These limit switches, among the first ever designed to be used in environments with risk of explosion, allow to extend also to classified areas all forms of machine automation (and/or process) in total safety complying with the ATEX Directive. Limit switches are normally used as detectors of the relative position of moving parts, coordinated to each other (eg: by automation systems such as smart wired logic, dedicated microprocessors and PLC) or as elements associated with automatic devices for protection and safety for operators and machinery (e.g. alarm and shutdown intrusion, penetration, collision, presence systems, etc.).

Limit switches can be mechanic or magnetic; in the former, the movement of the limit switch, or of another element in relative motion, moves a piston or lever to produce the actuation of an electrical circuit of any kind. The magnetic switch takes advantage of the effects produced by the interference of a stranger metal item in a normally stable magnetic circuit. The “proximity”, with no contact, of the metal item alters the magnetic field of the sensor, providing the actuation of an electrical circuit.