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EuroFID · Operating Instructions · 8011094 V2.3 · © SICK AG
Product Description
2.1
Measuring principle
Fig. 1
Measuring principle
The EuroFID uses a flame ionization detector (FID) for measuring the hydrocarbons. A
hydrogen flame supplied by fuel gas and combustion air burns in the FID. The sample gas
is routed into this flame. The hydrocarbons contained in the sample gas are split; the
produced hydrocarbon fragments are ionized. A stream of ions forms in the electric field
and this electrical stream is measured.
The measuring signal is proportional to the number of the listed, non-oxidized hydrocarbon
atoms. Hydrocarbon atoms which are already oxidized are only partially detected.CO and
CO
2
are ineffective.
The quantitative correlations between the measurement signal and the hydrocarbon
concentration in the sample gas is determined by performing reference measurements
with calibration gases which do not contain any hydrocarbons (zero gas) or of which the
hydrocarbon concentration is known exactly (calibration gas – e.g. 80 ppm propane in air).
2.2
Measuring method
Instrument air
The EuroFID requires hydrocarbon-free instrument air for operation. The instrument air is
used in the EuroFID for the following purposes:
– As induction air for the ejector pump
– As combustion air for the FID
– As control air for regulation of the sample gas flow to the FID
– As zero gas for calibration
Heated sensor block
To prevent condensation in the sample gas path, the parts in contact with the sample gas
(sample gas filter, ejector, sample gas capillaries, bypass orifice plate, sensor) are
accommodated in a heated, thermostatically controlled “sensor block”. The constant
temperature is the pre-requisite for a constant sample gas flow to the FID. The temperature
in the sensor block depends on the individual measurement application (90 … 200 °C).
U=
Sample gas
Fuel gas
Combustion air (instrument air)
Summary of Contents for EuroFID
Page 10: ...Contents 10 EuroFID Operating Instructions 8011094 V2 3 SICK AG ...
Page 18: ...18 EuroFID Operating Instructions 8011094 V2 3 SICK AG Important Information ...
Page 80: ...80 EuroFID Operating Instructions 8011094 V2 3 SICK AG Start up ...
Page 88: ...88 EuroFID Operating Instructions 8011094 V2 3 SICK AG Operation General ...
Page 100: ...100 EuroFID Operating Instructions 8011094 V2 3 SICK AG Main Menu Functions ...
Page 144: ...144 EuroFID Operating Instructions 8011094 V2 3 SICK AG Maintenance Sub menu Functions ...
Page 154: ...154 EuroFID Operating Instructions 8011094 V2 3 SICK AG Calibration ...
Page 158: ...158 EuroFID Operating Instructions 8011094 V2 3 SICK AG Shutdown ...
Page 182: ...182 EuroFID Operating Instructions 8011094 V2 3 SICK AG Clearing Malfunctions ...
