Featuring internal diameters of 5, 12, 22, 25, 30, 44, 63 and 100 mm. Adjustable sensitivity, LED function indicator and short circuit & reverse polarity protection are standard. Most models available with pre-wired cable or connectors. Environmental protection is IP65: dust tight and protected against water jets. CE marked in conformity to 89/336 EEC and 73/23 ECC. In inductive ring sensors the sensing area is located inside the ring. These sensors are designed to detect metallic masses entering or passing through the ring. They are ideal for sensing, counting and checking of small metal part such as: screws, washes, nuts etc. and the control, detection, position, inspection and automation of machine tools & manufacturing systems. They are sealed in a rugged, plastic housing with a protection degree of IP 65. All versions have short circuit and reverse polarity protection and are available in both prewired cable or connector output connection. The operating principle is based on a high frequency oscillator that creates an electromagnetic field in the close surroundings of the sensing surface. The presence of a metallic object (actuator) in the operating area causes a decrease of the oscillation amplitude. Part of the electromagnetic energy is transferred from the sensor to the actuator and is dissipated. The oscillation amplitude is then identified by a threshold circuit that changes the output state. The operating distance of the sensor depends on the actuator shape and size and is strictly linked to the nature of the metal.