Operating method for a group of pressure sensors

A method (100) for operating a group (1) of pressure sensors, wherein the group comprises at least a first pressure sensor (1′) having a first pressure measurement range (4′) and a second pressure sensor (1″) having a second pressure measurement range (4″), wherein the first and second pressure sensors are arranged in such a manner that they can measure the pressure in a common measurement volume (2), wherein the first (4′) and second (4″) pressure measurement ranges overlap in an overlap pressure measurement range (6), and wherein the method comprises the steps of:

• aa) reading out (101) a first measurement signal of the first pressure sensor and a second measurement signal of the second pressure sensor substantially simultaneously while the pressure in the common measurement volume is in the overlap pressure measurement range;
• bb) stipulating (102) the first measurement signal which has been read out as an adjustment point for the second pressure sensor;
• cc) determining (103) a calibration parameter (K1), in particular a gas-dependent calibration parameter, for the second pressure sensor as a function of the first measurement signal, as a function of the adjustment point as stipulated in step bb) and as a function of the second measurement signal;
• dd) reading out (104) a further first measurement signal of the first pressure sensor and a further second measurement signal of the second pressure sensor substantially simultaneously while the pressure in the common measurement volume is in the overlap pressure measurement range, wherein the pressure in the common measurement volume is different from the pressure in step aa);
• ee) stipulating (105) the further first measurement signal which has been read out as a further adjustment point for the second pressure sensor;
• ff) determining (106) a further calibration parameter (K2), in particular a further gas-dependent calibration parameter, for the second pressure sensor as a function of the further first measurement signal, as a function of the further adjustment point stipulated in step ee) and as a function of the further second measurement signal,
• wherein a current pressure measurement value in the measurement volume is determined as a function of a current second measurement signal and the determined calibration parameters (K1, K2), and
• wherein the further calibration parameter determined in step ff) is a slope in a double-logarithmic function diagram of the second measurement signal as a function of the first measurement signal, or wherein a slope in a double-logarithmic function diagram of the second measurement signal as a function of the first measurement signal is calculated from the calibration parameter determined in step cc) and the calibration parameter determined in step ff), and wherein the method further comprises:
• hh) determining (108) a deviation of this slope from a slope expected for a reference gas;
• ii) comparing (109) the deviation determined in step hh) with a predetermined tolerance threshold for the deviation;
• and
• jj) triggering (110) an alarm for presence of water vapor in the common measurement volume (2) if the tolerance threshold is exceeded.