Hot discussion security equipment lightning protection

In heavy rain seasons, it is particularly important for citizens to pay close attention to warning information and master basic defense measures. If storm orange or red warning signals are issued, outdoor personnel should pay close attention to heavy rain and traffic information, away from high-voltage power equipment such as overhead lines, towers and transformers, avoid crossing flooded areas, and contact bare wires, resulting in electric shock; cancellation of heavy rain warning signals It does not mean that it is safe. Personnel in areas prone to secondary disasters such as river courses and dangerous slopes must still strengthen safety precautions.

Shenzhen recorded the strongest rainfall within an hour in 60 years. It is expected that convective weather will still be more active in the short term. From noon 30 to noon 31, large areas of Guangdong were hit by heavy rain. Shenzhen No. 31 was in the morning like a dusk. After a short break, it rained again. During the 30th thunderstorm, 9119 lightning flashes were recorded within 5 hours. Two people have been reported to have died as a result of the disaster. The meteorological department said that 114 millimetres of rainfall in local areas within one hour of the heavy rainfall once recorded was the strongest hourly rainfall intensity in 60 years.

What was the concept of 9119 lightning flashes recorded during 5 hours of a thunderstorm? We have to attach importance to such thunderstorm weather. From the perspective of security, the lightning protection settings for security equipment are non-negligible processes and designs, and monitoring equipment for outdoor installations, especially those mounted on high-rise buildings such as heads Especially need to increase the function of lightning protection!

Security equipment lightning protection technology collection

The security system includes front-end information collection equipment, transmission lines and back-end storage and monitoring centers, and lightning surge protection for each part must be treated differently.

1, front-end equipment protection

The front-end equipment is mainly divided into indoor and outdoor. If the outdoor equipment is far away from the building and is not within the effective protection scope of the building's direct lightning protection device, it is necessary to consider installing a lightning protection device; if it is already in the lightning receptor (lightning rod or other Front-end equipment within the scope of protection of existing lightning protection systems of high-rise buildings or lightning conductors is generally no longer considered as direct lightning protection. Such as outdoor cameras, within the effective protection range of the building air-termination device, in order to prevent lightning induction, the camera power line and signal line led along the telephone pole should be put in the grounded steel pipe to achieve the shielding function, in order to prevent lightning induction. Currents intrude into the front-end equipment along the line, and corresponding lightning arresters should be installed on each line in front of the equipment. The lightning arrester must be connected to earth and ensure the grounding quality. Otherwise, the arrester is equal to no equipment.

It is worth noting that the isolated isolated pole camera should be equipped with an independent lightning rod to prevent direct lightning, but the pole camera should be placed within the effective protection scope of the independent lightning rod, and the distance between the independent lightning rod and the pole camera should be as far as possible (guaranteed Under the premise of effective protection, the influence of the strong magnetic field of the magnetic discharge current to the camera cable on the lightning conductor shall be avoided. The camera pole and the mounting bracket are preferably made of steel (there is wind-resistant steel, It also has good electrical conductivity and shielding performance, and also has to do very good grounding (ground resistance to achieve lightning protection requirements); indoor front-end equipment needs to be lightning-induced surge protection, video surveillance system through the conventional three-in-one (video + control + power supply), 2 in 1 (video + power supply) lightning protection products, protection of front-end equipment such as camera power, video, PTZ control.

2, transmission protection

Mainly include transmission signal lines and power line protection. Transmission lines should be strongly recommended for direct burial. Overhead is not recommended because overhead lines are the most vulnerable to lightning strikes. If non-airborne is not available, in order to avoid damage to the end-to-end equipment, the overhead cable itself should be strengthened. For example, use high-quality shielded cables, increase the density of shielded copper mesh, and shield the copper mesh from grounding; try to get the overhead line Walking along the building, but away from the flat conductors of the lightning conductor, grounding should be done on each pole during transmission. The overhead cable overhead cable and the overhead metal cable should be grounded. Both the signal source and the power supply at the input should be connected to the appropriate arresters.

3, back-end storage and monitoring center equipment protection

From the standpoint of direct lightning protection, the building where the monitoring center is located should have lightning rods, lightning conductors, or lightning protection nets that prevent direct lightning strikes. From the perspective of inductive lightning protection, various metal pipelines entering the monitoring center should be connected to anti-radar grounding devices. When the overhead cable line is directly introduced, an arrester should be installed at the entrance to the house, and the cable metal outer sheath and the self-supporting steel cable should be connected to the grounding device. The monitoring center shall be equipped with an equipotential connection box and lead out with a copper bar. It is best to walk around the wall of the monitoring center (under the anti-static floor), and protect the grounding end of the arrester, the PE line, the equipment protection ground, and the anti-static electricity. Metal pipe slots, etc. are all connected to the equipotential copper bar to prevent dangerous potential differences. Copper wires are used for grounding wires of various types of surge protectors (arresters), etc., and are electrically connected to the equipotential copper bar with the shortest and thickest wire diameters possible.