Three important rules of EMC certification 1) Law 1. The relationship between EMC cost-effectiveness ratio: The earlier the EMC problem is considered, the earlier it is solved, the smaller the cost and the better the effect. In the new product development stage, the EMC design is carried out. When the EMC test is not qualified, the cost can be greatly improved, and the efficiency can be greatly improved. Conversely, the efficiency will be greatly reduced and the cost will be greatly increased. Experience tells us that EMC design is carried out at the same time as functional design, and EMC testing is completed when the prototype and prototype are completed, which is the most time-saving and most economical. On the contrary, EMC is not considered in the product development stage. After the production is completed, it is found that the EMC is not qualified to be improved. This is not only technically difficult, but also rework, which inevitably leads to a waste of cost and time, even due to structural design and PCB design. Defects, unable to implement improvement measures, resulting in products not available. 2) Rule 2: The larger the area S of the high-frequency current loop, the more severe the EMI radiation. The high frequency signal current flows through the minimum path of the inductor. When the frequency is higher, the general line reactance is greater than the resistance, the connection to the high frequency signal is the inductance, and the series inductance causes the radiation. Most of the electromagnetic radiation is generated by the high-frequency current loop on the EUT device under test. The worst case is the open-circuit antenna form. The corresponding processing method is to reduce and shorten the connection, reduce the area of ​​the high-frequency current loop, and try to eliminate any antennas that are needed for abnormal operation, such as discontinuous wiring or long pins with components with antenna effects. One of the most important tasks to reduce radiated harassment or improve the anti-interference ability of RF radiation is to find ways to reduce the high-frequency current loop area S. 3) Rule 3: The higher the loop current frequency f, the more severe the EMI radiation caused, and the electromagnetic radiation field strength increases in proportion to the square of the current frequency f. The second most important way to reduce radiation disturbance or improve the anti-interference ability of RF radiation is to find ways to reduce the frequency f of the high-frequency current of the disturbance source, that is, to reduce the frequency of the electromagnetic wave. About EMC certification Test items The EMC inspection program for EMC certification of household electrical appliances includes electromagnetic emission (EMI) and electromagnetic immunity (EMS). Electromagnetic emission (EMI) inspection items are: 1. Conduction (CE) (150kHz ~ 30MHz); 2. Intermittent interference voltage (click) (150kHz, 500kHz, 1.4MHz and 30MHz); 3. Interference power (30MHz ~ 300MHz) 4. Harmonic current (2 to 40 harmonics) Flashing Flicker The electromagnetic immunity (EMS) inspection items are: 1. Electrostatic discharge immunity; 2. Radiated electromagnetic field (80MHz ~ 1000MHz) immunity; 3. Electrical fast transient/burst immunity; 4. Surge (lightning strike) immunity; 5. Implant current (150kHz ~ 230MHz) immunity; 6. Voltage dip and short-term interruption immunity Information required for applying for certification 1. Please refer to China Electromagnetic Compatibility Certification Center: Application Materials for the format of electromagnetic compatibility certification application; 2. A copy of the Business License for Enterprise Legal Person or a certificate of registration for applying for certification; 3. The product quality is stable and has the proof of mass production capacity; 4. Apply for the quality manual of the company; 5. A summary of the production process for applying for certified products in duplicate; 6. Product specification; 7. Product structure description in duplicate; 8. Product schematic and printed circuit board diagram; 9. The list of key parts for electromagnetic compatibility of products is in duplicate (with official seal); 10. Other relevant information required when required Lithium Battery Charger can charge 3.7V LiPo battery at a rate of 500mA,1000mA, 1500mA or 2000mA per hour. It is designed to charge single-cell Li-Ion battery or battery packs Li-Polymer batteries. The charger board incorporates a charging circuit, status LED with changetable color to let you know when battery is full. Please double check the data sheet when you need to buy a battery charger . Lithium Battery Charger Lithium Battery Charger,18650 Battery Charger,Lithium Car Battery Charger,Portable Lithium Battery Charger Meile Group Limited , https://www.hkmeile.com