How Does a Liquid Pressure Sensor Work?

Liquid Pressure Sensor: Core Technology and Full Analysis of Industrial Applications

The Physical Foundation of Pressure Sensing: How Force Is Converted into Data

In automation control systems, liquid pressure sensors serve as the "outpost" for monitoring fluid conditions. Whether it's subtle fluctuations in urban water supply networks or massive pulses in industrial hydraulic systems, their core task is to precisely convert the physical pressure generated by fluids into processable electrical signals.

1. Diffused Silicon Piezoresistive Technology: NiuBoL's Core Choice

NiuBoL series pressure sensors primarily adopt advanced diffused silicon piezoresistive principle. The core is a highly sensitive silicon micromachined chip:

• Piezoresistive effect: When liquid pressure is transmitted through the stainless steel diaphragm and internal filled silicone oil to the silicon chip, the resistivity of the semiconductor material changes significantly with stress.

• Bridge conversion: The Wheatstone bridge on the chip converts resistance changes into millivolt-level voltage signals.

• Precision processing: The internal ASIC chip amplifies the raw signal, performs linearization correction and temperature compensation, and outputs standard industrial signals.

2. Structural Design to Handle Extreme Conditions

To ensure long-term operation in complex environments, NiuBoL liquid pressure sensors have undergone deep structural optimization:

• 316L stainless steel diaphragm: Excellent corrosion resistance and mechanical toughness, capable of withstanding most acid-alkali liquids and fluid erosion.

• Water hammer protection mechanism: For instantaneous ultra-high pressure pulses generated by pump start/stop, an optional micro-porous damping device inside effectively mitigates shock waves and protects the pressure-sensitive core from breakdown.

NiuBoL Liquid Pressure Sensor Technical Specifications Table

RS485 Digital Integration

In the trend of digital transformation, NiuBoL sensors achieve the leap from analog to digital information through standard RS485 interfaces, providing convenience for remote monitoring and big data analysis.

1. Advantages of Digital Protocol

• Lossless transmission: Digital signals have no voltage drop attenuation in long-distance transmission, with effective transmission distance up to 1200 meters.

• Intelligent networking: Dozens of NiuBoL sensors can be mounted on a single bus, significantly reducing wiring and I/O module costs.

• Self-diagnostic function: In addition to pressure values, users can also read device temperature and internal operating status.

Typical Application Scenarios of Liquid Pressure Sensors

1. Smart Water Supply and Constant Pressure Control

In secondary water supply pump stations, NiuBoL sensors provide real-time feedback on pipe network pressure. When water consumption increases and pressure drops, the frequency converter increases pump speed based on sensor data. Its high-frequency response ensures water pressure fluctuations remain within extremely small ranges.

2. Agricultural Automated Irrigation

Precision irrigation requires constant pipeline pressure to ensure uniform sprinkler coverage. NiuBoL sensors not only monitor pressure but can also determine filter blockage or pipeline rupture through pressure anomalies.

3. Liquid Level Measurement Based on Hydrostatic Principle

According to the physical law P = ρgh, NiuBoL submersible series can be directly used for depth monitoring in reservoirs and storage tanks. Special air-guide cable design automatically compensates for atmospheric pressure fluctuations, ensuring measurement accuracy is unaffected by weather changes.

Engineer's Recommendations: Installation and Wiring "Pitfall Avoidance" Guide

Even the most precise sensors rely on scientific installation. NiuBoL technical team has compiled the following engineering experience:

• Waterproof bend (U-bend) design: When wiring outdoors, the cable must reserve a downward U-bend to prevent rainwater from seeping directly into the sensor root along the cable.

• Avoid zero drift: After physical installation and fastening, perform electrical wiring. For micro-pressure sensors, changes in installation posture (vertical or horizontal) may cause slight zero offset; it is recommended to perform a "one-key zero" calibration via RS485 command after installation.

• Electromagnetic shielding: In sites with large frequency converters or motors, shielded twisted-pair cables must be used, and the shield layer must be reliably grounded at one end to eliminate high-frequency interference.

• Air venting and pressure relief: Before measurement, ensure no air remains in the pressure guide pipeline; otherwise, gas compressibility will cause sluggish data response.

Common Questions about Liquid Pressure Sensors (FAQ)

Q1: How to determine the required range?
A: It is recommended to select a range 1.5 to 2 times the normal operating pressure of the system. Too large a range sacrifices resolution; too small a range easily damages the diaphragm during instantaneous system overpressure.

Q2: Can NiuBoL sensors measure corrosive liquids?
A: Standard models use 316L stainless steel, suitable for water, oil, and weakly corrosive media. For strong acids, strong alkalis, or food-grade requirements, we provide ceramic diaphragm or flush diaphragm customized models.

Q3: What causes unstable RS485 signal transmission?
A: Usually due to lack of terminating resistors. For long-distance transmission (over 500 meters), please connect a 120-ohm resistor in parallel at the bus end and check for common-ground interference.

Q4: Why is there deviation in sensor readings in winter?
A: This is temperature drift phenomenon. NiuBoL sensors have built-in three-level temperature compensation algorithms, but if the ambient temperature exceeds the compensation range (-20℃~+85℃), external insulation measures are recommended.

Summary:

Liquid pressure sensors are not just simple pressure converters but the foundation of data acquisition in modern industrial systems. NiuBoL, through high-standard diffused silicon core selection, three-level temperature compensation process, and digitized Modbus RTU protocol, transforms fluid pressure into stable and transparent decision-making basis.

From the fields of smart agriculture to precision control in industrial production, NiuBoL always adheres to "industrial-grade reliability" as the standard, helping customers achieve the leap from "extensive monitoring" to "precise sensing".

If you are currently conducting system selection or facing complex pressure monitoring challenges, welcome to contact the NiuBoL technical support team at any time. We will provide you with comprehensive solutions from wiring definitions to cloud platform integration.