These electronic devices, photoelectric sensors or photocells use the light emission principle combined with the electronic and are made up of an emitter or luminous source, the light rays of which are detected by a receiver. The variation in the luminous signal obtained when interrupting this way is converted into an electrical signal and is measured and used by an electrical circuit. The light used is either infrared or red. By making use of this light various type of photoelectric sensors can be made. The Teknic Euchner photoelectronic sensors are available in direct reflection with reflector, with polarised light emitter-receiver version. Due to their flexibility regarding the various standard programmable versions, these products offer the possibility of stock reduction and are easily interchangeable with most of the units available in the market.