Michell Instruments QMA401, Руководство пользователя

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QMA401 User’s Manual
64 97450 Issue 2, March 2018
APPENDIX B
Appendix B Calculating Conversion Factors for Gas Mixes
Setting the correct flow rate is crucial to correct operation of the QMA401. If the gas being sampled
contains multiple components, then the conversion factor must be calculated and entered as a ‘user’
carrier gas.
The conversion factor will be altered for gas mixtures as follows:
1
1
+
=
= C
mix
C
mix
V
1
C
2
+
V
2
C
n
V
n
V
n
C
n
C
Conversion factor for the gas mix
=
Conversion factor for the gas ‘n’
=
Conversion factor for the gas ‘n’ in the mix
For example, if the gas mixture contains:
10% N
2
C
1
= 1.000
30% Ar
C
2
= 1.395
50% CH
4
C
3
= 0.7419
10% CO
2
C
4
= 0.7186
1
1 1.395
0.8865
0.1 0.3
+
0.7419
0.5
+
0.7186
0.1
+ =
=
C
mix C
mix
Below are the conversion factors for some common gases. If the gas you are measuring contains a
component that is not on this list, please contact your Michell representative.
1.000 Air
1.395 Ar - Argon
0.742 CH
4
- Methane
0.594 C
2
H
2
- Ethyne
0.568 C
2
H
4
- Ethelyne
0.466 C
2
H
6
- Ethane
0.377 C
3
H
6
- Propylene
0.320 C
3
H
8
- Propane
0.238 C
4
H10 - Butane
0.999 CO - Carbon Monoxide
0.718 CO
2
- Carbon Dioxide
1.019 H
2
- Hydrogen
1.422 He - Helium
1.446 Kr - Krypton
1.002 N
2
- Nitrogen
1.415 Ne - Neon
0.757 NH
3
- Ammonia
0.971 NO - Nitrogen Oxide
0.694 N
2
O - Nitrous Oxide
0.978 O
2
- Oxygen
1.339 XE - Xenon