HMM30C MODULE
HMM30C
U312en-1.3
Operating Manual
99-11-29
The calibration interval depends on the surrounding conditions and the desired accuracy.
It is recommended to perform a calibration at least once a year. However, long term
exposure to certain chemicals and gases, e.g. some organic solvents, acids or bases may
cause drift in the sensor response. If there is a reason to believe that such conditions exist,
it is recommended to check the calibration at a shorter interval after taking the HMM30C
into use. Make the first check/adjustment after 6 months and 12 months and later extend
the interval to one year.
REPLACEMENT OF THE HUMICAP
SENSOR OR THE FILTER
If the sensor is damaged for some reason, remove it and insert a new one. Handle the
sensor by the plastic socket. DO NOT TOUCH THE SENSOR PLATE. Check the output
after sensor change. If it deviates too much from the reference value, recalibrate the
module.
Replace or clean a dirty filter. The sensor can be cleaned with distilled water; if this does
not help, replace the sensor. Do not use any mechanical methods.
TECHNICAL DATA
Relative humidity
Measurement range
0...100 %RH
Accuracy at +20 °C
(including calibration
inaccuracy, linearity and
repeatability):
±2 %RH (0...90 %RH)
±3 %RH (90...100 %RH)
Temperature coefficient
±0.04 %RH/°C (NOTE: after T compensation)
Humidity sensor
Vaisala HUMICAP
capacitive polymer sensor
Electronics
Output
Supply voltage
DC
DC
AC
0...1 V
10...35 V
9...24 V
0...5 V
14...35 V
12...24 V
0...10 V
19...35 V
16...24 V
0...20 mA
10...35 V
9...24 V (R
L
= 0 ohm)
0...20 mA
20...35 V
17...24 V(R
L
= 500 ohm)
Recommended external
load for outputs
> 10 kohm
Current consumption
15 mA max.
