An electrical sub panel, also known as a sub distribution board or sub circuit breaker panel, is a smaller secondary panel connected to the main electrical panel in a building. It serves as an extension of the main electrical panel to distribute power to different areas or circuits. From the transformer's low-voltage side (0. 4kV), power is distributed to a main distribution panel (primary distribution box). From there, it is routed to individual building distribution boxes (secondary distribution boxes), which subsequently supply power to unit-level distribution boxes. Primary distribution systems consist of feeders that deliver power from distribution substations to distribution transformers. Its purpose is to take a single, large circuit from the main panel and divide that capacity into multiple, smaller circuits closer to where the. This article covers the electrical system in buildings (including distribution) at a very basic level. It ensures that electricity flows.
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