The main categories of pressure switches include normally open and normally closed. The main features are:

1. Adopting the British style pipe thread quick connector or copper pipe welding installation structure, the installation is flexible, easy to use, and does not require special installation and fixation.

2. The plug-in wire type connection can be freely selected by users.

3. Sealed stainless steel sensor is safe and reliable.

4. Manufacturing can be carried out within the pressure range according to the pressure value selected by the user.

A pressure switch is a device that is combined with an electrical switch. When the pre-set fluid pressure is reached, the switch contact will activate. It is mainly used for outputting alarm or control signals on industrial equipment such as power plants, petrochemicals, and metallurgy industries. It has important applications in the industrial field and can prevent damage to important devices in production engineering, avoiding major production accidents.
2. Main sensitive components of pressure switch 2.1 Bellows
Features: It has better durability and vibration resistance than Bourdon tubes, with a large adjustable range of connection and disconnection differences. The main materials are stainless steel, phosphor bronze, etc. The price is relatively high, but the measurable pressure range is small, up to 40MPa (CB33) 2.2 diaphragm
Features: It has excellent corrosion resistance and is mainly made of materials such as NBR and fluororubber. Sensitive components such as CS and CL series are also used. The selection of pressure switch quick and easy automation is included.

Classification of pressure switches

flameproof type

Pressure switches can be divided into explosion-proof and explosion-proof types, with a usage level range of Exd II CT1~T6. Imported explosion-proof pressure switches must pass UL, CSA, CE and other certifications. Can be used in explosive areas and environments with strong corrosive atmospheres. Explosion proof pressure switches can provide products with different pressure, differential pressure, vacuum, and temperature ranges. The common application scope includes industries such as electricity, petroleum, chemical, metallurgical, boiler, food machinery, environmental protection equipment, etc.

Mechanical type

Mechanical pressure switch, caused by pure mechanical deformation resulting in micro switch action.

When the pressure increases, it acts on different sensing pressure components (diaphragm, bellows, piston) to deform and move upwards. Through mechanical structures such as railing springs, the micro switch at the upper end is finally activated to output electrical signals. The setting method of UE pressure switch can be divided into continuous displacement type and force balance type based on functional principles.

Electronic type

Another popular option in the market in recent years is electronic pressure switches, which are used to replace electric contact pressure gauges and in systems with high industrial control requirements. This pressure switch is equipped with a precision pressure sensor, which amplifies the pressure signal through a high-precision instrument amplifier and collects and processes the data through a high-speed MCU. Generally, it uses a 4-digit LED real-time digital pressure display, relay signal output, and upper and lower limit control points that can be freely set. It has low hysteresis, anti vibration, fast response, stability and reliability, and high accuracy (generally within ± 0.5% F.S, and up to ± 0.2% F.S). The use of hysteresis setting can effectively protect the repeated actions caused by pressure fluctuations, protect the control equipment, and is a high-precision device for detecting pressure and liquid level signals, realizing pressure and liquid level monitoring and control. The characteristics are: intuitive electronic display screen, high precision, long service life, convenient setting of control points through the display screen, but relatively high price, requiring power supply.

working principle

The working principle of a pressure switch is that when the pressure inside the system is higher or lower than the rated safety pressure, the disc inside the sensor instantaneously moves, and the switch joint is connected or disconnected by the connecting guide rod. When the pressure drops to or rises to the rated recovery value, the disc instantly resets, and the switch automatically resets. In other words, when the measured pressure exceeds the rated value, the free end of the elastic element displacement, directly or after comparison, pushes the switch element to change the on/off state of the switch element, achieving the purpose of controlling the measured pressure. The elastic components used in pressure switches include single coil spring tubes, diaphragms, bellows, and corrugated tubes.