Below are the answers to our most frequently asked questions. If you do not find the answer you are looking for here, then you can ask us a question by email or speak to an expert.


How do I place an order for sensors?

You can place an order by sending us an order form or by sending your purchase order direct to

If you are sending us purchase order directly, please remember to include the following information:

  • Company name
  • PO number
  • Invoice address
  • Delivery address
  • Contact name
  • Contact telephone number
  • VAT number
  • Quantity
  • Product part number

How can I arrange to trial a sensor?

If you would like to try out one of our sensors to see how it works in your particular project, then we can arrange for a sensor to be sent to you. After 180 days we ask you either to pay for the sensor, or return it to us sharing any data with us that you have collected over the trial period. To arrange a trial, please contact one of our commercial team.

Do you supply cables for power and data connection?

FT Technologies can supply small quantities of pre-assembled cables and connectors. For large volumes or long production runs it may be more economical to buy cables directly from your preferred manufacturer. You can see our full range of accessories here.

Can I speak to an engineer about my particular project?

Yes. Many people find it helpful to talk through the details of how they intend to use the sensor, in what environment, and how it will connect to their equipment. Our Applications Engineers are available Monday-Friday, 9-5.30 GMT. Alternatively, you can contact them by email and arrange a call back via Skype or telephone.

How much do your sensors cost?

We do not publish our prices online, but quote for each order individually. Our pricing is based on a number of factors including the exact product configuration and settings you require. This will depend on the application for which you will be using the sensor. Price is also affected by the volume ordered.

We will be delighted to give you a quick and free quotation for any of our products. If you would like to discuss your requirements with one of our Applications Engineers first, then please contact us.

How are FT sensors different to other ultrasonic anemometers?

What makes FT ultrasonic wind sensors unique is our use of Acoustic Resonance Technology. Invented by our Executive Chairman, Dr Savvas Kapartis, and patented in 1997, Acu-Res® is a solid-state (no moving parts) technology for measuring wind speed and direction. It uses an acoustic (ultrasonic) wave which is resonated inside a small cavity.

A strong resonating sound wave in a small space provides a large signal that is easy to measure. Acu-Res® has a signal to noise ratio more than 40db stronger than other ultrasonic technologies.

Using Acu-Res® technology results in a small, easily heated sensor which operates reliably, even under extreme weather conditions. The sensor's small size means that power is used very efficiently ensuring the that the sensor can stay ice-free. Small in size also means light in weight. The maximum weight of an FT7 Series sensor is 350g, and yet the hard anodised aluminium body makes the sensor incredibly strong.

The FT702 is probably the most tested wind sensor in the world. It has passed over 28 independent tests including sand, dust, ice, vibration, drop, corrosion, hail and lightning protection. The FT722 and the FT742 will undergo the same testing process before release. 

Essentially, Acu-Res® sets FT sensors apart from mechanical and other ultrasonic wind sensing technologies to give a more robust and reliable measurement solution.

Does the sensor only give readings in m/s or can I change it to km/h or knots?

FT7 Series wind sensors can output wind speed readings in m/s, km/h or knots. You can specify which option you would prefer at time of purchase. 

How can I test my sensor?

If you wish to test your sensor in real time then you should use an Acu-Test Pack which allows you to connect the sensor to a PC via a USB cable. It will give wind speed and direction readings in real time. It also allows you to change some settings such as heater set point temperature.

A serial emulator program (such as HyperTerminal) is another way of testing communication. This allows you to send  commands and receive messages serially to and from the sensor.  You can download HyperTerminal here. Please note, however, that FT Technologies is not responsible for the content of external sites.

Do you supply data-logging software?

We do not supply data-logging software however we do supply Acu-Test software that will provide readings in real time.

How can I protect my sensor from lightning strikes?

Wind sensors may be exposed to high levels of electromagnetic interference from static discharges and nearby lightning strikes. The FT7 Series incorporates robust protection circuitry to shield them against these effects. The FT7 Series wind sensors will survive undamaged even through lightning induced surges in excess of 4kA 8/20μs. 

The FT sensor is designed to survive indirect lightning strikes but, like any electrical equipment, it will not survive a direct strike. It is therefore essential that an appropriate lightning interceptor is installed with the sensor. The body of the sensor must be grounded along with the interceptor and grounding must be continuous through to the ground of the turbine or met mast on which the sensor is mounted. This is to ensure that the majority of the lightning current gets diverted away from the sensor.

The material of the mounting and lightning interceptor should be made from either high-grade aluminium or galvanised steel, due to their good conductive and anti-corrosion properties.

The sensor’s cable should have its shielding terminated at both ends – 360° terminated at the computer/datalogger end in the cabinet wall using an EMC cable gland. Signal wires should then pass through surge protection devices which must be correctly rated as per the Installation Section of the User Manual.

All mating surfaces must be free of non-conductive coatings and corrosion in order to ensure minimum resistance to ground.

FT Technologies can provide a lightning installation checklist which is designed to help you with checking that your sensor and computer/datalogger are adequately protected against lightning strikes. Contact us to request this checklist. If more in-depth technical advice regarding lightning protection is required (other than that which is available in FT technical material), then we would recommend contacting Global Lightning Protection Services in Denmark.

How can I ensure that my sensor will continue to work in an extremely cold climate?

Icing can be a problem for many wind sensors, particularly around 0°C where humidity levels can still be high. At lower temperatures the air tends to be drier so icing isn’t so much of a problem.

The FT wind sensor is highly resistant to icing due to its small size and effective heater. To get the best from your sensor in these conditions, the heater should be enabled and set to 30°C. If the default current limit of 4A proves insufficient then it can be raised in software to 6A but you must ensure that your power supply and cable can support at least 6 Amps.

The sensor should be mounted in such a way that heat can flow into the mounting itself. This helps to keep both the sensor and the mounting ice-free, thus ensuring that the sensor does not become ‘blinded’ by ice build-up. If icing could be an issue in your environment, then aluminium should be chosen for the mounting material, as this is a better thermal conductor than galvanised steel.

In very extreme conditions, the heater current limit can be increased from the default value of 4 Amps, to 6 Amps through software (in models with V22 and above). This will give a maximum power draw of 150W, however you should ensure that your cable and power supply is appropriately rated to handle the additional current.

How does the heater work and how can I configure it?

The FT wind sensor has a thermostatically-controlled intelligent heating system to control its three internal heaters. The heaters can be switched on or off, and a heater set point can be chosen between 0°C and 55°C (for v22 sensors and above). Earlier sensors have a maximum heater set-point temperature of 44°C.

In the case of the digital sensor, the heater set-point temperature can be changed through Acu-Vis software or manually, using the HT command via ‘Hyperterminal’. See the Command Parameters section of the User Manual for more details on this.

In the case of the analogue sensor, the heater set-point temperature can only be changed through the Setup & Test Program, using an FT055 cable. These are both supplied in the Acu-Test Pack.

FT can also pre-configure the heater settings for you before dispatching your sensor to you. If you would like to take advantage of this service, please specify your preference at time of ordering.

For most applications, FT recommends a heater set point of 30°C, as this ensures a consistent environment for the electronics and protects the sensor from sudden changes in ambient temperature.

As the heating system is thermostatically controlled, if the temperature of the sensor body rises above the heater set-point temperature, then the heater will automatically switch off. The heater circuitry only draws power when it needs it.

How do I change the settings on my digital sensor?

You can change the settings through HyperTerminal (or another serial emulator program), using the commands in the Command Parameters section of the user manual. You can download HyperTerminal here. Please note, however, that FT Technologies is not responsible for the content of external sites.

How do I change the settings on my analogue sensor?

The Setup & Test Program, supplied on your product CD (or included in the Acu-Test Pack, if you have purchased one) can be installed on a PC in order to communicate with the sensor. Through this software, you can view measurements in real time and also change the configuration of your sensor. To use this software, you will also require the FT055 cable (also included in the Acu-Test Pack) and a suitable power supply. To purchase an Acu-Test Pack for your sensor see our online accessories.

Does my sensor need calibration or maintenance?

All FT sensors are calibrated in our production wind tunnel and, unlike a mechanical sensor, the FT sensor has no moving parts. It will therefore maintain a consistent calibration throughout its lifetime. Periodic re-calibration is not required.

The sensor also has no user-serviceable parts and so does not require regular maintenance. We do however recommend that you carry out annual visual inspections to ensure that the cavity is clear of obstructions and that no corrosion has occurred between the sensor and its mounting.

If you wish to change the calibration of your sensor, then this is possible through the User Calibration Table feature of the sensor (available in models >V20 and not including FT702LM). See the User Manual for more details on this.

Can I get a calibration certificate for my FT sensor?

All FT sensors are calibrated in our own production wind tunnel. On request, we can supply the results of this calibration. Please contact us with the serial number of your sensor to request this service. If, however, a MEASNET calibration certificate is required, then contact us and we can recommend a suitable wind tunnel near you.

How can I stop my sensor showing erratic speed/direction readings?

There are several things that you should check if your sensor is showing erratic readings:

  • Ensure that your sensor is running the latest version firmware. Contact us to make sure that you have the latest version relevant to your sensor. You will need to quote your unit serial number when getting in touch.
  • Ensure that the heater set point is set to 30°C or higher.
  • Ensure that some sort of data averaging has been applied, either within the sensor (using the sensor’s internal filtering) or in the computer/data logger.
  • Check your cables are properly connected and ensure shielding is terminated at both ends of the cable. Refer to the Installation Section of your User Manual for further advice.

I have a sensor that I think is faulty. How do I return it for checking?

Please contact us to request a Returns Material Authorisation (RMA) form and provide the serial number of your unit, along with a detailed description of the symptoms you’re observing. We’ll then get in touch with instructions on what to do next.