SCHMIDT® flow sensors with ATEX certificate

For Zone 2 and Zone 22

For applications in potentially explosive areas, upon request the thermal flow sensors 20.500 from SCHMIDT Technology are available in Ex designs according to ATEX Directive 94/9/EC (ATEX 95) for use in flammable media.

Their patented dumbbell makes the SCHMIDT® flow sensor SS 20.500 predestined for use in dust-containing air and aggressive gases. However, these atmospheres are often also potentially explosive, which gives rise to additional requirements that the systems, units and components must meet in such environments. For these applications, SCHMIDT Technology offers the SS 20.500 in 'Ex' design. They conform to ATEX Directive 94/9/EC (ATEX 95 and 100a) and meet the ATEX requirements according to category 3 for Zone 2 (gases and vapors) and Zone 22 (dusts). To this end, special protective functions have been integrated, such as the protective sleeve for the plug-in connector of the connecting cable and the grounding terminal on the housing. For difficult mounting situations, the version with remote sensor, i.e., separated from the electronic housing, is recommended. Both components can be used on their own in Zone 2 or Zone 22 and are connected directly to the power supply without a Zener barrier. In the remote version, additional grounding is done on the sensor tube. If an SS 20.500 Ex is used in free flow, the so-called intrinsic safety with limited power supply to the sensor ensures that no ignition spark can be formed when the sensor becomes damaged or breaks. The suitability of the SS 20.500 Ex according to the above-mentioned directive was determined and certified by the external test institute DEKRA EXAM GmbH.