Proximity sensor manufacturers said that for different materials and different detection distances, different types of proximity sensors should be selected to make them have a high performance-price ratio in the system. For this reason, the following principles should be followed in the selection:
1. When the detection body is metal material: Proximity sensor manufacturers believe that high-frequency oscillation type proximity sensor should be selected, which is the most sensitive to detection of iron-nickel and A3 steel detection bodies. For aluminum, brass and stainless steel detection bodies, the detection sensitivity is low.
2. When the detection body is a non-metallic material: Proximity sensor manufacturers believe that capacitive proximity sensors should be used, such as wood, paper, plastic, glass and water.

3. When metal bodies and non-metals are to be detected and controlled remotely: Proximity sensor manufacturers believe that photoelectric proximity sensors or ultrasonic proximity sensors should be selected.
4. When the detection body is metal but the sensitivity requirements are not high: Proximity sensor manufacturers said that an inexpensive magnetic proximity sensor or a Hall-type proximity sensor can be used.
Elements of proximity sensor manufacturers selection:
① Detection type: Amplifier built-in type, amplifier separated type; ② Shape: round, square, groove type; ③ Detection distance: in mm; ④ Detection object: iron, steel, copper, aluminum, plastic, water, ⑤ Working power supply: DC, AC, AC and DC common; ⑥ Output form: normally open (NO), normally closed (NC); ⑦ Output mode: two-wire, three-wire (NPN, PNP); ⑧ Shield, Unshielded; ⑨ lead-out type, connector type, connector relay type; ⑩ Response frequency: several objects can be detected in one second.