It is well know that the majority of analyser problems and be directly attributed to the sample conditioning systems. To obtain a valid measurement it is imperative that both a representative sample is obtained and contaminates are removed. During the letdown liquids must also be prevented from forming.
Particulates pose an obvious problem - erosion of sensors leading to
inevitable drift and premature failure - hence filtration is generally required.
Liquid entrainment has less obvious effects; most substances are either hydrophilic or
hydrophobic (water attracting or repelling). Should these coat the sensor the balance with
the measured gas will alter - leading to an apparent offset. To counter this problem
coalescing filters are used to remove the liquids, and additional heat will ensure the
remainder will not condense out.
With analysers sometimes being located some distance from the tapping point slow reaction times, or the effects of Transpiration can cause problems. To reduce the lag or dilute its effects fast by-pass loops are installed.
Typical Applications: