Pump VFD or VSD for Constant Pressure Water Supply System Solution

VFD pump is also called as pump variable frequency controller. In recent years, the pump VFD is widely used in constant pressure water supply system, fire fighting apparatus, tall building water supply system, water treatment equipment, environment engineering and more areas.

1. Disadvantages of Traditional Water Supply System

The traditional water supply system is composed of water tower, high water tank or pressure tank pressurization equipment.

a. Comparing with the modern VSD pump water supply system, the tradition method has a high equipment investment cost. 

b. It has a large pump shaft power and energy loss in the use of these traditional water supply systems.

c. It is likely to cause secondary pollution of water.

By using Veichi VFD water pump AC70, AC80 and more models), you can quickly create an efficient yet economic constant pressure water supply system with obvious energy-saving effect.

2. Benefits of Using Veichi Pumps VFD drives

a. Energy efficient: pump VSD can help you save 20%-40% electricity which is eco-friendly.

b. It is of small accounting area, less investment and high working efficiency.

c. It has high configuration flexibility, high degree of automation, rich functions and stable performance.

d. Reasonable running, with soft starting and soft stopping, can eliminate water hammer effect. Therefore, the average motor shaft torque and wear will be reduced a lot. Not only reduces the maintenance cost, but it also greatly improves the life span of pump and the whole water supply system.

e. The constant pressure water supply system directly gets water from the source water, so it reduces the secondary pollution which is effective to prevent much infectious disease transmission.

f. Communication control: pump VFDs can help you achieve unattended control, saving manpower.

3. Energy Conversation Principle of Pump VFDs

The pump flow and pump (3 phase asynchronous motor) speed is proportional, the pump head is proportional to the square of pump speed, the pump shaft power is equal to the product of flow and head, so the water pump shaft power is proportional to the three cubed pump speed. From these formulas, we can get to know that changing the pump speed is to changing the pump power.

The follow basic formula is:

In the above formula, Q stands for flow, N stands for pump speed, H stands for head, and KW stands for the shaft power.

For example: if we change the supply frequency from 50Hz to 45Hz, so P45 / P50 = (45/50) 3 = 0.729, P45 = 0.729 P50. If we change the supply frequency from 50Hz to 40Hz, so P40 / P50 = (40/50) 3 = 0.512, P40 = 0.512 P50.

The pump water supply system is designed according to the maximum needs in practical conditions, but the actual use of water supply system do not necessarily reaches the maximum amount of water, so the valve regulating system increases the resistance to the throttle. In case like this, it will cause a lot of loss of electrical power. The use of pump VSDs allows the system to work smoothly and stably by changing the pump speed to regulate the water supply, so that is the reason why constant pressure water supply system is of high energy efficiency and low cost.

4. Common Applications of Veichi VFD for Pumps

a. Domestic water supply system in high-rise buildings, urban and rural residential areas, enterprises and so forth.

b. It is also commonly used in various industrial constant water control needs such as cooling water, heating network water cycle, boiler feed water and so on.

c. You can also find the great use of Veichi pumps VFD in the pressurization system in water plants.

d. It is also applied in irrigation, sewage treatment and artificial fountains.

e. Other fluid constant pressure control systems.

If you are interested in Veichi VSD or VFD for pumps or want to learn the parameter settings and wiring diagram, please contact us and our technical support will reply you as soon as possible. If you plan to make use of solar energy to drive water pumps, please take a look at our solar water pumping inverter.