Changes to the thickness requirements for electrical distribution boxes

Minimum thickness requirements for electrical distribution boxes vary by type, material, and size, with recent standards emphasizing safety, load capacity, and structural integrity.

• Low-voltage distribution boxes: The wall thickness should not be less than 1.5mm, while metal auxiliary poles should be at least 1.2mm. These values comply with national standards and ensure safety and earthquake resistance .
• Power distribution cabinets: The cabinet body is generally made of cold-rolled steel with a minimum thickness of 2.0mm, doors and panels at 2.0mm, and back panels at 3.0mm to withstand mechanical and electrodynamic stresses .
• Mounting strips and internal components: CRCA MS strips for mounting internal components are typically 2mm thick, and earth clamps are also 2mm thick .

1. Type and Purpose of the Box:

   • Lighting distribution boxes: Smaller loads allow for 1.5–2.0mm thickness depending on size. Boxes ≥600mm can use 2.0mm cold-rolled steel, while smaller boxes may use 1.5mm .
   • Power distribution boxes: Require ≥1.5mm, with larger or high-capacity boxes often using 2.0mm or more to handle higher currents and mechanical stress .
   • Power distribution cabinets: Typically ≥2.0mm to ensure structural integrity and protection during faults or long-term operation .

2. Size and Weight: Larger boxes require thicker steel to prevent deformation:

   • Width 500–800mm: minimum 1.2mm
   • Width ≥800mm: minimum 1.5mm
   • Semi-perimeter ≥900mm: minimum 1.5mm;