Inductive proximity sensors achieve reliable non-contact detection of metallic objects within a specified sensing range by interpreting the fluctuations created by the presence of a metal object within the nominal field of operation (which registers as a variation in the output of the sensor). How much variance depends on the size and material construction of the metal target, but this form of inductive proximity sensing is used extensively in industrial automated environments. Inductive sensor products from major-brand suppliers such as Omron, Pepperl+Fuchs, Ifm, Sick, Contrinex and others can be supplied from stock – with over 60% of items available for next day delivery. Sensing distance ranges from 0.6 mm to 60 mm with the majority functioning up to around 10 mm. A particular advantage of non-contact proximity sensors is that they remain unaffected by dirt and similar environmental challenges – for example some components can operate in temperatures down to -40 Centigrade, while others can withstand temperatures up to +100 Centigrade. Programmable options can be supplied (for instance offering NO or NC contact functions), plus a variety of common terminal connectors and durable shielded cables using tough PUR and PVR materials.