Frequency control devices are a new generation of energy-saving water supply equipments produced by our company. The core of which is AC frequency conversion technology and microcomputer technology. Shan-yu company adopted inverter converter or other well-known brands, intelligent controller, pressure sensor and the companys SLS, SLW, GDL, DL series pumps composed of closed-loop control system. The device can automatically adjust the pump speed and the number of running, so that the pressure of the water supply network  can maintain the setting pressure and  required flow, so as to achieve the purpose of  enhancing water quality and highly efficient energy-saving. The device can be used to replace high water storage tanks, cooling towers and other facilities. It can improve the degree of water supply automation and the quality of drinking water. It can prevent secondary pollution, and is an ideal modernization equipment  of the water supply.