Gas measuring device and gas measuring device for measuring of a target gas concentration and an ambient humidity

A gas measuring device for measuring the concentration of a combustible target gas, the gas measuring device comprising:

• a detector comprising a detector heating segment, the detector being configured to oxidize combustible target gas located inside the gas measuring device by heating the detector heating segment;
• a compensator comprising a compensator heating segment, the compensator being configured to oxidize combustible target gas located inside the gas measuring device to a lesser extent than the detector or the compensator being configured to not oxidize combustible target gas and/or the gas measuring device is configured such that a smaller quantity per time unit of combustible target gas from an environment of the gas measuring device reaches the compensator than the detector;
• a sensor arrangement configured to measure a first detection variable and a second detection variable;
• a temperature sensor configured to measure an indicator of ambient temperature in the environment of the gas measurement device;
• a signal-processing evaluation unit;
• and
• a data memory, the evaluation unit having at least temporary read access to the data memory, wherein a computer evaluable model is stored in the data memory, the stored model comprises a first functional relationship and a second functional relationship, the first functional relationship describes a dependence between a target gas concentration on the one hand and at least the first detection variable on the other hand, and the second functional relationship describes a dependence between a first further environmental condition on the one hand and the ambient temperature and at least one of the first detection variable and the second detection variable on the other hand, wherein the first further environmental condition is different from the ambient temperature and wherein the second functional relationship is valid at least if the concentration of the combustible target gas is below a predetermined concentration threshold,
• wherein the gas measuring device is configured to apply an electrical voltage to the detector such that an electrical current flows through the detector heating segment and the detector heating segment is heated, and to apply an electrical voltage to the compensator so that an electrical current flows through the compensator heating segment and the compensator heating segment is heated,
• wherein in a first alternative, the first detection variable depends on a detector temperature, which is a temperature of the detector heating segment, and the second detection variable depends on a compensator temperature, which is a temperature of the compensator heating segment,
• wherein in a second alternative, the first detection variable depends on both the detector temperature and the compensator temperature, and the second detection variable depends either on the detector temperature but not on the compensator temperature or depends on the compensator temperature but not on the detector temperature,
• wherein the evaluation unit is configured to determine the target gas concentration depending at least on the measured first detection variable and using the first functional relationship,
• wherein the evaluation unit is further configured to determine whether the second functional relationship is valid or not at the determined target gas concentration, and
• wherein the evaluation unit is further configured to determine, if the second functional relationship is valid, the first further environmental condition depending on the measured ambient temperature and at least one of the measured first detection variable or the measured second detection variable and using the second functional relationship.