This guide shows you how to organize circuit breaker wiring properly. You will learn to build a safe, efficient, and professional electrical system today. Circuit breaker wiring configurations involve organizing main switches, busbars, and branch breakers within a distribution box. 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 distribution board or distribution box is where the main power supply is distributed to multiple loads. Single Phase Distribution Box generally consists of Double Pole MCBs, Single Pole MCBs, and RCCBs. It includes isolator, RCCB (Residual current circuit breaker) or RCD (Residual-current device) devices, protective fuses or MCB's (Miniature Circuit Breaker). 3 phase DB box wiring is an essential component of electrical installations in commercial and industrial buildings.