1. Internal Arrangement: Electrical components and wiring within the box must be neatly organized, clearly labeled, and aesthetically arranged for ease of maintenance. The interior should be free from dust and debris. All wires must have intact insulation without any damage.
2. Wire Specifications: The cross-sectional area of the wires should meet standard requirements, capable of handling the normal working current with some margin.
3. Wire Protection: Wires should not be exposed to the air directly. For example, when connecting an explosion-proof pressurized enclosure to an audio-visual alarm line, an explosion-proof flexible conduit must be used.
4. Cable Sealing: Inlet and outlet cables must pass through rubber sealing rings, tightened with washers and compression nuts to ensure the integrity of the explosion-proof enclosure’s seal. Cables should not be loose.
5. Component Placement in Pressurized Enclosures: Internal electrical components, such as frequency converters, should be placed close to the air inlet and away from the air outlet.
6. Grounding of Metal Cabinets: Metal explosion-proof distribution boxes must be reliably grounded, with the grounding wire connected to the cabinet’s outer shell. For three-phase systems without a neutral wire, the grounding wire should have a cross-sectional area of at least 4mm². In a three-phase three-wire system, the ground cross-section should also be at least 4mm².
7. Wiring Adherence: Wiring must strictly follow the schematic diagrams. Wires should be properly labeled to ensure secure connections at terminals.
