In the smart grid system, a very important part is remote meter reading. Early electricity meter reading was to directly read the meter reading at the user's site. In today's increasingly demanding power supply, this method has high cost and poor real-time performance. To this end, there needs to be an efficient, real-time way to achieve remote automatic reading of meter data. GPRS network has the characteristics of good mobility, wide coverage and low communication cost, and is an ideal remote meter reading solution.
Modern building construction has put many electric meters together. These electric meters have built-in single-chip microcomputers, which can read the actual power consumption data through the single-chip microcomputer, and can communicate with the outside through RS-485 communication. Utilize the RS-485 communication capability of the Global DTU to connect it in parallel with the meter, and realize the connection with the mobile network and the meter reading data service center through the DTU, so that the meter reading data service center can directly access each meter , Realized a remote meter reading system.
The remote meter reading system consists of three parts: meter terminal, DTU, and meter reading service center.
1) Electric meter terminal: It mainly completes the recording of user's electricity consumption and responds to external reading instructions.
2) DTU: establish a data communication link and forward data in the meter and meter reading data service center.
3) Meter reading service center: read the value of the meter through communication with DTU.
Mode of operation
1) Always online mode: suitable for occasions where the frequency of meter reading is high. After the DTU is powered on, it automatically connects the mobile network and the meter reading data service center, and maintains the link between the meter and the meter reading data service center. Meter reading can be performed at any time;
2) Trigger on-line mode: It is suitable for occasions with low meter reading frequency, which can save transmission cost. In practice, when the meter has data to upload, or when the meter reading data service center requests meter reading via SMS, the DTU starts to connect the mobile network and the meter reading data service center to complete the data transmission between the two. Automatically restore the standby state;
typical application
The remote meter reading solution solves the problem of difficult distribution of distribution points. It is one of DTU's mature application solutions and can be widely used in power meter reading, water meter reading, natural gas meter reading, pipeline meter reading, and so on.