The FT702LT Series wind sensor powered by Acu-Res® technology has been carefully designed for turbine control. Its compact size and robust construction mean that it will give many years of reliable service despite the harsh conditions found on many wind farms. In design, development and manufacture everything possible is done to ensure that the product meets the demanding requirements of the wind turbine industry. The FT702LT Series provides wind turbine manufacturers and operators with a ‘fit and forget’ wind sensing solution. Every sensor is thoroughly tested before despatch and is calibrated in our own wind tunnel and no further calibration is required.

Turbine control – onshore and offshore

The sensor has no moving parts and does not need re-calibration. This reduces costly turbine down-time and maintenance visits. The sensor is well suited to offshore applications with the incorporation of enhanced protection to prevent corrosion from high levels of salt spray. The sensor has achieved a Class C5-M rating as recommended by the GL Renewables Guidelines for the Certification of Offshore Wind Turbines 2012 (Section 7.11.4). For operation in ice-prone areas both onshore and offshore, the FT702LT Series is fitted with a highly effective thermostatically controlled heating system. A three element heater (one element located in the top of the sensor and two in the bottom) helps to keep the sensor ice-free. The sensor has passed the demanding US military icing test MIL-STD-810G. Further independent tests to recognised standards show that the sensor can withstand random and sinusoidal vibration, physical impact, lightning and EMC. The sensor has also passed a hail test with 25mm hailstones hitting it at 23m/s.

The FT702 range of wind sensors powered by Acu-Res® technology is designed to give many years of reliable service in a wide variety of environments. In design, development and manufacture everything possible is done to ensure that the product is reliable, accurate and consistent. The sensor has no moving parts and does not need re-calibration. This eliminates the costs of inspection and re-calibration. The FT702 range delivers a ‘fit and forget’ wind sensing solution with a low total cost of ownership. The aluminium hard anodised body is highly resistant to corrosion, sand and dust and is sealed to IP67 standard. The aluminium body ensures that heat is evenly distributed for effective ice prevention. For detailed product certifications please refer to the relevant datasheet. Every sensor is thoroughly tested before dispatch and is calibrated in our own wind tunnel and no further calibration is required.

Low Power

With the heaters switched off the sensor draws only 25mA at 24 volts DC. However it can also run at 12 volts making it ideal for use with batteries. At voltages below 11V the sensor continues to operate but the heaters are automatically disabled. This means that in areas subject to icing a voltage based control system can be designed to switch on the heaters by raising the voltage above 11V – this enables the heaters and then they will operate at the chosen heater set point. Maximum current draw can be left at the default of 4A or set to a lower figure. This will reduce the drain on the batteries although it will of course limit the effectiveness of the heaters. Contact us for further advice on power and heater management strategies.

Product range

The FT702LT V22 is the latest version of the sensor and it can be supplied with either RS485 or Analogue 4-20mA output. It can be mounted on a pipe using the specially designed FT mount adapter FT089. The FT702LM range is designed to be mounted directly on top of a piece of equipment. When mounted with the supplied mounting gasket it delivers an installation sealed to IP67. The FT702LM2 is fitted with a compass. All FT sensors can be specified at time of order to output data in knots.