Reverse osmosis system is generally used for food water purification equipment, which is mainly used in beverage, wine making, dairy products, fermentation, food processing and other industries. Pretreatment or purified water is usually required for water quality requirements, and the conductivity is usually below 10us / cm. On the basis of meeting the user's water use standard, Hongjie water science and technology has set liquid level control system in the water tank, pressure protection device in the water pump, on-line water quality detection and control instrument, and PLC programmable controller in the electrical system, so that no one is on duty. At the same time, the unified method of recommendation and customer requirements is adopted in the process material selection, Compared with other similar products, the equipment has higher cost performance and equipment reliability.