Industrial metering point wireless monitoring system

0 Introduction
    With the rapid growth of China's economy, the demand for energy continues to increase rapidly. China has become the second largest energy consumer in the world. However, China's per capita energy resources are far below the world average. The contradiction between economic development and resources and environment is becoming increasingly acute. Facing the dual pressure of energy security and environmental protection, the strategic position of energy and resource conservation is extremely prominent. Strengthening energy management and improving energy utilization efficiency are the fundamental guarantees for alleviating the energy constraint contradictions faced by current economic and social development, building a conservation-oriented society, and achieving sustainable economic and social development.
    Industrial enterprises are major energy consumers in China, and their energy consumption accounts for 70% of the total energy consumption of the whole society. The high energy consumption problem of enterprises has become a bottleneck restricting the development of industrial economy, and energy conservation and consumption reduction of industrial enterprises has become a basic obstacle to the sustainable development of industrial economy. During the "12th Five-Year Plan" period, the state further carried out the control of total energy consumption, among which the industrial energy conservation target was set at 21%. To achieve this goal, each enterprise must take energy conservation and consumption reduction as a key task, and strengthening energy measurement management is the basis and guarantee for energy conservation and consumption reduction of enterprises.
    Energy metering refers to the detection, measurement and calculation of the quantity, quality, performance parameters and related characteristic parameters of each link in the energy process, so as to achieve the purpose of improving energy utilization efficiency and saving energy. The management of industrial enterprises should firmly grasp the characteristic of "high energy consumption", strengthen internal management, improve the energy metering management system, promote new metering management technologies, and adopt modern means of networking and informatization to achieve energy conservation and consumption reduction and technical improvement.

1 Technical difficulties in establishing an industrial metering system
    The distribution of industrial on-site energy metering monitoring points (water, electricity, wind, gas, etc.) is usually scattered. There are both overhead and underground monitoring points inside and outside the production plant. Some are newly added monitoring points and no signal transmission cables are reserved. If a wired method is used, a large number of cables, network cables and optical fibers need to be laid to form a transmission network, and the equipment construction and maintenance costs are very high. For some harsh environments, wiring and power supply will be restricted, and it is often difficult to monitor data, and it will also bring inconvenience to future maintenance. If the cable is damaged by maintenance or other reasons, it will be extremely difficult to restore.
    GPRS wireless transmission technology can be widely used in environment and equipment monitoring, and it is simple to implement and reliable in communication, but it is not economical because of its high usage fee. Usually, the annual cost of a communication point is thousands of yuan. The more metering points there are, the higher the cost. It is not suitable for large-scale data collection. The
    above factors have restricted the establishment of energy metering management system to varying degrees. Therefore, in order to establish a complete energy metering management system that can be implemented quickly, has reliable communication and reasonable cost, a new technology must be sought.

2 Application of Wireless Sensor Network Technology in Industrial Measurement
    Wireless Sensor Network (WSN) technology is a new low-power, self-organizing, short-distance wireless transmission technology in the world. It integrates sensor technology, embedded computing technology, distributed data processing technology and communication technology. It can monitor, sense and collect data of various environments or monitoring objects in the network distribution area in real time. These data can be sent wirelessly and transmitted to the user terminal in a self-organizing multi-hop network.
    Wireless sensor network is considered to be an IT hot technology that can have a significant impact on human lifestyle in the 21st century after the Internet. In 1999 and 2003, the US "Business Week" and "MIT Technology Review" listed it as one of the 21 most influential technologies and the top 10 new technologies that will change the world in their reports predicting future technological development. Wireless sensor networks were originally proposed by the US military and have important application value in military fields such as battlefield monitoring. In the civilian field, wireless sensor network technology also has broad application prospects, especially in ecological environment monitoring, advanced manufacturing, medical health, emergency response, building safety monitoring, precision agriculture and other fields. The development of WSN technology in China is relatively late, but after several years of efforts, the technology has gone beyond colleges and laboratories. In many fields, WSN technology has shown its advanced nature and has been widely recognized in applications such as environmental monitoring, building intelligence, and smart cities.
    The field data collection method based on wireless sensor network technology has the characteristics of low cost, high scalability, and high reliability. Applying wireless sensor network technology to industrial measurement occasions can effectively solve the problems of high installation and maintenance costs, power supply, and wiring limitations of traditional monitoring systems. It is more suitable for monitoring tasks in industrial occasions such as multi-node, large-scale, and harsh environments. [page]

3 Composition of the wireless monitoring system for metering points
    The wireless monitoring system for industrial metering points is generally composed of wireless sensor network nodes, wireless sensor network relays and gateways. Within the wireless communication range, the sensor node can automatically identify and join the wireless transmission network after being turned on, and regularly send a variety of industrial transmitter standard signals, including resistance signals, current signals, and voltage signals (involving pressure, flow, and temperature measurements) through wireless, self-organizing, and multi-hop methods, and finally converge to the gateway. If the sensor node is far away from the gateway, the sensor node will automatically forward the collected data to the gateway through the relay node. After the gateway collects the data from the sensor node, it will transmit the data to the background through 3G, GPRS, Wi-Fi, Ethernet, serial port, etc. Figure 1 shows a schematic diagram of the wireless monitoring system for metering points.

4 Conclusion
    The wireless monitoring system for industrial metering points uses wireless data transmission, which can automatically form a monitoring network to collect and transmit monitoring data, thereby ensuring the reliability and real-time nature of the monitoring data and saving a lot of manpower and material resources. The main features of this system are as follows:
    (1) Flexible installation organization: Wireless intelligent sensors and wireless relays can be arbitrarily distributed within the effective wireless communication distance, and data transmission is carried out through self-organization to form a network, which is extremely convenient to install;
    (2) The damage of individual wireless relays does not affect the overall function, and its changes and failure information are automatically summarized to the wireless gateway, which is convenient for maintenance;
    (3) Low networking cost: Only wireless intelligent sensors, wireless relays and wireless gateways are needed to build a data transmission network;
    (4) Stable and reliable equipment: Wireless intelligent sensors are completely sealed and can be used in harsh environments;
    (5) The equipment itself is energy-saving and environmentally friendly: Wireless intelligent sensors use low-power technology. When powered by batteries, they can work continuously for 1 to 5 years (depending on the monitoring task) and can achieve maintenance-free during the monitoring process;
    (6) Safe and reliable data transmission: The nodes use frequency hopping technology, which can work reliably in complex electromagnetic environments and have strong anti-interference ability.