The magnetic proximity switch is a non-contact sensor based on the Hall element. It not only has the characteristics of no contact, long sensing distance, no switch transient jitter, high reliability and long life, but also has a strong load capacity. And a wide range of functions. At the same time, overheat protection, surge protection, polarity protection, and short circuit protection can make the magnetic proximity switch work in a harsher environment. It has stronger anti-interference ability than the inductive, capacitive, photoelectric and other proximity switches currently used. . In view of the many advantages of magnetic proximity switches, magnetic proximity switches occupies a considerable proportion of the proximity switches currently on the market. They are widely used in the measurement of physical quantities such as rotation speed, displacement, position, and speed.