Requirements for the spacing between double layers of distribution boxes

For double-layer distribution boxes, a minimum spacing of 1 meter is recommended for voltages up to 600V, with increased spacing for higher voltages and adequate clearance for maintenance and safety.General Spacing Guidelines

Distribution boxes should be spaced to allow safe access, maintenance, and fire prevention. For boxes servicing voltages up to 600V, a minimum of 1 meter between enclosures is recommended. This distance ensures that technicians can open doors simultaneously and move safely around the boxes without obstruction. For voltages above 600V, spacing should increase proportionally, with boxes above 75kV requiring at least 4 meters of clearance on all sides .

Double-Layer Considerations

When arranging double-layer distribution boxes, consider both vertical and horizontal spacing:

• Vertical spacing should allow for safe access to the upper layer without obstruction from the lower layer.
• Horizontal spacing between adjacent boxes should maintain at least 1 meter for low-voltage systems, and more for higher voltages or when cable routing requires additional room .
• Ensure airflow and heat dissipation by leaving sufficient gaps around each box, especially in high-current installations .

Access and Maintenance

• Technicians should be able to stand and work comfortably in front of each box.
• Clearance in front of panels should follow NEC guidelines: 36–48 inches depending on what is opposite the panel, with at least 78 inches vertical clearance for safe operation .
• Double-layer setups should allow simultaneous servicing of both layers without interference.

Additional Safety Measures

• Use metal partitions or dividers if boxes are close to prevent interference or accidental contact.
• Maintain proper grounding and insulation for all boxes.
• Follow IEC 61439 or local standards for spacing, temperature rise, and modular expansion allowances . In summary, for double-layer distribution boxes, maintain at least 1 meter horizontal spacing for low-voltage systems, increase spacing for higher voltages, ensure vertical clearance for upper layers, and provide sufficient room for safe access, maintenance, and heat dissipation.