Monitoring station for measurement of individual gas concentrations in gas or gas-liquid mixtures protects a sensitive sensor against high concentration damage by inert or diluent gas purging

摘要

Monitoring station for measurement of gas concentration, particularly oxygen, has detector e.g. fuel cell with lambda probe for covering high concentration, and down-stream connected, low concentration detector e.g. electro-chemical sensor, for ppm concentration range. If a concentration high enough to cause damage occurs, an inert/low oxygen purge gas flow is initiated through low concentration device by controller. Monitoring station for measurement of gas concentration, particularly oxygen, has a detector (2) e.g. a fuel cell with a lambda probe for covering the high concentration e.g. volume.% range, and a down-stream connected, low concentration detector (3) e.g. an electro-chemical sensor, for the ppm concentration range. In the event of a concentration high enough to cause damage, an inert, or low oxygen, purge gas flow (9) is initiated through the low concentration device by a controller (4).