Shenzhen ZhongNuo Inspection Technology Co., Ltd. is based in South China, offering on-site explosion-proof construction, safety inspections, renovations, project acceptance, and explosion-proof installation consulting services. We are well-versed in explosion-proof construction standards, boast a team of experienced constructors, and have served major enterprises such as PetroChina, LG, Huanlan Environment, BOE, and Sinovac Biotech, receiving consistent praise and trust from our clients!
As the global energy and chemical industry expands, construction in explosive hazardous environments becomes increasingly widespread, and the prevention and inspection of explosive environments become increasingly crucial.
Especially in flammable dust environments such as plastic factories, feed/food/cereal processing plants, metal polishing workshops, and papermaking/forestry wood flour/fiber dust factories, the number of projects involving explosion-proof installation, design, and renovations is also on the rise.
Whether it's large-area explosion-proofing or local explosion-proofing, if there are hidden dangers in product quality or the quality of installation and modification.
Our personnel and property safety are at significant risk, so we must maintain strict quality control at every stage to ensure the reliability and safety of explosion-proof installations and renovations.
Shenzhen Zhongnuo Inspection Technology Co., Ltd. offers explosion-proof construction and modification consultation services, boasting a wealth of qualifications and case studies. It's definitely worth it!

Equipment protection grounding in explosive environments shall comply with the following regulations (Shared by Shenzhen ZhongNuo Inspection & Testing Technology Co., Ltd.)
In accordance with the relevant provisions of the current standard "Code for Design of Grounding for Electrical Installations" GB/T50065, the following parts that do not require grounding should still be grounded in explosive environments:
1) Non-electrically conductive ground: metal enclosures of equipment with an alternating current rated voltage of less than 1000V and a direct current rated voltage of less than 1500V, which are normally not energized.
2) In dry environments, equipment with alternating voltage not exceeding 127V and direct voltage not exceeding 110V typically has metal casings that are not charged.
3) Equipment installed on a grounded metal structure.
(2) In explosive hazardous areas, the exposed, conductive parts of the equipment should be reliably grounded. All equipment within explosive areas 1, 20, and 21, as well as other equipment within explosive areas 2 and 22, excluding lighting fixtures, should use dedicated grounding wires. If the grounding wire is installed in the same protective conduit as the phase wire, it should have insulation equal to that of the phase wire. Lighting fixtures within explosive areas 2 and 22 can use a metal piping system with a reliable electrical connection as a grounding wire, but not the pipeline for conveying substances.
(3) In different directions of the slope in the explosion hazard area, the grounding main should be connected to the grounding body at least twice.

Basic Requirements for Explosion-Proof Electrical Installations in Explosive Environments (Shared by Shenzhen Zhongnuo Inspection & Technology Co., Ltd.)
1. Oil-immersed equipment should be used under conditions of no vibration, no tilt, and fixed installation.
2. When using non-explosion-proof equipment for mechanical transmission as partition walls, the following regulations should be observed:
(1) Rooms housing electrical equipment should be separated from explosive hazard areas by solid walls made of non-combustible materials.
(2) Transmission shafts passing through walls should be sealed with gland packing or an equivalent sealing method.
(3) The exit of the electrical equipment room should lead to an environment free of explosive hazard areas.
(4) When the room housing the equipment must be connected to an explosive atmosphere, the explosive atmosphere should be maintained at a positive pressure relative to the room.
3. Electrical wiring and equipment in explosive environments, excluding inherently safe circuits, should be equipped with overcurrent, short-circuit, and grounding protection. Overcurrent protection is not required for electrical equipment that cannot experience overloading. Motors in explosive environments, in addition to the necessary protection as required by current standards, should also be equipped with phase failure protection. If the automatic shutdown of electrical equipment could pose a greater danger than the ignition hazard, an alarm device should be used instead of the automatic shutdown device.
4. In emergency situations, appropriate measures should be taken at a suitable location outside the hazardous area to disconnect the power to the equipment in the hazardous area. Continuous operating equipment should not be included in the emergency shutdown circuit and should be installed on a separate circuit to prevent the occurrence of additional hazards.
5. The design of substation, distribution substation, and control room shall comply with the following regulations:
Transformer substations, distribution stations (including distribution rooms, etc.), and control rooms should be located outside of explosive atmosphere environments. When they are in a positive pressure room, they can be arranged in Zone 1 or Zone 2.
(2) For explosive gas atmospheres where the gas is heavier than air, the equipment floor of electrical and instrumentation in power substations, distribution stations, and control rooms located in the additional 2 zone of the explosion hazard area should be elevated 0.6 meters above the external ground level.

Basic Knowledge and Requirements for防爆 Cable Use at Construction Sites (Shared by Shenzhen ZhongNuo Inspection & Testing Technology Co., Ltd.)
Installation methods for electrical wiring in explosive gas environments can be categorized into cable wiring and conduit wiring methods.
Note: The installation of inherently safe circuits does not have to comply with the provisions of this article.
7.1 General Provisions
7.2 Electrical wiring should be installed in areas with lower explosion hazards or at a greater distance from the source of release, avoiding locations prone to mechanical damage, vibration, corrosion, dust accumulation, and those with hazardous temperatures. When avoidance is not possible, preventive measures should be taken.
7.3 The selected low-voltage cables or insulated conductors must have a rated voltage higher than the working voltage of the line and not less than 500V. Insulated conductors must be installed within conduits.
7.4 It is strictly prohibited to cross explosive gas environments with overhead lines of 10kV and below; the horizontal distance between the overhead line and the explosive gas environment should not be less than 1.1 times the height of the pole tower.
7.5 Cables and accessories shall be installed in such a position as to prevent them from being damaged by external mechanical forces, corrosion, or chemical influences (such as solvent effects), as well as from the effects of high temperatures (also see 6.1.2.4.4 regarding this safety circuit). If such conditions cannot be avoided, protective measures shall be taken during installation, such as using conduits or selecting the cable type (armored cables, shielded wires, seamless aluminum sheathed cables, mineral insulated metal sheathed cables, or semi-rigid sheathed cables, etc., to minimize damage).
7.6 Solid-core wire without a jacket should not be used for conductive wiring unless installed within a distribution board, housing, or conduit system.
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