Water Supply System(VFD Booster Set)

VFD Constant Pressure Water Supply System

The FILIPUSI constant pressure water supply system is a factory-assembled, skid-mounted variable frequency booster set that delivers stable water pressure regardless of fluctuating demand. Each system combines one to six vertical multistage centrifugal pumps with a VFD control panel, PLC/PID constant-pressure controller, pressure transmitter, manifold piping, isolation and check valves, and a diaphragm pressure tank — pre-wired, pre-piped, and fully tested before delivery for fast on-site installation.

A pressure transmitter continuously monitors discharge pressure and feeds the signal to the PID controller, which adjusts pump speed in real time to hold the set pressure within ±0.01–0.05 MPa. In multi-pump sets, pumps cascade on and off according to demand and alternate duty to ensure even wear. Compared with fixed-speed and conventional hydro-pneumatic systems, FILIPUSI VFD booster sets reduce energy consumption by 30–60% while eliminating pressure fluctuation and water hammer.

How the Constant Pressure System Works

1	Pressure sensing: A pressure transmitter on the discharge header measures network pressure and sends a 4–20 mA / 0–10 V signal to the controller.
2	PID closed-loop control: The PLC compares actual pressure with the set point and commands the VFD to speed up or slow down the lead pump, holding constant pressure at every flow.
3	Multi-pump cascade: When the lead pump reaches full speed, lag pumps stage on automatically; as demand falls they stage off. Duty rotation equalizes running hours across all pumps.
4	Sleep & wake: At zero demand the system ramps down and sleeps, with the diaphragm tank maintaining pressure; it restarts instantly when a tap or valve opens — preventing short-cycling.

System Components

Component	Specification
Booster Pumps	1–6 vertical multistage centrifugal pumps (simplex / duplex / triplex / quadruplex), AISI 304 standard, 316/316L optional
Control Panel	VFD (variable frequency drive) + PLC/PID constant-pressure controller with HMI display, housed in IP54/IP55 steel cabinet
Pressure Transmitter	High-accuracy 4–20 mA pressure sensor, control accuracy ±0.01–0.05 MPa
Diaphragm Tank	Bladder-type pressure tank sized to the system; absorbs water hammer and prevents short-cycling
Manifold & Valves	Stainless steel suction/discharge headers, full-port isolation valves, check valves, pressure gauge, drain
Base Frame	Fabricated steel skid / base frame, anti-vibration mounts, factory-aligned and pre-tested
Protection	Dry-run / low-water, overload, over/under-voltage, short-circuit, and phase-loss protection as standard
Communication (optional)	Modbus RTU, BMS/BACnet integration, remote monitoring and alarm output

Technical Specifications

Parameter	Range / Specification
Pump Configuration	Simplex (1), Duplex (2), Triplex (3), Quadruplex (4); up to 6 pumps on request
Total Flow Rate	Up to 800 m³/h (custom-engineered)
Discharge Pressure / Head	2–25 bar / heads up to 250 m
Motor Power per Pump	0.37 kW – 200 kW
Pressure Control Accuracy	±0.01–0.05 MPa
Voltage / Frequency	380V/50Hz 3-phase standard; 220V/415V/440V/460V, 50/60Hz on request
Motor Efficiency / Protection	IE3/IE4/IE5 premium efficiency, IP55, Class F
Fluid Temperature	0–70°C standard; hot-water type up to 120°C
Wetted Materials	AISI 304 stainless steel (standard), AISI 316/316L (optional)
Control Cabinet	IP54/IP55, indoor (outdoor/weatherproof on request)
Certifications	100% factory function & pressure tested | Pre-wired & pre-piped

Core Advantages

Constant, Stable Pressure PID closed-loop control holds pressure within ±0.01–0.05 MPa across all taps and floors — no fluctuation during peak demand.

30–60% Energy Saving Variable speed matches output to real demand, eliminating throttling losses and full-speed running — typical payback within 1–2 years.

Plug-and-Play Skid Factory pre-piped, pre-wired and tested on a single base frame — connect inlet, outlet and power to commission, cutting installation time.

Redundancy & Reliability Multi-pump duty/standby configuration with automatic alternation ensures continuous supply even if one pump is serviced.

No Water Hammer Soft start/stop and the diaphragm tank absorb hydraulic shock, extending the service life of pumps, pipes, valves and seals.

Smart & Protected Dry-run, low-water, overload and phase-loss protection; optional Modbus/BMS remote monitoring for unmanned plant rooms.

Typical Applications

High-Rise & Commercial Buildings Residential towers, hotels, hospitals, schools, office complexes and shopping malls requiring even pressure on every floor.	Municipal & Secondary Water Supply Booster stations for municipal networks, residential communities, and secondary (roof-tank bypass) water supply projects.
Industrial Process Water Manufacturing plants, food & beverage, pharmaceuticals, electronics and general factory water supply and circulation.	Water Treatment & RO Feed and product-water boosting for water treatment plants, reverse osmosis systems, and ultrafiltration/purification lines.
HVAC Make-Up Water Chilled and hot water system make-up and pressure maintenance for commercial and district energy systems.	Irrigation & Agriculture Large-scale irrigation, greenhouse and landscape watering where stable pressure and low operating cost are required.

VFD Booster System Applications & Sizing

VFD Booster System Sizing for High-Rise Residential & Commercial Buildings

Sizing a VFD constant pressure booster system for high-rise buildings requires careful calculation of both peak demand flow and total dynamic head. The peak flow is determined by the number of fixtures (toilets, sinks, showers, hose bibs) and their simultaneous use factor, typically calculated using Hunter's curve or local plumbing code fixture unit values. The total dynamic head includes static elevation (height from pump discharge to the highest fixture), friction loss in piping and fittings at peak flow, and the required residual pressure at the highest fixture (typically 1.5-3 bar). For buildings above 50 meters, a mid-level pressure zone with a secondary booster set may be required to avoid excessive pressure at lower floors. FILIPUSI engineers provide free system sizing including pump selection, pressure zone design, and energy consumption analysis within 24 hours.

Constant Pressure Water Supply System for Municipal Water Distribution Networks

Municipal water distribution networks often suffer from pressure fluctuations due to varying demand throughout the day, leakage in aging pipelines, and elevation differences in hilly terrain. A VFD constant pressure booster system installed at strategic points in the distribution network maintains stable pressure regardless of demand fluctuations, reducing water hammer, minimizing pipe burst incidents, and improving customer satisfaction. The PLC/PID controller continuously monitors discharge pressure and adjusts pump speed in real time, while multi-pump cascade control ensures efficient operation across the full demand range — from low nighttime flow to peak morning and evening demand. Remote monitoring via Modbus or GSM allows municipal operators to track system performance, receive alarm notifications, and adjust setpoints remotely. The skid-mounted, pre-wired, and pre-piped design enables fast on-site installation with minimal disruption to water supply service.

VFD Booster Set Energy Savings: Variable Speed vs. Fixed Speed Comparison

One of the most significant advantages of a VFD constant pressure booster system over conventional fixed-speed and hydro-pneumatic systems is substantial energy savings. Fixed-speed pumps operate at full speed regardless of actual demand, wasting energy through pressure relief valves or throttling valves when demand is low. In contrast, a VFD system adjusts pump speed to match actual flow demand, and since pump power consumption follows the affinity laws (power ∝ speed³), reducing speed by just 20% reduces power consumption by approximately 50%. In typical water supply applications where average demand is only 30-50% of peak demand, VFD booster sets reduce energy consumption by 30-60% compared to fixed-speed systems. The payback period for the additional VFD investment is typically 1-3 years depending on electricity costs and operating hours. Additional benefits include reduced water hammer, extended pump and seal service life due to soft starting, and precise pressure control that eliminates the pressure fluctuations common with hydro-pneumatic systems.

Packaged Booster Pump System with PLC Control & Remote Monitoring

FILIPUSI VFD water supply systems are delivered as fully packaged, skid-mounted booster sets that include one to six vertical multistage centrifugal pumps, a VFD control panel with PLC/PID constant-pressure controller, pressure transmitter, manifold piping with isolation and check valves, a diaphragm pressure tank, and all necessary instrumentation — pre-wired, pre-piped, and fully tested before delivery. The PLC controller provides comprehensive functionality including multi-pump cascade control, pump duty alternation for even wear, dry-run protection, high/low pressure alarms, and fault diagnostics. Standard Modbus RTU/TCP protocol support enables integration into building management systems (BMS), SCADA systems, and industrial automation networks. Optional GSM remote monitoring allows operators to receive SMS alarm notifications and access real-time system performance data from anywhere with cellular coverage. The compact skid design minimizes on-site installation time and requires only connection to suction and discharge piping, power supply, and communication cable.

How to Select Your Booster System

01	Design flow & number of users: Provide peak hourly flow (m³/h), number of floors/fixtures, and simultaneous-use factor. We size total pump capacity and the number of duty/standby pumps.
02	Required set pressure: Specify target discharge pressure (bar) and building height / static head, plus available inlet (suction) pressure.
03	Configuration & redundancy: Choose simplex for low-demand duty; duplex/triplex for continuous or critical supply where standby capacity is required.
04	Power, voltage & control: Confirm voltage/frequency, cabinet IP rating, and whether Modbus/BMS remote monitoring is needed.

Frequently Asked Questions

Related Pump Series

VS Vertical Multistage Pumps The core pump used in our booster sets; flows to 270 m³/h, heads to 350 m, all stainless steel. View VS Series »

Inline Booster Pump Compact vertical multistage inline pumps for single-pump pressure boosting. View Inline Booster »

Horizontal Multistage Pumps Ring-section multistage pumps for high-head boiler feed and RO duties. View Horizontal Series »