A typical 12-position distribution box measures approximately 255 x 200 x 110 mm (10 x 7.9 x 4.3 inches).

Standard Dimensions

For most 12-way DIN rail distribution boxes, the common dimensions are:

• Length (L): 250–255 mm
• Width (W): 190–200 mm
• Height (H): 85–110 mm For example, the Marshal MDB-12F metal distribution box has dimensions of 250 x 190 x 85 mm with an IP40 rating, while a plastic IP65-rated box measures 255 x 200 x 110 mm, suitable for indoor and outdoor use .

Material and Mounting Considerations

• Plastic enclosures (ABS or polycarbonate) are often used for IP65/IP66 waterproof ratings, providing protection against dust and water, ideal for outdoor installations .
• Metal enclosures provide higher mechanical strength but typically have lower IP ratings (e.g., IP40) and are used in indoor or controlled environments .
• Mounting options include surface mount or flush mount, depending on installation requirements .

Additional Notes

When selecting a 12-position distribution box, consider not only the external dimensions but also:

• Internal layout for MCBs, RCDs, busbars, and neutral/earth bars
• Cable entry space and wiring room
• Future expansion possibilities
• Compliance with local electrical standards (IEC, UL, BS) These factors ensure the box fits the intended application safely and efficiently .