Popularization of explosion-proof knowledge

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Definition of explosion-proof equipment: Electrical equipment that will not cause ignition in the surrounding explosive environment under specified conditions. Explosion-proof products all have an explosion-proof rating, from which the explosion isolation type and applicable environments of the product can be determined. For example, the explosion protection rating Exd II BT4 – below is an explanation of its specific meaning. Ex: Explosion protection mark d: The explosion protection type is flameproof. There are also intrinsically safe types ia, ib ； Increased safety type e ； Oil-filled type o ； Sand-filled type q ； Encapsulated type m ； Composite type (for example, explosion-proof distribution boxes often use the DE combination). II: Refers to Class II explosion-proof electrical equipment. This type of explosion-proof electrical equipment is suitable for explosive gas environments other than coal mines. (Coal mines are Category I). There is also Category III: electrical equipment for explosive dust environments other than coal mines. Class IIIA: Flammable fluff ； Category IIIB: Non-conductive dust ； Class IIIC: Conductive dust. B: Class IIB gas. There are also IIC grade and IIA grade. Class IIC is the highest class and can be applied to both Class IIA and IIB. Class IIB can be applied to Class IIA. However, the lower level cannot be applied to the higher level. T4: The temperature category is T4, with the maximum surface temperature of the equipment being less than 135°C. Based on the minimum spark energy capable of triggering an explosion, the International Electrotechnical Commission (IEC) standards adopted by China, Europe, and most countries and regions worldwide classify explosive gases into four hazard levels. Users can determine which flammable and explosive gases may be generated during the production process in their own factories, and then refer to the diagram below to select appropriate explosion-proof electrical equipment.