Generally, bulbs use aluminum radiators. The disadvantages of such bulbs are heavy weight, and because aluminum is electrically conductive, it is not easy to pass CE, UL and other safety certifications if powered by a non-isolated constant current power supply. Because the high voltage of 4000V or more is required for these certifications, and this voltage is completely applied to a very thin insulating cloth of the aluminum substrate, usually the withstand voltage of the aluminum substrate rarely exceeds 3000V, which becomes a bottleneck for certification. The withstand voltage of the insulated plastic heat sink can easily exceed 4000V. This makes it easy to pass these safety certifications when using a bulb with a plastic heat sink while using a non-isolated constant current source. Most people think that a metal radiator must be used to dissipate heat. This concept is not correct. Although the heat conduction of metal is indeed better than plastic, the main purpose of the outer casing radiator is to dissipate heat into the air. When the thickness of the heat sink is less than 5 mm, heat conduction is not a major problem. As long as the thermal conductivity of the heat sink material is greater than 5W/mK, the heat dissipation is mainly convective heat dissipation (see Figure 1). There is no difference between metal or plastic. Some good thermal conductive plastics doped with ceramic powder can easily achieve a thermal conductivity greater than 5W/mK. Figure 1. Thermal conductivity greater than 5W/mK and thickness less than 5mm. The heat dissipation capability of the heat sink is completely determined by convection. Moreover, plastic is superior to aluminum in terms of radiation heat dissipation. So using a plastic radiator for a bulb is a good choice. The bulb developed by Longmao has an input power of 8W and an efficiency of over 88%. The actual test shows that the heat dissipation effect is satisfactory. And its weight is about 30% lighter than the bulb of a general aluminum radiator. The product is currently in volume production. Cummins 0-20KW Diesel Generator Cummins 0-20Kw Diesel Generator,Cummins Portable Power Generator,Cummins Open Type Power Generator,Cummins Container Power Generator Shanghai Kosta Electric Co., Ltd. , https://www.generatorkosta.com
