1. Check whether the size of the bulb package has the name of the manufacturer, address, telephone number, implementation standard, trademark number, packaging design, beautiful printing, and whether various brands are matched by well-known automobile factories.
2. Appearance: the visual filament, lamp cap and bubble shell components shall be correct and symmetrical; the welding point shall be smooth and solid, and the lamp cap shall be bright without scratch; the bubble shell shall be transparent without obvious air pipe and bubble; the filament shall be regular, neat and not deformed; the lamp core shall be neat and the bending shall not exceed 5 degrees; the adhesive for the joint of bubble shell and lamp head shall not be exposed and the bonding shall be uniform; The steel seal of lamp cap is clear, brand, specification, without mark, there are products.
3. Mechanical strength: use the left hand and right hand (wearing gloves) to take the lamp cap and bubble shell screws (force not more than 15N) to know whether the lamp cap and bubble shell are firm;
4. Photoelectric parameters: qualified instruments can detect whether the current, luminous flux and life of the bulb meet the relevant standards to determine whether they are qualified.
5. When ordinary consumers buy light bulbs, they have mastered the characteristics of the first three bulbs and can buy qualified products.
Features of poor quality light bulbs:
1. The packaging design system is rough, the imprint is not clear, no factory name, no address, no telephone, no implementation standard.
2. The appearance is dirty, the filament is black, twisted, the inner wire is oxidized black or crimson, the lamp cap is rusty and dull, it has a clear curved head, curved shoulder and curved core, and the lamp holder has no steel type or specification, but no brand.
3. The mechanical strength is low, the bubble shell is thin and fragile, and the lamp cap is thin. The head and skin collapse immediately with nails, and the lamp cap and bubble shell are exposed or uneven.
4. Most of the photoelectric parameters are unqualified.