RS485: an intelligent instrument developed with the maturity of single chip microcomputer technology in the early 1980s. The world instrument market is basically monopolized by intelligent instruments, which is attributed to the demand of enterprise informatization, and one of the necessary conditions for enterprise instrument selection is to have a networked communication interface. At first, it was a simple process of data analog signal output. Later, the instrument interface was RS232 interface, which could realize point-to-point communication, but could not realize networking function. RS485 later solved this problem.
NB-IoT: The meter reading scheme does not need wiring, and it is suitable for the application environment with scattered owners, long distance and high requirements for real-time data. The difficulty of networking is low, and concentrators and collectors are not needed. The water meter is directly and automatically connected with the telecom base station, which has a wide coverage and more convenient communication, and is not limited by the installation distance of the water meter. As long as the installation position of the electric meter can communicate with the base station, remote meter reading can be realized.
LoRa: Remote meter reading scheme for water meters: It is suitable for scattered and far-away environments that require high real-time data, such as factories, villas and shopping centers. , the remote meter reading distance can reach 4. 1 m, without additional wiring. As long as a project ensures that the concentrator has GPRS model, the data can be transmitted to the server five floors away. The water meter is powered by the internal battery, and communication can be realized without power cord and intelligent debugging module.