Constant Pressure Water Supply: Principles & Key Instruments
Constant Pressure Water Supply Systems: Principles, Devices, and Applications
Introduction
Constant pressure water supply systems are widely used in modern water infrastructure—from residential buildings and commercial plumbing to wastewater treatment facilities and municipal booster stations. These systems automatically regulate water flow to meet real-time demand while maintaining a consistent outlet pressure.
This guide explains the working principle of constant pressure water supply and highlights three essential pressure measurement instruments commonly used in these systems.
How Constant Pressure Water Supply Works
The core idea behind constant pressure supply is simple: when water demand increases, the system delivers more water while keeping the pressure steady; when demand decreases, the system reduces flow accordingly. This dynamic control is often achieved using a variable frequency drive (VFD) combined with real-time pressure monitoring.
Key Pressure Instruments in Constant Pressure Systems
1. Remote Indicating Pressure Gauge
A low-cost mechanical gauge often used in legacy systems.
Pros: Affordable, simple to install
Cons: ±1.5% accuracy, poor vibration resistance, no digital output
Best suited for basic or non-critical applications, though increasingly replaced by digital alternatives in modern systems.
2. Diffused Silicon Pressure Transmitter
Widely used in industrial water systems and commercial buildings, these transmitters provide reliable pressure data with ±0.5% full-scale accuracy.
Advantages:
- Compact, lightweight design
- Stable output for long-term control
- Compatible with SCADA systems
They are ideal for integration into automated control loops and perform well in high-demand environments.
3. Electric Contact Pressure Gauge
A hybrid solution combining measurement and control.
Function: When pressure exceeds preset thresholds, internal contacts trigger alarms or start/stop pumps via relays or VFDs.
Application: Offers redundancy in case of VFD failure, preventing overpressure scenarios.
Conclusion
Constant pressure systems depend on accurate, responsive pressure monitoring. Whether you choose a traditional gauge or an advanced transmitter depends on your system's complexity and performance goals. For automated, high-demand operations, pressure transmitters offer the best reliability and integration flexibility.
