Classification of protection against electric shock
Source: Date:2010-03-12 16:31:44
For the sake of electrical safety, all live electrical parts of the lamps must be isolated by insulating materials, etc. this measure to protect personal safety of the lamps is called anti electric shock protection. According to the method of anti electric shock protection , the lamps can be divided into four categories: 0, I, II and III. (see the table below)
Protection level | Main performance of lamps | Application description |
Class 0 | Protection depends on basic insulation, i.e. insulation between accessible parts and shell and live body | It is applicable to the occasions with high degree of safety, and the installation and maintenance of lamps are convenient. Such as the ceiling lamp and ceiling lamp under the conditions of dry air, less dust and wood floor. |
Class I | In addition to the basic insulation, the accessible parts and the shell are equipped with grounding devices. Once the basic insulation fails, there will be no danger. | Used for metal shell lamps, such as projection lamps, street lamps, courtyard lamps, etc., to improve the safety level. |
Class II | In addition to the basic insulation, there are supplementary insulation, such as double insulation or price enhanced insulation, to improve the safety, | With good insulation and high safety, it is suitable for lamps and lanterns with poor environment and frequently touched by people, such as desk lamps and portable lamps. |
Class III | Ultra low safety voltage (AC effective value<50V),and no voltage higher than this value is generated in the lamp. | The lamps are highly safe and can be used in harsh environments, such as machine tool working lamps and children's lamps. |
