A differential pressure sensor is mainly used to measure the pressure difference between two pressure points and is widely applied in the following fields:

1. Flow Measurement: By measuring the pressure difference between two points in a pipeline, the fluid flow can be calculated. This is commonly used in industrial pipelines and liquid delivery systems.

2. Level Measurement: In tanks or containers, the pressure difference between the inside and outside of the liquid is measured to determine the liquid level.

3. Filter Condition Monitoring: By detecting the pressure difference before and after the filter, it helps to determine the filter's clogging status, ensuring normal system operation.

4. HVAC Systems: Used to monitor the pressure difference in air handling equipment or filters to optimize airflow and filtration efficiency.

5. Boiler and Steam Systems: Differential pressure sensors are used to monitor the pressure difference inside and outside the boiler, ensuring the system operates safely and efficiently.

These sensors are commonly applied in industries such as oil, chemical, pharmaceutical, and power sectors, for process control and equipment protection.

1. Capacitive Differential Pressure Sensor:

   - Measures the differential pressure between two points by detecting changes in capacitance. When the pressure difference changes, the distance between the capacitor plates inside the sensor varies, altering the capacitance value.

   - Features: High accuracy and good stability, suitable for precise industrial measurements.

2. Piezoresistive Differential Pressure Sensor:

   - Converts differential pressure into an electrical signal using the piezoresistive effect. When differential pressure acts on the sensitive element, the resistance value changes.

   - Features: Simple structure, fast response, suitable for medium to low-pressure environments.

3. Inductive Differential Pressure Sensor:

   - Measures differential pressure by detecting displacement changes in an inductive coil. The diaphragm inside the sensor moves under differential pressure, changing the inductance value.

   - Features: Suitable for harsh environments with strong anti-interference capabilities.

4. Resonant Differential Pressure Sensor:

   - Measures differential pressure by detecting changes in resonant frequency. When differential pressure acts on the sensor, the resonant frequency changes, allowing pressure difference measurement.

   - Features: High accuracy and long-term stability, suitable for high-precision applications.

5. Strain Gauge Differential Pressure Sensor:

   - Measures differential pressure by sensing diaphragm deformation using a strain gauge. The pressure difference causes slight deformation in the diaphragm, and the strain gauge converts this deformation into an electrical signal.

   - Features: Highly durable and suitable for high-pressure environments.

6. Thermal Differential Pressure Sensor:

   - Senses differential pressure by measuring the thermal effect of fluids, often used in gas flow and low-pressure difference measurements.

   - Features: Suitable for measuring small pressure differences, primarily used in gas detection.

These differential pressure sensors are widely used in various industrial fields, with different types being suitable for different working environments and accuracy requirements.