Sensors of the IFE family with a length of up to 900 mm are used to detect large metallic objects and offer a switching distance of up to 180 mm. The sensors are very robust, water-tight according to IP 68 and thus also suitable for outdoor use. The proximity switches are based on the proven inductive principle and switch con tactless when a metallic object moves close. Sensors of the family replace several inductive sensors connected in series. With their large sensor surface the reliably detect large moving metal parts. The sensors check for example the reinforcement in cast concrete parts during quality control or report the presence of railway rails for onward transport.