First you need to figure out the characteristics of the proximity switch: the proximity switch senses that the object is metal, and usually has a certain sensing distance and sensing frequency. These factors can affect the performance of the proximity switch. 1. Sensing distance: between 2mm-15mm, the longer the sensing distance, the larger the size of the proximity switch. Therefore, it is especially important to select the sensing distance for certain situations where installation factors need to be considered. 2, induction frequency: each type of proximity switch has an inductive frequency, such as: 500HZ, then more than this inductive frequency must use another A type of proximity switch. So when choosing the proximity switch, you need to consider the factors of the sensing distance and the sensing frequency according to the actual needs, and then determine what kind of approach to choose. switch.