Inductive proximity sensor
Phoenix America

The inductive proximity sensor is one more item in the massive line of sensor packages used in industrial automation. In this case, they are usually connected to a relay or PLC to provide sensing as part of a larger automated process. The major advantage of an inductive proximity sensor (often called a prox switch, although this is really a generic term for any sensor that detects objects close to it without physical contact) is the fact that it ignores nonmetallic objects. This is useful for positioning metal parts, such as conveyors, lift tables, tipples, and machine parts, while ignoring any nonmetallic objects around, such as the goods being manufactured or packaging material like cardboard boxes or loading pallets, or the operator running the machine.

The second advantage of an inductive proximity switch is that, due to the way it ignores most substances, it can get very dirty and still work properly. This, combined with their solid state circuitry and wear-free operation due to not making physical contact with the object it senses, allows them to provide years of nearly maintenance-free operation.