Fast SFS and FS2 thermal mass flow sensors
Respirators and ventilators are currently in high demand, and accurate measuring results are of vital importanceEbnat-Kappel, )
Choose the right material
An inline flow sensor can be applied to monitor the flow through a cannula or mask and can be used to control the oxygen feedback loop. A simple and low-cost implementation was in mind during the development of the FS2 thermal mass flow sensor. While the SFS is made of silicon substrates, the FS2 is made of ceramic and glass which are inert, even if used in direct contact with 100% oxygen.
Other sensors and materials, FS7 and MFS02
During the development of the FS7, a simple implementation in combination with a robust and versatile material was achieved. The FS7 is also made of ceramic and glass (just like the FS2), however comes with only two resistors, which again allows an even simpler CTA (constant temperature anemometer) configuration when performing a flow measurement. For specialized applications, our MFS02 is made from polyimide and glass sensor construction materials.
Most modern ventilators can deliver flow rates between 60 and 120 L/min (which is 7 m/s with a 19 mm ID tube at peak flow). All sensor chips, the SFS, FS2, FS7 and the MFS02, cover a wide dynamic range and flow rates beyond the required flow volumes for a respirator application.