Handles three-phase power and typically connects to secondary loads such as motors or machinery. Equipped with larger three-phase circuit breakers. The final connection point for end-use devices, delivering 220V (single-phase) power. Many feeders leave substation in a concrete ducts and are routed to a nearby pole. The following electrical ratings are typical: As a result of locating power transformers and their close-coupled. Primary distribution transmits high-voltage power to substations, while secondary distribution delivers low-voltage electricity to end-users like homes and businesses. In other words, secondary distribution is the portion of the grid that carries power from distribution transformers typically mounted on poles or in. From there, it is routed to individual building distribution boxes (secondary distribution boxes), which subsequently supply power to unit-level distribution boxes (tertiary distribution boxes), and finally to household systems.
[PDF Version]