Definition of explosion-proof equipment: Electrical equipment that will not cause ignition in the surrounding explosive environment under specified conditions.

All explosion-proof products have an explosion-proof level, which can indicate the explosion-proof form and applicable occasions of the product. For example, Exd II BT4 is an explosion-proof grade, and the specific meaning of it is introduced below.

Ex: Explosion proof sign

d: The explosion-proof form is explosion-proof. There are also intrinsic safety types IA and IB; Increased safety type e; Oil filled type o; Sand filled mold q; Pouring and sealing type m; Composite type (such as explosion-proof distribution boxes, which often use de combination).

II: Refers to Class II explosion-proof electrical equipment. This type of explosion-proof electrical appliance is suitable for explosive gas environments other than coal mines. (Coal mines are Class I). There is also Class III: electrical equipment in explosive dust environments other than coal mines. Class IIIA: combustible flying flocs; Class IIIB: Non conductive dust; Class IIIC: Conductive dust.

B: Class IIB gas. There are also IIC and IIA levels. IIC level is the highest level and can be applied to IIA and IIB. IIB level can be applied to IIA level. But low-level ones cannot be applied to high-level ones.

T4: The temperature group is T4, and the maximum surface temperature of the equipment is less than 135 ℃.