Swiss made with first class materials


No mobile parts and no obstructing possibility

Very low power consumption

Ultra-optimized acoustic sensing

SDI-12 and IoT compatible

Also compatible to all other common I/O standards


Lifetime, CE certification and Packaging

HailFlow sensor

The extremely robust and reliable HailFlow HF4 sensor is a highly specialized acoustic instrument for the detection of hail and the characterisation of hailstone size.

  • Non obstructable

  • Instrument with no mobile parts – totally sealed acoustic instrument

  • Universal mounting kit available

  • Omni-directional – even under the highest winds

  • Corrosion free and resistant to the highest winds and the most extreme conditions

  • Plug-and-Play or totally configurable – microcontroller inside

  • Can be connected to almost any external unit

  • SDI-12 and IoT compatible – internal memory

  • Swiss made


  • High resolution hail monitoring and warning
  • Roadside, railway, airport protection
  • Building and infrastructure surveillance and insurance
  • Maritime and offshore applications (wind turbines, buoys)

Documents & download:

Please download here the original ISAW-Toolbox software suite, for any model of your sensor.

The ISAW-Toolbox software suite is an all-in-one toolbox utility that allows fully configuring and operating your sensor.

You can download the ISAW-Toolbox software suite in two ways:

  • use the standard setup installer (.exe, .dpkg),
  • or download the non-intrusive standalone archive (.zip, .bz2).

Select the package that match your Operating system (Windows, Linux or Mac) and system architecture (32 or 64 bits), download the package.

To use the installer (.exe, .dpkg): Click on the downloaded file and follow the installation process.
From the archive (.zip, .bz2): Unzip the downloaded file and click on the utility you need.”

.exe .zip
isaw toolbox win32 isaw toolbox exe32
Soon :

The HailFlow HF4 sensor:  an ultra-robust instrument

It is a very low-power, maintenance-free and totally sealed acoustic instrument with no mobile parts.

The instrument includes a dedicated analog conditioning module, a digital I/O module and an analog restitution module that can be connected conveniently to almost any external central unit (data logger, industrial module interface, instrumentation DAQ, USB port).

It features continuous or pulse analog voltage outputs and supports SDI-12 communication, serial RS-232, and Modbus RTU RS485 (using an optional adapter).

The sensing part of the instrument is a three layers polished stainless disc supported by an unbreakable stainless-steel arm. Impacts of hailstones (or any other lithometeors in the same range of kinetic energy) induce a measurable change in internal acoustic pressure.

The sensor is able to distinguish between 15 classes of hailstone diameter, ranging from 0.5 to 8 cm, with a capability of counting up to 25 solid impacts per second.

The full configuration of the sensor can be customized at any time, in a non-volatile memory, with a Plug-and-Play computer connection thanks to the universal USB dongle accessory provided with the sensor and the free ISAW-Toolbox software suite.