Assembled from the most accurate individual sensors, the result is a high precision smart sensor and not just one device for all purposes. For different applications we have different combinations of the individual sensors.
Relative humidity is measured by means of a capacitive sensor element. The air temperature is captured by a precision NTC measuring element. Both sensors are integrated in an artificial ventilated radiation shield.
The air pressure is measured with an MEMS (micro electro mechanical system) sensor.
Ultrasonic sensor technology is used to take wind measurements. The integrated electronic compass can be used to check the north – south adjustment of the sensor housing for wind direction measurement. It is also used to calculate the compass corrected wind direction.
Radar technology is used to measure precipitation. The precipitation sensor works with a 24GHz Doppler radar, which measures the drop size and speed of every single drop (rain/snow) and calculates precipitation quantity and type by correlating drop size and speed. WS401-UMB and WS601-UMB are using an unheated rain gauge for precipitation measurement.
Optionally, the WS601-UMB and WS401-UMB can be equipped with a leaf wetness sensor in addition.
The global radiation is measured by a special adopted CMP3 pyranometer from Kipp&Zonen mounted in the top cover of the compact weather station WS501-UMB and WS301-UMB. Models WS502-UMB and WS302-UMB are equipped with a silicon pyranometer with very short response time.
All compact weather stations are equipped with a digital UMB (Universal Measurement Bus) output which corresponds electronically to an RS482, two wires, half duplex. The measurement output can be accessed by the following protocols: UMB-binary, UMB-ASCII as well as SDI-12 and Modbus.
Technical Data
Function
All sensors are integrated in a compact unit
The included sensors you will find in the selection table for the compact weather stations respectively
All stations are equipped with a digital output, optional a interface converter (RS485/RS232) as well as an digital/analogue converter for up to 8 values are available
All stations working maintenance free (except tipping bucket)
The measurement of temperature and humidity takes place in an artificial ventilated screen.
Sensors
Temperature
Principle: NTC
Measuring range: -50 ... +60°C
Resolution: 0.1 (-20...50°C)
Accuracy: ±0.2K (-20...50°C), otherwise ±0.5K
Relative humidity
Principle: capacitive
Measuring range: 0 ... 100% rel. humidity
Resolution: 0.1% rel. humidity
Accuracy: ± 2% rel. humidity (@0...90%)
Air pressure
Principle: MEMS capacitive
Measuring range: 300...1200hPa
Resolution: 0.1hPa
Accuracy: ±0.5hPa (@0..40°C)
Wind direction
Principle: ultrasonic
Measuring range: 0...359.9°
Resolution: 0.1°
Accuracy: ±3°
Wind speed
Principle: ultrasonic
Measuring range: 0...60m/s
Resolution: 0.1m/s
Accuracy: ±0.3m/s or ±3% 0...35m/s)
Compass
Principle: integrated electronic compass
Measuring range: 0...359°
Resolution: 1°
Accuracy: ±10°
Precipitation quality
Principle: Doppler radar
Measuring range: rain/snow
Precipitation intensity
Principle: Doppler radar or tipping bucket
Measuring range: 0...200mm/h
Precipitation quantity
Principle: Doppler radar
Measuring range: 0.3...5mm drop size
Resolution: 0.01mm
Reproducibility: typ. >90%
Precipitation quantity
Principle: tipping bucket
Resolution: 0.2mm / 0.5mm
Accuracy: ±2%
Leaf wetness (option)
Principle: capacitive
Measuring range: wet/dry
Global radiation
Principle: Thermopile Pyranometer
Measuring range: 0...1400W/m²
Spectral range: 300...2800nm
Resolution: 1W/m²
Accuracy: ISO second class
Global radiation
Principle: silicon cell
Measuring range: 0...1400W/m²
Spectral range: 300...1100nm
Resolution: 1W/m²
Configuration
with UMB Config Tool (supplied with station)
selection of sensors and calculated variables
selectable cycle time for averaging
administration of the energy management for the integrated heating
Firmware update
Test of the station
Communication
RS485, 2 wires, half duplex
UMB-Binary, UMB-ASCII, Modbus, SDI12
Supply
24V DC ±10%
power approx. 100W
Housing
plastic
IP66 / III SELV
Dimensions depending on the version diameter 150mm x 194mm up to diameter 164 x 445mm
