CSAT3

3-D Sonic Anemometer
CSAT3

CSAT3

Retired

3-D Sonic Anemometer

No longer available to order

This product is retained for service, documentation, and compatibility information.

Replaced by

  • CSAT3B

    3-D Sonic Anemometer with Integrated Electronics

Model:
CSAT3
Item Number:
R_8900
Warranty:
1 year

Overview

The CSAT3 is a three-dimensional sonic anemometer that measures three orthogonal wind components and the speed of sound. In eddy covariance systems, it can measure the turbulent fluctuations of horizontal and vertical wind. These measurements are then used to calculate momentum flux and friction velocity. This sonic anemometer can also provide average horizontal wind speed and direction measurements. The CSAT3 comes with 25 ft cables.

Key Advantages

Precision Measurements
Best instrument for flux and
other high-level turbulence
research projects

Technical Description

The CSAT3 has a 10 cm vertical measurement path and operates in a pulsed acoustic mode. The three orthogonal wind components (ux, uy, uz) and the speed of sound (c) are measured and output at a maximum rate of 60 Hz. Analog outputs and two types of digital outputs are provided.

Measurements can be triggered from from the CSAT3’s internal clock, the PC-generated RS-232 command, or the data logger’s SDM command. The SDM protocol supports a group trigger for synchronizing multiple CSAT3s.

The FW05 fine wire thermocouple (12.7 μm diameter) is available as an option for fast response temperature measurements.

Benefits

  • Provides precision turbulence measurements with minimal flow distortion
  • FW05 fine wire thermocouple (12.7 μm diameter) is available as an option for fast response temperature measurements
  • Withstands exposure to harsh weather conditions
  • Measurements can be used to calculate momentum flux and friction velocity
  • Compatible with most Campbell Scientific data loggers

Specifications

Measurement Path Length
10.0 cm

(3.94 in.) vertical

5.8 cm

(2.28 in.) horizontal

Path Angle from Horizontal
60°
Construction
Sealed sonic transducers and electronics
Anemometer Head Materials
Stainless-steel tubing
Electronics Box Materials
Cast aluminum
Operating Temperature Range
-30° to +50°C
Voltage Supply
10 to 16 Vdc
Current
200 mA

(60 Hz measurement rate)

100 mA

(20 Hz measurement rate)

Digital SDM Output Signal
CSI 33.3 k baud serial interface for data logger/sensor communication.

(Data type is 2-byte integer per output plus 2-byte diagnostic.)

Support Arm Diameter
1.59 cm

(0.63 in.)

Transducer Diameter
0.64 cm

(0.25 in.)

Transducer Mounting Fingers Diameter
0.84 cm

(0.33 in.)

Cable Length
7.62 m

(25 ft)

Anemometer Head Dimensions
47.3 x 42.4 cm

(18.6 x 16.7 in.)

Anemometer Head Weight
1.7 kg

(3.7 lb)

Electronics Box Dimensions
26 x 16 x 9 cm

(10.24 x 6.3 x 3.54 in.)

Electronics Box Weight
3.8 kg

(8.4 lb)

Measurements

Outputs
ux, uy, uz, c


(ux, uy, uz are wind components referenced to the anemometer axes; c is speed of sound.)

Speed of Sound
Determined from three acoustic paths; corrected for crosswind effects.
Measurement Rate
Programmable from 1 to 60 Hz, instantaneous measurements.

Two over-sampled modes are block averaged to either 20 Hz or 10 Hz.

Measurement Resolution
Resolution values are for instantaneous measurements made on a constant signal; noise is not affected by sample rate.
1 mm/s rms

(ux, uy)

0.5 mm/s rms

(uz)

15 mm/s (0.025°C) rms

(c)

0.06° rms

(wind direction)

Offset Error
Offset error and gain error values assume the -30° to +50°C range, wind speeds of < 30 m/s, and wind angles between ±170°.
< ±8.0 cm/s

(ux, uy)

< ±4.0 cm/s

(uz)

Gain Error
Offset error and gain error values assume the -30° to +50°C range, wind speeds of < 30 m/s, and wind angles between ±170°.
< ±2% of reading

(wind vector within ±5° of horizontal)

< ±3% of reading

(wind vector within ±10° of horizontal)

< ±6% of reading

(wind vector within ±20° of horizontal)

Wind Direction Accuracy
±0.7° at 1 m/s

(for horizontal wind)

Rain
Innovative ultrasonic signal processing and user-installable wicks considerably improve the performance of the anemometer under all rain events.

Digital RS-232 Output Signal

Baud Rate
9600, 19200 bps
Data Type
2-byte integer per output plus 2-byte diagnostic

Analog

Number of Outputs
4
Voltage Range
±5 V
Number of Bits
12

SDM & RS-232 Digital Outputs Reporting Range

Full-Scale Wind
±65.535 m/s autoranging between four ranges

(Least significant bit is 0.25 to 2 mm/s.)

Speed of Sound
300 to 366 m/s

(-50° to +60°C) Least significant bit is 1 mm/s (0.002°C).

Analog Outputs Reporting Range

ux
±30 m s-1, ±60 m s-1
uy
±30 m s-1, ±60 m s-1
uz
±8 m s-1
c
300 to 366 m s-1

(-50 to +60°C)

Analog Outputs LSB

ux
15 mm s-1, 30 mm s-1
uy
15 mm s-1, 30 mm s-1
uz
±8 m s-1
c
16 mm s-1

(0.026°C)

Common Accessories

(7)

Replacement Parts

(10)

Compatibility

Data Logger Considerations

Required Operating Systems or PROMs
Data Logger Model Data Logger Operating System (OS)
or PROMs Required
CSAT3 OS Required
21X 1K 6145-3, 6146-5, 10006-1 2.1 or higher
21X 2K 6148-5, 6149-7, 6070-64 2.1 or higher
CR800, CR850 All OS 3.0 or higher
CR10 2K 5954-396;
4K is a Library Special
2.1 or higher
CR10X OS 1.4 or higher 2.1 or higher
CR1000 All OS 3.0 or higher
CR23X All OS 2.1 or higher
CR3000 All OS 3.0 or higher
CR5000 All OS 3.0 or higher
CR9000 2.01 or higher 2.1 or higher
CR9000X All OS 2.1 or higher

Related Resources

Services Available

Repair
No
Calibration
Yes
Free Support
Yes