uSonic-3 Class A

Model Number: uSonic-3 Class A
Manufacturer: METEK Meteorologische Messtechnik GmbH
Product Brochure: Download

Research grade 3-AXIS Ultrasonic Anemometer for measuring wind speed and direction. Separate head designed for minimal flow distortion and boom mounting.


uSonic-3 Class A

The uSonic-3 Class A 3-axis ultrasonic anemometer is the most accurate and advanced sensor in the Metek product range. It has been designed for small scale turbulence measurement or mast instrumentation. The separate sensor head is optimised for boom type installations and the minimisation of influence from the sensor hardware. The sensor head is configured for minimal flow distortion within a wide acceptance angle of 320°.

With options for on-line turbulence calculations, sensor head heating, inclination sensor, and the connection of external sensors the uSonic-3 Class A provides the best possible accuracy for research applications and can be used as a core component of an eddy-flux / eddy correlation station.


  • minimal flow distortions across a wide angular range
  • separation of the sampling head to reduce flow distortions
  • high accuracy due to generic 2D and 3D wind tunnel calibration
  • 50 Hz sampling rate with 2D corrections
  • 30 Hz sampling rate with 3D corrections
  • wind speed range 0.01 – 40 m/s (0-90 mph)
  • verifies and reports data quality
  • raw data outputs available
  • sonic temperature measurement -40°C – +70°C
  • low power consumption (5W, 9-36Vdc)
  • 6m separation of measurement head and control electronics
  • option – inclination sensor
  • option – on-line turbulence calculations
  • option – analogue outputs
  • option – for up to 6 analogue inputs, 2 PT100 inputs and 2 TTL inputs
  • option – sensor head heating
  • optional mains power supply
  • optional field calibration kit

Technical Description

The uSonic-3 Class A provides the following information in various data outputs which can be polled or output automatically:

  • instantaneous and averaged data for the three component wind vectors
  • virtual temperature
  • horizontal wind speed and direction plus vertical wind component
  • chart mode (provides 0-540º wind direction and speed values)
  • NMEA value outputs
  • raw data mode (uncorrected) or 2D / 3D head corrected data

Data can be averaged by:

  • scalar or vector
  • clock synchronised or running average
  • separate output rates and sampling times

Separation of the sensor head and control electronics:

  • reduced flow distortions due to less equipment around the area of measurement
  • more flexibility in mounting of the measurement head
  • 6m cable for connection between measurement head and control electronics

Some other important features:

  • user definable north orientation (range 0-359º alignment off axis)
  • data quality control to perform confidence checks on raw data
  • date / time stamps with several options
  • check sum information
  • calibration validity output monitoring

Near real-time turbulence calculations available as an option:

  • mean wind components (3D) and temperature
  • Standard Deviations (SD) of components and temperature
  • covariances of different components and temperature
  • SD values comparing mean wind to parallel component as well as the horizontally and vertically perpendicular wind component
  • turbulence intensities
  • friction velocity
  • Drag coefficient
  • Monin-Obukhov stability
  • momentum and heat fluxes
  • u, v, w
  • direction and velocity mean components or values

Technical Specifications

Wind Speed
Range 0.01 - 40 m/s (0 - 90 mph)
Accuracy 7.5cms/s or +/- 1.5 %
Resolution 0.01 m/s (steps)
Wind Direction
Range 0 - 359°
Accuracy +/- 1.5°
Resolution 0.1° (steps)
Digital Output
Type RS422, RS485
Sampling rate 50 Hz (with 2D corrections), 30Hz (with 3D corrections)
Averaging up to 3600 seconds
Units of measure m/s, knots, mph, km/h, °C
Internal Memory 15,300 standard samples or 2600 turbulence data sets
Sonic temperature -40°C to 70°C in non-condensing environments
Head separation 6m cable between sensor heat and control electronics
IP rating IP65
Size 32 cm x 69 cm (12 x 27 inches)
Weight 7.1 kg (15 Ibs)
sensor head stainless steel (V4A)
electronic housing powder-coated die-cast aluminium
Requirements 9-36 VDC
Current draw 180 mA (@ 24 VDC), 5W
Online turbulence calculation Extensive online turbulence calculations with near real time output. See above for details of available parameters
Analogue inputs Options available for six high precision voltage inputs, two PT100 and two TTL inputs
Analogue outputs Option available for four scalable analogue voltage outputs. 0-5V/±5V, 0-10V/±10V or 0-2.5V/±2.5V 12 Bit, scalable
Sensor head heating Heating of the sensor head, 100W
Mains Power Supply Weather proof mains power supply available for either 110 or 240 Vac. Supplies power for both the sensor electronics and the optional heating
Calibration kit A calibration kit is available to check the accuracy of the sensor in the field
Power and Data Cable Power and data cable can be provided ready terminated at user defined lengths

Sales & Support

Contact Biral for more information

To find out more about this instrument or to discuss your application requirements please do not hesitate to contact Biral.

  • email (or use the Request More Information button below the product photograph)
  • Telephone to 01275 847787 (from the UK) or +44 1275 847787 (International)

After Sales Support

Biral offers free advice and technical support for the lifetime of the instruments we sell. Once you have purchased the unit you can always contact us for help using the links on our Technical Support page.