Requirements for the distance of the secondary distribution box from the ground

The recommended height for a secondary distribution box from the ground is approximately 1.3 to 1.5 meters, with 1.5 meters being commonly used for construction and industrial applications.

Recommended Installation Height

For secondary distribution boxes, the bottom of the enclosure should generally be installed between 1.3 meters and 1.5 meters above the ground. This height ensures that operators can comfortably perform routine maintenance, operate switches, inspect circuits, and read instruments without strain . In construction site applications, a standard height of 1.5 meters from the ground is widely adopted to meet ergonomic and safety requirements .

Additional Placement Considerations

• Accessibility: The box should be installed in a location that is easily reachable for maintenance personnel, with sufficient space around it to allow safe operation and emergency handling .
• Proximity to Equipment: The horizontal distance between the secondary distribution box and the electrical equipment it serves should not exceed 30 meters, and the distance between the box and any switchboxes should not exceed 3 meters to reduce line losses and improve efficiency .
• Environment: Install the box in a dry, well-ventilated, and safe location, avoiding areas with corrosive gases, strong vibrations, liquid splashes, or heat sources .
• Grounding: Proper grounding and bonding are essential for safety, ensuring that fault currents are safely directed to the earth and preventing potential hazards from energized metal parts .

Summary

To summarize, the secondary distribution box should be mounted with its bottom surface approximately 1.3–1.5 meters above the ground, ideally at 1.5 meters for standard applications. Ensure it is accessible, properly grounded, and positioned close enough to the equipment it serves to maintain efficiency and safety .