Explanation of the criteria for classification and numbering of components     C79.2.06
(JUN 00)
Explanation of the dates on the component's description



1.   Purpose and objectives

     To measure the water current speed without contacting the water surface.

2.   Description

     The Radio Water Current Meter is designed for remote measurements in situations that require that there be no contact between the measuring equipment and the water surface. It measures the water current speed by detecting the change in frequency of the reflected radio wave from the surface of water current. Typical measuring sites include rivers, irrigation channels and drainage sluices. A major feature is that it can be used to measure current speed at sites with high water levels and rapid currents, frequently changing river beds, and currents that are harsh as a result of pebbles, debris, and objects in the water.

     The range of speeds measured is 0.5m/s -10m/s with an accuracy of 1% of full scale.

3.   Input

     Actual water current.

4.   Output

     The instrument provides an analogue signal in the range of 0V-1V DC, a digital output on an RS-232C port and a digital display.

5.   Operational requirements and restrictions

     The instrument uses a 10.525 GHz radio wave and this will require registration with the radio frequency allocation authorities. A regulated power supply is required. Water waves on the surface of the current are needed to ensure good reflection of the radio waves. The instrument must be within 20m of the water surface.

6.   Form of presentation

     A catalogue and instrument specifications are available.

7.   Operational experience

     About 10 sets were installed in Japan in 1999.

8.   Originator and technical support

     Yokogawa Denshikiki Co.,Ltd.

9.   Availability

     From the HOMS National Reference Centre for Japan.

10.  Conditions on use

     Hardware is for sale.


(First entered: 01 FEB 93

Last updated: 21 APR 00)