Rugged anemometer survives shake, rattle, and cold

Cup anemometers can lock solid if the icing conditions are right. But a recent non-cup design from Lufft Ventus showed it can withstand extreme vibration, corrosion, heat, and extreme ice conditions. You might think the so-called HALT test is intended to destroy a wind sensor because it pushes that unit to limits of heat, cold, vibration, and corrosion. One Ventus unit survived the punishing test that includes temperatures exposures from -95 to 95°C along with maximum vibration and corrosion portions. Manufacturer Lufft says it has plans to improve the sensor so it tolerates -120 to 120°C.

This particular wind sensor uses ultrasonics which work well in most extreme conditions. The HALT test is unusual in that it exposes a device to extreme corrosion while vibration, heat, and cold is produced in a special wind tunnel that generates high velocity wind towards the sensor simultaneously in three vector directions.

The wind sensor is intended for turbine control anemometry. Resistance to ice is possible with a 240W heater, and resistance to corrosion comes from a heavy duty anodized aluminum alloy. IP65 will assure the sensor resists water intrusion in the strongest storms and offshore environments. The company’s rugged wind sensor comes in several flexible communication options including current or voltage. Each sensor is configurable with free software by Lufft. A copy of the HALT test report is available by request from Lufft.

High survivability is critical for wind sensors installed on today’s large and small wind turbines. Labor cost is high so project owners cannot afford wind-sensor relate down time. View the Ventus video at:  http://www.lufftusa.com/video/ventus1.html

Lufft

Weather assessment? Not a problem

A manufacturer of climate-monitoring devices has a new product for weather assessment. Santa Barbara-based Lufft USA will add MODBUS, a data protocol, to its list of communication standards. The protocol lets many devices connected to the same network communicate. One example is a system that measures temperature and humidity and transmits results directly to a computer or programmable logic controller.

Lufft says the protocol is often used to connect a supervisory computer, sensor, or group of sensors with a remote terminal unit in supervisory control and data acquisition (SCADA) systems. Sensors that communicate by MODBUS are commonly used in renewable energy, building automation, and other industrial processes. The company says the addition of this common method of industrial communication to its list of digital protocols will let its weather stations measure climate parameters with almost any industrial project.The company’s ‘WS’ line of weather stations is available with the data protocol in addition to SDI12, ASCII, UMB, NMEA, and analog.

Lufft USA www.lufftusa.com

12 month study to compare data quality, sensor reliability in cold climates

Cup anemometers or ultrasonic versions: Which works best where icing is worst? That is the questions to be answered after a 12 month study by Windpole LLC.

Windpole Ventures LLC of Arlington, Mass. has teamed with Garrad Hassan Americas to conduct a twelve month comparative study of ultrasonic and cup anemometers. The test will take place at locations in Illinois, Iowa, and Indiana, where winter-anemometer icing can be severe.

Both sensors will be unheated during the test. Boom configuration will be standardized and recommended by the third-party engineering firm. Tests will use a Lufft ultrasonic unit from LUFFT USA, which promises to address the problem of cup damage from falling ice and lost data as ice freezes sensors. The Lufft is armored, affordable, and can be heated.  “Ultrasonic sensors seem expensive at $1,000 to $1,500 per unit,” says WindPole CEO Steve Kropper. “A cup anemometer with a calibration certificate may cost just $350. But we look at life-cycle costs over five years. As soon as a cup sensor fails, that “cheap” anemometer looks expensive.” Industry standard cup (mechanical) anemometers were chosen for this study to reflect ‘industry standard’ for wind assessors in the US.

After the field study, Garrad Hassan will submit a complete analysis of the results. The results will be queried on three parameters.

1)    Data-quality comparison. Does data produced from ultrasonic sensors track that of the ‘industry standard’ mechanical sensors?

2)    Ice resistance during icing events

3)    Common failure causes for mechanical and ultrasonic units

While mechanical (cup) sensors are the commonly accepted technology in the wind industry, the precision and maintenance free aspects of ultrasonic sensors make them attractive to the wind assessment field especially in applications requiring real-time data. The National Weather Service upgrade from mechanical to ultrasonics started an industry trend. However, the IEC proscribes mechanical sensors for use in wind assessment. Time, research, and experience will show how the industry will accept growing use of ultrasonic technology.

Automated weather station can come with datalogger

The WS line of weather stations (including the economical WS200 ultrasonic anemometer) are now available with built in SDI-12 communication protocol, says LUFFT USA. Its weather stations and anemometers are now plug and play with any SDI-12 ready datalogger.  Lufft Intelligent Weather Stations and Anemometers still have the same function of an intelligent digital sensor, but now with more flexibility. For example,  the company offers its sensors with a Campbell Scientific datalogger as a new turnkey wind and weather assessment package.

Dataloggers from Campbell Scientific, widely used throughout the wind industry, can be programmed using Loggernet for use with Lufft sensors, which are also available with heaters.

Intelligent wind sensors from LUFFT USA are reliable and maintenance-free ways to measure wind and weather. The WS series of compact intelligent weather sensors (WS200 to WS600) along with VENTUS and V200A models measure different atmospheric parameters to meet specific weather monitoring needs. The top-of-the-range model, WS600-UMB, measures temperature, humidity, precipitation, air pressure, wind direction and wind speed.