Both busbars are connected to the main breaker via incoming power supply (power entrance conductors). They are typically arranged as two hot busbars in a 120/240V single-phase panel for 1-pole or 2-pole breaker connections. In electric power distribution, a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution, transmission, or switching substations. Consequently, power busing design needs critical consideration in terms of performance under converter operation, asymmetric loading, short-circuits, thermal and insulation breakdown. Ensuring this intricate system's efficiency lies in the details, and one such detail is the proper connection of bus bars in power systems. Think of it like a highway for electricity: power flows into the bus from a source, then branches out to wherever it's needed.
[PDF Version]