Expanding a distribution board involves adding extra circuits, the main switch, circuit breakers, and earth leakage circuit breakers. Consider connecting a Perilex socket for the induction hob, or connecting a washing machine separately. There are regulations to follow: sufficient capacity, correct. MCB distribution board extension boxes are designed to provide additional space for accommodating more circuit breakers or wiring within your existing consumer unit setup. You leave space for safety devices like. A second breaker box, more commonly referred to as a subpanel, functions as a power distribution point downstream from your main electrical service panel. It performs several central functions: Firstly, it.