Vaisala HMP240 - Manual (Page 64)

HMP240
User's Guide
M210300en
62
8. TECHNICAL DATA
Sensor RH & T composite sensor
HUMICAP
® KC(part no.
18258HM)
T sensor in the humidity sensor head Pt 100 IEC 751 class 1/3 B
Voltage proof, AC: DC supply (+ or -) to housing 250 VAC, 1 minute
(300 k
Ω
and 15 nF parallel)
8.1 Dewpoint temperature
typical range of dewpoint temperature -40...+100 °C
Response time (90 %) at +20 °C in 15 s
still air (with sintered filter)
0
1
2
3
4
5
6
0 20 40 60 80 100
Dewpoint difference (°C)
Difference between ambient temperature and dewpoint temperature
Accuracy in dewpoint
measurement (°C)
-20
0
20 40
60 -40
Dewpoint temperature (°C)
100
80
Figure 8.1 Accuracy in dewpoint measurement as a function of
depression and dewpoint (NOTE: dewpoint < 0
°C = calculation of
frostpoint)