Introduction:
In order to fully meet people’s growing material needs, smart water meters have gradually replaced non-smart water meters. In the application process of smart water meters, the RS485 bus is widely used. The bus structure is simple to apply and the cost is low, so it has been widely used. application, but to ensure the reliability of its application, extend the service life of smart instruments, and effectively reduce the probability of data errors, it is necessary to ensure that the RS485 bus does not make mistakes in the design process and is scientific and reasonable.
In recent years, the increase in various residential areas has also led to the continuous increase and concentration of the use of water meters. This large number of water meters has also greatly increased the workload and work pressure of meter readers. The traditional work of meter readers This method is not only difficult to improve work efficiency, but also brings certain troubles to residents, and it is difficult to ensure the accuracy of data through manual meter reading. In order to effectively solve the above problems, it is imperative to apply intelligent meter reading systems.
1. Current status of RS485 bus in intelligent meter reading systems
The RS485 bus is mainly suitable for communication systems with communication distances from tens of meters to several kilometers, and it mainly works in the form of balanced transmission and differential reception. In addition, the RS485 bus has strong suppression of common mode interference. The capabilities and transceivers used basically have high sensitivity, which can enable the transmission signal to be recovered thousands of meters away. In addition to strong interference suppression capabilities and high sensitivity, the RS485 bus also has simple usage, simple distribution, It has the advantages of high stability, so it is also widely used in intelligent meter reading systems [1]. 2. Application of RS485 bus in intelligent meter reading system.
2. Application of RS485 bus in intelligent meter reading system
1) RS485 bus theory RS485 bus theory includes grounding method, wiring, wiring, etc. If the RS485 bus wants to maximize its effect, single-point grounding is the best wiring method, and this is also to ensure the voltage on the ground line Consistent voltage can also effectively prevent common mode interference [2]. During the RS485 bus wiring operation, relevant personnel should pay attention to the fact that the RS485 bus cannot be routed together with the high-voltage power line. However, judging from the actual construction situation, a considerable number of construction workers have connected the RS485 bus and the power line in order to reduce the workload. After bundling, complete the wiring work together, but in this case, the electromagnetic signals contained in strong electricity will affect the stability of the RS485 bus. Finally, the RS485 bus has no fixed wiring form. Whether it is star wiring or tree wiring, the final layout effect can be obtained. However, industry principles must be strictly followed during the wiring process, and the role of RS485 hubs and RS485 repeaters must be fully utilized to avoid signal instability.
2) Factors affecting the reliability of RS485 bus communication 1. Wiring method. In the process of RS485 bus, changes in cable wiring methods and extension of transmission distance will cause cable impedance discontinuity or mismatch, which will cause echo reflection signals to appear in the line, disrupt signal transmission, and cause communication failure or failure. error alarm. To effectively avoid echo reflection, a terminal resistor must be connected across the end of the cable to ensure the continuity of the cable impedance. 2. Signal attenuation. Signal attenuation is also a common phenomenon during cable transmission. For the same standard cable, the communication baud rate affects the line attenuation coefficient. Therefore, in the process of selecting cables, attention should be paid to whether the selected cables meet the design specifications and can adapt to the transmission baud rate, so as to minimize the impact of signal attenuation. 3. Node load. The number of node loads in the RS485 bus segment is inversely proportional to the transmission distance when the load capacity of the bus and the communication baud rate are certain. Therefore, in order to ensure the quality of the bus, during the construction process, it should be ensured that the node position of the bus device is within the bus signal Within the transmission distance, the bus equipment can be guaranteed to operate normally.
3. The significance of the RS485 bus in the application of intelligent meter reading systems
In recent years, my country’s power system is developing in the direction of intelligence. Traditional energy meters have been gradually replaced by smart energy meters using the RS485 bus. This also means that smart energy meters using the RS485 bus are constantly promoting the process of intelligentization of the power system. . Therefore, enterprises should follow the development trend of the information age and deeply integrate modern information technology with enterprise development. In particular, they should pay attention to the construction of intelligent meter reading systems, improve the intelligence of the meter reading accounting and charging system, and pay attention to the RS485 bus in intelligent meter reading. applications in the system. Conclusion: Applying the RS485 bus to the intelligent meter reading system can not only greatly reduce the workload of staff, but also effectively improve work efficiency and quality. The deep integration of intelligent technology with power meter reading can not only effectively improve the efficiency of meter reading. The skill level of the process can effectively improve work efficiency and ensure the accuracy and reliability of data.
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