Verify the specifications of the power distribution box against project requirements. Ensure all components are present and undamaged. Analyze the incoming line part: Determine the incoming line source of the distribution box and. What size distribution box do you need for a house? How do you know which circuit breaker to use? Can you add more breakers later? Why do you need GFCI or AFCI breakers? Choosing the right size and setup for your distribution box keeps your electrical system safe and working well. You lower the. Hey, in this article we are going to see the Single Phase Distribution Box Wiring Diagram and Connection Procedure. This guide shows you how to organize circuit breaker wiring properly.