It assembles switchgear, measuring instruments, maintenance appliances, and auxiliary facilities according to electrical wiring standards, into enclosed or semi-enclosed metal cabinets or panels, thereby forming a distribution box. During operation, it can connect or disconnect the circuit using an assistant or an automatic switch. In case of a fault or failure to operate, the circuit is cut off or an alarm is triggered by the electrical appliances. It also utilizes instruments to display various parameters during operation, achieving the effect of adjusting parameters and maintaining normal status.