Three level distribution box: a distribution box is set under the main distribution box, a switch box is set under the distribution box, and electrical equipment is set under the switch box to form a three-level distribution box. Let's make a hypothesis: a newly built residential area introduces a 10kV incoming line and builds a distribution room. The outgoing line from the low-voltage end of the transformer is 0. 4kV to. Forms a complete three-level protection system to achieve one machine, one switch, and one protection. Features bottom entry and exit cables, front-opening doors, copper busbars for main connections, metering systems, and rainproof tops for outdoor work.