99热这里只有精品6_无码精油按摩潮喷在_天天摸天天碰天天添_美女扒开内裤无遮挡18禁免费观看【_蛮好的人生在线观看免费高清_公媳谢莹李瑞峰免费阅读_在线+国产+无码_无码国产精品一区二区免费l_国产成人精品三级在线观看

The standards for explosion-proof certification in our country are synchronized with IEC certification. The officially approved explosion-proof certification by the state is divided into eight different forms, namely explosion-proof certification (d), increased safety explosion-proof certification (e), intrinsic safety explosion-proof certification (intrinsic safety explosion-proof certification) (i), positive pressure explosion-proof certification (p), oil filled explosion-proof certification (o), sand filled explosion-proof certification (q), spark free explosion-proof certification (n), and sealed explosion-proof certification (m). In addition, there are two types of explosion-proof certifications: explosion-proof special type and dust explosion-proof type. Below, Shenzhen Zhongnuo Testing Technology Co., Ltd. brings an interpretation of the current national explosion-proof standards and certification types as of 2018.

In automation instrumentation equipment, the explosion-proof certification widely used by countries around the world is the first three types, namely explosion-proof type (d), increased safety type (e), and intrinsic safety type (i).

1. Explosion proof certification for explosion-proof electrical equipment (d)

Explosion proof certification for electrical equipment with explosion-proof enclosures refers to electrical equipment that encloses components capable of igniting explosive mixtures within an enclosure that can withstand the explosive pressure of the internal explosive mixture and prevent the transmission of explosive mixtures to surrounding areas.
2. Explosion proof certification for increased safety electrical equipment (e)

Under normal operating conditions, electrical equipment that does not generate sparks or dangerous temperatures that ignite explosive mixtures and takes measures to improve its safety level structurally to avoid ignition under normal and specified overload conditions can obtain explosion-proof certification for increased safety electrical equipment.
3. Explosion proof certification for intrinsically safe electrical equipment (i)

Electrical equipment that cannot ignite explosive mixtures due to sparks or thermal effects generated under normal operation or standard test conditions. The explosion-proof certification of intrinsically safe electrical equipment and its associated equipment is divided into two levels, IA and IB, according to the location and safety level of the intrinsically safe circuit.
IA level explosion-proof certification: Electrical equipment that cannot ignite explosive gas mixtures during normal operation, one fault, and two faults.
IB level explosion-proof certification: Electrical equipment that cannot ignite explosive gas mixtures during normal operation and in the event of a malfunction.

As of 2018, the current national explosion-proof standards