Can clamp-on probes be used for permanent measuring?

Yes, definitely. The lack of knowledge around non-intrusive probes may lead people to think that they are not suitable for permanent installations and are only used for occasional measurements. This is not true and restricts the possibilities offered by clamp-on probes. For several years, Ultraflux has been combining fixed flow meters with clamp-on probes. To do this, the installation is created using a polymer coupling medium, which, in a few days, literally sticks the probe to the pipe. This makes it unnecessary to regularly change the coupling medium.

Does Ultraflux offer an after-sales service?

The company develops and manufactures in France the flow meters that it sells. As a result, it has an after-sales service team that can offer assistance on all of the previously designed flow meters, even those from more than 20 years ago. You can find the contact details for the after-sales service team here.

On a related note, you may be interested to know that Ultraflux has an engineering department available to activate and study any project you may have. Please do not hesitate to contact our sales team (+33 (0)1 30 27 27 30 / ultraflux@ultraflux.fr) for further information.

Is flow rate measurement using “ultrasonic transit time” technology suitable for natural streams?

Definitely. The principle of measuring flow rate using ultrasonic transit time difference is one of the more precise ways of measuring flow rate in ongoing real time on a river. Our customers estimate that the precision of our devices is around 2% at both low and high water levels. Our sales team and engineers would be happy to carry out any preliminary study of your application.

What are the main factors that influence the measurement precision of an ultrasonic flow meter?

According to the type of probes used (intrusive, clamp-on or wetted), the measurement precision depends mainly on the following criteria:


  • Hydraulic conditions and available straight lengths upstream and downstream. These lengths vary depending on the number of chords we have on the pipe or structure (to measure speed). As a general rule, we recommend 10D upstream and 5D downstream of an elbow. Our devices can be used to measure 8 speeds (8 chords = 16 probes). In this scenario, a few D’s would suffice.
  • Knowledge of the pipe’s dimensions (external diameter, thickness, material, etc.) if clamp-on probes are used. To satisfy this requirement, almost all of our flow meters can be delivered (as an option) with a thickness gauge.

Please remember that some information, such as celerity, gain, quality index, the Reynolds number and, on some models, the echo display, all make it possible to obtain high quality measurements.

Which operating systems can be used with Ultraflux’s PC software?

The PC software provided with Ultraflux equipment (flow meters and detectors) runs on all Microsoft Windows 32-bit and 64-bit operating systems.

Do the devices need to be calibrated regularly?

The calibration of your devices depends entirely on the quality policy in force in your organisation. Our flow meters are only managed digitally, which means that the components are never out of calibration. Furthermore, our measurement principle is not subject to any mechanical wear. As such, it is not necessary to return the flow meters to the factory on a yearly basis.

If an internal procedure requires you to calibrate your flow meter on a regular basis, we can offer several solutions:


  • a manufacturer’s check using a “small diameters” (22 mm or 40 mm) bench, non-COFRAC certificate,
  • or a COFRAC certificate (3 double points or 5 triple points) carried out by our partner.
How do I know which equipment is best for my application?

Our technical-sales engineers are at hand to guide you through the choices of equipment suited to your project. Equipment advice can only be given once the specific features of your application are known. For this purpose, you will be asked to fill in an information form giving as much details as possible.
You can request a quote over the phone (+33 (0)1 30 27 27 30) or directly here.

The following elements are just some of the criteria we take into account when choosing the device that is best suited to your application:


  • type of device desired (fixed or portable),
  • type of application (full pipe or free surface flow),
  • type of fluid (liquid or gas),
  • diameter or width of the pipework or structure,
  • material of the pipework or structure,
  • nominal flow,
  • desired accuracy, etc.
Is it possible for someone to come and give me a demonstration of the equipment?

The company Ultraflux has perfect knowledge of all of its measuring instruments, as do the technical sales engineers or distributors who present the equipment. They would therefore be delighted to visit you to pre

What is the recording length offered by the Ultraflux portable measurement devices?

Ultraflux currently manufactures and sells two portables flow meters: the Minisonic P and the Uf 801P.

The Minisonic P does not have an internal logger but can be connected to an external recorder (on one of the current outputs). The external recorder in question has 32,000 variables and its recording speed varies from 1 second to several hours.

The Uf 801P is equipped with a 4 Mo internal recorder, which is equivalent to 135,000 variables. It has the advantage of being able to record 14 parameters (including average flow rate) at the same time.

Do Ultraflux measuring devices work on all types of fluid?

Absolutely. The technology used by Ultraflux flow meters and detectors enables any type of clear fluid to be measured using ultrasounds. This applies to both liquids (homogeneous and monophasic) and gases (depending on the pressure and type of pipe). For further information on the fluids that can be measured using our equipment, please do not hesitate to contact us by phone (+33 (0)1 30 27 27 30) or email (ultraflux@ultraflux.fr).

I created a password for the keyboard of my flow meter and I have forgotten it. What can I do?

Request a temporary password from the Ultraflux after-sales service team via email (sav@ultraflux.fr), including the serial number (xx/xx/xxxx) and date displayed on the screen of your device. You will then be provided with a temporary password to access your device. Make sure that you use the temporary password as soon as you receive it, however, as it is only valid on the day on which it is issued.

Is it possible to hire a flow meter or detector? Does Ultraflux have a device hire service?

Yes, Ultraflux has a measuring device hire service. One model is available for hire: the Uf 801 P portable ultrasound flow meter. However, our detectors are not available for hire. For further information on the possibility of hiring a flow meter, please refer to our “Hire” page or give our sales team a call (+33 (0) 1 30 27 27 30).

What pipe diameters are covered by Ultraflux measuring devices?

Currently, Ultraflux equipment is capable of taking measurements, using clamp-on probes, on pipes with diameters of between 6/8 mm (may vary depending on thickness and material) to 10,000 mm as long as the flow range complies with our measurement principle. For more information on Ultraflux device options, please do not hesitate to contact our sales team (+33 (0)1 30 27 27 30 / ultraflux@ultraflux.fr).