Proximity Sensors are available in models using high-frequency oscillation to detect ferrous and non-ferrous metal objects and in capacitive models to detect non-metal objects. Models are available with environment resistance, heat resistance, resistance to chemicals, and resistance to water.
(1)Proximity Sensors detect an object without touching it, and they therefore do not cause abrasion or damage to the object.
Devices such as limit switches detect an object by contacting it,but Proximity Sensors are able to detect the presence of the object electrically, without having to touch it.
(2) No contacts are used for output, so the Sensor has a longer service life (excluding sensors that use magnets).
Proximity Sensors use semiconductor outputs, so there are no contacts to affect the service life.
(3) Unlike optical detection methods, Proximity Sensors are suitable for use in locations where water or oil is used.
Detection takes place with almost no effect from dirt, oil, or water on the object being detected. Models with fluororesin cases are also available for excellent chemical resistance.
(4) Proximity Sensors provide high-speed response, compared with switches that require physical contact.
For information on high-speed response, refer to Explanation of Terms.
(5)Proximity Sensors can be used in a wide temperature range.
Proximity Sensors can be used in temperatures ranging from -40 to 200°C.
(6) Proximity Sensors are not affected by colors.
Proximity Sensors detect the physical changes of an object, so they are almost completely unaffected by the object's surface color.
(7) Unlike switches, which rely on physical contact, Proximity Sensors are affected by ambient temperatures, surrounding objects, and other Sensors.
Both Inductive and Capacitive Proximity Sensors are affected by interaction with other Sensors. Because of this, care must be taken when installing them to prevent mutual interference. Care must also be taken to prevent the effects of surrounding metallic objects on Inductive Proximity Sensors, and to prevent the effects of all surrounding objects on Capacitive Proximity Sensors.
(8)There are Two-wire Sensors.
The power line and signal line are combined. This reduces wiring work to 2/3 of that require for Three-wire Sensors. If only the power line is wired, internal elements may be damaged. Always insert a load.