AWM43000 Series
Mass flow sensor for gases
OUTPUT FLOW VS
OUTPUT CURVES
INTERCHANGEABILITY
VS = 10 ±0.01 V, TA = 25°C
GAS CORRECTION FACTORS7
Gas type
Correction factor (approx.)
Helium (He)
Hydrogen (H2)
Argon (Ar)
0.58
0.78,9
0.95
1.0
Nitrogen (N2)
Oxygen (O2)
1.0
Air
1.0
Nitric oxide (NO)
Carbon monoxide (CO)
Methane (CH4)
Ammonia (NH3)
Nitrous oxide (N2O)
Nitrogen dioxide (NO2)
Carbon dioxide (CO2)
1.0
1.0
1.1
1.1
1.35
1.35
1.35
Notes:
7
Gas correction factors are referenced to nitrogen (N2) as calibration gas type. Approximate gas correction factors are provided
as guidelines only. Individual gas types may perform differently at temperature extremes and varying flow rates.
When sensing Hydrogen (H2) or Helium (He) it may be necessary to power the mass flow sensor using increased supply voltage:
Hydrogen typ. 12 V, Helium typ. 15 V
Hydrogen (H2) flow measurement requires the use of a special sensor. These devices provide normal operation when sensing
hydrogen flow and are designated with an "H" at the end of the order number.
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