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OTT TRH

Weather sensor for humidity and temperature

The compact, long-term stability weather sensor OTT TRH is responsible for the measurement of relative humidity and temperature. In addition it can calculate the values for absolute humidity, dew point and mixing ratio and output these via the SDI-12 interface. A protective cap prevents dust and dirt from entering the sensor system. The included protective housing provides weather and radiation protection.
  • Air temperature and relative air humidity (measured), absolute air humidity, dewpoint and mixing ratio (calculated)
  • PT1000, capacitive
  • Low power draw, long-term stable, suitable for extreme temperatures, protective housing included
  • SDI-12 V1.3
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OTT TR2O Sensor

  • Calculation of absolute humidity, dew point and mixing ratio in addition to output of measured values
  • Long-term stable, can be used in extreme temperatures (– 40 °C to +80 °C)
  • Long service life thanks to rugged and compact design; a protective cap including metal grid filter provides protection against dirt, dust and insects
  • Very low power consumption
  • Easy conntection to SDI-12 data logger, e.g.OTT netDL via digital interface SDI-12 (protocol V1.3)

OTT RS7 Weather and Radiation Protection

  • Naturally vented protective housing fitted with 7 lamellae
  • UV- and weather resistant plastic
  • White outside coating and black inside coating for optimum protection against radiant heat
  • Practical stainless steel bracket for easy installation to horizontal or vertical pipes
  • Sensor is easily installed – simply insert it and tighten screw

OTT TRH is used in automatic weather stations, often together with  the OTT Pluvio2 series precipitation gauges:

  • in meteorology and hydrology
  • in environmental monitoring
  • in research projects
  • in agriculture and forestry
Leaflet - Digital humidity and temperature sensor with protective housing OTT TRH
OTT TRH - Diagramme Messgenauigkeit | Measurement Accuracy Diagrams
OTT TRH - Konformitätserklärung | Declaration of Conformity | Declaration de Conformité
OTT TRH - Kurzanleitung | Quick Reference | Notice d'utilisation simplifiée | Instrucciones abreviadas
OTT TRH - Technical Documentation SDI-12 Commands Temperature/Humidity Sensor
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Sensor TR2O
Sensor output
measured Temperature in °C or °F, relative humidity in %
calculated Absolute humidity in g/m³, dew point in °C or °F, mixing ratio in g/kg
Relative humidity
Measuring range 0 ... 100 % RH
Accuracy at 25 °C and 4.5 V DC ...15 V DC* (incl. repeatability, hysteresis and calibration uncertainty) max. ±2 % RH ( 0 … 90 % RH)**; max. ±3 % RH ( 90 … 100 % RH)**

*for supply voltages of>15V DC, other accuracy values apply
**temperature dependency: <±2% at -10°C ... 60°C
Resolution 0.10%
Repeatability ±0.1 %RH
Hysteresis <1 % RH
Long-term stability typ. < ±1.5 %/year
Response time wtih protection cap RH90 typ. <15 s at 0.35 m/s
Temperature
Sensor PT1000 DIN A
Measuring range -40 °C ... +80 °C
Accuracy at 4.5 V DC ...15 V DC* ±0.1 °C at 20 °C; ±0.5 °C at -40 °C, 80 °C linearity
Resolution 0.01 °C
Response time wtih protection cap T90 <300 s at 1 m/s airflow; T90 <250 s at 2 m/s airflow
Absolute humidity
Measuring range 0 ... 1000 g/m³
Resolution 0.1 g/m³
Dew point
Measuring range -40 °C ... +80 °C
Resolution 0.01 °C
Mixing ratio
Measuring range 0 ... 1000 g/kg
Resolution 0.1 g/kg
Interface SDI-12 V1.3
Supply voltage 4.5 V DC ... 28 V DC
Current consumption
Quiescent < 20 µA at 12 V
Temperature measurement typ. 550 µA
Humidity measurement typ. 260 µA
Ambient conditions
Operating temperature -40 °C ... +80 °C
Storage temperature -50 °C ... +80 °C
Operating humidity 0 ... 100 % RH
Protection class IP65
Sensor protection Protection cap with metal grid filter
Material and dimensions
Housing sensor Polycarbonate
Dimension sensor Ø 12 mm x 140 mm
Material cable PUR (black), moulded/shielded
Available cable lengths 3.5 m and 10 m
Wiring color code printed on housing
Standards EG (2004/108/EG), EN 61326-1:2006
OTT RS7 Weather and Radiation Protection
Number of lamellae 7
Operating temperature -40 °C ... +80 °C
Material and dimensions
Lamellae 2 components (PS, PA)
Bracket stainless steel
Height incl. mount 230 mm
Weight (without sensor) 700 g
Pole/pipe diameter for installation
horizontal (pipe) 3/4 ... 5/4 inch (27 mm ... 43 mm)
vertikal (pole/pipe) 1 ... 2 inch (27 mm ... 60 mm)
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