The KOBOLD flow meter model DPE is used for measuring and monitoring liquids. The device works according the well-known blade wheel principle. The six vane blade wheel is retained axially in a highquality saphire bearing. The sensor is supplied ready-to-install with pipe fittings or with weld-on sleeves. The blade wheel is set in motion by the flowing medium. Magnets are embedded hermetically sealed in the ends of the blade wheels. The magnets generate electrical pulses in a Hall-effect sensor mounted outside the flow area.