These pages describe an elegantly simple vector anemometer. It is an accurate and reliable standalone instrument for general use and has features which simplify its use in more complex applications.
The LED dials display wind speed to within a knot or so and wind direction within a few degrees. Pressing the pushbutton displays maximum gust speed and direction. Holding the pushbutton down resets these.
Web-based weather servers and other computers can read the wind data directly from its RS232 port. Its RS232 port can be connected to a modem, allowing remote wind monitoring via a dialup line.
The built-in data logger records speed and direction distributions and so stand alone it collects and stores the data for wind power site assessment.
One sensor measures both speed and direction and the downlead is general purpose twinlead. This reduces cost and improves reliability.
The Rotorvane for Windows package allows you to read and save current and logged data from a DIY Rotorvane Anemometer, and to plot wind speed and direction in real time. The anemometer can be either directly connected to the computer RS232 port or connected via modem. This package (and the VB source code) can be downloaded free of charge from our site.
RotorvaneTM technology was developed by Dr Derek V Weston between 1984 and 1990.
From 1991 until 2011 constraints consequent to a licencing agreement with Raymarine Ltd inhibited disclosure of details of the invention. These constraints no longer exist. You may use the information in these pages in any way and for any purpose including personal or corporate commercial benefit, but please give credit where credit is due.