The composite explosion-proof certification mark indicates that a single explosion-proof type of the product cannot achieve explosion-proof, and two or more explosion-proof types must be used

For example, explosion-proof equipment with an antenna, the antenna part is generally treated with intrinsic safety, and this equipment is both explosion-proof and intrinsic safety,

In addition, the nozzle of the fuel gun generally belongs to Zone 0 and can only be used for cost control. The other parts can be made into Zone 1, which can be made into intrinsic safety IB or explosion-proof type.

Composite explosion-proof products do not necessarily have to meet all the requirements of different explosion-proof types, nor do they necessarily have a higher explosion-proof rating than a single explosion-proof type.

The explosion-proof level of a product mainly depends on the gas/dust combination, temperature group, and equipment protection level

Gas combination: IIC>IIB>IIA

Dust combination: ⅢC＞ ⅢB＞ ⅢA

Temperature group: T6＞T5＞T4＞T3＞T2＞T1

Equipment protection combination: Ga＞Gb＞Gc，Da＞Db＞Dc

For more details, please contact Shenzhen Zhongnuo Testing Technology Co., Ltdfurthercommunication!