QUESTION: Our requirement is 120 units of anemometers and 60 units of wind vanes. IEC 61400-12-1 specifies clearly that no other instrument shall be positioned closer than 1.5 meters vertically from the anemometer cups and the wind vane shall be mounted at a minimum of 1,5 m below the primary anemometer. Moreover we install anemometers and wind vanes at different heights. Does MeteoWind 2-in-1 wind speed & direction sensor satisfy this requirement as they will measure at almost same height.
ANSWER: This IEC 61400-12-1 requirement was written before the MeteoWind 2 wind sensors were developed. Further, MeteoWind is a single wind sensor measuring wind speed and direction and not two separate instruments as IEC 61400-12-1 assumes.
As logic would suggest, measuring wind speed and wind direction together at a single point creates much more meaningful data which can more accurately quantify turbulence and wind shadow effects of masts and wind turbines.
As you can imagine, if a customer installs 120+60 MeteoWind 2, their data quality, data density, and data redundancy will be significantly higher than with separate installations of wind vanes and anemometer at the same total cost.
Click here for a detailed MeteoWind 2 anemometer datasheet with a MEASNET certificate.