METHOD FOR MEASURING CONCENTRATION OF STEAM BY LIMIT CURRENT TYPE GAS SENSOR AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To continuously and accurately measure the concn. of steam by using a limit current type gas sensor. SOLUTION: A sensor calculates the ratio SL1 /SL1 ' of the oxygen concn. output signal SL1 shown corresponding to definite oxygen concn. Po by the sensor and the oxygen concn. output signal SL1 ' shown corresponding to the same oxygen concn. Po thereafter by the sensor to set the same an oxygen concn. correction factor (k) and multiplies the steam concn. output signal SL2 ' shown corresponding to steam concn. PH by the oxygen concn. correction factor (k) to calculate a correction signal k*SL2 '. The concn. of steam is operated from the correction signal k*SL2 ' on reference to the corresponding relation PH=f(SL2 ) [f; function mark] with the steam concn. PH and the steam concn. output signal SL2 of the sensor before deterioration.