First, the status of LED North American standards
LED energy-saving lamps as a new product, the current North American product safety standards are not specifically for the technical requirements of such products, LED product testing has become a subject of the industry. US UL laboratory for the current situation in this industry, is organizing the preparation of LED energy-saving lamp safety certification standards UL8750, this standard is still draft, not formally adopted as a certification standard. Therefore, the LED energy-saving lamp certification test problem, has not been completely resolved.
The basic principle of LED energy-saving lamps is through the switch-type power supply module will be AC power conversion DC to power supply to the light-emitting diode work. According to the basic principles and structural characteristics of LED energy-saving lamps, the United States MET laboratory proposed a transitional testing program at this stage: the use of traditional energy-saving lamps US certification standards UL1993 (corresponding to the Canadian standard CAN / CSA-C22.2No.0, CAN / CSA-C22.2No.74), and the power module standard UL1310 or UL1012 (corresponding to the Canadian standard CAN / CSA-C22.2No.107) on the LED energy-saving lamps for testing and certification.
Second, the detection of technical points
The following based on UL1993, UL1310 and UL1012 standards, LED energy-saving lamp certification test key issues, do some elaboration.
LED energy-saving lamps can be made into a variety of shapes to fluorescent lamp-type LED energy-saving lamps, for example, its shape with the ordinary fluorescent tube, fluorescent tube from the tubular transparent polymer case and light-emitting diode package in the inside. Transparent polymer housing in the product to play a fire and anti-electric shock function. According to the standard requirements, energy-saving lamp shell material to be more than V-1 level, so transparent polymer shell to be used V-1 grade above the material.
It should be noted that the product shell to achieve the required V-1 level, the thickness must be greater than or equal to the required thickness of the raw material V-1 level, fire rating and thickness requirements can be found in the raw material UL yellow card The The actual test found that manufacturers in order to ensure the brightness of LED lights, transparent polymer shell is often made very thin, which requires engineers to ensure that the material to ensure that the material required to achieve the level of fire protection thickness. Because different raw materials have different thickness requirements for the same fire rating, some raw materials can meet higher fire rating requirements at smaller thicknesses. Manufacturers can choose the right raw material to make the product shell.
2. Drop test
According to the product standard requirements, the product to simulate the actual use of the process may occur in the fall of the situation for the drop test, the product from 0.91 meters high to the hard board, the product shell can not be broken and exposed to the internal dangerous parts. When the manufacturer chooses the material to make the product shell, it must consider this strength requirement.
3. Electrical strength
The transparent housing encloses the power module inside, and the transparent housing material must meet the electrical strength requirements. According to the standard requirements, based on the North American voltage of 120 volts, the internal high-voltage live parts and the shell (covered with metal foil test), to withstand AC 1240 volts of electrical strength test. Under normal circumstances, the product shell thickness of 0.8 mm or so, you can meet the requirements of the electrical strength test.
4. Power module
Power module is an important part of LED energy-saving lamps, power modules are mainly used switching power supply technology. Depending on the type of power supply module, you can consider testing with different standards for certification. If the power supply module is class II power supply, this can be tested with UL1310 certification. Class II power supply is the use of isolation transformer, the output voltage is lower than the DC 60 volts, the current is less than 150 / Vmax amps power. And non-class II power supply, the use of UL1012 to test certification. The technical requirements of these two standards are very similar, can refer to each other. Most of the LED internal power supply module is the use of non-isolated power supply, power supply output DC voltage is greater than 60 volts, it is not applicable UL1310 standard, and for UL1012
5. Insulation requirements
As the LED energy-saving lamps internal space is limited, in the structural design, pay attention to dangerous parts and accessible metal parts between the insulation requirements. Insulation can be space distance and creepage distance, it can be insulated. According to the standard requirements, dangerous electrical parts and accessible metal space between the distance to reach 3.2 mm, creepage distance to reach 6.4 mm. If the distance is not enough, you can add insulation as an additional insulation, insulation film thickness is greater than 0.71 mm, if the thickness is less than 0.71 mm, the product will have to take 5000V high voltage test.
6. Temperature rise test
Temperature test is a product safety test will do a project, the standard of different components have a certain temperature limit. In the product design stage, manufacturers should pay great attention to the product heat dissipation, especially for certain parts (such as insulating films, etc.) should pay special attention.
If the unit is working long term at high temperatures, it is liable to damage, resulting in fire or electric shock. The power module inside the lamp is in a confined space with limited heat dissipation. Therefore, the manufacturer to select the components, we should pay attention to select the appropriate component specifications, to ensure that the components work in a certain margin, so as to avoid long-term components in the near full load conditions and overheating.
LED energy-saving lamp power supply module installed in the shell inside, space is limited, and some manufacturers in order to save space, the plug-type component surface welding on the PCB, this approach is unacceptable. These surface-mounted pin-type components are likely to fall off due to Weld and other causes, causing danger. So these elements as much as possible to take jack welding. If you have to take the surface welding, you have to use this component with glue fixed, etc. to provide additional protection.
8. Fault test
Product failure testing is a test project that is critical to product certification testing. This test project is a short circuit on the line or open some components to simulate the actual use of the process may occur in order to assess the product in a single fault conditions of security. In order to meet this safety requirement, the product should be designed with a suitable fuse at the product input to prevent overcurrent from the output short circuit or internal component failure, resulting in a fire hazard.
Third, the factory inspection
North American product certification to the factory inspection, factory inspection, including the first factory inspection and follow-up inspection. If the factory is the first time to apply for North American product certification, will have to conduct the first factory inspection. The first factory inspection is mainly for the factory quality assurance system, requiring the factory has a perfect quality assurance system to ensure that the product quality is effectively regulated and guaranteed. If the factory has been established according to ISO9000 quality management system, and passed the ISO9000 certification, basically can meet the requirements of the first factory inspection management system. If the factory does not pass the ISO9000 certification, it will have clear procedures in the aspects of raw material procurement, incoming inspection, inventory management, product design, engineering change, production line test, instrument calibration and complaint follow-up. Follow-up inspection is mainly for product structure inspection and production line product testing and so on to ensure that the production line of the product structure and certified samples consistent, and through the relevant production line test. After the product has passed the test certification, the manufacturer must strictly follow the structure of the certified sample and the component list to produce the product. Any changes that may involve the safety of the product must be notified to the certification body for evaluation. If necessary, it is possible to carry out re-testing and reporting changes. The test report of the product has a clear requirement for the production line of the product. The manufacturer must perform the relevant tests as required, such as high voltage test and ground continuity test.