a measurement gas in a measurement gas chamber, wherein the sensor has a sensor element for detecting the property of the measurement gas, wherein the sensor element has at least one Nernst cell, at least one pump cell, and at least one heating element, wherein the method comprises the following steps:

• a) heating the sensor element for a predetermined heating period using the heating element;
• b) detecting an electrical resistance of the Nernst cell during the predetermined heating period and generating a signal indicating the resistance of the Nernst cell;
• c) detecting an electrical resistance of the pump cell during the predetermined heating period and generating a signal indicating the resistance of the pump cell;
• d) evaluating a temporal profile of the signals indicating the resistance of the pump cell and Nernst cell, wherein a check is made as to whether the signal indicating the resistance of the pump cell and/or the Nernst cell falls below a resistance threshold value within the predetermined heating period;
• wherein:
• e) when the evaluation reveals that the signal indicating the resistance of the Nernst cell does not fall below the resistance threshold value within the predetermined heating period, but the signal indicating the resistance of the pump cell has already fallen below the resistance threshold value, a temperature of the sensor element is controlled based on the signal indicating the resistance of the pump cell, and
• f) when the signal indicating the resistance of the Nernst cell still falls below the resistance threshold value before a diagnosis of line interruptions is enabled, regular heating operation is carried out using temperature control based on the resistance of the Nernst cell.

A system, comprising:

• at least one sensor configured to detect at least one property of a measurement gas in a measurement gas chamber, wherein the sensor has a sensor element for detecting the property of the measurement gas, wherein the sensor element has at least one Nernst cell, at least one pump cell, and at least one heating element;
• and
• at least one controller including at least one processor, wherein the controller is configured to;
• a) heat the sensor element for a predetermined heating period using the heating element,
• b) detect an electrical resistance of the Nernst cell during the predetermined heating period and generating a signal indicating the resistance of the Nernst cell,
• c) detect an electrical resistance of the pump cell during the predetermined heating period and generating a signal indicating the resistance of the pump cell,
• d) evaluate a temporal profile of the signals indicating the resistance of the pump cell and the Nernst cell, wherein a check is made as to whether the signal indicating the resistance of the pump cell and/or the Nernst cell falls below a resistance threshold value within the predetermined heating period, wherein:
• e) when the evaluation reveals that the signal indicating the resistance of the Nernst cell does not fall below the resistance threshold value within the predetermined heating period, but the signal indicating the resistance of the pump cell has already fallen below the resistance threshold value, a temperature of the sensor element is controlled based on the signal indicating the resistance of the pump cell, and
• f) when the signal indicating the resistance of the Nernst cell still falls below the resistance threshold value before a diagnosis of line interruptions is enabled, regular heating operation is carried out using temperature control based on the resistance of the Nernst cell.

A non-transitory data carrier on which a data structure is stored which is configured to carry out a method after being loaded into a working and/or main memory of a computer or computer network, the method being for operating a sensor for detecting at least one property of a measurement gas in a measurement gas chamber, wherein the sensor has a sensor element for detecting the property of the measurement gas, wherein the sensor element has at least one Nernst cell, at least one pump cell, and at least one heating element, and the method comprising the following steps:

• a) heating the sensor element for a predetermined heating period using the heating element;
• b) detecting an electrical resistance of the Nernst cell during the predetermined heating period and generating a signal indicating the resistance of the Nernst cell;
• c) detecting an electrical resistance of the pump cell during the predetermined heating period and generating a signal indicating the resistance of the pump cell;
• d) evaluating a temporal profile of the signals indicating the resistance of the pump cell and Nernst cell, wherein a check is made as to whether the signal indicating the resistance of the pump cell and/or the Nernst cell falls below a resistance threshold value within the predetermined heating period;
• wherein:
• e) when the evaluation reveals that the signal indicating the resistance of the Nernst cell does not fall below the resistance threshold value within the predetermined heating period, but the signal indicating the resistance of the pump cell has already fallen below the resistance threshold value, a temperature of the sensor element is controlled based on the signal indicating the resistance of the pump cell, and
• f) when the signal indicating the resistance of the Nernst cell still falls below the resistance threshold value before a diagnosis of line interruptions is enabled, regular heating operation is carried out using temperature control based on the resistance of the Nernst cell.