Sonic anemometer, manufactured by RM Young.

Short Description

The RM Young sonic anemometer, model 8100, allows obtaining measurements of three wind velocity components and air temperature. The sonic anemometer operates by measuring a Doppler shift in sound propagation between tree pairs of transceiver/receiver prongs, highest possible sampling rate is 32 Hz.

This sonic anemometer requires 12 V power supply and is capable to provide the data trough serial (RS232) or/and analog (4 single ended channels of 0-5V) protocols.

Full manuals are on Internet or here.

Serial Configuration for the Sonic setup
1. Connect the serial flat D-Sub 9 Pins cable into one of two options:
a) RS232 Athen HUB
b) Computer port

Therefore, open the program HyperTerminal and load one of the following text files, accordingly to where the serial cable is connected:
a) sonic_aten2hub.zip
b) sonic.zip

For serial communication
Connect:
- pink to Tx, green to Rx and brown to sRef;
-Power: red to +, white to PwrRef, black to Earth
-Data: u (brown), v (orange), w (pink), T(blue).
Once you set the HyperTerminal program and connected the sonic, do the following:
1. Click on the computer screen.
2. Press Escape 3 times in a row quickly.
3. Click on S to setup.
4. Follow instructions pag.2 section 6 on Sonic manual

For analog communication with the sonic

Connect the sonic to the power supply 12-24 Volts.

Terminal 1 and 2 have to be connected to the + and - of the power supply.The terminal 3 has the cable shield connected to it. If using a power supply, it has to be connected to the ground of the power supply. If you use the DC battery, ground the terminal 3 on the body of the A/D.

Terminal (4-8) have to be connected to the A/D card. Terminals 4 to 7 represent the data:
4. Yellow is u;
5. Orange is v;
6. Blue is w;
7. Green is Temperature;
8. Brown has to be connected to the ground of the A/D card (COM).

Note: All the channels are single ended.

Noise issues
To minimize noise when operating on battery
Connect plus and minus to the battery. Then connect sonic ground output to A/D body. Finally, connect the shield of the cable to the AI ground in A/D card. MAKE SURE BATTERY NEVER FALLS BELOW 11.5V, can add this to code!!

To minimize noise when operating on power supply:
Connect plus, minus and ground to the power supply and add additional loop with ground to the A/D body for each sonic. Finally, connect the shield of the cable to the AI ground in A/D card.