Usually, electrical equipment such as the main circuit breaker, main leakage protector, voltmeter, and ammeter are installed in the main distribution box, which is used for centralized management and monitoring of the power at the entire construction site. Electrical equipment is installed under the switch box, forming a three-level distribution. "Two level protection" mainly refers to the use of leakage protection measures. 4kV), power distribution is achieved through three levels of distribution boxes: the main distribution board, secondary distribution boards, and tertiary distribution boards. Main Distribution Board Serves as the primary. From the transformer's low-voltage side (0.