In the current GB7000.1-2002 standard, lamps are divided into four categories according to the type of electric shock protection, namely, class 0 lamps, class I lamps, class II lamps and class III lamps.
1. Class 0 lamps class0lnminaire
Lamps that rely on basic insulation as protection against electric shock. This means that the accessible conductive parts of the luminaire (if any) are not connected to the protective conductor in the fixed line of the facility, and in case the basic insulation fails, it has to rely on the environment.
2. Class I lamps class1luminaire
The electric shock protection of lamps not only relies on basic insulation, but also includes additional safety measures, that is, connect easily accessible conductive parts to the protective wires in the fixed line of the facility, so that the accessible conductive parts will not be charged when the basic insulation fails.
3. ClassⅡluminaire
Protection against electric shock not only relies on basic insulation, but also has additional safety measures, such as double insulation or reinforced insulation, but no protection measures that depend on grounding or installation conditions.
4. ClassⅢluminaire
The protection against electric shock relies on a type of lamp whose power supply voltage is a safety extra low voltage (SELV), and which does not generate a voltage higher than SELV. Anti-shock protection is an important indicator for evaluating the safety characteristics of lamps. However, the previous random inspections of the General Administration of Quality Supervision, Inspection and Quarantine show that the unqualified anti-shock protection of lamps and lanterns in our country ranks in the forefront of various unqualified items in random inspections. It can be seen from the standard definition that the anti-shock protection provided by Class 0 lamps is the lowest. In order to ensure that Class 0 lamps can be used safely, the current standards stipulate how to use Class 0 lamps. For example, Article 1.2.21 of the standard stipulates that Class 0 lamps are only applicable to ordinary lamps; Article 2.2 stipulates that lamps with a rated voltage exceeding 250V should not be used. Luminaires that are classified as Class 0 and used under severe conditions should not be classified as Class 0, and those for track installation should not be classified as Class 0. Class 0 lamps rely on basic insulation as protection against electric shock, and the use environment is limited to non-conductive places. However, in the actual use process, it is more difficult for users to identify the types of lamps one by one, and also to identify whether the use environment is a non-conductive environment. Based on this consideration, the new standard eliminated Class 0 lamps.
