Explosion-proof lamps use more types and security lights are similar but different

Explosion-proof lamps are used in hazardous locations where flammable gases and dust are present. They can prevent arcs, sparks, and high temperatures inside the lamp from igniting flammable gas and dust in the surrounding environment, thereby reaching the explosion-proof requirements. Also known as explosion-proof lighting, explosion-proof lighting. The appearance of general safety lamps and explosion-proof lamps is very similar. The main difference between the two is that the explosion-proof lamps have obvious certification numbers for explosion-proof electrical appliances. The explosion-proof signs are cast on the lamp housing, while general safety lights do not have these features and signs.

For the selection of explosion-proof lights, the classification is generally based on the selected light source, explosion-proof structure type, and use mode. According to the light source classification, there are explosion-proof incandescent lamp, explosion-proof high-pressure mercury lamp, explosion-proof low-voltage fluorescent lamp, mixed light source lamp, etc.; according to the explosion-proof structure type, there are explosion-proof lamps, increased safety lamps, composite lamps, etc.; Explosion-proof lamps and portable explosion-proof lamps.

1, according to explosion-proof type

According to the explosion-proof type, it can be divided into 5 types: flameproof, increased safety, positive pressure, non-sparking and dust explosion-proof. It can also be combined by other explosion-proof types and the above-mentioned various explosion-proof types or composite type and special type. .
 

2, according to the type of protection against electric shock

According to the type of protection against electric shock can be divided into I, II, III category. The protection against electric shock is to prevent the explosion-proof lamp housing from being easily touched and the parts are electrified, so that the human body is exposed to electric shock or conductors with different potentials to generate electric sparks and ignite the explosive mixture.

AI class—On the basis of basic insulation, accessible conductive parts that are not energized during normal operation are connected to the protective ground conductor in the fixed line.

Class BII - Use double insulation or reinforced insulation as a safety measure without grounding protection.

Class CIII - Use a safe voltage with an effective value of not more than 50V, and no voltage above it will be generated.

Category D0 - only rely on basic insulation as a safety protection measure.

Most of the explosion-proof lamps and lanterns are protected against electric shock, and only a few are Class II and III lamps. For example: all plastic explosion-proof lamps, explosion-proof flashlight Jane.

â–¡ Type Symbol Explosion Protection Principle

Flameproof type

The components of the device that may ignite the explosive gas mixture are all enclosed within a housing that is capable of withstanding any interface or structural gap through the housing. The flammable mixture that has penetrated into the interior of the device explodes without damage and ensures internal The flame gas reduces energy when propagating through the gap and is not enough to detonate the shell gas.

Zeng Anxing

Electrical equipment that does not produce arcs or sparks under normal operating conditions will take additional measures to increase its safety and prevent explosions of the possibility of dangerous temperatures, arcs and sparks in its internal and external components. Protection measures to improve equipment reliability and safety performance.

Positive pressure type

By keeping the pressure of the protective gas inside the device enclosure higher than the surrounding explosion-proof ambient pressure to a safe electrical device, a static positive pressure is maintained inside the system or a continuous flow of air or inert gas is maintained to restrict entry of the flammable mixture into the interior of the enclosure. The flammable gas that enters the enclosure when the device is in a non-positive pressure state is taken away to prevent the formation of a flammable mixture in the enclosure.

This placement

All circuits inside the equipment are intrinsically safe circuits of the explosion-proof gas atmosphere that are not specified by any spark or any effect produced under standard conditions (including normal operation and specified fault conditions).

Sealing type

Explosive sparks, arcs, or dangerous temperature electrical components that may ignite the explosive mixture will be encapsulated in the encapsulant (composite) so that it cannot ignite the surrounding explosive mixture. Enclosure measures are used to prevent electrical components. Short-circuiting, solidification of electrical insulation prevents sparks on the circuit and the ignition of arcs and hazardous temperatures, prevents intrusion of explosive mixtures, and controls surface temperatures under normal and fault conditions.

Oil type

The entire equipment or components of the equipment are invaded in the oil I protection fluid l so that it cannot ignite the explosion-proof gas environment above the oil surface or outside the housing.

Sand filling type

The shell is filled with sand or other powder material of specified characteristics so that, under the specified conditions of use, arcs or high temperatures generated in the shell cannot ignite the type of electrical equipment protection of the surrounding explosive gas atmosphere.

Airtight Type h This type of explosion-proof equipment uses a hermetic enclosure. That is, the explosive gas mixture in the environment cannot invade the inside of the device housing. The airtight enclosure is sealed by melting, squeezing or gluing. This enclosure is mostly non-detachable to ensure permanent tightness.

3, according to the protection level of the shell

Classified according to the protection class of the enclosure: In order to protect the dust, solid foreign matter and water from entering the lamp cavity and touching or accumulating on the live parts to cause flashover, short circuit or damage to the electrical insulation, etc., there are a variety of enclosure protection methods to protect the electrical Insulation effect. The characteristic letter "IP" followed by two digits is used to characterize its enclosure protection level. The first number indicates the protection against humans, solid objects or dust. Divided into 0-6 levels. Explosion-proof lamps are sealed lamps. Their dust-proof capacity is at least 4 levels. The second number indicates the protection against water and is classified into 0-8.

4, according to the lamp design support surface material

According to the lighting design of the support surface material classification: Indoor explosion-proof lighting may be installed on many common surfaces of combustible materials, such as wooden walls and ceilings, which do not allow explosion-proof lighting installation surface temperature exceeds the safety value. According to whether explosion-proof lamps can be installed directly on the surface of ordinary combustible materials, they can be classified into two categories.