Method and device for eliminating the noise voltage, superimposed onto a measured direct voltage, of an electrochemical measuring cell and for the rapid tracking of the variation of the measured value in the event of gas concentration changes

摘要

The invention relates to a method for eliminating the noise voltage, superimposed onto a measured direct voltage, of an electrochemical measuring cell and for the rapid tracking of the variation of the measured value in the event of gas concentration changes. The influence of said noise voltage, which falsifies the measuring result, is eliminated by a noise voltage limit setpoint (UR) being defined; if the limits (c, d) of the setpoint are not exceeded by the present measured value (Umi) of the measuring cell, a mean value (Uni) is formed; if the current measured value (Umi) does exceed the setpoint limits (c, d) because of a gas concentration change, the current measured value (U'mi) replaces the hitherto existing mean value (Uni) as the new mean value (U'ni), thus achieving a short measured-value setting time in the event of gas concentration changes.