A distribution box is a low-voltage electrical enclosure that receives incoming power and distributes it safely to multiple outgoing circuits through protective and switching devices such as MCBs, RCDs, RCBOs, fuses, isolators, busbars, neutral bars, earth bars, and surge. A distribution box is a low-voltage electrical enclosure that receives incoming power and distributes it safely to multiple outgoing circuits through protective and switching devices such as MCBs, RCDs, RCBOs, fuses, isolators, busbars, neutral bars, earth bars, and surge. Every wire in your home — every socket, every light, every appliance circuit — traces back to a single grey box on the wall: the distribution board, also called a consumer unit or, in older installations, a fuse box. It is the most critical component in any electrical installation, and. A distribution box, also known as a distribution panel or board, is a cabinet that holds electrical parts used to supply power to multiple circuits within a system. The. The Distribution box system diagram mainly includes the following parts: Incoming line part: Displays the incoming line source of the distribution box, which may be a single-line incoming line or multiple-line incoming lines (such as normal power supply and backup power supply), and marks the. How is a distribution board (consumer unit) wired in the UK? The incoming supply enters a double-pole main switch, then feeds the protective devices — MCBs, RCBOs or RCDs — that protect each final circuit. A surge protective device (SPD) sits on the supply side where a risk assessment requires it.