Combining the longitude and latitude to calculate the switching time 70 thousand LED lights on the city of Hong Kong

With the winter approaching, the dark time is getting earlier. Many citizens reflect the light switch time in front of the door, sometimes early and late, and do not know what is the reason. Yesterday (3) on the morning, the reporter visited the City Management Bureau lamp control center, the 70 thousand LED road lights in the opening and closing of the computer automatic control, according to the Beijing light time combined with Yantai latitude and longitude automatic adjustment, if special weather conditions, can also be manually switched.

Conversion of light time according to latitude and longitude

Yesterday (3), 9 o'clock in the morning, located in the light control center near the small Mount Huangshan in Zhifu District, the more than 70 thousand LED street lights in the main road of the Zhifu District, the coastal road, the Guan Hai Road, Hong Kong City Street and other urban main roads are all controlled and closed here.

The big screen shows the time of the day's switch light. "This morning's turn off time is 6:04, and the evening light is 17:01." Yuan Yongzhi, the director of the light control center, told the reporter. It is understood that the 365 days of a year, the daily switching lights are different.

So what is the time to determine the switching light per day based on what? Yuan Yongzhi told reporters that, under normal circumstances, Beijing will determine the light time of the day, the system will be calculated according to the latitude and longitude difference, automatically determine the local light time. From the light time curve of the last few days, the reporter saw that the light time of each day was 1-2 minutes earlier than the previous day, and the corresponding light time was 1-2 minutes later than the previous day. "The latest light should be the summer solstice, basically until 8 p.m., the first in the winter solstice, about 4:30 in the afternoon, nearly 4 hours." However, if there is a certain offset in the light of the rainy day, it needs to be adjusted in real time according to the specific weather conditions, such as the rainy weather in recent days, the relative early days in the dark, the adjustment of the special person in the management department and the early opening of the street light according to the situation, so as to ensure the convenience of the citizens to travel. When special weather, extreme weather, or major activities are encountered, the staff will also control the opening and closing of road lights at any time according to the actual needs.

The control center can see each street lamp

"At present, our city is a transformer control over a kilometer of street lights switch, so 40 - 50 miles of street lights in one kilometer can only be at the same time at the same time." In the future, Yantai will gradually introduce a single light control system. At present, 540 sets of pilot sets have been installed in the Tong Shi Nan Road. From the control center, it can clearly see which light is not bright so as to organize maintenance. In recent years, the management office has changed the street lamps of the main road, such as the airport road, the view sea road, the two road and so on. The old lamp head of the old street lamp is all replaced by the LED street lamp with good energy saving and good lighting effect, which greatly improves the lighting situation at night. "Take two road as an example, is an important section of the city, the street lamp is installed in 2005. The ordinary street lamp is replaced about 8 years, the old street lamp of two street has reached the service life, and the lights of the overdue service have the shortcoming of small brightness and insufficient energy saving. The new LED light source has the advantages of high light efficiency, low energy consumption, long service life, good color display and so on. The 150 Watt LED street lamp is equivalent to the lighting effect of 500 watts sodium lamp.

The reporter learned from the management department that the relevant departments will work out the LED street lamp replacement plan every year. From the main and secondary roads to the streets and lanes, the energy-saving lamps are gradually popularized.

Automatic alarm of cable being cut off system

Street lamps often suffer from "black hands", someone smashed, a car crashed, and a long time used to bask the quilt. The reporter learned that the most serious damage was the cable theft, so the street lamp has been studying how the cable is burglarproof for the last few years.

Yuan Yongzhi introduced that the principle of cable burglar theft is that the power supply of the street lamp has formed a weak circuit. When the system works normally, that is, when the cable is not stolen, the circuit should have 1 to 3A current in general. After the monitoring system of the street lamp is magnified automatically according to the ratio of the current transformer, it can be detected. Dozens of amperes or even larger currents. If the main cable is cut off during the day or at night, the current of the circuit will disappear, and the cable theft situation will be prompted by the street lamp monitoring system at the first time after the remote detection.

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