Dimensions of a two-circuit distribution box

A 2-circuit distribution box is compact, typically designed to house two protective devices, with a footprint small enough for wall mounting in garages, small outbuildings, or as a sub-board.

Typical Dimensions

A 2-circuit (2-way) distribution board is the most basic configuration of a consumer unit. While exact dimensions vary by manufacturer, these boxes are generally hand-sized units with a compact footprint to save space in low-demand applications . Common external dimensions for small wall-mounted enclosures range from approximately 200 × 200 × 120 mm (height × width × depth) up to slightly larger sizes depending on the brand and IP rating . The internal space is sufficient to accommodate two circuit breakers or fuses, along with wiring clearance.

Applications

2-way distribution boxes are often used for:

• Small outbuildings or garages
• Dedicated high-power circuits (e.g., immersion heaters or cookers) alongside a general lighting circuit
• Sub-main boards feeding another distribution board in a larger installation

Installation Considerations

• Depth: Ensure the box is deep enough to allow proper wire bending and splicing; typical depths range from 120 mm to 150 mm for small units .
• Mounting: Wall-mounted units are most common, with surface or flush mounting options.
• Future expansion: While a 2-way board is compact, consider whether additional circuits may be needed to avoid overcrowding.

Summary

A 2-circuit distribution box is small, compact, and designed for low-demand applications, typically measuring around 200 × 200 × 120 mm externally, with enough internal space for two breakers and wiring. Its compact size makes it ideal for garages, small annexes, or as a sub-board, while still providing safe and efficient electrical distribution .