Chapter 8 ____________________________________________________________ Technical Data
VAISALA ______________________________________________________________________ 167
Calculated Variables
Table 34
Calculated Variables (Typical Ranges)
Variable
HMT331 Probe
HMT333 Probe
HMT334/335/337/338
Probes
Dewpoint temperature
-20 ... +60 ºC
-20 ... +80 ºC
-20 ... +100 ºC
Mixing ratio
0 ... 160 g/kg dry air
0 ... 500 g/kg dry air
0 ... 500 g/kg dry air
Absolute humidity
0 ... 160 g/m
3
0 ... 500 g/m
3
0 ... 500 g/m
3
Wet bulb temperature
0 ... 60 ºC
0 ... +100 ºC
0 ... +100 ºC
Enthalpy
-40 ... +1500 kJ/kg
-40 ... +1500 kJ/kg
-40 ... +1500 kJ/kg
Water vapor pressure
0 ... 1000 hPa
0 ... 1000 hPa
0 ... 1000 hPa
Accuracies of Calculated Variables
Accuracies of the calculated variables depend on the calibration accuracy
of the humidity and temperature sensors; here the accuracies are given
for ± 2 %RH and ± 0.2 °C.
Accuracy of Dewpoint Temperature °C
Relative
humidity
Temp.
10
20 30 40 50 60 70 80 90 100
-40
1.86
1.03 0.76 0.63 0.55 0.50 0.46 0.43
—
—
-20
2.18
1.19 0.88 0.72 0.62 0.56 0.51 0.48
—
—
0
2.51
1.37 1.00 0.81 0.70 0.63 0.57 0.53 0.50 0.48
20
2.87
1.56 1.13 0.92 0.79 0.70 0.64 0.59 0.55 0.53
40
3.24
1.76 1.27 1.03 0.88 0.78 0.71 0.65 0.61 0.58
60
3.60
1.96 1.42 1.14 0.97 0.86 0.78 0.72 0.67 0.64
80
4.01
2.18 1.58 1.27 1.08 0.95 0.86 0.79 0.74 0.70
100 4.42
2.41 1.74 1.40 1.19 1.05 0.95 0.87 0.81 0.76
120 4.86
2.66 1.92 1.54 1.31 1.16 1.04 0.96 0.89 0.84
140 5.31
2.91 2.10 1.69 1.44 1.26 1.14 1.05 0.97 0.91
160 5.80
3.18 2.30 1.85 1.57 1.38 1.24 1.14 1.06 0.99
Accuracy of Mixing Ratio g/kg (Ambient Pressure
1013 mbar)
Relative
humidity
Temp.
10
20 30 40 50 60 70 80 90 100
-40
0.003
0.003 0.003 0.003 0.003 0.004 0.004 0.004
—
—
-20
0.017
0.018 0.019 0.021 0.022 0.023 0.025 0.026
—
—
0
0.08
0.09 0.09 0.10 0.10 0.11 0.11 0.12 0.13 0.13
20
0.31
0.33 0.35 0.37 0.39 0.41 0.43 0.45 0.47 0.49
40
0.97
1.03 1.10 1.17 1.24 1.31 1.38 1.46 1.54 1.62
60
2.68
2.91 3.16 3.43 3.72 4.04 4.38 4.75 5.15 5.58
80 6.73
7.73
8.92
10.34
12.05 14.14 16.71 19.92 24.01 29.29
100
16.26
21.34 28.89 40.75 60.86 98.85 183.66
438.56
—
—
120
40.83 74.66 172.36 —
—
—
—
—
—
—
