Ultrasonic Anemometer 2D | Theodor Friedrichs & Co

2D Ultrasonic Anemometer

In cooperation with MESA Systemtechnik GmbH we are proud to present our 2D Ultrasonic Anemometer. The new 2D Ultrasonic Anemometer is designed for simultaneous measurement of horizontal wind speed and wind direction parameters as well as the acoustic temperature, without use of any moving parts. It is equiped with the latest technology and is air-flow optimized with the help if air-flow simulation software. The result is a very precise, durable and multi-functional sensor.

Its construction features a wide range of applications in meteorology, environment protection and industrial applications, e.g. with automatic weather stations, airports, research vessels, industrial plants, mobile systems etc.

Thanks to its robust design and its optional heating, the type 4310 is suitable particularly for heavy duty tasks, such as wind energy measurement or measurement under extreme climatic conditions. Various simultaneously available outputs enable a high degree of flexibility in use.

Type 4310 measures horizontal wind speed and wind direction, resp. wind vector parameters by means of 2 orthogonally placed measuring tracks. Wind vector components x and y, as well as the acoustic temperature are determined from sonic pulses runtime measurement.

Horizontal wind speed and wind direction are calculated from these vectors. The temperature value is derived from the sonic speed and is therefore not identical with the regular dry temperature, measured by a thermometer, but comes close to the meteorological virtual temperature, considering the humidity content.

The sonic velocity depends on the air density (scalar value) and the interfering wind speed (vectorial value). By calculating the difference of runtime between way there and way back, scalar values (temperature, humidity, density) are eliminated and the result comprises wind speed, only. By calculating the addition of runtime, on the other hand, the wind speed is eliminated, so that the “acoustic” temperature can be determined. This temperature, however, also depends on the ambient air pressure and humidity. For sea level conditions, it may be assigned to the “virtual temperature” which considers the relative humidity, hereby resulting in values 1…2.5 K above those obtained from an ordinary “dry” thermometer. Basing on this principle, the wind components are measured independent from ambient air pressure, air temperature and relative humidity, while the acoustic temperature varies with these parameters.

The calibration parameters are not influenced by aging, as there are no moving mechanical parts involved. As well, all further disadvantages from mechanically moving cup anemometers and wind vanes are avoided. Operation under ice conditions is realized by optional built- in heating devices.

Technical Specification

Variations

Measuring Range Wind Speed: 0...40 m/s, 0...75 m/s, 0...85 m/s
Accuracy Wind Speed: v ≤ 5 m/s: ± 0.1 m/s (rms over 360°)
v > 5 m/s: ± 1.5 % of measurement value (rms over 360°)
Resolution Wind Speed: 0.1 m/s or 0.01 m/s, depends on telegram type
Starting Threshold Wind Speed: 0.1 m/s
Measuring Range Wind Direction: 0...359°
Accuracy Wind Direction: ±0.6° RMS (at v = 8 m/s), ±1° absolute
Resolution Wind Direction: 1° or 0.1°, depends on telegram type
Measuring Range Virtual Temperature: -55...+70° C
Accuracy Virtual Temperature: ±0.5K (at v > 0.6m/s)
Resolution Virtual Temperature: 0.1K or 0.01K, depends on telegram type
Digital Interfaces: RS422 (full duplex) / RS485 (half duplex), selectable
(Bus mode with 99 participants possible);
CAN/CANopen
Analog Interface: 0...20 mA / 4...20 mA or 0...10 V / 2...10 V,
reely selectable for Wind Speed and Wind Direction;
Voltage: load > 1 kΩ; Current: load < 700 Ω;
Frequency out up to 2000 Hz for wind speed
Baud Rates: 1200...115200 Baud, selectable
Formats: 8 Data, Odd, Even or No Parity, One Stop Bit
Update Rates (Instantaneous/Avg.): 0.000278..100 Hz (10 ms to 60 min),
selectable for Wind Speed, Direction and Virtual Temperature
Output Rates: 0.0167...1000 Hz (1 ms to 60 s), selectable
Units : m/s, knots, kph, mph, ft/min
Parameters: Polar, NMEA, TEMP, see manual chapter 6
Status: Heating, Internal voltage error, Blocked measurement track, ΔT track deviation, plausibility
Internal Sample Frequency: 2000 Samples / s at +20°C
500 measurement values / s at + 20° C
Operating Temperature: -40°...+70°C
-55°...+70°C (with additional body heating)
Housing: Material: Stainless steel V4A
Weight: 1.4 kg
Protection Class: IP67
Qualifications: EMC DIN EN 61000-6-2:2005
EMC DIN EN 61000-6-3:2007 + A1:2011
Icing resistance MIL STD 810G
Blowing sand AECTP 300
Corrosion DIN 9227
Vibration/Shock IEC 60068-2-64/-6/-27/-29
Solar irradiation DIN EN 60068-2-5
Freefall / Drop IEC 60068-2-32