Explosion Proof LED Lights Temperature Stability, High Luminous Efficiency

Explosion Proof LED Lights due to temperature stability, high luminous efficiency, green and other advantages, in recent years has been widely used in the field of explosion-proof, used to replace the traditional gas discharge lamp, which is the future trend of the lighting industry. But because of its high brightness, radiation energy, light radiation caused by the possibility of ignition also increased, so the concept of LED explosion-proof light radiation is also proposed.

First, the optical radiation requirements:

       The optical radiation standard IEC60079-28 was released in 2006 by the IEC TC31 and was upgraded in 2015. At present, ATEX and IECEx certification for some LED lamps of light radiation is mandatory, but the domestic explosion-proof certification has not yet requested, the national standard is being prepared.

Second, the principle of light radiation lit:

1, the optical radiation is absorbed by the surface of the object or particles, so that the temperature increases under certain conditions will be the surface of the radiation or the temperature of the particles rise enough to ignite the extent of the surrounding explosive environment.

2, when the wavelength of radiation and combustible gas absorption band matching, can make a certain volume of flammable gas heat ignition.

3, when there is a strong ultraviolet radiation, the ultraviolet light can make oxygen molecules photolysis, the formation of photochemical ignition.

4, high-energy direct laser will lead to gas or steam decomposition,Explosion Proof LED Lights  resulting in shock waves and plasma, the two form the ignition source.

Third, the optical radiation protection:

Light radiation causes three elements of the explosion: radiation sources, radiation absorbers and explosive hazardous environments. There are three ways to protect the radiation source:

1, op is: intrinsically safe optical radiation: by limiting the radiation intensity of light to prevent ignition, this protection can be in the 0 area, 1 area, 2 areas used.

2, op pr: protective light radiation: the optical radiation is limited to the optical fiber or other transmission medium, so that optical radiation can not be leaked to an explosive hazardous environment. The specific method of protection is through a reinforced fiber optic cable, conduit or pipe,Explosion Proof LED Lights  or may cause the optical radiation spill to be protected by other type of explosion protection. This protection can be used in Zone 1.

3, op sh: optical system with interlock device. When the optical radiation leaks, by using a special function set, so that the light radiation system to cut off the light source time is less than the explosion delay time, that is, before the explosion cut off the light source.

Note: Explosion-proof LED fixtures are only available for op is protected.

Four, op is the request

op is more sensitive to the frequency of light radiation, continuous wave radiation and pulsating radiation is not the same, and their respective qualified criteria are also different.

Fifth, Explosion Proof LED Lights design

1, limit power mode:

According to IEC 60079-28, if the radiation radiation system radiation surface area greater than 400mm ², optional optical power value, irradiance value or radiation surface temperature limit of any one to determine.

Design points: limit the irradiance of the radiation surface of the light source or the surface temperature of the radiation surface of the light source. As far as possible not to concentrate, to astigmatism, LED panel as large as possible, to avoid the use of condenser concave reflector.

Light radiation intensity limit:

Optimize the LED driver circuit design: the drive back-end set over-current protection circuit to ensure that the drive circuit in any state flows through the LED array current does not exceed the limit.

Application LED inherent safety features (need to determine the test): the current flowing through the LED is too large, will cause LED luminous flux attenuation, and even LED lighting power rise to a certain extent will lead to LED failure and automatically extinguished.