Delta OHM HD2001 Manual De Instrucciones página 8

Calibration of the relative humidity sensor
ATTENTION: to calibrate the relative humidity sensor correctly it is fundamental to
know and abide by the physical phenomena on which the measurement is based:
this is the reason we recommend evaluating a new calibration carefully before
intervening and, in case it is to be performed, we recommend following all that is
reported below rigorously.
Calibration of the humidity sensor offset:
1. Enter the probe in the container with the saturated solution at 75% relative
humidity at about 20°C. Wait at least 30 minutes.
2. Using the MENU button select the item "ENaBLe CALibration", press the UP
arrow until reaching #51: the calibration procedure is started automatically.
3. The display indicates "CAL RH". Using the arrows, adjust the relative humidity
value indicated on the display according to the temperature of the calibration
salts: the value to be set is shown on the container's label of the saturated salt
used.
4. Wait a few minutes to ensure the reading is stable.
5. Press ENTER to confirm this value. The instrument returns to normal measure-
ment.
6. Remove the probe from the container and close it immediately using its lid.
Calibration of the humidity sensor slope:
1. Enter the probe in the container with the saturated solution at 33% of relative
humidity. Wait at least 30 minutes.
2. Using the MENU button select the item "ENaBLe CALibration", press the UP
arrow until reaching #51: the calibration procedure is started automatically.
3. The display indicates "CAL RH". Using the arrows, adjust the relative humidity
value indicated on the display according to the temperature of the calibration
salts: the value to be set is shown on the container's label of the saturated salt
used.
4. Wait a few minutes to ensure the reading is stable.
5. Press ENTER to confirm this value. The instrument returns to normal measure-
ment.
6. Remove the probe from the container and close it immediately using its lid.
HD2001.2: Temperature, humidity, pressure, air speed, serial output.
Note: the calibration of the sensor is usually carried out on both points, first
at 75%RH and then at 33%RH, but can be carried out on one of the points
only, to regulate a small departure at 75% or 33%, for example.
On exiting calibration the instrument checks if the procedure was carried out
correctly and signals any anomaly by making the CAL symbol blink.
If the blinking occurs at the end of the calibration of one of the two points, it
means the other point also needs calibrating.
Table 4 - Technical information (@ 24Vac and 25°C)
HD2001
Inputs
Temperature Sensor
Working range
Accuracy
Humidity Sensor capacity
%RH working
range
TD working range
Accuracy
600...1100mbar - 600...1100hPa - 60.0...
Pressure Working range
Accuracy
Fluid contacting
the membrane
Wind speed Type of sensor ----
Working range ----
°C working range ----
Accuracy ----
Outputs
Communications Type
Maximum Baud
Rate
Alarm Type of output
Maximum voltage
Maximum power
Temperature, %RH, dew
Variables point TD, barometric pres-
sure, pressure drop.
Analog Type of outputs ---
Load resistance ---
Resolution ---
Power
Software
Environmental
Temperature range
conditions
Humidity range
Protection degree
8 8
HD2001.1 HD2001.2
NTC 10kΩ
-20 ... +80°C
±0.3°C in the range 0...+70°C
±0.4°C outside this range
300pF
5...98%RH
-20 ... +80°C
±2.5%RH
110.0kPa
±0.5mbar @25°C
Air – Non corrosive gas - No liquids
---- Hot-wire
---- 0...5m/s
---- -20 ... +80°C
---- ±0.1m/s @25°C
RS232C and Multidrop RS485
9600 baud
Open collector (low-activated)
30Vdc
200mW
Temperature,
%RH, dew point
Temperature,
TD, barometric
pressure, pres-
sure drop and
wind speed
4...20mA
0...20mA
---
0...10Vdc
2 ... 10Vdc
Current output: Current output:
500Ω max
---
Voltage output: Voltage output:
100kΩ min
16bit ---
24Vac ±10% 50...60Hz (230Vac ±10% on request)
DeltaMet8
-20 ... +80°C
0...90%RH - (without condensation)
Electronic IP67
HD2001.3
----
----
----
----
----
----
----
%RH, dew
point TD
4...20mA
0...20mA
0...10Vdc
2 ... 10Vdc
500Ω max
100kΩ min
16bit