Table 1 recent street lamp cable theft loss urban area time economic loss (million) Shanghai 2005 11 months Hangzhou Wuxi Ningbo Tianjin Guangzhou 2003 40 days in the first half of 2004 Nanjing Xiamen Yantai in the first half of 2004 Shenzhen 2, street lamp cable theft society In addition to direct economic losses, the theft of streetlights has brought great social harm to urban security: security and traffic safety are affected: streetlights are out of power in large areas, and cars are driving on the roads, encountering darkness every few minutes on average. More than 90% of such power failures are caused by the thief smashing cables. In the case that the street lights are not bright, the proportion of potential traffic accidents and theft cases will rise, and the resulting social security problems will also emerge in an endless stream. Life safety is threatened: the cutting port of street lamp cable and many exposed wire ends are all charged. If passers-by pass by, or step on or hit these wire ends, the possibility of electric shock is extremely high. In severe cases, electric shock may occur. Self-security is threatened: in addition to threatening the personal safety of the residents, the thief itself has an example of electric shock while in the process of theft. Theft of transformers and the theft of high-voltage wires have caused many instances of personal injury and death. 3. Development trend of street lamp cable theft In recent years, due to the price increase of non-ferrous metals, the scale of cities has increased, the number of migrants has increased, and the situation of street lamp cable theft has accelerated. According to the reported data, the loss of streetlight cable in Hangzhou was 800,000 in 2003. Yuan, in 2004, was 2.88 million yuan. In 2005, due to the rapid deterioration of cable sneak, it became a direct loss of 5 million yuan for a thief in the heart of every lighting management. The trend chart is shown in Figure 1. Can be very sick. It can be seen that the damage caused by cable theft is more than 30% per year. Figure 1. The trend of street cable stealing in Hangzhou from 2003 to 2005 and the adoption of corresponding technical measures. The current situation of urban street lamp cable theft is deteriorating, and the management department is helpless. Take appropriate technical measures and measures as soon as possible to curb the spread of this trend. The use of lighting cable anti-theft alarm technology, through the all-weather real-time monitoring of street light cables, timely detection of anomalies, reduce or even prevent cable theft losses, is a better anti-theft solution. Second, the current technology and the special characteristics of street lighting. At present, some manufacturers in China have produced the corresponding street lamp cable alarm system, trying to solve this problem. These products have adopted the method of power carrier communication or detecting cable characteristics to carry out theft detection. . However, due to the following particularities of streetlight cables, these techniques have a high rate of false positives or are unreliable. The lighting line is energized after lighting at night, and the power is turned off after the daylight is turned off. It is required to achieve anti-theft alarms all day long; 'Each light source cable is connected with tens of micro-method compensation capacitors in parallel with each light source. The traditional power carrier signal strength is indexed with distance. The law is declining, resulting in very unreliable power carrier communication; the self-extinguishing phenomenon occurs before the end of the high-pressure sodium lamp (always flashing and ignoring, separated by several minutes), resulting in uncertainty of cable current; street lamp cable buried in the ground, after long-term work Leakage caused by rain and moisture; the failure of the lighting equipment often leads to local extinction, and the current changes greatly. It is difficult to distinguish whether the cable is stolen or the light is off according to the current. Third, a new street lamp electric tank 1 into the technology In order to solve these problems, we applied the following street lamp cable anti-theft alarm system. It is a combination of traditional anti-theft technology, wireless alarm technology, power electronics technology, computer data processing technology, multimedia technology and cable detection technology. It has both reporting function and line status detection function. The false alarm rate is extremely low. It also adds the function of remote reporting. The system is divided into two levels. Monitoring center and monitoring front end. Monitoring front-end: including several cable anti-theft hosts (referred to as "hosts"), each with a number of cable anti-theft ends (referred to as "ends"). The host is set in the monitoring front end and has a wireless communication unit (default is GSM communication). The main unit is connected to the low voltage outlet of the power cable, and the number of ends is determined by the number of outlets on the low voltage side. The end is connected to the host of the monitoring terminal through the power carrier (the distance is not more than 3000 meters), and the single detector is connected to one of the low-voltage outlets to detect the condition of the line. Collect the working status of each point, realize the data recording and management, and perform data statistics. Once an abnormality is found, the fault can be located in time, and the status quo is reported to the relevant personnel. The management personnel can actively query the running information of the monitoring front end at any time and anywhere. The alarm signal has different shape aging, no effect, no false alarm, no effect, self-extinguishing, no effect, false alarm, no effect, no light, no effect, no false alarm, no false alarm, no multi-branch cable anti-theft, can not be switched, the light is reliable. False positive report without error. Key technology General power carrier technology is not suitable for street lamps with complementary capacitors. The technology is simple and mature. It is especially used for street lamp cable. Low cost, moderate reliability, low false alarm rate, high battery and low power. Anti-theft technology comparison project Power carrier method Cable impedance method The top-end cable of the solution is installed with "host" on both ends of the cable and the host is installed at one end of the cable. The two sides of the tail-mounted DC link cable are respectively installed with "host" and principle carrier communication detection cable on and off. According to the DC loop, the host uses the "constant current limiting source to apply low voltage to cable" technology and the "constant current source carrier that can overcome the cable leakage and compensating capacitors" technology to supply power to the end battery. The battery maintenance workload is large without battery. Power from the host, no battery can overcome the compensation capacitor can not communicate distance In the power supply range, the communication life can be transmitted frequently, the power is large, the component life is short, the cable short circuit has no effect, the cable leakage can be detected, and the cable leakage has no effect, resulting in no alarm. No impact on the resistive load, no impact, no report, no detection, and alarm multi-branch Cable anti-theft can not be able to switch lights when the reliability is easy to report falsely report the cost of high and low moderate reliability low false alarm rate high low five conclusions This system is currently in the bridge lighting lighting system of the Hangzhou Electric Power Bureau street lamp management office After getting a trial, he successfully issued a cable stealing signal several times. After the staff rushed to the scene, they prevented the thief from stealing the cable and saved huge economic losses. The system is accurate and has a very low false positive rate. It is a good helper to prevent street lamp cable theft. High-profile facilities to steal legislation to severely punish cable "groundhog" Online Today Morning Post, more than 70 landscape street lights are all "opening the belly" Anti-greedy black hand> 749.shtml, a new daily newspaper in the Northern Network, street lights stolen, a loss of 3 million people a year, please report quickly http://, <Xinglin blockbuster The street lamp was stolen and the loss of more than 4 million municipal departments could not be prevented. Foam Baby Pillow,Baby Head Pillow,Memory Foam Baby Pillow,Baby Head Shaping Pillow Nantong Wenbo Foam Art Co.,Ltd , https://www.ntwbmemoryfoam.com