SICK EuroFID, Operating Instructions Manual

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“Maintenance” Sub-menu Functions
EuroFID · Operating Instructions · 8011094 V2.3 · © SICK AG 105
11.3.2
Calculation of conversion factors
Conversion of volumetric concentrations into mass concentrations
Formula:
Example:
Conversion of C mass concentration in the total mass concentration
Formula:
Example:
●
The mass concentrations refer to sample gas containing steam (“moist”)
under normal conditions.
●
The mass concentration values must be converted for other pressure or
temperature conditions in accordance with the gas laws.
M
M
[mgC/m 3 ] = M
E
[ppm] ·
12 N
E
V
M
[L/mol]
Parameter Significance
M
M
Measured value as mass concentration [mgC/m 3 ]
M
E
The measurement displayed by the EuroFID in [ppm]
N
E
Number of carbon atoms in the molecules of the span gas with which the
EuroFID was calibrated (e.g. for propane N
E
= 3)
V
M
Molar volume. Under normal conditions 1 : V
M
= 22.4 [L/mol]
1 Temperature = 0 °C, pressure = 1013 hPa
Measuring component: Propane (C
3
H
8
)
Employed span gas: Propane
Displayed measured value: 5 7 p p m
M
M
= 57 ·
12 · 3
= 57 · 1.607 = 91.6 mgC/m 3
22.4
M
R
= M
E
·
M
M
12 · N
R
· Rf
Parameter Significance
M
R
Mass concentration of the measuring components in the sample gas
M
E
Measurement displayed by the EuroFID in [mgC/m 3 ] (C mass concentration)
M
M
Molar volume = 22.4 L/mol (under normal conditions
1
)
1 Temperature = 0 °C, pressure = 1013 hPa
N
R
Number of carbon atoms in the molecules of the measuring components
Rf Response factor of the measuring components ( → P. 106, Table 10 )
Displayed measured value: 1 7 . 2 m g C
Measuring component: Toluol (C
7
H
8
)
Molar mass [g/mol]: 92.14
Response factor: 0.96
M
R
= 17.2 ·
92.14
= 19.6 mg/m
3
Toluol
12 · 7 · 0.96