As for the equipment inside, there are certain differences: the first level distribution cabinet generally has isolation switches, circuit breakers, leakage protectors, etc. (3) Power distribution from tertiary switch boxes to electrical equipment must follow the “one machine, one switch” principle, with no branching allowed. According to the hierarchical. The three-level distribution system refers to a system that distributes electric power through three levels of distribution devices from the incoming power line at the construction site to the electrical equipment. It is a vital part and central hub of any electrical system. The hub distributes electrical power from a single input source to various circuits throughout a building.
