Introduction Intelligent water meters are high-tech products that have been developed in recent years based on automatic control technology and information network technology, relying on information management requirements, to establish information service and communication channels between water departments and users at both urban and rural levels. Widely used, it plays an important role in the communication and service between managers and users. It is a platform for interactive communication between the two.

1 Application status of smart water meters 1.1 Classification of smart water meters Based on the information and networking applications of smart water meters, it is not a concept of water meters in the traditional sense. Instead, it is based on the concept of 'system' and 'integration'. And develop smart water meters. In order to have a more comprehensive understanding of the development of smart water meters, first of all, an overview of the current status of application of long-range smart card readers and smart meters, to explore possible problems in the current way, to provide a coordinate for the future development direction of smart water meters. Or starting point.

At present, according to the system function and hardware platform constructed by the intelligent water meter, the smart water meter can be divided into a smart meter remote centralized meter reading system (hereinafter referred to as a remote collection copy) and a card type smart meter system.

1.2 The composition of long-distance copying and the status quo of its technical application The long-range copying mainly consists of three parts: the base table, data storage and communication system, and back-end software operating system.

The base table refers to the meter that accurately measures the amount of water and collects the measurement information through the sensor and converts it into an electrical signal. The base meter mainly includes the metering mechanism and the sensor. At present, the main current base meter is to measure the amount of water passed by the impeller in the metering mechanism of the water meter. The flow rate information recorded by the rotation frequency of the impeller is displayed successively through the indicator elements (pointer, character wheel, etc.) of the water meter. The components containing flow information, such as the impeller, pointer, and character wheel, are collectively referred to as measuring components. The sensor collects the movement of the measuring components and converts the measurement information into electrical signals.

According to the order in which the metering elements transfer the energy of the water flow in the base table, the moving element directly moved by the action of the water flow is called a primary metering element, such as an impeller; the movement of the primary metering element is gradually reduced and the metering information can be added. The indicated elements are called secondary metering elements such as hands (or gears connected to them) and character wheels. At present, the commonly used meters for metering are multi-brew water meters, mainly rotor-type water meters and horizontal-wing type large-diameter water meters.

At present, commonly used sensors are mainly divided into magnetic sensors, inductive sensors and direct reading sensors.

Magnetic sensors include reed switches, Hall elements, Wiegand, etc. Since the reed switch and Hall elements are affected by the service life and operating frequency respectively, they mainly collect the secondary measuring elements and switch them separately. And pulse output signal. The Wiegand can be used in all kinds of metering components without being affected by the life and operating frequency, and outputs signals in the form of pulses.

In the application, the magnetic sensor has great influence on the sensitivity of the water meter and the external magnetic interference, and also has an adverse effect on the service life of the water meter. Therefore, the magnetic sensor has certain limitations in use. However, due to its low price, simple installation, and suitable for mass production, magnetic sensors are still widely used today.

The inductive sensor mainly obtains the measurement information by collecting the periodical attenuation of the oscillating signal, and is mainly applied to the primary metering component. Due to the non-magnetic excitation, the impeller has small motion damping and is resistant to external magnetic interference, and is suitable for various applications. Water quality, with a wider range of applications. At present, due to the limitation of the manufacturing process of the inductor coil, the iron core in the coil is disturbed to a certain extent by the external magnetic, so the anti-magnetic resistance needs to be further improved. At present, with the improvement of coil manufacturing technology and related technology, all-magnetic inductors have been developed and applied.

Direct-reading sensors can be classified into two types: photoelectric and mechanical. The photoelectric type can be divided into reflective type and indirect type according to the relative positions of the transmitter and the receiver. Photoelectric direct reading is the collection of relevant information on the secondary measuring elements of the character wheel, thereby determining the character wheel readings. Photoelectric direct reading Because of the application of sensor elements, the complexity of the hardware circuit, and the high process requirements, the cost is high, and the mass production process is difficult. The mechanical direct reading is mainly through the direct contact of the compression reed to the code wheel to obtain the coding information so as to determine its corresponding indication position. Although this method is lower in cost than the former, it suffers from problems such as poor reliability, large mechanical damping (large initial flow of water meter), and mass production process needs to be improved due to the influence of the reed material and processing technology.

In summary, at this stage, the smart meter's base meter shows a diversity of features in the metering and sensing technologies. Due to the limitations of the current technology level and process technology, various methods have not formed outstanding technical advantages. Industrial advantages.

In terms of data communication, the current communication method using RS485 bus and MBUS bus has a relatively perfect standard system. At the same time, the communication technology of smart water meter is developed along with the development of modern communication technology. At present, the data communication is in addition to the wired method. Various wireless meter reading technologies are also emerging. In the back-end software operating system, the existing software has different characteristics in terms of service modes, charging methods, and data interfaces. Therefore, the background software system has the characteristics of being personalized and mutually incompatible. In the application of long-distance copying, the system administrator mainly unilaterally obtains relevant data from the user side, such as water consumption. This unidirectionality of data exchange causes the asymmetry of the information obtained by both parties.

Although there are various contradictions in the base list, background processing and other aspects of remote collection, it initially establishes a real-time communication channel between managers and users to achieve socialization, intensive, real-time, and humanity for water management activities. The supporting role played by modern management requirements, such as chemical transformation, is irreplaceable.

1.3 Card Smart Water Meter System and Its Application Status The card type smart meter system is composed of three parts: a card smart water meter, a read-write card, and a background processing system.

The smart card water meter is a kind of water meter with prepayment function, which is composed of a water meter with a sending device as a metering base, a card reading and writing as media, and a controller and an electric control valve. A read-write card refers to a medium that can perform reading and writing operations, such as an IC card, a TM card, a radio frequency card, and the like. The background processing system refers to the hardware and software system that can read and write the card. In this system, since the reader-writer card bears the communication between the manager and the user and the communication between the user and the card table, and the user is the holder of the reader-writer card, it is subject to a certain degree of real-time communication between the manager and the user. Constraints, this non-real-time, while reducing the degree of humane service between managers and users.

2 The development direction of smart water meters is based on the status of hardware configuration and networked services of smart water meter systems.

The development directions of smart water meters are: economical and practical, two-way real-time, and data sharing.

Smart metering is an inevitable need and product of the development of the information society. It will eventually become a "civilian" product for millions of households. Therefore, economy and practicality are the inevitable choices for smart metering in the market. This article mainly discusses the economy and practicality of smart water meters from the base table.

Traditional water meters are still the first choice for smart meter base meters in the future. Single-bundle water meters are simple in structure and small in size. They have the highest price/performance ratio in all water meters of the same specification, and their quality is much higher than that of other specifications. The quality of the water meter of the type is reduced by 20% to 40%. Due to the improvement of the level of processing technology and design, the batch qualification rate can reach about 90%, the production cost can be significantly reduced, and the reliability and lifespan of the product can be greatly exceeded in the past. Because the sensor installation method of the primary metering component is simple and the acquisition accuracy is high, the production cost is low, and the process performance is good. At the same time, it can be used as a base meter for developing a high metering accuracy class. Non-magnetic sensor is the direction of sensor technology development, its quality should reach: from the meter's initial flow to the flow of the overload flow collection of full response; low power consumption; anti-interference; no damping and apply to a variety of water quality. At present, inductive coil sensors have achieved initial results in development and application. Therefore, the single-bundle all-magnetic (inductor coil) base meter has a high measurement accuracy level (D-level accuracy), high sensitivity (3 to 4 L/h), strong anti-interference ability (interference of external magnetic field), use Long life, high cost performance and many other advantages, can better reflect the economic and practical requirements of smart meter base table.

In the long run, with the improvement of sensor technology and industrial application, various high-grade flowmeter technologies, such as ultrasonic flowmeters and electromagnetic flowmeters, will be widely used in the design and use of water meters. The base table has a simple structure, realizing the advantages of no mechanical transmission, long life (equivalent to component life or pipeline life), no pressure loss, wide range of accurate measurement (equivalent to the flow capacity of the installed pipeline), and the like. At present, the application of this technology in small-diameter (DN152DN40) and large-diameter (DN502DN500) base tables is in the development stage, and its sensors (transducers) are subject to the constraints of process technology, the cost is high, and industrial development and application needs to be relatively A long period of time.

Bidirectional real-time is the requirement for system communication and network technology. Users of smart metering systems are water managers and users. The level of application of the system depends on the degree of two-way interactive communication and the real-time nature of two-way communication. As mentioned above, at this stage, the system of collecting and copying unilaterally establishes channels for managers to obtain information from users in real time. For example, managers can obtain information about user water consumption through the system, and users cannot obtain management in real time through the system. The service information of the person, this asymmetry of obtaining information restricts the effectiveness of interaction between the two parties. Although the smart card meter system can achieve two-way communication between the manager and the user through reading and writing the IC card, the manager can understand the user's consumption behavior and other related information through the card reader and the background processing software, and the user can also Through the reading and writing of the card and the display interface in the base table to understand the manager's management and service behavior and other related information, but the lack of real-time communication between the two sides, easily lead to management and service behavior lags behind. It can be seen that the network has realized the real-time communication between the two parties; the application of the read-write card has realized the mutual exchange of information between the two parties, and the application of the control valve has enriched the remote control and execution functions. Therefore, the establishment of a smart water meter system consisting of a card smart water meter, a read-write card, a remote data collection network, and corresponding back-end data processing software can deepen the mutual communication behavior and increase the breadth and depth of smart meter applications.

Sharing is the need for system socialization. With the increasing level of man's intensive management of water resources, human data on water use is not only a local, regional concern, but more and more becoming a The country, a social concern. Therefore, the sharing of data has become the basis for the entire society to achieve intensive management of water resources. For a long time, the background data processing software has various forms such as data interface, management flow, etc., resulting in low level of data exchange and sharing. Therefore, the standardization and modularization of background data processing software is the only way to achieve data sharing. Standardization ensures the unification of data reading methods, and modularization can ensure the diversified demand for software functions of water management, improve the applicability of software applications, and realize the cross-regional integration of water management.

3 Conclusion The intelligent water meter system continues to advance with the development of modern metrology technology, sensor technology and information network technology as well as socialization needs. The economical and practical, two-way real-time, and data embodied in the future development of smart water meter system The characteristics of sharing are the embodiment of this kind of technological development and the development of social needs. At the same time, it also reflects the concept of the coexistence of human beings and water resources.