All explosion-proof products have an explosion-proof level. Based on the explosion-proof level, the explosion-proof type and applicable occasions of the product can be distinguished. For example, the explosion-proof level Exd IIB T4 is described in detail below.

Ex:Explosion-proof Marking。

d: The explosion-proof type is flameproof.。There are also intrinsically safe types ia, ib; increased safety type e; oil-immersed type o; sand-filled type q; encapsulated type m; composite types (such as those commonly used in explosion-proof distribution boxes).。

Ⅱ: Refers to the second category of explosion-proof electrical equipment.。This explosion-proof electrical appliance is suitable for other explosive gas atmospheres except coal mines.。（Coal Minebelong toⅠVarious）。There is also Category Ⅲ: electrical equipment for explosive dust atmospheres other than coal mines.。Class ⅢA: combustible flyings; Class ⅢB: non-conductive dust; Class ⅢC: conductive dust.。

B:ⅡBLevelGas。alsoWithⅡC And ⅡA。Class ⅡC is the highest level and can be used for ⅡA and ⅡB.。Class ⅡB is suitable for Class ⅡA, but lower levels cannot use higher levels.。

T4: The temperature class is T4, and the maximum surface temperature of the equipment is below 135°C.。

The above is an introduction to what the explosion-proof level Exd ⅡB T4 means. For more related information, please visit Hualong Explosion-proof at www.hlfbdq.com.。