Application of Laser Level Gauge in Monitoring of Water Accumulation in Urban Roads I. Overview In recent years, there has been frequent occurrence of water accumulation in urban tunnels and low-lying areas under overpasses caused by heavy rainfall. In rainy cities in our country, some of the accumulated water is as high as one meter or more, and it cannot be discharged in a timely manner for a long time. People’s travel has brought a lot of inconvenience, and when it is serious, it has caused the death and disappearance of pedestrians. This phenomenon has caused the attention of municipal departments, water conservancy hydrology, and other government departments. On the one hand, it is necessary to construct and manage drainage facilities actively. On the other hand, the city’s flood prevention monitoring and management system has been established. As the core hardware of the urban flood prevention system, the water level gauge has taken measurements. The core role of water depth, good selection of water level gauge determines the quality of urban flood prevention construction. Our company has independently developed a new type of water level meter product - a laser water level gauge in conjunction with the actual needs of urban flood control systems. Second, the laser water level meter characteristics and application advantages 2.1 The laser water level meter is developed using the principle of laser distance measurement. Its characteristics are as follows: 1. The laser water level gauge adopts advanced laser ranging principle to measure the water level. Compared with other types of water level measurement products, the laser water level gauge has higher reliability and anti-interference ability, and is not affected by temperature, humidity and fog. The water level monitoring used in water conservancy and hydrology projects such as rivers, lakes, reservoirs, river courses, and channel irrigation in irrigated areas can also be used for water level monitoring in municipal projects such as tap water, urban rivers, and urban roads. 2. The accuracy of the laser water level gauge is independent of the measuring range. The full-scale measuring accuracy is ±3mm and the maximum measuring range is 70M. 3. The laser water level gauge can be used either alone or in multiple stages. The laser level gauge can be cascaded vertically to expand the measurement range according to the actual installation location and range requirements of the site, or cascaded horizontally to form a multi-point measurement network. 4 , laser level gauge system integration is high, the scene only need to buy PVC or galvanized protection tube to complete the installation. 5. The laser water level gauge adopts advanced production technology. The product has the characteristics of anti-corrosion, antifreeze, heat resistance and anti-aging, and can be adapted to various kinds of harsh measurement environments. 2.2 Application of laser water level meter in urban flood prevention 1 〠The laser water level gauge has high measurement accuracy Compared with other types of water level measurement products, the laser water level gauge has higher measurement accuracy. In the urban road water, the general water level does not exceed 1.5M. The centimeter-level error and the mm-level error are important. 2 , non-contact measurement, installation faster and more convenient Using non-contact measurement method, laser divergence angle is small, the actual installation site can use 75mm diameter PVC pipe or galvanized steel pipe as a protective tube to install, which can effectively avoid the interference of vehicles and pedestrians on the measurement effect. 3 , high system integration, The entire system integrates the laser water level sensor, RTU, GPRS communication module, solar charge controller, lightning protection module, and antenna. The integrator can complete the system installation without complicated debugging and wiring. 4 , the device is small The device is small in size and can be installed in a narrow space in the tunnel 5 , provide dedicated wireless RTU In the urban flood prevention system, functions such as LED display screen control, video image acquisition, and rainfall collection need to be integrated. Our company provides dedicated RTU equipment, which can further reduce the integrator's engineering construction difficulty. Third, the laser level gauge and other types of water level meter product comparison 3.1 Radar Water Level Meter The radar water level gauge is also a non-contact type sensor, which converts the position of the object surface by detecting the microwave reflected by the liquid surface after being reflected by the liquid surface. Advantages: External factors such as temperature, humidity, fog, etc. have relatively small influence on them, and the measurement accuracy is high and the installation is simple. Disadvantages: expensive; vulnerable to electromagnetic interference, radar wave divergence angle, easily subject to pedestrians and vehicles and other obstacles caused by inaccurate measurements, so in the urban road water monitoring system, the sensor still can not be used. 3.1 Ultrasonic water level gauge The ultrasonic water level gauge is similar to the radar water level meter measuring principle. The ultrasonic water level meter converts the liquid surface position by detecting the ultrasonic wave emitted by itself and reflected by the liquid surface. Disadvantages: The price is relatively expensive, the ultrasonic transmission of the gas components of the media outside the temperature, the influence of the larger, does not apply to a bubble or suspended medium; susceptible to electromagnetic interference, the general accuracy. The sensor still does not apply to the environment like water monitoring in urban roads. 3.1 Float water level meter Both the mechanical float and the photoelectric float are used to generate the code by means of mechanical gear deceleration to generate carry and abdicated. To generate a reliable code, Gray codes are generally used to output, and the range of the range is large, which can reach 80 meters. Advantages: simple principle, less error source, relatively low price. Disadvantages: Mechanical processing is complex, operating resistance is large, service life is short, and civil engineering costs are relatively high. In urban road water monitoring systems, this sensor is obviously not suitable for such environments. Fourth, the laser water level gauge typical parameters The main technical parameters Measuring range 0-70M Accuracy ±3mm Resolution 1mm measurement method Continuous measurement Data acquisition time 1 second Alarm method Buzzer alarm / computer display / SMS alarm Protection level IP55, can effectively prevent rain Output 4-20mA analog output, RS485, network port, RS232, USB, wireless Working power Operating supply voltage AC (187~240)V, DC: 12V~24V AC power frequency 50HZ ±2HZ System working environment Ambient temperature -10 °C~55 °C Storage temperature -10 °C ~ 60 °C (terminal) Relative humidity ≤95% RH (40±2°C) (without condensation) Fifth, the installation method 5.1 Installation Method For areas where buildings can be attached to tunnels, such as urban hydrology tunnels, the laser level gauge protection tube can be directly attached to the building using the tube card, as shown in the figure below. For areas where no buildings, such as pavements and lakes, can be attached, laser level protection pipes are directly used as supporting pipes, and control boxes, solar panels, and other accessories are installed together. l The outer diameter of the laser protection tube is greater than 75~110mm, and the steel tube can be used to support the water level meter and the solar panel. l Use bolts to install the water level controller, solar panel and LED display screen on the steel pipe, and use bolts to fix the steel pipe to the road surface. Sixth, the system list No. Project equipment name Configuration and performance indicators 1 Laser level meter probe Range: 0～50m 2 Laser level meter special float 3 Protective tube PVC pipe or galvanized steel pipe 4 Filter More detailed information on the laser water level gauge, please call Miss Li. vw dash cam,Hidden dash cam for Volkswagen,vw dash cam,Dash Cam for Volkswagen Shenzhen Future Automotive Technology Co,Ltd , https://www.futuredashcam.com
5.2 Installation Method 2