2) Secondary power distribution equipment is a general term for power distribution cabinet and motor control center. The power distribution cabinet is used in occasions with scattered load and few circuits; Motor control center is used for occasions with concentrated load and. Primary distribution systems consist of feeders that deliver power from distribution substations to distribution transformers. A feeder usually begins with a feeder breaker at the distribution substation. The outgoing line from the low-voltage end of the transformer is 0. 4kV to the distribution cabinet (primary distribution cabinet), then the outgoing line is led to the distribution box (secondary distribution box) in each building, and finally the outgoing line is led to the distribution cabinet. 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.
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