Home distribution boxes typically handle single-phase power supplies and contain 6 to 24 circuits. They include standard circuit breakers for lighting, outlets, and major appliances like water heaters and air conditioning units. However, the key to. 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. It receives power from the main electrical supply and divides it into separate circuits, each. Your circuit count leads directly to the box size. Most homes need: Future-Proofing: Add 20% extra circuit spaces upfront. Future solar panels or EV chargers won't require expensive upgrades.