WS-2 Premium Weather Station

The Davis GroWeather Wireless Integrated Sensor Suite is used for our WS-2 Premium Weather Station.6825_01_550x380 The corrosion-proof sensor suite combines a rain collector; solar irradiance, temperature and humidity sensors; and anemometer into one package for rugged reliability and performance. It features the Davis patented 24-Hour Fan-Aspirated Radiation Shield for maximum accuracy. It includes the Davis Vantage Connect Cellular radio for collection of the readings, typically every 15 minutes. The MyFarm web application displays current observations and calculates daily observations needed for irrigation management decisions.

Available Readings

  • Temperature
  • Relative Humidity
  • Rainfall
  • Solar Radiation
  • Wind Speed and Direction
  • Barometric Pressure
  • Dew Point

Specifications

Relative Humidity

Resolution 1%
Range 1 to 100%
Accuracy ±2%
Temperature Coefficient 0.03% per °F (0.05% per °C), reference 68°F (20°C)
Drift ±0.5%peryear

Rainfall

Resolution 0.01″ or 0.2mm (user-selectable) (1mm at totals ≥ 20000 mm)
Daily/Storm Rainfall Range 0 to 99.99″(0 to 999.8mm)
Monthly/Yearly/Total Rainfall Range 0 to 199.99″ (0 to 6553 mm)
Accuracy For rain rates up to 4″/hr(100mm/hr): ±4% of total or ± one tip of the
bucket (0.01″/0.2mm), whichever is greater.
Update Interval 20 to 24 seconds

Rain Rate

Resolution and Units 0.01″ or 0.1mm (user-selectable) at typical rates
Range 0, 0.04″/hr (1mm/hr) to 96″/hr (0 to2 438mm/hr)
Accuracy ±5% for rates less than 5″per hour (127mm/hr)
Update Interval 20 to 24 seconds

Solar Radiation

Resolution and Units 1 W/m²
Range 0 to 1800 W/m²
Accuracy ±5% of full scale (Reference: Eppley PSP at 1000W/m²)
Drift up to ±2% per year
Cosine Response ±3% for angle of incidence from 0° to 75°
Temperature Coefficient -0.067% per °F (-0.12% per °C); reference temperature = 77°F (25 °C)
Update Interval 50 seconds to 1 minute (5 minutes when dark)

Temperature (Outside)

Resolution 0.1°F or 1°F or 0.1°C or 1°C nominal (°C is converted from °F rounded to the nearest 1°C
)
Range -40° to +150°F (-40° to +65°C)
Sensor Accuracy ±0.5°F (±0.3°C)
Radiation Induced Error +4°F (2°C) at solar noon (insolation = 1040 W/m2, avg. wind speed  2 mph (1 m/
s)) (reference: RM Young Model 43408 Fan-Aspirated Radiation Shield)
Update Interval 10 to 12 Seconds

Wind Direction

Resolution
Range 0 to 360°
Accuracy ±3°
Update Interval 2.4 to 3 Seconds

Wind Speed

Resolution and Units 1 mph, 1 km/h, 0.4 m/s, or 1 knot (user-selectable). Measured in mph, other units are converted from mph and rounded to nearest 1 km/hr, 0.1 m/s, or 1 knot.
Range 1 to 200 mph, 1 to 173 knots, 0.5 to 89 m/s, 1 to 322 km/h
Accuracy ±2mph (2kts, 3km/h, 1m/s) or ±5%, whichever is greater
Update Interval Instant Reading: 2.5 to 3 seconds, 10-minute Average: 1 minute

Barometric Pressure

Resolution and Units Measured in 0.01″ Hg. Other units are converted from Hg and rounded to nearest 0.1 mm, 0.1 hPa, 0.1mb.
Corrected Range 26.00″ to 32.00″ Hg, 660 to 810 mm Hg, 880 to 1080 hPa or mb
Uncorrected Range 16.00″ to 32.00″ Hg, 410 to 820 mm Hg, 540 to 11100 hPa or mb
Elevation Range -1500′ to +15,300′(-46 0m to 4670 m)
Uncorrected Reading Accuracy ±0.03″ Hg (±0.8 mm Hg, ±1.0 hPa/mb)(at room temperature)
Sea-Level Reduction Equation Used United States Method employed prior to use of current “R Factor” method
Equation Source Smithsonian Meteorological Tables
Equation Accuracy ±0.01″ Hg (±0.3 mm Hg, ±0.3 hPa/mb)
Equation Accuracy Required ±10′(3m) to meet equation accuracy specification
Overall Accuracy ±0.04″ Hg (±1.0 mm Hg, ±1.4 hPa/mb)
Trend (change in 3 hours) Change ±0.06″ (2.0 hPa/mb, 1.5 mmHg) = Rapidly
Change ±0.02″ (0.7hPa/mb, 0.5 mm Hg) = Slowly
Trend Indication 5 Indicators: Rising (rapidly or slowly), Steady and Falling (rapidly or slowly)
Update Interval 1 minute

Solutions For Agriculture