FnF – Flow/No-Flow Detector


The  FnF is a microwave-based mass flow switch. The electronics are mounted in the sensor head. The sensor measures completely reliably the mass flow of:

  • All moving powders
  • Grains

The FnF is available as a replacement for the Thermo Ramsey™ Granuflow (Model DTR & GTR).

Features – Easy installation

  • Easy to retrofit on existing pipelines
  • Detects moving particles only
  • Jumper-free circuit board
  • Configured using software
  • No need to open the sensor for setup – communicates with software via the sensor’s USB port

Measurement principle

The waveguide (stainless steel) conducts the microwave into the pipeline.
The microwave reflected by the particles is measured and analysed by an algorithm and converted into a proportional flow signal.
The flow meter is equipped with a relay switch.
The sensor emits a frequency of 24.125 GHz.


  • Windows-based
  • Sensor connects to PC via USB cable
  • Immediate insight into flow conditions in the pipeline
  • Graphical visualisation
  • Detects flow problems such as partially blocked rotating feeders
  • User-friendly interface in English, French and German

Dynascales Flow/no flow detector

  • Temperature stabilisation – normally only available on high-quality flow meters
  • Drift-free system
  • Large operating range – unaffected by pressure or temperature
  • 1 – standard FnF – replace the Ramsey GTR2 –
  • FnF with flange –  replace the Ramsey DTR
  • Power transmitter
  • Welded-on socket, stainless steel
  • M12 connection cable, 5 m, insulated
  • USB cable, 3 m
  • Software on USB stick
  • Crushing plants
  • Chemical plants
  • Asphalt plants
  • Mining
  • Cement plants
  • Coal and iron ore handling
  • Paper mills
  • Gypsum factories
  • Sand and gravel companies
  • Ore extraction
  • Loading and unloading facilities


Flow No Flow detetcor (FnF)
Power supply 24 VDC, IP66
Power Less than 0.4<br>At during warm-up ~0.35 A<br>after three minutes ~0.1 A
Measure frequentie K – band (24,125 GHz)
Pressure in pipe
Max. 8 bar, -20 C°-70C°
Enclosure Stainless steel and Aluminium

Do you have questions? Don’t hesitate to contact us!