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. Check electrical parameters: First understand the basic electrical parameters of Distribution box so that you can have a general understanding of the capacity and performance of the distribution box. 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. A distribution board or distribution box is where the main power supply is distributed to multiple loads. And all the switching and protective devices are installed in the distribution box. Single Phase Distribution Box generally consists of Double Pole MCBs, Single Pole MCBs, and RCCBs. In this guide we'll cover three things.