Design and Manufacture of Innovative Electronic Instruments and Controls for the Power and Gas Utilities Since 1978

WIND BEARING TRANSDUCER

0 to 360 Degree Scaling

Wind Bearing is usually described by the direction from which the wind is blowing. The eight common compass points, North, South, East, West, North-East, North-West, South-East, and South-West give general directional data, but more precise indications are expressed in the 360 degrees of a circle. As shown above, North is assigned zero degrees, and the degrees increase clockwise toward the east.

360 degree option

 Bearing = reading/Full scale count X 360

The WB can be ordered with one of two output options. The zero to 360 option is illustrated above. Note the slope is 1milliamp per 360 degrees. North is zero milliamps. The analog output increases as direction changes clockwise. South is 0.5 milliamps. As the analog output nears one milliamp, the direction is back to North again. The graph shows that both zero milliamps and one milliamp represent North. At North there is a discontinuity which can swing back and forth between zero and one milliamp, if the wind varies a few degrees around direct North. This is generally not a problem in the real world, but should be considered. Demico has a solution to this problem by using the 540 degree option. This option requires more programming capability from the computer, but delivers correct data at any bearing.