Application Pressure switch adopts the pressure sensor with high precision and high stability performance and the converter circuit, and through the modularized signal processing technology of special CPU, it realizes the detection, display, alarm and control signal output of medium pressure signal. Structure Pressure switch is a device combined with an electrical switch that switches contact action when the preset fluid pressure is reached. 1. Adopt quick joint of inch pipe thread or welded copper pipe installation structure, which is flexible in installation and easy to use without special installation and fixation. 2. The plug type wire type connection can be arbitrarily selected by the user. 3. Sealed stainless steel sensor is safe and reliable. 4. The pressure range can be manufactured according to any pressure value selected by the user. Operating Principle When the pressure in the system is higher or lower than the rated pressure, the safety of the sensor in the disc instantaneous movement, through the connecting rod to push switch connector on or off, when the pressure drop to or the raising of the rated value, the instantaneous reset disc, switch automatic reset, or simply, when the measured pressure exceeds rating, displacement of the free end of the elastic element, directly or after comparison switch element, change the on-off state switching element, achieve the goal of measured pressure control. The elastic elements used for pressure switch include single coil spring tube, diaphragm, film box and corrugated tube.