Applications of Pressure Sensors in Non-Negative Pressure Water Supply Systems

In modern urban water supply systems, non-negative pressure water supply systems have become an efficient and energy-saving solution. They cleverly utilize the existing municipal pipeline pressure while avoiding negative pressure impact, ensuring stable and reliable water supply for users. Pressure sensors, as core components, play a crucial role in monitoring and feedback. This article discusses the system principles, sensor roles, practical applications, and future trends, helping readers fully understand the value of this technology in water supply.

Basic Principles of Non-Negative Pressure Water Supply Systems

The non-negative pressure water supply system is an intelligent device directly connected to the municipal water supply network, designed to solve pressure fluctuations and negative pressure risks in traditional water supply. The system mainly consists of a regulating tank, pressure stabilizing tank, pump unit, control system, and various valves. When municipal water enters the regulating tank at a certain pressure, air in the tank is automatically discharged through the vacuum eliminator, ensuring the tank is full and sealed.

If the municipal network pressure and water volume meet user demand, the system supplies water directly through a bypass check valve, avoiding unnecessary energy consumption. When network pressure is insufficient, the system automatically activates the pump to supplement water. Pressure sensors monitor real-time changes in network pressure and send signals to the microcomputer controller to dynamically adjust compensation, achieving pressure balance.

This design complies with urban water supply regulations, which prohibit direct installation of residential or industrial pumps on municipal networks. By adding flow controllers and compartmentalized pressure stabilizing tanks, the system continuously monitors municipal network pressure, preventing negative pressure even during peak usage, thereby protecting the network.

Core Role of Pressure Sensors in the System

Pressure sensors serve as the "eyes" and "nerve center" of the non-negative pressure water supply system. Typically installed at key points in the supply network, such as pump inlets or near regulating tanks, they detect pressure fluctuations with high sensitivity. These sensors often use piezoresistive or capacitive principles, capturing subtle changes within milliseconds and converting signals into electrical data for the controller.

During operation, if water consumption increases and network pressure drops, sensors immediately feedback data, triggering pump startup or speed adjustment. If municipal water exceeds pump flow, the system maintains normal operation; otherwise, water from the regulating tank supplements supply, with air entering through the vacuum eliminator to prevent negative pressure. Sensors also link to level controllers, sending shutdown signals when water is too low to prevent pump damage.

Compared to traditional pressure switches or contact gauges, modern pressure sensors offer higher accuracy and stronger anti-interference capabilities, adapting to complex environments. For example, Nexisense's pressure sensors use advanced MEMS technology, with wide measurement ranges and excellent stability, proven reliable in many urban water projects. These sensors not only improve system responsiveness but also reduce maintenance costs, ensuring efficient and safe water supply.

System Workflow and Control Mechanism

The operation of the non-negative pressure system is a dynamic cycle. Municipal water first enters the regulating tank, with air expelled and tank sealed for use. During normal supply, the bypass check valve opens, directly utilizing pipeline pressure. When pressure is insufficient, sensors detect signals, and the controller starts the pump. While the pump operates, if municipal water is sufficient, balance is maintained; during peak periods with insufficient municipal water, the regulating tank supplements, while the vacuum eliminator introduces air to prevent negative pressure. If water drops below a threshold, the level controller stops the pump to protect equipment.

The entire process relies on microcomputer algorithms, with sensor data forming the decision basis. This closed-loop control ensures pressure remains within set values (e.g., 0.2–0.5 MPa) and adjusts according to user demand. In high-rise building renovation projects, introducing this system reduced pressure fluctuations during peak periods by over 30%, significantly improving user satisfaction.

Additionally, the system integrates flow controllers to monitor municipal network flow in real time, preventing over-extraction and negative pressure. Nexisense sensors support Modbus or RS485 protocols, enabling integration with PLC or SCADA systems for remote monitoring and data analysis, enhancing intelligence.

Advantages and Practical Applications of Non-Negative Pressure Systems

Compared with traditional tank or variable-frequency water supply, non-negative pressure systems have notable advantages: energy-saving (fully utilizing municipal pressure, reducing pump operation time, saving 20–50% electricity), water quality protection (avoiding secondary contamination, no storage needed), and easy installation (compact, suitable for old building retrofits).

They are widely applied in urban residential areas, commercial complexes, and industrial parks. For instance, a coastal city's high-rise residential project used Nexisense pressure sensors in a non-negative pressure system, resolving end-of-network pressure insufficiency, saving tens of thousands of tons of water annually, maintaining high stability, low failure rates, and extending maintenance cycles to once per year.

From an economic perspective, although initial investment is slightly higher, savings from energy efficiency and low maintenance quickly recoup costs. Policy-wise, China encourages promotion of such efficient water supply technologies to address water scarcity and urbanization pressures.

Potential Challenges and Solutions

Challenges include unstable municipal pressure or sudden supply interruption. Solutions include multi-level sensor monitoring and backup power design. Nexisense sensors have built-in diagnostics to provide early warnings. Proper installation ensures sensor accuracy and avoids vibration interference. Regular calibration every 6–12 months is critical to maintain precision.

Future Development Trends

With IoT and AI integration, non-negative pressure systems will become smarter. Pressure sensors may integrate wireless transmission for cloud-based data analysis and demand prediction. Nexisense is developing 5G-based sensor modules for real-time supply optimization. Eco-friendly materials and low-power design will drive green transitions. Under the Belt and Road Initiative, the technology may be exported to developing countries, supporting global water resource management.

FAQ

Which scenarios are suitable for non-negative pressure water supply systems? Urban high-rise buildings, residential communities, commercial sites, especially areas with stable municipal network pressure.

How to maintain pressure sensors? Regular cleaning and calibration, avoid extreme temperatures or corrosive environments. Nexisense provides detailed maintenance guides.

Installation considerations? Ensure compatibility with municipal networks, add flow controllers, and use professional teams.

Energy-saving compared to traditional supply? Average savings over 30%, depending on usage patterns and network conditions.

How to handle municipal water outage? Use regulating tank to supplement water and automatically stop pumps until supply resumes.

In summary, non-negative pressure water supply systems, with pressure sensors at the core, achieve efficient and reliable water supply, solving urban water challenges and demonstrating technology’s impact on improving lives. Choosing reliable brands like Nexisense further ensures performance. This field will continue evolving to support sustainable water use.