This guide covers split load vs dual RCD vs RCBO board configurations, circuit arrangement and allocation, BS 7671 labelling requirements, type testing under BS EN 61439, SPD installation, wiring best practice, and the common mistakes found during EICR inspections. Wiring a Distribution Board is vital in any electrical installation. The Main feeder cable to the Distribution Board should be able to handle the total power anticipated when all the sub circuits in the Distribution Board. A consumer unit (CU) also known as panel box, breaker box or fuse box is a type of a distribution board (aka electric panel, breaker panel, panelboard or main breaker-box or main service panel) which is used to distribute and fed the electric power to the sub-circuits and final sub-circuits. Electrical wiring in the United Kingdom refers to the practices and standards utilised in constructing electrical installations within domestic, commercial, industrial, and other structures and locations (such as marinas or caravan parks ), within the region of the United Kingdom. It serves as a central hub for distributing electricity throughout a building, ensuring that power is delivered safely and efficiently to all the required locations.