To choose a home distribution box, you must count your circuits and add 30% spare space. A distribution box, sometimes referred to as a panel board, distribution board, or breaker panel, is an essential part of electrical systems that makes it easier to distribute electricity throughout a structure. Dividing incoming electrical power from the main supply into subsidiary circuits is the. In this guide, I'll walk you through a practical, step-by-step process to size your distribution box based on actual load current.