Magnetostrictive level sensor is composed of three parts: probe rod, circuit unit and float. To measure, the circuit unit generates pulses of current that travel down the magnetostrictive line and generate a circular magnetic field. A float is arranged outside the probe rod, and the float moves up and down along the probe rod with the change of liquid level. The float generates a magnetic field at the same time because it is fitted with a set of permanent magnets. When the current magnetic field meets the float magnetic field, it produces a "twisting" or "return" pulse. The time difference between the "return" pulse and the current pulse is converted into pulse signals to calculate the actual position of the float and measure the liquid level. Magnetostrictive Level Sensor,Magnetostrictive Level Transmitters,Magnetic Type Level Gauge,Liquid Level Sensor,Magnetostrictive Level transmitter Xi'an Gavin Electronic Technology Co., Ltd , https://www.gamicos-meas.com
In the past two years, the market share of China's chain operations has gradually increased. The number of large, medium, and small supermarkets nationwide has reached more than 50,000. There are also thousands of large-scale supermarkets with a business area of ​​more than 5,000 square meters. According to experts According to statistics, the average annual growth rate of supermarkets and chain stores in China is as high as 20%. Its field of development has also extended to industries such as commerce, materials, grain, oil, medicine, tobacco, and services. With the characteristics of flexibility, convenience, practicality, and so on, supermarket chains and shops have gradually become the mainstream of popular shopping in today’s society. The arbitrariness, flexibility, convenience, and practicality of shopping provide citizen's convenience. In the chain stores, people can freely choose their favorite items in the store, to avoid the desire of the sales staff to buy or sell the customers, and not to worry about the low purchasing power of the customers. This flexible shopping method has greatly improved the convenience of shopping and reduced the workload of staff. At the same time, however, it has hidden a certain degree of security risks, such as theft of goods and property, the availability of shelves, or multi-network outlets. Synchronous regulation and so on.
Therefore, while the rapid development of the chain industry, many management issues, including security, have become increasingly prominent. The larger the scale of chain operations and the greater number of chain outlets, the more difficult the security prevention and business management problems are.
Second, demand analysis
For supermarkets and shop managers, the first is to effectively manage the goods, including avoiding the goods being pulled by the bad customers and the goods being deliberately destroyed by the customers. At the same time, the goods should be replenished in time when there is a lack of goods on the shelves; in order to ensure adequate supply , Complete varieties, to store enough reserves of goods in the warehouse. Second, the management of the cashier is also an important aspect. The cash register is the place where friction and disputes are most likely to occur with customers. The service attitude of the staff, the time spent waiting for payment by the customer is too long, there is a difference in the amount to be paid, or the customer carries Unpaid goods are ready to go out of the supermarket, which can cause friction with customers. In addition, too many people in the shop can cause accidents and need to be able to help customers at any time. When off duty, cargo security requires security personnel to patrol to protect. If there are few staff, there will be no guarantee of sufficient patrol density. If there are many staff, it will increase. Supermarket operating costs.
In addition, in the supermarket chain, the distribution of the stores is usually more geographically distributed and there are more outlets. It is unrealistic for the managers of chain stores to patrol all stores in different places in a short period of time. In particular, it is impossible to understand in real time the business conditions, the flow of people, and the work of employees in each branch, and this information plays an important role in making correct decisions for managers. Therefore, in order to effectively prevent the occurrence of security accidents and strengthen business management capabilities, the construction of a set of fully functional video surveillance systems has become an increasingly necessary management tool for chain store operators.
Third, the solution
Summing up the current monitoring and application requirements of supermarkets and shops, there are two main aspects: First, the need for security protection, that is, the security of shops, warehouses, cashiers and other places; Second, business operations and management needs, that is, monitoring the work status of employees. Store traffic, shelf merchandise management and warehouse stock management.
For these two requirements, we recommend the use of NVR as the representative of network video surveillance products and solutions. First, for a single small shop, it is recommended to use a small-scale NVR platform with a minimum number of front-end access routes of 4 or more, to achieve simple local monitoring at the most economical cost, and at the same time, the management personnel can remotely manage anytime, anywhere through the network, and Once capacity expansion is needed in the future, the expansion of network products is obviously the most convenient and economical. Secondly, in monitoring systems of large and medium-sized supermarkets and chain stores, monitoring points and remote monitoring have become an inevitable requirement. For the monitoring of medium-sized supermarket chains and shops, the NVR platform with the highest number of front-end access channels and up to 64 lines or the stacking network of NVRs can be used.
For large chain stores, especially those across provinces and cities, the deployment mode of the surveillance management platform + NVR cascade network can be adopted. Each branch adopts the NVR system for local monitoring, and each branch then accesses the management platform of the headquarters through the network.
Using network video surveillance products represented by NVR, relying on the network can build a large-capacity monitoring system with distributed storage and centralized management.
1. Monitored deployment of chain stores
The cashier is the place where it is most likely to have frictions and disputes with customers. Customers who wait for payment for too long, have different amounts of money to be paid, or customers who bring unpaid goods to prepare for a supermarket, may cause friction with customers. Therefore, installing a network camera and a pickup at the corner of the cash register can, on the one hand, monitor the exchanges between the employees of the cash register and the customers and, on the other hand, monitor the receipts.
For the beautiful decoration of chain stores, without prejudice to the overall environment of decoration, it is recommended to install hemispherical network cameras in the store rack walkway. The equipment is compact and beautiful, can be well integrated with the environment, and can be well monitored shelves, corridors, The warehouse ensures the safety of the shelves and guarantees the completeness of the goods. In addition, the NVR network monitoring system also supports access deployment of wireless network cameras for special places that are difficult or impossible to wire in warehouses or racks.
For surveillance sites that need to monitor the panorama of the entire chain, it is recommended to configure an indoor network camera with pan-tilt to facilitate the monitoring of the entire shop panorama. The NVR is deployed at the checkout counter or monitoring room to form a simple monitoring center. NVR access to the monitor can watch real-time images, realize browsing and control of all monitoring points in the shop. At the same time, the NVR's internal hard disk can store videos and expand storage as needed.
Some large-scale single branch stores have multiple monitoring points and exceed the access capability of a single NVR. Multiple NVR stacking networks can be used to solve this problem.
2. Monitoring deployment of chain headquarters
At the headquarters of large chain companies, monitoring and management platforms can be deployed to achieve centralized and centralized management of all chain stores. The headquarters monitoring center can configure the decoder to decode all images to the video wall. At the same time, the company's leaders can log on to the monitoring and management platform anytime, anywhere via remote clients to achieve real-time image browsing, operation, management, download of video files, and configuration of video walls for all monitoring points. In addition, the monitoring management platform integrates the network video recording function, and can realize the storage backup of some important monitoring points through the disk array.
Finally, in the supermarket chains and shops, there is generally a complete local area network environment. Simply connect the network camera to the switch and you do not need to drag the cable directly to the NVR.
Taking into account the cost factors, the general chain stores use ADSL dial-up Internet access to connect to the Internet. In this way, the NVR can be uploaded to the monitoring and management platform of the chain store headquarters via the Internet simply by connecting the NVR to the broadband router to implement remote monitoring. After authorized managers can access the monitoring and management platform through the Internet, they can achieve real-time browsing, video download, and camera control of all NVR surveillance images of all platforms. For more qualified chain companies, VPN virtual LAN can be used. In this case, the networking is simpler. You only need to assign the LAN IP address assigned by the headquarters to the NVR to complete the networking.
First, the industry background