Variable frequency constant pressure water supply equipment

Product Specification

Variable frequency constant pressure water supply equipment | Energy-saving and stable · Fully automatic constant pressure water supply

This equipment employs advanced variable frequency speed control technology, using pressure sensors to monitor pipeline pressure in real time and automatically adjust the pump speed and number of pumps in operation to maintain the outlet water pressure within the set range. Regardless of changes in water consumption, the water pressure at the user end remains constant. The system integrates a variable frequency control cabinet, pump unit, pressure sensor, pressure tank, and pipeline accessories. Compared to traditional fixed frequency water supply, it can save 30% to 60% of electricity while avoiding water hammer and extending equipment life. It is widely used in high-rise buildings, residential communities, factories, hotels, farmland irrigation, and the renovation of old pump stations.

core components

Variable Frequency Control Cabinet: PLC or dedicated water supply controller + frequency converter, PID closed-loop regulation, supports multi-pump rotation and fault redundancy.

Pump Units: Vertical multistage centrifugal pumps or stainless steel horizontal pumps (2-6 units), flow rate and head can be combined as needed, low noise, high efficiency.

Pressure Sensors: Remote pressure gauges or 4-20mA pressure transmitters, providing real-time feedback of pipeline pressure.

Pressure Tanks: Diaphragm or bladder-type pressure stabilizing tanks, used for low-flow pressure maintenance and preventing water hammer, reducing frequent pump start-stop cycles.

Pipelines and Valves: Stainless steel or galvanized steel pipes, equipped with check valves, butterfly valves, flexible joints, and inlet/outlet assemblies.

Optional Accessories: Level controller (water tank water shortage protection), remote monitoring module, flow meter, disinfection device.

Working principle

A pressure sensor is installed at the outlet of the water supply network, transmitting pressure signals to the frequency converter in real time. The controller compares the measured pressure with the user-set pressure, performs PID calculations, and outputs a frequency command to the frequency converter to adjust the water pump speed. When water consumption increases, causing a drop in pressure, the water pump accelerates; when water consumption decreases, the water pump decelerates; when water consumption is extremely low, the water pump enters sleep mode and the pressure is maintained by a pressure tank; when multiple pumps are used, the number of operating pumps can be automatically increased or decreased. The entire process is fully automatic and requires no manual intervention.

Main advantages

Constant Pressure Comfort: The water pressure remains constant, eliminating fluctuations at the user end, ensuring stable operation for showers, washing machines, etc.

Significant Energy Savings: Variable frequency soft start eliminates inrush current; automatic speed adjustment based on water demand results in average energy savings of 30%–60%.

Pipeline Safety: Eliminates water hammer from direct start-up, reducing the risk of pipe bursts and pump damage.

Automatic Pump Rotation: Multiple pumps can rotate on a timed basis, balancing wear and extending the overall lifespan of the unit.

Fault Protection: Equipped with overload, phase loss, dry running, and overpressure protection functions, and automatically activates the backup pump.

Easy Installation: Integrated skid-mounted design; simple inlet and outlet flange connection; compact footprint.

Optional Remote Monitoring: Monitor pressure, frequency, and fault status via mobile app or host computer.

Technical parameters

Flow rate range: 2 – 500 m³/h (customizable)

Head range: 20 – 250 m

Number of pumps: 1–6 units (commonly 2 in operation, 1 on standby or 3 in operation, 1 on standby)

Control method: Constant pressure variable frequency (PID)

Pressure control accuracy: ±0.01 MPa

Power supply: Customizable

Pressure tank capacity: 8L – 500L (diaphragm type)

Pipeline material: 304 stainless steel / galvanized steel

Installation method: Vertical or horizontal skid-mounted

Application areas

Secondary water supply for high-rise residential buildings, villas, hotels, and schools; factory production water and flushing systems; agricultural greenhouse irrigation and sprinkler systems; hot water system makeup and boiler pressure-regulating water makeup; automated energy-saving renovation of existing old pump rooms. We can provide pump selection and control system configuration based on your water flow rate, head, building height, and number of users. Welcome to send parameters to obtain a quotation and solution diagram.