there is no necessary to worry about led street light in lighting days
Time：2014/7/22 keywords：led street light
LED Street Light plays an increasingly important role in urban lighting, lightning protection under the knowledge to understand the following. Produced by lightning is divided into three categories:
1, direct lightning, contains enormous energy. Has great destructive power. Will result in the following three effects: huge rich currents flow in a few microseconds, so quickly pick up the high ground, resulting counterattack accident, endangering the safety of persons and equipment; lightning current to generate strong electromagnetic waves, power lines and signal lines high pulse voltage sensing; lightning current flows through the electrical equipment occurring high heat, causing a fire or explosion.
2, conduction thunder, distant lightning struck a high voltage line or by electromagnetic induction occurs from outdoor power lines and communication lines spread to the building interior electrical equipment.
3, lightning, frequent discharge between clouds strong electromagnetic waves cause common mode and differential mode interference, affect the electrical equipment running. Similar effects and lightning damage.
So I turn how to prevent the occurrence of lightning it?
First, the external and internal lightning protection lightning combine now generally led street light outside is conductor materials, their equivalent of a lightning rod, it is necessary deflectors and ground network design, these systems constitute the external lightning protection system. The system can be avoided due to direct lightning caused fires LED Lights and personal safety accidents. Internal lightning protection system is a street light inside through the ground, set the voltage and maintenance of equipment and maintenance. The system prevents lightning and other forms of over-voltage invasion, causing the power to destroy, which is between the external lightning protection system can not guarantee that the two are mutually reinforcing and complementary. Internal lightning protection system on many devices such as housing, cable and out of the maintenance area, metal pipes, etc. must be connected to an external lightning protection system or set overvoltage protection, and equipotential connection.
Secondly, mine and other potential connection to completely eliminate the destructive potential difference caused by lightning, power lines, signal lines, metal pipes and other devices must be used to maintain pressure equipotential bonding at the interface of each inner protection zone should partial equipotential connection, various local equipotential connection to connect to each other, and finally connected with the main equipotential place.
Then, set the lightning maintenance area, currently led street light in addition to the power supply, but also to set some communications equipment used to control the lights off and the brightness and power of these devices are to be resettled in a lightning maintenance area, maintenance area directly affected by Shell Shield . Electromagnetic field here is much weaker.
Finally, high-quality protective equipment - lightning and overvoltage protection module module SPD‘s role is to be maintained within the shortest possible time (nanoseconds) and other potential systems connected to the system, so that each port equipment such potential. While the great pulse energy circuits generated by lightning released by the short route to the earth, to reduce the potential difference between the ends of each interface devices, which play a role in maintenance of equipment. LED lights are not as long as the power supply module is designed in accordance with the above requirements, and must undergo a rigorous inspection order: 1 with a constant voltage output function or functions with constant current output control device or a combination of both functions should be used GB19510.12/IEC61347- 2-13 Ping specification test. Control device only has control LED light and dark, flashing, color changing function of two pairs of logic should be used GB19510.12/IEC61347-2-11 peace specification test.
Practice has proved that through the product within the scientific design, strict testing and protection of the common external connected devices, not only to ensure that the system is not being led street light lightning damage, and put an end to the lightning to power supply common mode and differential mode interference.