HD32.1
- 69 -
V2.1
6.2.3 Measurement of relative humidity using the combined humidity/temperature probe
The instrument works by using combined humidity/temperature probes (temperature with Pt100
sensor). The combined humidity/temperature probes are fitted with SICRAM module that acts as an
interface between the sensor on the probe and the instrument. There is a microprocessor circuit with
a permanent memory inside the module that enables the instrument to recognize the type of probe
connected and to read its calibration information.
The probes are detected during turn on, and this cannot be performed when the instrument is
already on, therefore if a probe is connected and the instrument is on, it is necessary to turn it
off and on
.
Measurement of relative humidity
The humidity probes are humidity/temperature combined probes: The humidity sensor is a
capacitive type sensor, the temperature sensor is a Pt100 (100
Ω
at 0°C).
The instrument measures relative humidity %RH and temperature, and starting from the fixed
barometric pressure value of 1013.25mbar it calculates the following resulting quantities:
•
g/kg Grams of vapor in a kilogram of dry air
•
g/m
3
Grams of vapor in a cubic meter of dry air
•
hPa Partial vapor pressure (hPa)
•
J/g Enthalpy
•
Td Dew point (°C or °F)
•
Tw Wet bulb temperature (°C or °F)
A measurement is performed by placing the probe in the area of whose parameters you wish to
measure. Keep the probe far from elements that might interfere with measurement such as: heat or
sources of cooling, walls, air-streams, etc. Avoid temperature drops that might cause condensation.
A reading taken when no heat drop occurs is practically immediate. In contrast, in conditions
involving heat drops, it is necessary to wait until the sensors and their housing have reached a
thermal equilibrium in order to prevent heat irradiation or absorption on the relative humidity
sensor, which would cause a faulty measurement. Since temperature affects relative humidity; move
the probe like a fan in order to speed the response time in the presence of heat drops.
The calibration of the humidity/temperature sensor by the user is not required.
The humidity sensor is calibrated in our laboratory at 23°C at the points of 75%RH, 33%RH
and 11.4%RH. On request, the probes can be checked at different isotherms.
The temperature sensor is calibrated in the factory and the Callendar Van Dusen parameters
are recorded in the SICRAM module.
Summary of Contents for HD32.1
Page 6: ...HD32 1 6 V2 1 Thermal Microclimate HD32 1...
Page 78: ...HD32 1 78 V2 1 MIN 350 MAX 1020 120 AP471 S4...
Page 106: ...HD32 1 106 V2 1 Moderate Environment Norm ISO 7730...
Page 107: ...HD32 1 107 V2 1 Moderate Environment Norm ISO 7730...
Page 108: ...HD32 1 108 V2 1 Moderate Environment Norm ISO 7730...
Page 109: ...HD32 1 109 V2 1 Moderate Environment Norm ISO 7730...
Page 110: ...HD32 1 110 V2 1 Moderate Environment Norm ISO 7730...
Page 111: ...HD32 1 111 V2 1 Moderate Environment Norm ISO 7730...
Page 112: ...HD32 1 112 V2 1 12 2 WARM ENVIRONMENT Norm ISO 7243 Norm ISO 7243...
Page 113: ...HD32 1 113 V2 1 Warm Environment Norm ISO 7243...
Page 114: ...HD32 1 114 V2 1 Warm Environment Norm ISO 7243 Norm ISO 7243...
Page 115: ...HD32 1 115 V2 1 Warm Environment Norm ISO 7243...
Page 116: ...HD32 1 116 V2 1 Warm Environment Norm ISO 7243...
Page 117: ...HD32 1 117 V2 1 Warm Environment Norm ISO 7243...
Page 118: ...HD32 1 118 V2 1 12 3 DISCOMFORT ANALYSIS Norm ISO 7730 Norm ISO 7730...
Page 119: ...HD32 1 119 V2 1 Discomfort Analysis Norm ISO 7730...
Page 120: ...HD32 1 120 V2 1 Discomfort Analysis Norm ISO 7730...
Page 121: ...HD32 1 121 V2 1 Discomfort Analysis Norm ISO 7730...
Page 122: ...HD32 1 122 V2 1 Discomfort Analysis Norm ISO 7730...
Page 123: ...HD32 1 123 V2 1 Discomfort Analysis Norm ISO 7730...
Page 124: ...HD32 1 124 V2 1 Discomfort Analysis Norm ISO 7730...
Page 125: ...HD32 1 125 V2 1 12 4 HOT ENVIRONMENT Norm ISO 7933 Norm ISO 7933...
Page 126: ...HD32 1 126 V2 1 Hot Environment Norm ISO 7933...
Page 127: ...HD32 1 127 V2 1 Hot Environment Norm ISO 7933...
Page 128: ...HD32 1 128 V2 1 Hot Environment Norm ISO 7933...
Page 129: ...HD32 1 129 V2 1 Hot Environment Norm ISO 7933...
Page 130: ...HD32 1 130 V2 1 Hot Environment Norm ISO 7933...
Page 131: ...HD32 1 131 V2 1 Hot Environment Norm ISO 7933...
Page 132: ...HD32 1 132 V2 1 12 5 COLD ENVIRONMENT Norm ISO 11079 Norm ISO 11079...
Page 133: ...HD32 1 133 V2 1 Cold Environment Norm ISO 11079...
Page 134: ...HD32 1 134 V2 1 Cold Environment Norm ISO 11079...
Page 135: ...HD32 1 135 V2 1 Cold Environment Norm ISO 11079...
Page 136: ...HD32 1 136 V2 1 Cold Environment Norm ISO 11079...
Page 137: ...HD32 1 137 V2 1 Cold Environment Norm ISO 11079...
Page 138: ...HD32 1 138 V2 1 Cold Environment Norm ISO 11079...
Page 139: ...HD32 1 139 V2 1 Cold Environment Norm ISO 11079...
Page 140: ...HD32 1 140 V2 1 12 6 PHYSICAL QUANTITIES...
Page 153: ...HD32 1 153 V2 1 NOTES...
Page 154: ...HD32 1 154 V2 1 NOTES...
Page 155: ......