LED lamp blue light hazard assessment method

The 8th edition of IEC 60598-1 first revised the standard with LED as the focus of attention. The revision of the standard takes the optical, electrical and structural characteristics of the LED luminaire as considerations, supplementing the marking and structural requirements for the blue light hazard of LED luminaires. The operating voltage of the light source in many LED lamps is characterized by extra low voltage, which stipulates the insulation requirements of LED lamps. At the same time, the structure and electrical strength test provisions of the luminaire have been revised because the light source is not replaceable and the overvoltage protection device may be used in the luminaire circuit.

At present, the basic standard for photobiohazard of lighting products in the IEC standard system is IEC 62471 series standard. Since LED lighting products involve product chains such as LED chips, LED packages, LED modules and LED lamps, if LED lighting is used in various product stages. The retinal blue light hazard evaluation of the product will bring a lot of repetitive work. In this regard, IEC/TC34 published the technical report IEC/TR 62778, which aims to evaluate the blue light hazard of LED light sources and lamps using IEC 62471. The IEC standards for the safety of LED light source products and LED lamps in the process of development are all cited in the evaluation method of IEC 62778, which puts safety requirements on the marking and structure of LED products.

This paper takes the marking and structural requirements of the blue light hazard of the luminaire considered in the revised IEC 60598-1 8th edition CDV document as the entry point, and introduces the relevant requirements of IEC 61471 and IEC/TR 62778 standards, as well as the general blue light hazard of the luminaire products. method.

I. Introduction to the relevant requirements of the CDV document of the 8th edition of IEC 60598-1

In the 8th edition of IEC 60598-1, the limitation of the retinal blue light hazard of the luminaire product is specified. By specifying the marking and structural requirements of the luminaire product, the blue light hazard generated by the luminaire will not reach the level of safety hazard.

(1) Mark (3.2.23)

The provisions in the standard Chapter 3 mark include:

1. For portable and portable LED lamps

According to IEC/TR62778, for portable and portable luminaires with RG1/RG2 (Ethr) extreme conditions, the symbol “Do not stare at the light source” is recommended (see Figure 1). This mark shall be marked on the luminaire and shall be visible after the luminaire has been installed. The height of the mark shall not be less than 5 mm.

2. Lamps that can directly see the light source during maintenance

The luminaires contain LED light sources with RG1/2 (Ethr) extreme conditions according to IEC/TR 62778 and can be seen directly during maintenance of the luminaire and should be marked with the symbol “Don't stare at the light source” (see Figure 1). This mark shall be marked on the outer surface of the luminaire that is visible when the luminaire is being maintained, or on the reverse side of the hood that is moved when the light source is replaced. The height of the mark shall not be less than 5 mm.

3. For fixed luminaires

According to IEC/TR 62778 classified as fixed luminaires with RG1/RG2 (Ethr) limit conditions, when Xm is the distance at which the RG1/RG2 (Ethr) limit condition occurs, the manufacturer's instructions supplied with the luminaire shall provide "should be The fixture is placed in a position that is not expected to be staring at the fixture at a distance close to Xm." Text. This requirement only applies when the distance from the luminaire is 200 mm when Ethr is reached.

According to 6.1 of IEC TR62778, Xm is the distance between the light source and the observer's eye, which is derived from the calculation of the luminaire illumination distribution measurement.

(2) Structure (4.24.2)

For the blue light hazard group given in IEC 62471, the use of various types of light sources in luminaires is specified in Chapter 4 of IEC 60598-1.

1. Do not use LED light source exceeding RG2

Luminaires with integral LED or LED modules shall be evaluated in accordance with IEC/TR 62778 “Applying IEC 62471 to assess the blue light hazard of light sources and luminaires”.

It is hoped that LED light sources larger than RG2 that are harmful to blue light will not be used. More cumbersome management requirements are required for this type of light source.

At the same time, the standard prompts, because this product has not used the RG3 LED light source luminaire in the market, so it has not been proposed yet, if necessary, it will be developed in the future.

2. For the case of classification as RG0 or RG1

There are no additional requirements for luminaires that have RG0 or RG1 (based on 200 mm, 0.011 radians) sources according to IEC/TR 62778, or lamps that are evaluated as RG0 or RG1 under the same conditions.

3. Having RG1/RG2 (Ethr) boundary conditions

For luminaires with RG1/RG2 (Ethr) boundary conditions in accordance with IEC/TR 62778, the following requirements shall be met:

a) For fixed luminaires, an additional evaluation shall be carried out in accordance with IEC/TR 62778 with the aim of finding the distance Xm of the luminaire from the boundary of RG2 and RG1 and marking it as required by this standard.

b) For portable and hand-held luminaires exceeding 200 mm (measured in 0.011 radians), markings are required to be marked in accordance with IEC 60598-1.

The standard also prompts:

- Usually the classification of the risk group should be available from the LED light source manufacturer;