As the market scale of electronic and electrical products is rapidly climbing, quality control of electronic and electrical products has received widespread attention and importance. Various evaluation standards, represented by safety, electromagnetic compatibility, reliability and energy efficiency, set requirements for raw materials, components, functional modules and finished products of various types of electrical and electronic products, such as household appliances, information technology products, wireless communication products, audio and video products, lighting appliances, power tools, toys, educational equipment, smart homes, financial and settlement products, vehicle electronics products and medical devices.