Abstract : This paper introduces a constant voltage water pump system controlled by an inverter. The system configuration diagram and electrical wiring diagram are presented, and an example is provided. Keywords : Inverter , Constant voltage, water supply 1 Introduction Using a variable frequency drive (VFD) to achieve constant pressure control in a water supply system is a familiar concept. Achieving constant pressure control in a water supply system not only improves water quality and meets the increasing demands for a higher quality of life, but also provides crucial protection for the safe operation of the entire system. It effectively reduces leaks and drips in the water supply pipeline, thereby significantly lowering the operation and maintenance costs of the pipeline network. Traditional water supply systems mainly provide users with a relatively stable water pressure source through elevated water tanks, water towers, and other water supply facilities. Elevated water tanks and water towers are supplied with water by pumps according to specified upper and lower water levels (or a constant water level system using a frequency converter). Although water towers and tanks are relatively simple, they both pose pollution problems. Therefore, recently, people have gradually started using frequency converter-controlled constant pressure water supply pump systems to replace traditional water towers and tanks to solve the problems of high cost and pollution. [b][align=center]For details, please click: Application of VLT2800 Series Variable Frequency Drives in Constant Pressure Water Supply[/align][/b]