LANDTEC GEM5000 Operating Manual page 84

GEM5000 gas analyzer
using certified methane mixtures and will give correct readings, provided there are no
other hydrocarbon gases present within the sample (e.g. ethane, propane, butane,
etc...). If there are other hydrocarbons present, the methane reading will typically be
higher than the actual methane concentration being monitored.
The extent to which the methane reading is affected depends upon the concentration of
the methane in the sample and the concentration of the other hydrocarbons. The effect
is totally non-linear and difficult to predict.
:
Note The effect can be reduced by using an H
order hydrocarbons. When using the H
the gas sample and clean air purge run-times, as using an H
increases the response time of the analyzer.
Carbon dioxide is measured by infrared absorption at a wavelength specific to carbon
dioxide. Therefore, the carbon dioxide reading will not be affected by any other gases
usually found on landfill sites.
The oxygen sensor is a galvanic cell type and suffers virtually no influence from CO
CO, H S, NO , SO
2 2
The infrared sensors will not be 'poisoned' by other hydrocarbons and will revert to
normal operation as soon as the gas sample has been 'purged'.
LANDTEC
or H , unlike many other types of oxygen cell.
2 2
5K-MNL-GEM5000
S filter as it can reduce higher
2
S filter you will need to increase
2
S filter
2
,
2
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