WIND SPEED & DIRECTION
|| ±0.3m/s (0-16m/s)
|| ±2% (16m/s-40m/s)
|| ±5% (40m/s-75m/s)
|Accuracy (within ±10° of datum):
|| ±2° RMS
|(beyond ±10° of datum):
|| ±4° RMS
These specifications are calculated with the default filter enabled.
INTERFACE and data format
Supply voltage: 20V to 30V DC (24V DC nominal)
Supply Current (heater off ): 31mA Typical. Supply Current (heater on) limited to 4A (default), 6A (max) configurable in software in 0.1A increments. Heater power
consumption will depend on the energy required to keep the sensor’s temperature at the user determined set point. The heater and sensor power consumption is limited by default to 99W.
I/O connector: 5-way (RS485 option), 8-way (4-20mA option) multipole connector
Sensor weight: 320g (max) for Flat Front variant
350g (max) for Pipe Mount variant
Interface: RS485, galvanically isolated from power supply lines and case
Format: ASCII data, polled or continuous output modes, NMEA 0183
Data update rate: 10 measurements per second.
Error handling: When the sensor detects an invalid reading a character is set in the wind velocity output message. This error flag character is a value other than 0.
Interface: 4-20mA, galvanically isolated from power supply lines and case
Format: One 4-20mA current loop for wind speed (different scaling factors are available). One 4-20mA current loop for wind
direction (datum value configurable as 4mA or 12mA). Both analogue channels are updated 10 times per second.
4-20mA configuration port: This port is for the user to change the internal settings of analogue sensors and to perform diagnostic
testing. This interface is not intended for permanent connection to a data logger or other device.
Error handling: When the sensor detects an invalid reading then both speed and direction current loops will drop to a default value of 1.4mA (configurable up to 3.9mA). If the sensor detects a wind speed of greater than 75m/s then the speed current loop will be set to 20.48mA and the direction current loop will be set to the error value – by default 1.4mA (configurable up to 3.9mA).
The sensor is fitted with a thermostatically controlled ‘all-body’ heating system. The sensor maintains its temperature at a user specified heater set point of between 0⁰C and 55⁰C. Three software controlled heaters are used to distribute heat intelligently over the entire sensor.
In standard format the heaters draw a maximum of 99W. For extreme environments the current limit can be adjusted (power supply and cabling permitting) from 0.1 to 6 Amps.
The sensor’s small size means that the power is used very effectively ensuring that the sensor can stay ice-free.
The FT742 ultrasonic sensor has passed over 28 certification tests, making it ideal for use in extreme climates. Theses tests include:
- Corrosion ISO 9227 (2006)
- Neutral Salt Spray IEC 12944 C5-M
Sinusoidal and Random Vibration EN 60068-2-6 and EN 60068-2-64
- Drop EN 60068-2-31
- Sand & Dust, Fog & Rain DEF STAN 00-35 CL25, CL26, CL27
- Ingress Protection IP66 and IP67
For full details see Product Certification.
In addition the FT702LT-V22 sensor is a Recognized Component by Intertek to the UL safety standard 61010-1 and CAN/CSAC22.2 No. 61010-1-04. As the FT742 is built to the same high standards as the FT702, we fully expect it to achieve this Intertek recognition soon.
The FT742 has also passed the FT Highly Accelerated Life Test (HALT) in which the sensor is temperature cycled from +125°C to -90°C whilst being vibrated at 30grms.