The development of water meters can be divided into three stages:
The first stage is the period of traditional mechanical water meters. This type of water meter realizes the cumulative display of water flow through a simple mechanical device, which has obvious shortcomings such as low measurement accuracy, poor anti-interference ability, and short service life, and cannot meet the needs of information management.
The second stage is the transitional period for the coexistence of intelligent mechanical water meters and traditional mechanical water meters. Since 2003, with the development of sensors, communication, and radio frequency technology, intelligent mechanical water meters have been born, realizing functions such as data collection and transmission, prepaid water use, and network valve control. However, its core metering method still uses mechanical devices, and its performance is comparable to that of traditional mechanical water meters.
The third stage began in 2013 when mainstream manufacturers began to use electronic sensing technology to produce electronic water meters. Compared with mechanical water meters, electronic water meters have the advantages of high precision, no wear, small pressure loss, and low power consumption. At the same time, they can realize functions such as real-time flow monitoring, pipe network detection, and data analysis. At present, the most successful commercial applications are ultrasonic water meters and electromagnetic water meters.
Smart water meters can be divided into mechanical water meters with electronic devices and electronic water meters:
The mechanical water meter with electronic device is equipped with an electronic device on the mechanical water meter, which converts mechanical signals into electrical signals, and can realize functions such as remote communication, prepayment, and valve control.
Electronic water meters use electromagnetic, ultrasonic, or jet flow principles for measurement, and have the characteristics of high precision, wide range, long life, and small pressure loss. Ultrasonic water meters are currently the most widely used. Electromagnetic water meters are used in urban water supply and water conservancy projects. They have the advantages of full digital processing, high measurement accuracy, and strong anti-interference, and realize the functions of two-way flow measurement and wireless data transmission.
Common smart water meter products mainly include electronic remote water meters, electronic remote valve-controlled water meters, prepaid water meters, ultrasonic water meters, and electromagnetic water meters.
At present, there are three commonly used methods for a remote meter reading of smart water meters: NB-IoT, LoRa, and GPRS. NB-IoT uses a cellular network and has wide coverage, but it started late. LoRa uses unlicensed frequency bands, is simple and easy to develop, and has a long battery life, but manual meter reading is required to collect data. GPRS technology is mature and the transmission speed is high, but the user capacity and battery life are worse than NB-IoT.
For water supply enterprises, while inheriting the functions of GPRS water meters, NB-IoT water meters have larger user capacity, longer battery life, and stronger signal coverage, which is a better remote meter reading solution.