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Davis Anemometer

Davis Anemometer
Image Copyright Davis Corporation

Overview

The Davis Anemometer (Part Number: 07911) is designed to measure both wind speed and direction. The wind speed sensor uses a magnetic reed switch that is triggered once per revolution of the wind cups. The wind direction is measured using a potentiometer. Both of these outputs are connected back through a 4 core 12 meter (40 feet) cable.

Specifications

Range
  • Wind Speed: 1 to 200 mph, 1 to 173 knots, 0.5 to 89 m/s, 1 to 322 km/h
  • Wind Direction: 0° to 360° or 16 compass points
Accuracy
  • Wind Speed: ±2 mph (2 kts, 3 km/h, 1 m/s) or ±5%, whichever is greater
  • Wind Direction: ±7°
  • Wind Run: ±5%
Resolution
  • Wind Speed: 1 mph (1 knot, 0.1 m/s, 1 km/hr)
  • Wind Direction: 1° (0° to 355°), 22.5° between compass points
  • Wind Run: 0.1 m (0.1 km)
General
  • Cable Type: 4-conductor, 26 AWG
  • Connector: Modular connector (RJ-11)
  • Recommended Maximum Cable Length: 140' (42 m) Sensor to Console
Material
  • Wind Vane and Control Head: UV-resistant ABS
  • Wind Cups: Polycarbonate
  • Anemometer Arm: Black-anodized aluminum
  • Dimensions: 18.5" long x 7.5" high x 4.75" wide (470 mm x 191 mm x 121 mm)
  • Weight: 2 lbs. 15 oz. (1.332 kg)

The cable supplied with the anemometer came with a RJ-11 connector. In all situations we have used this sensor we have cut the RJ-11 connector off the cable and connected to the individual wires. Of course if you were connecting to a Davis Weather Station you would not do this.

Davis Anemometer Interface Pinouts

The wind speed circuit is essentially a switch circuit with two resistors to limit the current flow.

Davis Anemometer Wind Speed Circuit

The wind direction is measured using a potentiometer attached to the shaft of the wind vane. This will generate a variable voltage level to the output pin.

Davis Anemometer Wind Direction Circuit

This is the actual circuit used by the Davis anemometer. It is a combination of the two circuits above. Davis Anemometer Wind Speed Direction Circuit

Connect Arduino to Davis Anemometer