A non-contact proximity sensor — typically Hall-effect or reed-switch type — used in elevator shaft to detect vane position for floor levelling, door zone, and speed-reduction switching.
Full Definition
Elevator magnetic sensors (inductance proximity sensors or magnetic proximity switches) are installed along the shaft to provide the controller with precise position information. Hall-effect sensors output a digital signal when a ferrous or magnetic vane attached to the car enters the sensor field (typical switching distance 5–20 mm). They are used for: (1) floor-level detection and re-levelling (levelling vane ± 5 mm); (2) door zone signal — authorises door opening only when car is within ± 200 mm of floor level (EN 81-20 §5.3.6.2); (3) slow-down (deceleration) zone initiation at terminal floors; (4) end-of-travel limit switch triggering. Reed switches are used in some older or lower-cost installations with permanent magnet vanes. Modern systems may use optical or capacitive sensors but magnetic types dominate due to robustness in dusty, humid shaft environments. Sensors must comply with EN 81-20 §5.11 regarding safety-related electrical components; those in the door zone circuit must meet safety integrity requirements.
