Differences between ultrasonic wind sensors and mechanical sensors

When selecting a suitable wind sensor for an automatic weather station or wind measurement system, the different characteristics of ultrasonic and mechanical wind sensors need to be weighed.

Mechanical strength is an important consideration when selecting a wind sensor. While ultrasonic wind sensors are more robust due to the absence of moving parts, mechanical wind cups and vane sensors are also quite durable and can only be damaged by extremely strong winds, such as hurricanes exceeding 234 kilometres per hour. In addition, flying objects that may accompany strong winds may also damage the sensors.

When selecting a mechanical wind sensor, you need to consider its performance in cold and frosty environments. In extremely cold climates, the accumulation of snow and ice may break the rotor and wind vane of the wind sensor. Electrically heated wind sensors are available on the market, but they consume a lot of electricity and are not ideal for systems that rely on battery or solar power.

Sonic wind sensors are recommended when very low wind speed environments need to be measured. They are more sensitive than wind cup and vane sensors, especially for low wind speed measurements. In addition, acoustic sensors respond quickly to sudden changes in wind speed, making them also suitable for assessing the strength and duration of wind gusts.

Ultrasonic wind sensors are much easier to install; they do not require very precise horizontal mounting like cup and vane sensors. Therefore, the structure supporting the ultrasonic sensor does not need to be strictly horizontal, whereas cup and vane sensors must be mounted horizontally to ensure accurate measurements.

If the wind speed and direction sensors are separate, then two fixed structures and two cables are required to feed into the collection system. In contrast, ultrasonic wind sensors require no additional mounting fittings and only one cable to connect to the acquisition unit.