Prepaid water meter is suitable for the urban tap water metering and billing, avoids stealing events of the water, water, running water, through the electronic billing achieved the purpose of water saving and scientific management and changed the traditional way of urban water supply management, change "of" water before you pay for "pay first, after the water", improve the modern management level of the water supply industry, At the same time, it is convenient for users to use, and avoids the inconvenience caused by the charge for table lookup.