Classification and Safety symbols of LED luminaires
According to the safety performance of the LED luminaires
The LED Luminaires are divided into four categories, namely:
Class 0 LED Luminaire
Rely on basic insulation for protection against electric shock-only rely on PVC for electrical wires for insulation. In the event of a basic insulation failure (a corruption of the wire: such as broken wires, aging), an electric shock or fire hazard may result. Protection against electric shock has to rely on the environment.
Class ⅠLED Luminaire
The protection against electric shock not only depends on the basic insulation but also includes additional safety measures, that is, connecting accessible conductive parts to protective grounding conductors in fixed lines, so that accessible conductive parts will not be charged in the event of basic insulation failure. (Class 0 lamp + Ground wire)
Class Ⅱ Luminaire
(1) Definition of Class 2 lamps:
Protection against electric shock not only depends on basic insulation, but also has additional safety measures, such as double insulation or reinforced insulation, but there is no protection against grounding or installation conditions.
(2) Features and standard requirements for Class 2 lamps:
- Such a luminaire may have one of the following forms:
a) A luminaire with a complete housing made of durable and sturdy insulating material that encloses all metal parts, except that small parts such as nameplates, screws and rivets are completely isolated from live parts with insulating material. Insulation is at least equivalent to reinforced insulation. Such a luminaire is called an insulated shell type I luminaire.
b) Lamps with sturdy all-metal enclosures are all double-insulated inside, except for those parts where double-insulation is obviously not feasible. Such luminaires are referred to as metal housing type II luminaires.
c) A luminaire having a combination of a) and b) above.
d)Insulated shell-type n lamps can form part or all of supplementary insulation or reinforced insulation.
e)The luminaire is still considered as a Class II luminaire if it is grounded to aid starting, rather than directly connected to accessible metal parts. The lamp cap housing and the light source’s starting band are not considered to be easily accessible metal parts, except those which are determined to be live parts by tests.
f)If a lamp with double insulation and/or reinforced insulation has a unified ground terminal or ground contact, the lamp has a Class I structure. However, if a fixed type II luminaire is used in a loop installation, it may have an internal terminal block. This terminal is used to maintain the electrical continuity of the ground conductor, and this ground conductor does not terminate in the luminaire. Internal terminal blocks are isolated from accessible metal through Class II insulation.
Class III Luminaire
The power supply used is a safety extra-low voltage, and no low voltage higher than SELV (36V) is generated inside the lamp: Convert the mains power to a low voltage of 36v (by adding a transformer).
Anti – shock level symbol description