The following IEC protection classes are defined in the electrical manufacturing industry to distinguish protective grounding requirements for equipment.
Class 0 LED lighting: rely on the basic insulation as protection against electric shock, relying only on the PVC of the wire for insulation. In case the basic insulation fails (broken wires: such as broken skin when crossing the wire,) thus leading to electrocution accidents and fire hazards. Protection against electric shock will have to rely on the environment.
Class I LED lighting: protection against electric shock not only relies on the basic insulation, but also includes additional safety measures, i.e. the easily accessible conductive parts are connected to the protective grounding conductor in the fixed line, so that the accessible conductive parts are not electrically charged in case of failure of the basic insulation.
Class II LED lighting
1. Definition of Class II LED lighting.
Electrical equipment marked Class II means that the product's protection against electric shock not only relies on basic insulation, but also includes additional safety measures (such as double insulation or reinforced insulation), but there is no grounding or protection measures that rely on installation conditions.
2. Characteristics and standard requirements of Class II LED lighting.
(1) Such a luminaire may have one of the following forms.
a) A luminaire with a complete housing made of durable and robust insulating material, which encases all metal parts, except for small parts such as nameplates, screws and rivets, which are completely isolated from live parts by insulating material, so that the insulation is at least equivalent to reinforced insulation. Such a luminaire is called insulated housing type I luminaire.
b) LED lighting with strong all-metal housing, all of its internal double insulation, in addition to the use of double insulation obviously not the use of parts to strengthen the insulation. Such lamps and lanterns are called metal shell type II lamps and lanterns.
c) with the above a) and b) the combination of the type of lamps.
(4) If a luminaire with double insulation or reinforced insulation, has a unified ground terminal or ground contact, the LED lighting is a Class I structure. However, a fixed Class II luminaire used as a loop installation may have an internal terminal with which to maintain the electrical continuity of the ground conductor, which is not terminated in the luminaire. The internal terminal is isolated from accessible metal by Class II insulation.
Class III LED lighting: the power used is safe extra-low voltage, and the luminaire does not produce a low voltage higher than SELV (36v) internally: the mains power is converted to a low voltage of 36v (by adding a transformer).
