Generally, first level distribution does not allow direct use of electrical equipment, and second level distribution will be by power equipment because it is three-phase electricity, while third level distribution is mains electricity (220V). As for the equipment inside, there are certain. The terms primary, secondary, and tertiary distribution boxes are relative. Let's make an example for clarity: A newly constructed residential area introduces a 10kV power line to a substation. From the transformer's low-voltage side (0. 4kV), power is distributed to a main distribution panel. That is, a distribution electric box is arranged under the general distribution box, and a switch box is arranged under the switch box, and electrical equipment is arranged under the switch box to form a three-level distribution. These boxes feature bottom entry and exit cables, front-opening doors, and main busbars connected with copper strips for optimal contact. Note: The three-level power distribution is mainly to ensure that each power-consuming device has electricity available; each power-consuming device can be used.
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