1. Fuse used in the LED Circuit ( tube )
Since the fuse is disposable, and the reaction is slow , ineffective, cumbersome to use , so the fuse is not suitable for LED lights finished , because the LED lights especially high-power LED light such as the LED flood light and LED tunnel light are now mainly in urban engineering and lighting engineering brilliance，which requires that the protection circuit of LED is very harsh :and can immediately start protection beyond the normal use of current , so that the LED power supply path is disconnected and the LED and power can be protected ，automatically normal power after the lamp is restored , which does not affect the LED work . Circuit can not be too complicated and volume is not too large , the cost is even lower . So the use of fuses is very difficult to implement .
(2) transient voltage suppression diodes ( abbreviated TVS)
Transient voltage suppression diode is high-performance protection devices in the form of a diode. When its poles are impacted by the reverse transient high-energy , the impedance between the poles themselves is able to immediately reduce to low resistance at 10-12 seconds whose speed is a very short time , absorbing several kilowatts of power surge and clamping the voltage between the poles at a predetermined value , which effectively protect the precision components of the electronic circuits. Transient voltage suppression diodes is known as the fast response time , transient power, low leakage current , breakdown voltage deviation consistency, easier to control the clamping voltage , no damage limit, small size, etc. .
But it is not easy to find TVS device whose voltage meet the requirements in actual use. Why the light bead of LED damage is mainly because the overheating caused by current Ambassador chip . TVS can only detect overvoltage not to detect overcurrent. To select the appropriate voltage protection point is difficult to grasp , this device can not produce it is difficult to use in practice .
3 Select resettable fuse
Resettable fuse is also known as polymer positive temperature thermistor PTC, which is composed by the polymer and conductive particles. After special processing, the conductive particles constitutes the chain conductive path in the polymer . When the normal operating current through ( or the components at a normal ambient temperature ) , PTC resettable fuse with low resistance state ; when there is the abnormal current through ( or ambient temperature ) the circuit , the heat generated by the large current ( or ambient temperature ) make the polymer rapidly expanse, which will cut off the conductive path the conductive particles constitute, PTC resettable fuse is at high-impedance state ; when the overcurrent ( over-temperature condition ) disappears in the circuit, the polymer is cooled , the volume is restored normal , wherein the conductive particles form the conductive path again , PTC resettable fuse is at initial resistance state . the self-recovery fuse is of small fever at the normal operating state, its resistance is large and the heat high in abnormal working conditions, which also limits the current through it, and thus play a protective role .
In the specific circuit , we can select :
① shunt protection. LED lights such as the high power LED flood light and LED tunnel light are generally divided into many series branch . We can plus a PTC component to separately protected in front of each leg. This approach has the advantage of high accuracy , reliability protection .
② overall protection. preceded pick a PTC component in all light beads to protect the entire lamp. The advantage of this approach is simple , does not account for the volume . For commercial products, this protection results is satisfactory in actual use .
Meanwhile，there are many professional companies developing and producing LED light over the world, lead lighting is one of them，Lead lighting has been continuing to strengthen the use of certified raw materials such as LED chips, LED drivers, heat sinks, shell, etc., and improve R & D and production team, striving to adopt the best materials and technology to produce best quality LED flood light, LED tunnel light,LED street light， LED tube light and other indoor and outdoor lighting, using highly integrated high-brightness COB as the light source of the LED flood light and LED tunnel light and other outdoor lighting，adopting high brightness SMD LED as the light source of the LED tube light, the low-voltage constant current driver ensure the alternating current can be convert into direct current so that improve the energy use and reduces the stroboscopic effect stimulating the human eye, fully guarantee octahedron illuminated area of LED flood lights and bright light to adapt to outdoor open environment ，the soft and bright light of the LED tunnel light and LED street light and LED tube light makes us safe driving in tunnels and enjoy work and study.As an ISO 9001:2000-certified factory,the lead lighting can meet the strict standards of CE, RoHS, FCC certificate, these strict producing standards guarantee our products distribute smoothly both in domestic and international markets.